POINT Guard I/O Safety Modules User Manual

POINT Guard I/O Safety

Modules

Catalog Numbers 1734-IB8S, 1734-IB8SK, 1734-IE4S,

1734-IE4SK, 1734-OB8S, 1734-OB8SK, 1734-OBV2S, 1734-OBV2SK

 

POINT Guard I/O Safety Modules User Manual

Important User Information

Read this document and the documents listed in the additional resources section about installation, configuration, and operation of this equipment before you install, configure, operate, or maintain this product. Users are required to familiarize themselves with installation and wiring instructions in addition to requirements of all applicable codes, laws, and standards.

Activities including installation, adjustments, putting into service, use, assembly, disassembly, and maintenance are required to be carried out by suitably trained personnel in accordance with applicable code of practice.

If this equipment is used in a manner not specified by the manufacturer, the protection provided by the equipment may be impaired.

In no event will Rockwell Automation, Inc. be responsible or liable for indirect or consequential damages resulting from the use or application of this equipment.

The examples and diagrams in this manual are included solely for illustrative purposes. Because of the many variables and requirements associated with any particular installation, Rockwell Automation, Inc. cannot assume responsibility or liability for actual use based on the examples and diagrams.

No patent liability is assumed by Rockwell Automation, Inc. with respect to use of information, circuits, equipment, or software described in this manual.

Reproduction of the contents of this manual, in whole or in part, without written permission of Rockwell Automation, Inc., is prohibited. Throughout this manual, when necessary, we use notes to make you aware of safety considerations.

WARNING: Identifies information about practices or circumstances that can cause an explosion in a hazardous environment, which may lead to personal injury or death, property damage, or economic loss.

ATTENTION: Identifies information about practices or circumstances that can lead to personal injury or death, property damage, or economic loss. Attentions help you identify a hazard, avoid a hazard, and recognize the consequence.

IMPORTANT Identifies information that is critical for successful application and understanding of the product.

These labels may also be on or inside the equipment to provide specific precautions.

SHOCK HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that dangerous voltage may be present.

BURN HAZARD: Labels may be on or inside the equipment, for example, a drive or motor, to alert people that surfaces may reach dangerous temperatures.

ARC FLASH HAZARD: Labels may be on or inside the equipment, for example, a motor control center, to alert people to

potential Arc Flash. Arc Flash will cause severe injury or death. Wear proper Personal Protective Equipment (PPE). Follow ALL Regulatory requirements for safe work practices and for Personal Protective Equipment (PPE).

The following icon may appear in the text of this document.

Identifies information that is useful and can help to make a process easier to do or easier to understand.

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Table of Contents

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Table of Contents

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Table of Contents

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Table of Contents

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Preface

Thoroughly read and understand this manual before you install and operate a

system that uses POINT Guard I/O™ modules.

Always observe the following guidelines when using a module. In this manual, we use safety administrator to mean a person who is qualified, authorized, and

responsible to secure safety in the design, installation, operation, maintenance, and disposal of the ‘machine’.

Keep this manual in a safe place where personnel can refer to it when necessary.

Use the module properly according to the installation environment, performance ratings, and functions of the machine.

See Understand Suitability for Use on page 9 and Safety Precautions on page 11.

Product specifications and accessories can change at any time. Consult with your Rockwell Automation representative to confirm specifications of the purchased product. Dimensions and weights are nominal and are not for manufacturing

purposes, even when tolerances are shown.

Consult your Rockwell Automation representative if you have any questions or comments. Also refer to the related documentation, which is listed on page 8, as necessary.

Summary of Changes This publication contains the following new or updated information. This list

Change

Pages

Removed all installation information from this manual, expect for wiring information and examples. See the POINT Guard I/O Safety Modules Installation Instructions, publication 1734-IN016, for

installation information.

Removed specifications from this manual. See the Point I/O Selection Guide, publication 1734-SG001, for a complete list of specifications.

Updated the pulse testing information.

159, 162, 163

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Preface

Terminology

Table 1 – Common Terms

Term

Means

Connection

Logical communication channel for communication between nodes. Connections are maintained and controlled between leaders and followers.

EDS

Electronic data sheet a template that is used in RSNetWorx™ software to display the configuration parameters, I/O data profile, and connection-type support for a given I/O module. RSNetWorx™ software uses these simple text files to identify products and commission them on a network.

PFD

Probability of a dangerous failure on demand, the average probability of a system to fail to perform its design function on demand.

PFH

Average frequency of a dangerous failure per hour, the probability of a system to have a dangerous failure occur per hour.

Proof test

Periodic test that detects failures in a safety-related system so that, if necessary, the system can be restored to an as-new condition or as close as practical to this condition.

SNN

Safety network number, which uniquely identifies a network across all networks in the safety system. You must assign a unique number for each safety network or safety subnet within a system.

Standard

Devices or portions of devices that do not participate in the safety function.

Additional Resources These documents contain additional information concerning related products

from Rockwell Automation.

Resource

Description

POINT Guard I/O Safety Modules Installation Instructions, publication 1734-IN016

Provides installation information for the safety I/O modules.

POINT I/O Selection Guide, publication 1734-SG001

Provides selection information for all POINT I/O™ modules.

GuardLogix 5570 Controllers User Manual, publication1756-UM022

Provides information on how to install, configure, program, and use GuardLogix® 5570 controllers in Studio 5000 Logix Designer® projects.

GuardLogix 5570 Controller Systems Safety Reference Manual, publication 1756-RM099

Provides information on safety application requirements for GuardLogix 5570 controllers in Studio 5000 Logix Designer projects.

GuardLogix Controller Systems Safety Reference Manual, publication 1756-RM093

Provides information on safety system requirements and describes the GuardLogix controller system.

GuardLogix Controllers User Manual, publication 1756-UM020

Provides information on how to install, configure, program, and use GuardLogix controllers in RSLogix 5000® projects.

GuardLogix Safety Application Instructions Safety Reference Manual,

publication 1756-RM095

Provides reference information that describes the GuardLogix Safety Application Instruction Set.

SmartGuard 600 Controllers Safety Reference Manual, publication 1752-RM001

Describes SmartGuard™ 600-specific safety requirements and controller features.

Field Potential Distributor Installation Instructions, publication 1734-IN059

Provides installation information for 1734-FPD distributors.

POINT I/O 24V DC Expansion Power Supply Installation Instructions,

publication 1734-IN058

Provides installation information for 1734-EP24DC power supplies.

POINT I/O 120/240VAC Expansion Power Supply Installation Instructions,

publication 1734-IN017

Provides installation information for 1734-EPAC power supplies.

POINT I/O Terminal Base Assembly Installation Instructions, publication 1734-IN511

Provides installation information for 1734-TB and 1734-TBS assemblies.

POINT I/O One-piece Terminal Base Installation Instructions, publication 1734-IN028

Provides installation information for 1734-TOP, 1734-TOPS, 1734-TOP3, and 1734-TOP3S terminal bases.

ODVA Media Planning and Installation Guide, www.odva.org

Describes the required media components and how to plan for and install these required components.

Industrial Automation Wiring and Grounding Guidelines, publication 1770-4.1

Provides general guidelines for installing a Rockwell Automation industrial system.

Product Certifications website, rok.auto/pec

Provides declarations of conformity, certificates, and other certification details.

You can view or download publications at rok.auto/literature.

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Chapter 1

POINT Guard I/O Overview

Topic

Page

Understand Suitability for Use

9

Safety Precautions

11

POINT Guard I/O Modules in CIP Safety Systems

13

Safety Application Requirements

17

Use the POINT Guard I/O™ safety modules in the POINT I/O™ platform to distribute safety I/O on a safety-control network that meets the requirements up to and including SIL CL3, and PLe, Cat. 4 as defined in IEC 61508, IEC 61511,

IEC 62061,and ISO 13849-1. Guard I/O™ modules can be used with

GuardLogix® controllers, Compact GuardLogix controllers, and SmartGuard™ controllers.

Configure the modules for use on DeviceNet® networks with RSNetWorx™ for DeviceNet software. For Ethernet networks, use the Logix Designer application.

 

Understand Suitability for Use

Rockwell Automation is not responsible for conformity with any standards,

codes, or regulations that apply to the combination of the products in your

application or use of the product. For more information see the POINT Guard I/O Safety Modules Installation Instructions, publication 1734-IN016, and the Point I/O Selection Guide, publication 1734-SG001.

Take all necessary steps to determine the suitability of the product for the systems, machine, and equipment with which it is used.

Know and observe all prohibitions of use applicable to these products. Use this equipment within its specified ratings.

Before you use these products for an application that involves serious risk to life or property, verify that the whole system is designed to address the risks. Be sure that Rockwell Automation products are properly rated and installed for the

intended use within the overall equipment or system.

Download firmware and product release notes from Rockwell Automation’s

Product Compatibility and Download Center. Do not download firmware from non-Rockwell Automation sites.

 

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POINT Guard I/O Overview

Verify that the POINT Guard I/O firmware revision is correct before you

commission the safety system. Firmware information for safety I/Omodules is available at rok.auto/pec.

Field power must be applied to the 1734-IE4S module when you update the firmware.

Verify that asafety administrator conducts a risk assessment on the machine and determines module suitability before installation.

ATTENTION: Personnel responsible for the application of safety-related

programmable electronic systems (PES) shall be aware of the safety

requirements in the application of the system and shall be trained in the use of the system.

ATTENTION: Use only appropriate components or devices that comply with relevant safety standards that correspond to the required safety category and safety integrity level.

Conformity to requirements of the safety category and safety integrity level must be determined for the entire system.

We recommend that you consult a certification body regarding assessment of conformity to the required safety integrity level or safety category.

You must confirm that the entire system is in compliance with the applicable standards.

Table 1 – Requirements for Device Control

Device

Requirement

Allen-Bradley® Bulletin Safety Components

Emergency stop switches

Use approved devices with direct opening mechanisms that comply with IEC/EN 60947-5-1.

Bulletin 800F, 800T

Door interlocking switches, limitswitches

Use approved devices with direct opening mechanisms that comply with IEC/EN

60947-5-1 and capable of switching microloads of 24VDC, 3 mA.

Bulletin 440K, 440G, 440H for interlockswitch Bulletin 440P, 802T for limit switch

Safety sensors

Use approved devices that comply with the relevant product standards, regulations, and rules in the country where used.

Any Guardmaster® product

Relays with forcibly-guided contacts, contactors

Use approved devices with forcibly guided contacts that comply with EN 50205. For feedback purposes, use devices with contacts capable of switching micro loads of 24VDC, 3 mA.

Bulletin 700S, 100S

Other devices

Evaluate whether the devices used are appropriate to satisfy the requirements of safety category levels.

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POINT Guard I/O Overview

Safety Precautions Observe these precautions for proper use of POINT Guard I/Omodules.

ATTENTION: As serious injury can occur due to loss of required safety function,

follow these safety precautions.

Never use test outputs as safety outputs. Test outputs are not safety outputs.

Do not use Ethernet, DeviceNet, or ControlNet® standard I/O data or explicit message data as safety data.

Do not use status indicators on the I/O modules for safety operations.

Do not connect loads beyond the rated value to the safety outputs.

Apply properly specified voltages to the module. If you apply inappropriate voltages, the module may fail to perform the specified functions, which could lead to loss of safety functions or damage to the module.

To wire the POINT Guard I/O modules properly, use the wiring requirements and guidelines in Wire the Modules on page 48.

Before you connect a device to the network, set a unique network node address.

To confirm that device wiring, configuration, and operation is correct before you begin system operation, perform the applicable tests.

Do not disassemble, repair, or modify the module. This can result in the loss of safety functions.

Install or Replace Modules

ATTENTION:

Before you connect devices to the network or connect input or output power to the device, clear previous configuration data.

Configure the replacement device properly and confirm that it operates correctly.

When you install or replace a module, follow the instructions and safety

precautions in the POINT Guard I/O Safety Modules Installation Instructions, publication 1734-IN016.

After the module is installed, a safety administrator must confirm the installation and conduct trial operation and maintenance.

When you clean a module, do not use these chemicals.

Thinner

Benzene

Acetone

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POINT Guard I/O Overview

Limit Access to the System

When you limit access to a device to authorized users only, consider these options:

Password protect the source and execution of the control program

Remove the key from the controller

Deploy EtherNet/IP™ devices in accordance with recommended

architectures and concepts. See the Converged Plantwide Ethernet

(CPwE) Design and Implementation Guide, publication ENET-TD001

Implement physical barriers, such as locked cabinets To limit access to the system, consider these options:

Follow industry best practices to harden your personal computers and servers, like antivirus/anti-malware and application allow list solutions. These recommendations are published in Knowledgebase Document ID

PN767.

Develop and deploy backup and disaster recovery policies and procedures. Test backups on a regular schedule.

Minimize network exposure for all control system devices and systems, and verify that they are not accessible from the Internet.

Locate control system networks and devices behind firewalls and isolate them from the business network.

Subscribe to Rockwell Automation’s Security Advisory Index,

Knowledgebase Document ID PN1354, so you have access to information

about security matters that affect Rockwell Automation products.

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POINT Guard I/O Overview

POINT Guard I/OModules in CIP Safety Systems

POINT Guard I/O modules are used in the POINT I/Oplatform and

implement CIP Safety™ protocol extensions over EtherNet/IP and DeviceNet networks to communicate safety messages. POINT Guard I/Omodules connect to EtherNet/IP or DeviceNet networks via these network adapters.

Table 2 – Network Adapters

Network

System

Adapter(1)

EtherNet/IP

GuardLogix

1734-AENT (Firmware Revision 3 or later)

1734-AENTR

DeviceNet

SmartGuard or GuardLogix

1734-PDN

(1) Not compatible with 1734-ADN, 1734-ADNX, 1734-APB, or 1734-ACNR adapters.

Distributed I/O communication for safety I/O data is performed through safety connections that support CIP Safety over an EtherNet/IP or DeviceNet

network. Data is processed in the safety controller. A control monitors the status and fault diagnostics of POINT Guard I/Omodules.

In addition to I/O state data, the modules include status data to monitor I/O faults within each circuit.

A password can help protect the configuration information of the modules.

1734-IB8S Digital Input Module Features

Safety digital inputs

Safety devices, such as an Emergency Stop Push Button, gateswitches, and safety light curtains, can be connected.

Dual-channel mode evaluates consistency between two input signals (channels), which allows use of the module for safety Category 3 and 4 and in applications that are rated up to and including PLe/SIL CL3 when both channels’ Point Mode configurations are set to Safety Pulse

Test.

Single-channel mode evaluates one input signal (channel),which allows use of the module for safety Category 2 and in applications that are

rated up to and including PLd/SIL CL2 when the channel’s Point Mode configuration is set to Safety Pulse Test.

You can configure a discrepancy time to control how long two channels are allowed to be discrepant before a fault is declared.

It is possible to perform an external wiring short circuit check when

inputs are wired in combination with test outputs. The module must be wired in combination with test outputs when this function is used.

Independently adjustable on and off delays are available per channel.

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POINT Guard I/O Overview

Test outputs (digital input modules only)

Separate test outputs are provided for short circuit detection of a safety input (or inputs).

Power (24V) can be supplied to devices, such as safety sensors.

Test outputs can be configured as standard outputs.

Specific test outputs can be used for broken-wire detection of a muting lamp.

1734-OB8S Safety Digital Output Module Features

Solid-state outputs

Dual-channel mode provides redundant control with two output signals (channels), which lets you use the module for safety Category 3 and 4, and applications that are rated up to and including PLe/SIL CL3 when both channels’ Point Mode configurations are set to Safety Pulse Test.

Single-channel mode provides control with one output signal (channel), which allows use of the module for safety Category 2, and applications that are rated up to and including PLd/SIL CL2 when the channel’s Point

Mode configuration is set to Safety Pulse Test.

IMPORTANT 1734-OB8S Single-channel mode is only certified for functional safety

applications with process safety times greater than or equal to 600 ms; or, applications with demand rates less than or equal to 1 demand per minute.

Safety outputs can be pulse-tested to detect field wiring short-circuits to 24VDC.

1734-OBV2S POINT Guard I/OModule Features

Four bipolar outputs (two pairs)

Dual-channel mode provides redundant control with two output signals (channels), which allows use of the module for safety Category 3 and 4, and applications that are rated up to and including PLe/SIL CL3 when both channels’ Point Mode configurations are set to Safety Pulse Test.

Safety outputs can be pulse-tested to detect field wiring short-circuits to 24V DC (for the sourcing output of the bipolar pair) and ground (for the sinking output of the bipolar pair).

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POINT Guard I/O Overview

1734-IE4S Safety Analog Input Module Features

Connection of up to four voltage or current sensors.

Sensor power outputs are individually current-limited and monitored.

Measurement of process variables, such as temperature, pressure, or flow rate.

Seven configurable input ranges.

±10V, ±5V, 0…5V, 0…10V, 4…20 mA, 0…20 mA, Tachometer

Tachometer mode converts 24V DC switching signals into pulses per second.

Single-channel or dual-channel for SIL 3-rated safety devices and applications.

Dual-channel mode evaluates the consistency between two input signals (channels), which allows use of the module in applications that are rated

up to and including SIL CL3/PLe/Cat. 4.

You can configure a discrepancy time to control how long two channels are allowed to be discrepant before a fault is declared.

Programming Requirements

Use the minimum Software Versions listed here.

Cat. No.

Studio 5000® Environment Version

RSLogix 5000® Software Version

(EtherNet/IP Network)

RSNetWorx for DeviceNet

Software Version

(DeviceNet Network)

1734-IB8S, 1734-OB8S

21 or later

17(1)or later

9 or later

1734-OBV2S

21 or later

18 or later

21 or later

1734-IE4S

21 or later

18(2)or later

10 or later

(1) If you use digital POINT Guard I/O modules with the analog POINT Guard I/O module, you must update the Add-on Profiles to version 2.02.004 or later for the modules to be compatible with version 18 or later of RSLogix 5000 software and the Studio 5000

Environment. To find Add-on Profiles, goto theProduct Compatibility and Download Center.

(2) Dual-channel Analog (DCA) safety application instruction is available in RSLogix 5000® software, version 20 or later and Studio 5000® environment, version 21 and later.

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POINT Guard I/O Overview

CIP Safety Architectures

Use POINT Guard I/O modules in EtherNet/IP or DeviceNet safety

architectures. Safety controllers control the safety outputs. Safety or standard PLC controllers can control the standard outputs.

Figure 1 – POINT Guard I/O Modules in EtherNet/IP Safety Architecture

GuardLogix Controller

Stratix® Switch

CompactBlock™ Guard I/O™

Safety Communication Standard Communication

Figure 2 – POINT Guard I/O Modules in DeviceNet Safety Architectures

GuardLogix Controller

SmartGuard Controller

CompactBlock™ Guard I/

Safety Communication POINT Guard I/O and POINT I/O

Standard Communication

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POINT Guard I/O Overview

 

Safety Application Requirements

POINT Guard I/O modules are certified for use in safety applications up to and including PLe/Cat. 4 and SIL CL3 in which the de-energized state is the safe

state. Safety application requirements include evaluation of probability of failure rates (PFD and PFH), system reaction time settings, and functional verification tests that fulfill SIL 3 criteria.

Creating, recording, and verifying the safety signature is also a required part of the safety application development process. The safety controller creates the

safety signatures. The safety signature consists of an identification number, date, and time that uniquely identifies the safety portion of a project. This number includes all safety logic, data, and safety I/Oconfiguration.

For safety system requirements, including information on the safety network

number (SNN), verifying the safety signature, functional verification test

intervals, system reaction time, and PFD/PFH calculations, refer to the following publications.

 

For safety requirements in:

See:

GuardLogix controller systems

GuardLogix 5570 Controller Systems Safety Reference

Manual, publication 1756-RM099

SmartGuard 600 controller systems

SmartGuard 600 Controllers Safety Reference Manual,

publication 1752-RM001

You must read, understand, and fulfill the requirements that are detailed in these publications before operating a safety system that uses POINT Guard I/O

modules.

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POINT Guard I/O Overview

Notes:

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Chapter 2

Safety Inputs, Safety Outputs, and Safety Data

Topic

Page

Safe States

19

Safety Inputs – 1734-IB8S

20

Safety Analog Inputs – 1734-IE4S

27

Safety Outputs – 1734-OB8S, 1734-OBV2S

35

Muting Lamp Operation – 1734-IB8S

38

I/O Status Data

39

Safe States POINT Guard Digital I/O Modules

ATTENTION:

The safe state of the outputs is defined as the off state.

The safe state of the module and its data is defined as the off state.

Use the POINT Guard I/O™ module only in applications where the off state is the safe state.

The digital POINT Guard I/O™ modules have these safe states:

Safety outputs: OFF

Safety input data to network: OFF (single channel and dual-channel equivalent)

Safety input data to network: OFF/ON for input channels n/n+1 (dual-channel complementary)

Figure 3 – Safety Status

Networks Inputs to Network OFF

Output OFF Input

44076

The module is designed for use in applications where the safe state is the off state.

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Safety Inputs, Safety Outputs and Safety Data

POINT Guard I/O Analog Input Module

The analog input POINT Guard I/O module has these safe states:

Safety input data to network in single-channel configuration: 0 (OFF)

Safety input data to network in dual-channel equivalent configuration:

If a diagnostic fault occurs, the signal for the faulted channel is set to 0 (OFF).

If a dual-channel discrepancy fault occurs, the dual-channel inputs continue to report actual input signals.

Safety Inputs- 1734-IB8S Safety inputs are used to monitor safety input devices.

Use a Test Output with a Safety Input

A test output can be used in combination with a safety input for short circuit, cross-channel, and open-circuit fault detection. Configure the test output as a pulse test source and associate it to a specific safety input.

The test output can also be configured as a power supply to source 24V DC to an external device, for example, a light curtain.

Figure 4 – Example Use of a POINT Guard I/OInput Module

I0

I2

COM

TO

0

2

4

6

I1

I3

COM

T1M

1

3

5

7

I4

I6

COM

T2

0

2

4

6

I5

I7

COM

T3M

1

3

5

7

 

Where:

T0 = Test Output 0

T2 = Test Output 2

I0…I7 = Safety Inputs

T1M = Test Output 1 with Muting T3M = Test Output 3 with Muting

 

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Safety Inputs, Safety Outputs and Safety Data

Figure 5 – Test Pulse in a Cycle

: On

OUT

X Y Off

For the 1734-IB8S module, the pulse width (X) is typically 525 μs; the pulse period (Y) is typically 144 ms.

When the external input contact is closed, a test pulse is output from the test output terminal to diagnose the field wiring and input circuitry. When you use this function, short-circuits between inputs and 24V power, and between input signal lines and open circuits can be detected.

Figure 6 – Short-circuit between Input Signal Lines

Short-circuit between Input Signal Lines and Power

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Safety Inputs, Safety Outputs and Safety Data

Single-channel Mode

If an error is detected, safety input data and safety input status turnoff.

Figure 7 – Normal Operation and Fault Detection (Not to Scale)

 

24V

Test Output 0

0V

ON

Safety

I/O

Network Data Sent to the

Controller

External Device

Input Terminal 0

Safety Input 0 Data

Safety Input 0 Status

 

 

Fault Detection

Safety

I/O

Network Data Sent to the

Controller

Test Output 0

External Device

Input Terminal 0

Safety Input 0 Data

Safety Input 0 Status

24V

0V ON

OFF

ON

OFF ON

OFF

ON

OFF

Fault Detected

 

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Safety Inputs, Safety Outputs and Safety Data

Dual-channel Mode and Discrepancy Time

To support dual-channel safety devices, the consistency between signals on two channels can be evaluated. Either equivalent or complementary can be selected.

If the length of a discrepancy between the channels exceeds the configured

discrepancy time (10…65,530 ms in increments of 10 ms), the safety input data and the individual-safety input status turnoff for both channels. In Dual-channel Complimentary mode, the safety input data goes to off/on for input channels

n/n+1 respectively as described in Table 3.

IMPORTANT The dual-channel function is used with two consecutive inputs that are paired

together, and start at an even input number, such as inputs 0 and 1, 2 and 3.

IMPORTANT If you use the safety application instructions with a GuardLogix® controller, set

the inputs of the module inputs to Single (default). Do not use the

dual-channel mode of the module, as this functionality is provided by the safety application instructions.

This table shows the relation between input terminal states and controller input data and status.

Table 3 – Terminal Input Status and Controller I/O Data

Dual-channel Mode

Input Terminal

Controller Input Data and Status

Dual-channel Resultant

Data

Dual-channel Resultant

IN0

IN1

Safety

Input 0 Data

Safety

Input 1 Data

Safety

Input 0 Status

Safety

Input 1 Status

Dual-channels, Equivalent

OFF

OFF

OFF

OFF

ON

ON

OFF

Normal

OFF

ON

OFF

OFF

OFF

OFF

OFF

Fault

ON

OFF

OFF

OFF

OFF

OFF

OFF

Fault

ON

ON

ON

ON

ON

ON

ON

Normal

Dual-channels, Complementary

OFF

OFF

OFF

ON

OFF

OFF

OFF

Fault

OFF

ON

OFF

ON

ON

ON

OFF

Normal

ON

OFF

ON

OFF

ON

ON

ON

Normal

ON

ON

OFF

ON

OFF

OFF

OFF

Fault

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Safety Inputs, Safety Outputs and Safety Data

Dual-channel, Equivalent

In Equivalent mode, both inputs of a pair must be in the same (equivalent) state. When a transition occurs in one channel of the pair before the transition of the second channel of the pair, a discrepancy occurs. If the second channel transitions to the appropriate state before the discrepancy time elapses, the inputs are

considered equivalent. If the second transition does not occur before the

discrepancy time elapses, the channels will fault. In the fault state, the input and status for both channels are set low (OFF). When configured as an equivalent dual pair, the data bits for both channels are sent to the controller as equivalent, both high or both low.

Figure 8 – Equivalent, Normal Operation and Fault Detection (Not to Scale)

 

Normal Operation IN0

IN1

Safety

I/O

Network Data Sent to the

Controller

Safety Input 0 Data

Safety Input 1 Data

Safety Input 0, 1

Status

ON

OFF

ON

OFF ON

OFF

ON

OFF

ON

OFF

Discrepancy Time

 

 

Fault Detection

Safety

I/O

Network Data Sent to the

Controller

IN0

IN1

Safety Input 0 Data

Safety Input 1 Data

Safety Input 0, 1 Status

ON

OFF ON

OFF

ON

OFF ON

OFF

ON

OFF

Discrepancy Time

Fault Detected

 

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Safety Inputs, Safety Outputs and Safety Data

Dual-channels, Complementary

In Complementary mode, the inputs of a pair must be in the opposite

(complementary) state. When a transition occurs in one channel of the pair

before the transition of the second channel of the pair, a discrepancy occurs. If the second channel transitions to the appropriate state before the discrepancy time elapses, the inputs are considered complementary.

If the second transition does not occur before the discrepancy time elapses, the channels will fault. The fault state of complementary inputs is the

even-numbered input that is turned off and the odd-numbered input turned ON. Note that if faulted, both channel status bits are set low. When configured as a complementary dual-channel pair, the data bits for both channels are sent to the controller in complementary, or opposite states.

Figure 9 – Complementary, Normal Operation and Fault Detection (Not to Scale)

 

IN0

IN1

Safety Input 0

Data

Safety Input 1 Data

Safety Input 0, 1

ON

OFF

ON

OFF ON

OFF

ON

OFF

ON

OFF

Discrepancy Time

 

 

Fault Detection IN0

IN1

Safety

I/O

Network Data Sent to the

Controller

Safety Input 0 Data

Safety Input 1 Data

Safety Input 0, 1 Status

ON

OFF ON

OFF

ON

OFF ON

OFF

ON

OFF

Discrepancy Time

Fault Detected

 

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Safety Inputs, Safety Outputs and Safety Data

Safety Input Fault Recovery

If an error is detected, the safety input data remains in the OFF state. Follow this procedure to activate the safety input data again.

1. Remove the cause of the error.

2. Place the safety input (or safety inputs) into the safe state.

3. Allow the input-error latch time to elapse.

After these steps are completed, the I/O indicator (red) turns off. The input data is now active.

Input Delays

On-delay – An input signal is treated as Logic 0 in the on-delay time (0…126 ms, in increments of 6 ms) after the rising edge of the input contact. The input turns on only if the input contact remains on after the on-delay time has elapsed. This setting helps prevent rapid changes of the input data due to contact bounce.

Figure 10 – On-delay

Safety Input Network Data

Off-delay – An input signal is treated as Logic 1 in the off-delay time (0…126 ms, in increments of 6 ms) after the falling edge of the input contact. The input turns off only if the input contact remains off after the off delay time has elapsed. This setting helps prevent rapid changes of the input data due to contact bounce.

Figure 11 – Off-delay

44095

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Safety Inputs, Safety Outputs and Safety Data

 

Safety Analog Inputs- 1734-IE4S

Safety analog-input channels can be configured for current, voltage, or

tachometer inputs, and for input type: single-channel or dual-channel equivalent.

IMPORTANT

If you use the module with a GuardLogix controller, set the inputs of the

module to Single (default). Do not use the dual-channel equivalent mode of the modules with the GuardLogix dual channel safety application instructions, as dual-channel functionality is provided by the GuardLogix instructions.

Input Range

You can configure the module for these voltage or current input ranges, or for tachometer inputs.

±10V ±5V

0…5V

0…10V

4…20 mA

0…20 mA

Tachometer (1…1000 Hz)

IMPORTANT When ±10Vand ±5V ranges are selected, you must make sure that a

broken-wire condition is not a safety hazard. A broken wire causes the analog value to transition to 0, which is within the valid input range. Therefore, status bits do not indicate the broken-wire condition.

Scale the Input Signals

The module converts input signals to the engineering units specified when you configure the module. You set the High Engineering value and the Low

Engineering value to which the module scales the input signal before the data is sent to the application program of the controller.

EXAMPLE The module is configured as follows:

Input Range = 0…10V

Low Engineering value = 0

High Engineering value = 10,000

If the incoming signal is 1V, the data is 1000. If the incoming signal is 5.5V, the data is 5500.

 

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Safety Inputs, Safety Outputs and Safety Data

Digital Input Filter

A single-pole, anti-alias filter of 10 Hz is followed by a four-pole digital filter. Choose from these available corner frequencies.

1 Hz 5 Hz 10 Hz

50 Hz

The default input filter setting is 1 Hz.

 

Figure 12 Filter Operation

Anti-alias Filter

Configurable Digital Filter Settings N = 1 Hz, 5 Hz, 10 Hz, or 50 Hz

 

1

The filter setting affects the step response of the module. For more information, see the Point I/O Selection Guide, publication 1734-SG001.

For the analog input modes, the input filter settings set the low-pass filter to filter out noise that can be present on the signal. In Tachometer mode, the input filter removes noise that can be present on the calculated frequency, this effectively

changeshow rapidly the tachometer frequency changes to provide a value with less jitter.

Sensor Power Supply

You can configure the module to supply power to the connected sensors, or you can supply power to the sensors from an external power supply. To comply with UL restrictions, you must power the field power and connected devices with one, Class 2-complaint power supply.

Werecommend that you configure the module to supply power to the sensors. This configuration lets the module detect if a sensor loses power, if the sensor draws too much power, or if there is a short in the power wiring to the sensor.

At powerup or after areconfiguration, each sensor power supply is turned on for

500 ms to test them.

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Safety Inputs, Safety Outputs and Safety Data

When a channel is configured for module sensor power, a sensor power

diagnostic is executed on that channel at powerup. The diagnostic is used to make sure that the sensors do not draw over-or undercurrent and that

channel-to-channel shorts are not present.

When a sensor power overcurrent condition occurs, it can take as much as 15 seconds longer than the configured latch time for channel status to recover after the overcurrent condition is cleared.

IMPORTANT If you use an external power supply, you must monitor the system for the

following:

The supply voltage must be within the operating range of the sensor.

The current draw of the sensors must not be over or undercurrentcurrent, which could indicate a problem with the components of the sensor.

Channeltochannel shorts must be detected, if they occur.

Channel Offset

You can configure an offset if differences of the nominal input signal in the sensor exceed the desired discrepancy deadband. Use the Channel Offset if you use two sensors of different types to measure the same variable. Sensors from two

different vendors potentially give slightly different data values for a given

temperature or pressure. Use the Channel Offset to bring the data values back together. You can also use the Channel Offset with two identical sensors that are physically offset from each other.

The channel offset is applied before the channel discrepancy is evaluated.

The Channel Offset is applied only during the evaluation of discrepancy between two

channels that are configured for Dual Channel and is not applied to any of the Process

Alarms. Therefore, if you use two sensors to measure the same process variable, and these sensors read different values, you may need to set the Process Alarms to different values based on the sensor readings.

Process Alarms

Process alarms alert you when an analog input value has exceeded the configured high or low limits for each channel. Process alarms are set at four configurable trigger points.

High High alarm

High alarm

Low alarm

Low Low alarm

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Safety Inputs, Safety Outputs and Safety Data

You can configure a tolerance range, called a deadband, to work with process alarms. This deadband lets the process alarm status bit remain set, despite the disappearance of the alarm condition, as long as the data remains within the deadband of the process alarm.

IMPORTANT

If you use the safety application instructions with a GuardLogix controller, do not use the process alarm of the module. Instead, check the analog range in your application logic.

Figure 13 – Alarms

High High alarm turns OFF. High alarm remains ON.

High High Alarm

High alarm turns

ON.

High Alarm

Normal input range

Low Alarm

Low Low Alarm

Low Low alarm turns ON. Low alarm remains ON. Low Low alarm turns OFF. Low alarm remains ON.

Use a Single-channel Sensor

You must address these requirements to meet SIL 3 with asingle-channel sensor.

The module’s ±10Vand ±5V analog input modes must not be used for SIL 3 with a single-channel sensor because 0V falls within the valid input range. Therefore, a stuck at ground fault cannot be detected.

In a single-channel sensor system, you must use other methods to make sure a channel-to-channel short cannot occur because these faults cannot be detected.

If you use a 3-wire sensor, you must verify its behavior to make sure that if it loses its ground connection, the signal is 0 (safe state) at the module

input when the fault occurs.

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Safety Inputs, Safety Outputs and Safety Data

Dual-channel Equivalent Mode

IMPORTANT If you use the module with a GuardLogix controller, set the inputs of the

module to Single (default). Do not use the dual-channel mode of the module as this functionality is provided by the GuardLogix safety application

instructions.

The 1734-IE4S module supports Dual-channel Equivalent mode. In

Dual-channel Equivalent mode, the values of both inputs of a pair must be within a configured tolerance range (discrepancy deadband). If the difference between

the channel values exceeds the deadband for longer than the configured

discrepancy time, a discrepancy fault is declared. When a dual-channel

discrepancy fault occurs, the input status values for both channels are set low (off) and the actual input values are reported. The fault is cleared when the difference between the values of the channel fallback within the discrepancy deadband tolerance range for the discrepancy time.

Figure 14 illustrates module operation in dual-channel equivalent mode. At A, the difference between the channel values exceeds the discrepancy deadband

tolerance range and the discrepancy timer starts. When the timer expires at B, a dual-channel discrepancy fault occurs and the status bits of the input are set low. At C, the values fallback within the discrepancy deadband and the discrepancy timer starts again. When the timer expires at D, and the values are still within the discrepancy deadband, the fault is cleared. At E, the difference between the

channels exceeds the discrepancy deadband and the discrepancy timer starts. A discrepancy fault occurs again at F, when the timer expires and the difference between the channel values remains greater than the discrepancy deadband.

Figure 14 – Timing Diagram

 

High High Alarm High Alarm

Channel A

Channel B

Low Low Alarm Low Alarm

Fault Present

Input Status

1

0

1

0

Deadband

Difference between Channel A and Channel B Discrepancy Time = 250 ms

50

m

 

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Safety Inputs, Safety Outputs and Safety Data

Tachometer Mode

In Tachometer mode, the module measures digital pulses from 0V…24VDC, and converts them into a frequency or pulses per second. Therefore, you can use 24V DC proximity sensors or 5V DC encoders, for example. The Tachometer function does not sense direction, so the use of a differential encoder does not yield direction data. Tachometer mode could be used, for example, to measure the rotational speed of an axis that is connected to a gear.

Tachometer mode can operate as SIL 2 single-channel. Use two sensors, the dual-low detection parameter, and user program logic to achieve SIL 3. Safety reaction time is dependent on the signal frequency.

IMPORTANT When you use two sensors in a dual-channel configuration, position the

sensors to make sure that the low pulses occur at different times. If you have configured the module for duallow detection and both sensors are low

simultaneously, a fault is declared.

Figure 15 – Sensor Pulses in Dual-channel Configuration

 

Sensor 1

Sensor 2

Sensor 1

Sensor 2

Low pulses are offset.

Low pulses occur simultaneously and causes a fault.

 

Signal Measurement

The edge-to-edge time of the pulse determines the frequency of the signal in pulses per second. The frequency range is 1 Hz…1 kHz.

In Tachometer mode, you define how the signal is measured, either on the falling (non-inverted) or rising (inverted) edge. For NPN-style sensors (sensor sinks), use the falling edge. For PNP-style sensors (sensor sources), use the rising edge. Depending on your application, you may need to install an appropriately sized pull-up resistor for falling-edge signal measurements, or a pull-down resistor for rising-edge signal measurements.

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Safety Inputs, Safety Outputs and Safety Data

Figure 16 Pulse Trains

 

Ideal Pulse Train

Falling and rising edges are well-defined.

Falling edges are not well-defined.

Rising edges are not well-defined.

Falling Edge Rising Edge

Pull-down resistor helps define falling edges.

Pull-up resistor helps define rising edges.

 

Off and On Signal Levels

You configure the Off and On levels, in 1V increments, for the signal. When you select these levels, assume a tolerance of at least ±0.5V. For example, if you set the On Level to 10V, you can expect the module to recognize a signal from

9.5V…10.5Vas On. While the accuracy of the module when it measures the analog signal is good, Tachometer mode emphasizes a wider voltage range and speed to be able to measure pulse widths accurately.

Also consider the variance of the voltage output from your sensor when you make the On and Off Level settings. If possible, werecommend that you select On

Levels that are 2V below and Off Levels that are 2V above the actual thresholds of the expected output voltage level of your device.

Determine Frequency in Pulses per Second

The edge-to-edge time of either the falling or rising edge of the pulse determines the frequency in pulses per second.

One pulse, by itself, does not generate a nonzero frequency. To report a frequency of 1 Hz, two falling or rising edge pulses must be detected within 1 second. The module reports 0 Hz until 1 Hz is detected. For example, if a falling or rising edge is not detected for 1.02 seconds after the previous edge, the module reports 0 Hz.

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Safety Inputs, Safety Outputs and Safety Data

Overfrequency Bit Operation

When the frequency exceeds 1 kHz, the module reports a data value of 1 kHz, sets the Overfrequency status bit to 0, and latches it. While the Overfrequency bit is set to 0, you must use an alternate method to monitor the frequency of the system because the value reported by the module is latched at 1 kHz. Once you

have verified that the frequency is lower than 1 kHz, you can reset the

Overfrequency condition by setting the Reset Tach bit, which lets the module begin to measure the frequency of field pulses again.

If you set the Reset Tach bit while the frequency is still above 1 kHz, the

Tachometer Overfrequency bit transitions to 1 (within range) momentarily.

However, as soon as the module begins to measure pulses, it detects another

overfrequency condition and immediately set the Tachometer Overfrequency bit to 0 again. The Reset Tach bit is edge-sensitive.

ATTENTION: Before you reset the Overfrequency condition, you must use another method to verify that the actual frequency is lower than 1 kHz.

See Output Assemblies on page 171 for more information on how to reset the Overfrequency bit.

Figure 17 – Overfrequency Operation

 

kHz

1 Hz

Frequency = 0

Actual values are reported.

Monitor frequency via an alternate method.

Overfrequency

condition can be

cleared.

Overfrequency bit is set to 0. Frequency = 1000 Hz

A B C

 

In Figure 17, the module reports a frequency of 0 Hz until the frequency of the system reaches 1 Hz at A, when the module begins to report the actual value. At B, the frequency exceeds 1 kHz, the Overfrequency bit is set to 0, and the module continues to report a data value of 1 kHz. Between B and C, you must monitor the frequency by an alternate method because the value that is reported by the module is not always accurate. After C, the Overfrequency condition can be

cleared, provided you have used an alternate method to verify that the actual frequency is below 1 kHz.

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Safety Inputs, Safety Outputs and Safety Data

Safety Outputs – Read this section for information about safety outputs.

1734-OB8S, 1734-OBV2S

Safety Output with Test Pulse

When the safety output is on, the safety output can be configured to pulse test the safety output channel. This function lets you continuously test the ability of the safety output to remove power from the output terminals of the module. If an error is detected, the safety output data and individual safety output status turn off.

 

Figure 18 – Test Pulse in a Cycle

OUT

i On Off

I

44096

 

For the 1734-OB8S and 1734-OBV2S modules, the pulse width (X) is typically 475 μs; the pulse period (Y) is typically 575 ms.

IMPORTANT

To help prevent a malfunction in the connected device because of the test pulse, pay careful attention to the input response time of the output device.

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Safety Inputs, Safety Outputs and Safety Data

Dual-channel Mode

When the data of both channels is in the on state, and neither channel has a fault, the outputs are turned on. The status is normal. If a fault is detected on one

channel, the safety output data and individual safety output status turnoff for both channels.

Figure 19 – Set the Dual-channel Mode (Not to Scale)

 

Normal Operation

Safety I/O

Network

Data Sent to the

Controller

ON

OFF

ON

OFF ON

OFF

 

 

Fault Detection

Safety

I/O

Network Data Sent to the

Controller

OUT0

OUT1

Safety Output 0, 1

Status

ON

OFF

ON

OFF

ON

OFF

Error

Detected

 

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Safety Inputs, Safety Outputs and Safety Data

Single-channel Mode, 1734-OB8S Only

When the data of the channel is in the on state, and does not have a fault, the

output is turned on. The status is normal. If a fault is detected on the channel, the safety output data and individual safety output status turnoff.

Figure 20 – Set the Single-channel Mode (Not to Scale)

 

Normal Operation

OUT0

ON

OFF

 

 

Safety

I/O

Network Data Sent to the

Controller

Safety Output 0

Status

ON

OFF

 

Fault Detection

OUT0

Safety Output 0

Status

ON

OFF

ON

OFF

Safety

I/O

Network Data Sent to the

Controller

Safety Output Fault Recovery

If a fault is detected, the safety outputs are switched off and remain in the off state. Follow this procedure to activate the safety output data again.

1. Remove the cause of the error.

2. Command the safety output (or safety outputs) into the safe state.

3. Allow the output-error latch time to elapse.

After these steps are completed, the I/O indicator (red) turns off. The output data can now be controlled.

IMPORTANT Stuck high faults require a module power reset to clear the error.

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Safety Inputs, Safety Outputs and Safety Data

 

Muting Lamp Operation- 1734-IB8S

With firmware revision 1.002 and later, the operation of the muting status bits for test outputsT1 and T3 has changed. Your PLC processor program controls test outputsT1 and T3 to illuminate a muting lamp. Muting lamp status is

monitored with a test that runs periodically during every test interval to detect a burned-out lamp. The test runs repeatedly when the test output is commanded on. Figure 21 explainshow muting lamp operation, status, and fault detection are monitored.

 

The lamp test interval is 3 seconds. Two consecutive failed lamp tests are required to

declare a burned-out lamp condition. The lamp test does not always run immediately after the test output is energized. It starts at the next 3-second interval. To allow time for two consecutive test intervals, program a minimum Test Output On Time of 6 seconds.

Figure 21 – Muting Lamp Timing Diagram

4

Table 4 shows the expected behavior of the muting status for test outputsT1 and T3. Keep these points in mind as well:

When power is applied to the 1734-IB8S module, and T1 orT3 remains commanded off, the muting status defaults to on.

38 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Safety Inputs, Safety Outputs and Safety Data

This bit operation is designed to help prevent erroneous muting

instruction faults from the GuardLogix controller. This bit status is not always the true indication of a burned-out lamp.

IMPORTANT

Before you check the state of the corresponding muting status, be sure that the test output is commanded on. Once the test output is commanded on, a

maximum time of 6 seconds is required for the module to detect a burned-out lamp.

If a muting lamp circuit is open when power is applied to the module, the condition is detected when the test output is commanded on.

When a lamp burns out and is replaced, the fault (muting status bit) returns to the normal condition, independent of the state of the test output.

Table 4 – Muting Status Bit Operation

Test Output Commanded State

Lamp Condition

Muting

Status

Bit

Description

ON

Bad (open circuit)

0

Repair the lamp.

ON

Good

1

Normal condition. The lamp is operating properly.

OFF

Bad (open circuit)

0

If the lamp remains OFF after you cycle the T1 orT3 output, repair the lamp.

OFF

Good

1

Normal condition.

I/O Status Data In addition to I/O data, the module also provides status data to monitor the I/O

circuits. The status includes diagnostic data that the controllers read with 1 = ON/Normal and 0 = OFF/Fault/Alarm.

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Safety Inputs, Safety Outputs and Safety Data

Digital I/OStatus Data

This status data is monitored:

Individual Point Input Status

Combined Input Status

Individual Point Output Status

Combined Output Status

Individual Test Output Status

Individual Output Monitor (actual ON/OFF state of the outputs)

Individual Point status indicates whether each safety input, safety output, or test output is normal (normal: ON, faulted: OFF). For fatal errors, communication connections can be broken, so the status data cannot be read. Status bits are OFF in the controller data table when the connection is lost.

Combined status is provided by an AND of the status of all safety inputs or all safety outputs. When all inputs or outputs are normal, the respective combined status is ON. When one or more of them has an error, the respective combined status is OFF. This status is known as the combined safety input status or

combined safety output status.

Analog I/OStatus Data

Individual input status indicates whether each analog input point is normal (ON) or faulted (OFF). In addition, this diagnostic data is monitored:

User 24V Supply Overrange or Underrange

Sensor Power Overcurrent or Undercurrent

Channel Signal Overrange or Underrange

Broken Wire Detected (4…20 mA current mode)

Single-channel Discrepancy Error (channel fault)

In SIL 2 or SIL 3 operation,a single-channel discrepancy error occurs

when both measurements (internal to the module) of the same input signal are not within tolerance. If a single-channel discrepancy occurs, this

indicates a problem with the module. Input status is set to zero and a zero input value is reported for that channel.

SIL 3 Dual-channel Discrepancy Error (channel fault)

Alarms

High High and Low Low Alarm Overrange or Underrange

High and Low Alarms Overrange or Underrange

Dual-channel Tachometer DualLow Inputs Detected

Tachometer Frequency Overrange or Underrange

The alarm status is reported in the Alarm Status attribute for each channel.

40 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Chapter 3

Place Power Supplies and Modules in a System

Topic

Page

Choose a Power Supply

41

Power Supply Examples

43

Place Series A Digital and Analog Modules

45

Place Series B Digital Modules

46

 

Choose a Power Supply

The POINTBus™ backplane includes a 5V communication bus and field power bus that get their power from a communication adapter or expansion power

supplies. All POINT I/O™ modules are powered from the POINTBus backplane by either the adapter or expansion power supply. POINT I/Oadapters have

built-in power supplies. Use the information and examples in this chapter to determine if you need an expansion power supply in your system.

ATTENTION: To comply with the CE Low Voltage Directive (LVD), this

equipment, and all connected I/O, must be powered from a safety extra low voltage (SELV) or protected extra low voltage (PELV) compliant source.

For ULcompliant applications, the 1734-IB8S, 1734-OB8S, and 1734-OBV2S

modules, and all connected I/O, must be powered from a SELV or PELVcompliant power source that is rated 150VA maximum.

For ULcompliant applications, the 1734-IE4S module, the modulesfield power and connected I/O devices must be powered from a Class 2-compliant, limited voltage/limited current power source.

 

These Rockwell Automation® 1606 power supplies are SELVand PELVcompliant, and they meet the isolation and output hold-off time requirements of the SmartGuard™ 600

controller:

1606-XLP30E

1606-XLP50E

1606-XLP50EZ

1606-XLP72E

1606-XLP95E

1606-XLDNET4

1606-XLSDNET4

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Chapter 3 Guidelines for Placing Power Supplies and Modules in a System

Follow the safety precautions that are listed in Chapter 1 and the wiring

guidelines that are described in Chapter 4 before you connect a power supply to the system.

To choose which types of power supplies meet the system requirements, you must consider the power consumption requirements for the 5Vand 24V bus when you design a POINTBus backplane.

Choose from these power supplies for the POINTBus backplane and field power:

The 1734-EP24DC expansion power supply provides an additional 10 A of 24V DC field power and provides an additional 1.3 A of 5Vcurrent to the I/O modules to the right of the power supply.

The 1734-FPD field power distributor provides an additional 10 A of24V DC field power, and passes through all POINT I/O backplane signals and the 5V bus supplied to the left. It does not provide additional POINTBus backplane power which lets you isolate field power segments.

The 1734-EPAC expansion power supply (for standard I/O modules)

provides an additional 10 A of 120/240VAC field power and provides an additional 1.3 A of 5V current to the I/O modules to the right of the

power supply.

IMPORTANT If you use the 1734-EPAC expansion power supply to the left of the POINT

Guard I/O™ modules, you must use a 1734-FPD field power distributor or 1734-EP24DC expansion power supply. These distributors are used to isolate POINT Guard I/O field power from the AC field supply.

5V POINTBus power is required to establish and maintain communication (connection) between the module and the controller.

See the POINT I/O Selection Guide, publication 1734-SG001, for more information on compatible power supplies.

42 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Guidelines for Placing Power Supplies and Modules in a System

Power Supply Examples Use these valid power-supply example configurations to help you understand the

combinations of power supplies that can fit your system:

Example 1: Isolate Field Power Segments on page 43

Example 2: POINT Guard I/O Used with AC I/O Modules on page 44

These examples are for illustrative purposes only, to help you understand various power supply concepts.

IMPORTANT You must define the requirements for field and bus power segments in

your application.

The POINT Guard I/O modules DO NOT require separate field bus power usage, that is, separate power supplies. This step is optional.

The POINT Guard I/O modules DO NOT require a separate POINTBus

power-supply, which separates a module from other POINT I/O modules, except when additional POINTBus power is required.

Do not apply AC voltage to POINT Guard I/Omodules.

Example 1: Isolate Field Power Segments

This power supply example uses a 1734-EP24DC expansion power supply and 1734-FPD field power distributor to illustrate a combination of standard

POINT I/O and POINT Guard I/O modules. The example illustrates how you can mix the modules and create separate groups for input and output modules, along with digital and analog modules.

Group 1

Group 2

Group 3

Group 4

Group 5

EtherNet/IP Adapter

1734-AENT 5V

24V

Standard I/O

Standard I/O

Standard I/O

Standard I/O

Standard I/O

Standard I/O

Standard I/O

Standard I/O

1734-EP24DC5V

1734-IB8S

1734-IB8S

1734-FPD

1734-OB8S

1734-OBV2S

1734-FPD

1734-IE4S

1734-IE4S

1734-EP24DC5V

Standard I/O

Standard I/O

Standard I/O

Standard I/O

1734-IB8S

24V

24V

24V

24V

5V Supply for All Safety

Modules and 24V Supply

for Safety Inputs

24VSupply for Safety Outputs

24VSupply for

Safety

Analog Inputs

5Vand 24VSupply for

Additional I/O

Modules (option)

Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 43

 

Guidelines for Placing Power Supplies and Modules in a System

Example 2: POINT Guard I/O Used with ACI/O Modules

This power supply example uses 1734-EP24DC and 1734-EPAC expansion power supplies to illustrate how you can mix POINT I/O and POINT Guard I/O modules,and create a separate power group for ACI/Omodules.

Group 1

Group 2

Group 3

1734-AENTEtherNet/IP Adapter 5V

24V

Standard I/O

Standard I/O

Standard I/O

Standard I/O

Standard I/O

1734-EP24DC5V

1734-IB8S

1734-IB8S

1734-OB8S

1734-OBV2S

1734-IE4S

1734-EPAC5V

Standard I/O

Standard I/O

Standard I/O

Standard I/O

24V

120V AC

5Vand 24VSupply for Safety Inputs and Outputs

44 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Guidelines for Placing Power Supplies and Modules in a System

 

Place Series A Digital and Analog Modules

Always install modules in accordance with their specified operating temperature ratings, and provide a minimum of 5.08 CM (2 in.) clearance above the modules.

For more information, see the Point I/O Selection Guide, publication 1734-SG001.

Limit ambient temperature operation to 40 °C (104 °F) if Series A POINT Guard I/O modules are used without 1734-CTM spacer modules.

Figure 22 – Series ADigital Modules in Operating Temperatures Less than 40 °C (104 °F)

Y 5.08 cm (2 in.)

1734-AENT

1734-IB8S/A

1734-OB8S/A

1734-IE4S/A

1734-IB8S/A

1734-IE4S/A

1734-IE4S/A

 

In any system where you have any Series A POINT Guard I/Omodules, use a 1734-CTM spacer between every POINT Guard I/Omodule with ambient operation between 40 °C (104 °F) and 55 °C (131 °F).

Insert a 1734-CTM module next to each standard I/O module (gray) if the thermal dissipation specification of that module is more than 1 W.

Figure 23 – Series A Digital and Analog Modules in Operating Temperatures from 40 °C (104 °F)…55 °C (131 °F)

5.08 cm (2 in.)

1734-AENT

1734-IB8S/A

1734-OB8S/A

1734-IE4S/A

1734-IB8S/A

1734-IE4S/A

1734-IE4S/A

1734-CTM

When you use Series A POINT Guard I/O modules in your system limit the power supply to 24V DC maximum, to limit the Series A POINT

Guard I/Othermal dissipation of the module.

For more information, see the Point I/O Selection Guide, publication 1734-SG001.

ATTENTION: Vertical orientation requires careful attention to design details and panel layout so that all modules in the stack must operate within their rated operating temperature range.

For Vertical installations, be sure that 1734-CTMspacer modules are installed next to any Series A POINT Guard IO modules operating above 40 °C (104 °F) ambient.

Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 45

 

Guidelines for Placing Power Supplies and Modules in a System

 

Place Series B Digital Modules

Always install modules in accordance with their specified operating temperature ratings, and provide a minimum of 5.08 CM (2 in.) clearance above the modules.

When used in a system that contains only Series B Guard I/O modules, series B

Guard I/O modules are used without 1734-CTM spacer modules in environments with ambient operation up to 55 °C (131 °F).

For Series B POINT Guard I/O module derating requirements for every module with ambient operation between 40 °C (104 °F) and 55 °C (131 °F),see the

specifications in the Point I/O Selection Guide, publication 1734-SG001.

Figure 24 – Series BDigital Modules in Operating Temperatures Less than 55 °C (131 °F)

5.08 cm (2 in.)

1734-AENT

1734-IB8S/B

1734-OB8S/B

1734-IB8S/B

1734-OB8S/B

1734-IB8S/B

1734-OB8S/B

ATTENTION: Vertical orientation requires careful attention to design details and panel layout so that all modules in the stack operate within their rated operating temperature range.

 

46 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Chapter 4

Install the Module

Topic

Page

Wire the Modules

48

Connection Details

50

Wiring Examples

51

See the POINT Guard I/O Safety Modules Installation Instructions, publication 1734-IN016, for information about terminal base installation and how to insert the I/O modules into the terminal bases.

Figure 25 POINT Guard I/O™ Modules

 

Module Locking Mechanism

Slide-in Writable Label I/O Module

Terminal Base

31867-M

 

Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 47

 

Install the Module

Wire the Modules Follow these guidelines when you wire the modules.

Do not route communication, input, or output wiring with conduit that contains high voltage. See the Industrial Automation Wiring and

Grounding Guidelines, publication1770-4.1.

Wire correctly after confirming the signal names of all terminals.

Use shielded cable for analog and tachometer inputs.

When using the sensor power supply on the 1734-IE4S module, do not connect an external power supply to the sensor.

If you use the 1734-IE4S sensor power supply of the module to power your input devices, you are responsible for verifying that your application

operates properly with the diagnostic features of this output.

Tighten screws for communication and I/O connectors correctly.

When using analog inputs, wire only to voltage or only to current inputs, not both. If you mix input types, it can induce noise on the input

measurements.

ATTENTION: Wire the POINT Guard I/O modules properly so that the 24V DC line does not touch the safety outputs accidentally or unintentionally.

Do not connect loads beyond the rated value to safety outputs.

Wire conductors correctly and verify operation of the module before placing the system into operation. Incorrect wiring can lead to loss of safety function.

Do not apply DC voltages that exceed the rated voltages to the module.

Do not connect a power source to the sensor power supply in the 1734-IE4S module or you could blow an internal fuse. When an internal fuse is blown, the module is inoperative.

Disconnect the module from the power supply before wiring. If wiring is performed while power is supplied, devices that are connected to the module can operate

unexpectedly.

WARNING: If you connect or disconnect wiring while the field-side power is on, an electric arc can occur. This arc could cause an explosion in hazardous location installations. Be sure that power is removed or the area is

nonhazardous before proceeding.

This equipment must be used within its specified ratings that Rockwell Automation has defined.

ATTENTION: This product is grounded through the DIN rail to chassis ground. Use zinc plated chromate-passivated steel DIN rail to assure proper grounding. The use of other DIN rail materials (for example, aluminum or plastic) that can corrode, oxidize, or are poor conductors, can result in improper or intermittent grounding. Secure DIN rail to mounting surface approximately every 200 mm (7.8 in.) and use endanchors appropriately. Be sure to ground the DIN rail

properly. Refer to Industrial Automation Wiring and Grounding Guidelines, Rockwell Automation publication 1770-4.1, for more information.

48 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Install the Module

Terminal Layout

These figures show the terminal layouts for the POINT Guard I/Omodules.

Figure 26 – 1734-IB8SField Connections

 

I0

0

I2

2

COM

/ 4 T0

6

I1

1

I3

3

COM

/ 5

T1M

7

I4

/ 0

I6

/ 2 COM

/ 4

T2

6

I5

1

I7

3

COM / 5 T3M

7

1734-TOP and 1734-TB Terminal Bases

Where:

T0 = Test Output 0

T1M = Test Output 1 with Muting T2 = Test Output 2

T3M = Test Output 3 with Muting I0…I7 = Inputs 0…7

COM = Supply Common

 

Figure 27 – 1734-OB8SField Connections

 

O0

0

O2

2

COM / 4 COM

6

O1

1

O3

3

COM

/ 5 COM

7

O4

/ 0 O6

/ 2

COM

/ 4

COM 6

O5

1

O7

3

COM / 5

COM 7

1734-TOP and 1734-TB Terminal Bases

Where:

O0…O7 = Safety Outputs 0…7 COM = Supply Common

 

Figure 28 – 1734-OBV2SField Connections

 

O0

O0

COM

V

O1

O1

COM

V

O2

O2

COM

V

O3

O3

COM

V

1734-TOP and 1734-TB Terminal Bases

Where:

ChannelsO0 andO1 = safety output bipolar pair ChannelsO2 andO3 = safety output bipolar pair

ChannelsO0 andO2 = sourcing outputs ChannelsO1 andO3 = sinking outputs COM = Sensor Power supply common V = Sensor Power supply

 

Figure 29 – 1734-IE4SField Connections

 

V0

I0

COM

S0

COM

S0

V1

I1

COM

S1

COM

S1

V2

I2

COM

S2

COM

S2

V3

I3

COM

S3

COM

S3

1734-TOP3 Terminal Base

Where:

V0…V3 = Voltage inputs 0…3 I0…I3 = Current inputs 0…3 COM = Supply Common

S0…S3 = Sensor power terminals

 

Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 49

 

Install the Module

Connection Details See the tables that show input device connection methods and their safety

categories.

Connected Device

Test Pulse from Test Output

Connection

Schematic Diagram

Safety

Category

Push Button

No

Connect the push button between 24V DC and I0.

24V DC

1

Yes

Connect the push button between I0 and T0. T0 must be configured as test pulse.

2

Emergency stop button Door monitor switch

No

Connect the devices between T0 and I0 and I1, note that T0 is configured for 24V power supply.

3

Connect the devices between 24V DC and I0 and I1.

24V DC

Yes

Connect the device between I0 and T0, and I1 and T1.

4

Light Curtain

Yes

Connect the OSSD1 and OSSD2 to I0 and I1, respectively. Connect the 24V power supply commons.

3 or 4 based on light curtain used

In

I0

I1

T0

T1

24V DC Com

OSSD2

OSSD1

50 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Install the Module

Wiring Examples Read this section for examples of wiring by application. See catalog number

details for the appropriate module.

Emergency Stop Dual-channel Devices

This example showshow to configure the controller and wire a digital

POINT Guard I/O module with an emergency stop button and gate monitoring switch that have dual-channel contacts. When used in combination with the

programs in a safety controller, this wiring is safety Category 4 (emergency stop button) and safety Category 3 (gate monitoring switch).

Figure 30 – 1734-IB8S POINT Guard I/OModule Wiring (Dual-channel Contacts)

1734-TB, 1734-TOP, 1734- TOP3 Bases Shown

Only with the 1734-TOP3 base.

Controller

Configuration

Parameter Name

Configuration Setting

Safety Input 0

Safety Input 0 Channel Mode

Test Pulse from Test Output

Safety Input 0 Test Source

Test Output 0

Dual-channel Safety Input 0/1 Mode

Dual-channel Equivalent

Dual-channel Safety Input 0/1 Discrepancy Time

100 ms (application dependent)

Safety Input 1

Safety Input 1 Channel Mode

Test Pulse from Test Output

Safety Input 1 Test Source

Test Output 1

Safety Input 2

Safety Input 2 Channel Mode

Safety Input

Safety Input 2 Test Source

Test Output 2

Dual-channel Safety Input 2/3 Mode

Dual-channel Equivalent

Safety Input 3

Safety Input 3 Channel Mode

Safety Input

Safety Input 3 Test Source

Test Output 3

Test Output 0

Test Output 0 Mode

Pulse Test Output

Test Output 1

Test Output 1 Mode

Pulse Test Output

Test Output 2

Test Output 2 Mode

Power Supply Output

Test Output 3

Test Output 3 Mode

Power Supply Output

Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 51

 

Install the Module

Single-channel Safety Contactor

This example showshow to configure the controller and wire a1734-OB8S

module with one safety contactor. When used in combination with the programs of the safety controller, this circuit configuration is safety Category 2.

Figure 31 1734-OB8S POINT Guard I/OModule Wiring (Single Safety Contact)

 

K1

M

Where:

O0…O7 = Safety Outputs COM = Common

 

Controller Configuration

Parameter Name

Configuration Setting

Safety Output 0

Safety Output 0 Point Mode

Safety Pulse Test

Point Operation Type

Single Channel

Dual-channel Safety Contactors

This example showshow to configure the controller and wire a 1734-OB8S

module with redundant safety contactors. When used in combination with the programs of the safety controller, this circuit configuration is safety Category 4. Additional wiring, such as monitoring feedback, can be required to achieve safety Category 4.

Figure 32 1734-OB8S POINT Guard I/OModule Wiring (Redundant Safety Contacts)

 

K1

K2

M

Where:

O0…O7 = Safety Outputs COM = Common

 

Controller

Configuration

Parameter Name

Configuration Setting

Safety Output 0

Safety Output 0 Point Mode

Safety Pulse Test

Point Operation Type

Dual-channel

Safety Output 1

Safety Output 1 Point Mode

Safety Pulse Test

52 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Install the Module

Bipolar Safety Outputs

These examples show how to wire a 1734-OBV2S output module with an input module to meet PLe and PLd safety requirements.

Figure 33 – 1734-OBV2S Dual Safety Output Wiring- PLe

 

K1

K2

M

K1

K2

 

Controller

Configuration

Parameter Name

Configuration Setting

Safety output 0

Safety output 0 point mode

Safety pulse test

Safety output 1

Safety output 1 point mode

Safety pulse test

Safety input 1

Safety input 1 point operation type

Single

Safety input 1 point mode

Safety pulse test

Safety input 1 test source

1

Test output 1

Test output 1 point mode

Pulse test

Figure 34 – 1734-OBV2S Dual Safety Output Wiring- PLd

 

K1

M

1734-OBV2S 1734-IB8S

O0

O0

COM

V

O1

O1

COM

V

O2

O2

COM

V

O3

O3

COM

V

I0

I2

COM

V

I1

I3

COM

T1M

 

Controller

Configuration

Parameter Name

Configuration Setting

Safety output 0

Safety output 0 point mode

Safety pulse test

Safety output 1

Safety output 1 point mode

Safety pulse test

Safety input 1

Safety input 1 point operation type

Single

Safety input 1 point mode

Safety pulse test

Safety input 1 test source

1

Test output 1

Test output 1 point mode

Pulse test

Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 53

 

Install the Module

Safety Analog Input Wiring

The following sections contain important guidelines for wiring safety analog

inputs and wiring examples for the 1734-IE4S module. See page 59 for examples.

Guidelines for Wiring Safety Analog Inputs

Follow these guidelines when wiring your safety analog inputs.

For eight terminal connections, use the 1734-TOP or 1734-TB terminal bases.

For all 12 terminal connections, use the 1734-TOP3 terminal base. When using a 1734-TOP3 base, both of the COM terminals and both of the

Sensor Power terminals for each channel are internally connected. The FE terminal connection that is shown on the diagrams represents a grounding lug on the panel or terminal connection to the DIN rail.

If the sensor has a digital output for use with Tachometer mode, it must be either a push-pull type output or have appropriate pull-up or pull-down resistors for NPNor PNP sensors. The analog input module does not

provide the low impedance of these pull-up or pull-down resistors.

IMPORTANT

You must verify the behavior of your 3-wire sensor to make sure that if it loses its ground connection, the signal is 0 (safe state) at the module input when the fault occurs.

IMPORTANT To obtainSIL 3,Cat. 3 or Cat.4, you must make sure that the analog input

signals do not short together or that the two sensors are installed to provide signals that are offset from one another. When the module is configured as the source for sensor power, a shortcircuit is detected at powerup (Cat. 2).

However, when an external power supply is used, another means must detect this fault.

54 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Install the Module

Safety Analog Input Wiring Examples

Follow the Guidelines for Wiring Safety Analog Inputs on page 54.

Figure 35 – 2-wire Current (4…20 mA) Sensor (SIL2 or SIL 3)

1734-TB Terminal Bases

SIL2 or SIL 3 2-wire Sensor

 

FE

Cable Shield

Grounding lug on the panel or terminal connection to the DIN rail

 

Figure 36 – 3-wire Voltage or Tachometer Sensor (SIL 2)

 

For analog voltage-output sensors, the signal levels for

operation for the application must be outside the signal level when the signal is not present, for example, when the wire is broken.

See the figures on page 59 for tachometer wiring detail.

1734-TB Terminal Bases

V0

I0

/

COM

S0

V1

I1

/

COM

S1

V2

I2

/

COM

S2

V3

I3

/

COM

S3

Grounding lug on the panel or terminal connection to the DIN rail

 

Figure 37 – 3-wire Current Sensor (SIL 2)

 

For 0…20 mA analog current-output sensors, the signal levels for operation for the application must be outside the signal level when the signal is not present, for example, when the wire is broken.

1734-TB Terminal Bases

V0

I0

COM

S0

V1

I1

/

COM

S1

V2

I2

/

COM

S2

V3

I3

COM

S3

Grounding lug on the panel or terminal connection to the DIN rail

 

Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 55

 

Install the Module

 

Signal Return and Common are at the same potential.

See the figures on page 59 for tachometer wiring detail.

Signal Return and Common are at the same potential.

Figure 38 – 4-wire Voltage or Tachometer Sensor (SIL 2)

1734-TOP3 Terminal Bases

V0

I0

COM

S0

COM

S0

V1

I1

COM

S1

COM

S1

V2

I2

COM

S2

COM

S2

V3

I3

COM

S3

COM

S3

Grounding lug on the panel or terminal connection to the DIN rail

Figure 39 – 4-wire Current Sensor (SIL 2)

1734-TOP3 Terminal Bases

V0

I0

/

COM

S0

COM

S0

V1

I1

/

COM

S1

COM

S1

V2

I2

/

COM

S2

COM

S2

V3

I3

/

COM

S3

COM

S3

Grounding lug on the panel or terminal connection to the DIN rail

 

Figure 40 – 2-wire Current (4…20 mA) Sensor (SIL 3)

1734-TB Terminal Bases

 

Field sensors are monitoring the same signal in a redundant configuration.

You must configure a safety deadband between the two signals to achieve SIL 3.

V0

I0

COM

S0

V1

I1

COM

S1

V2

I2

COM

S2

V3

I3

COM

S3

FE

Cable Shield Cable Shield

 

56 Rockwell Automation Publication 1734-UM013Q-EN-P April 2024

 

Install the Module

Figure 41 – 3-wire Voltage or Tachometer Sensor (SIL 3)

1734-TB Terminal Bases

 

This wiring configuration can also be used for SIL 2 redundant Tachometer mode.

For analog voltage-output sensors, the signal levels for

operation for the application must be outside the signal level when the signal is not present, for example, when the wire is broken.

Field sensors are monitoring the same signal in a redundant configuration.

You must configure a safety discrepancy deadband between the two signals to achieve SIL 3.

See the figures on page 59 for tachometer wiring detail.

V0

I0

/

COM

S0

V1

I1

/

COM

S1

V2

I2

/

COM

S2

V3

I3

/

COM

S3

FE

Cable Shield Cable Shield

 

Figure 42 – 3-wire Current Sensor (SIL 3)

 

For 0…20 mA analog current-output sensors, the signal levels for operation for the application must be outside the signal level when the signal is not present, for example, when the wire is broken.

Field sensors are monitoring the same signal in a redundant configuration.

You must configure a safety discrepancy deadband between the two signals to achieve SIL 3.

1734-TB Terminal Bases

V0

I0

COM

S0

V1

I1

COM

S1

V2

I2

/

COM

S2

V3

I3

/

COM

S3

Grounding lugs on the or terminal connections the DIN rail

Cable Shield

 

Figure 43 – 4-wire Voltage or Tachometer Sensor (SIL 3)

1734-TOP3 Terminal Bases

 

This wiring configuration may also be used for SIL 2 redundant Tachometer mode.

Signal Return and Common are at the same potential.

Field sensors are monitoring the same signal in a redundant configuration.

You must configure a safety discrepancy deadband between the two signals to achieve SIL 3.

See the figures on page 59 for tachometer wiring detail.

V0

I0