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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6 Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024
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 |
Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 7
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. |
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.
8 Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024
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.
Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 9
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
Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 11
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
• 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.
12 Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024
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.
Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 15
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
16 Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024
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.
Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 17
POINT Guard I/O Overview
Notes:
18 Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024
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 undercurrent–current, which could indicate a problem with the components of the sensor.
• Channel–to–channel 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.
34 Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024
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 UL–compliant applications, the 1734-IB8S, 1734-OB8S, and 1734-OBV2S modules, and all connected I/O, must be powered from a SELV– or PELV–compliant power source that is rated 150VA maximum. For UL–compliant applications, the 1734-IE4S module, the module’sfield 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 SELV–and PELV–compliant, 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 |
Rockwell Automation Publication 1734-UM013Q-EN-P – April 2024 41
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 end–anchors 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 short–circuit 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 |