Allen-Bradley 440R-M23143 Guardmaster MSR138DP Safety Relay, 24V DC, 3NO Delayed Outputs
Allen-Bradley 440R-M23143 is a Guardmaster safety relay (type MSR138DP) with three normally open delayed safety outputs, a 24 V DC control supply and an adjustable time delay for controlled rundown of machines that cannot stop immediately.
Overview
The 440R-M23143 provides time-delayed safety output contacts adjustable over a 0.15 to 3 second range, letting rotating machinery (spindles, fans, centrifuges) coast to a safe speed before power is fully removed. A 15 ms response time, 7 A rated thermal current on screw terminals and 2500 V rated impulse withstand give it headroom for demanding control circuits, while the 45 mm wide IP40 housing mounts on a 35 mm DIN rail.
Key Features
- Safety relay with 3 N.O. delayed (time-delayed) safety outputs
- Adjustable time delay range 0.15…3 s
- 24 V DC rated control supply voltage
- Response time 15 ms; recovery time 100 ms
- Rated thermal current 7 A; switching current 10 mA minimum
- Input resistance 135 ohm; impulse withstand 2500 V
- Screw connection terminals; wire size 0.2 to 2.5 mm²
- IP40, NEMA 1 enclosure; 45 mm wide; 35 mm DIN rail mount
Technical Specifications
| Attribute | Value |
|---|---|
| Manufacturer | Allen Bradley (Rockwell Automation) |
| Product Line | Guardmaster Safety Relays (440R) |
| Part Number / Catalog No. | 440R-M23143 |
| UPC | 611320826753 |
| Product Type | Safety Relay with Delayed Outputs (MSR138DP) |
| Rated Control Supply Voltage | 24 V DC |
| Safety Outputs | 3 N.O., time-delayed |
| Time Delay Range | 0.15 to 3 s adjustable |
| Response Time | 15 ms |
| Recovery Time | 100 ms |
| Power ON Delay | 1 ms |
| Rated Thermal Current | 7 A |
| Minimum Switching Current | 10 mA |
| Input Resistance | 135 Ohm |
| Rated Impulse Withstand Voltage | 2500 V |
| Type of Electrical Connection | Screw Connection |
| Wire Size | 0.2 to 2.5 mm² |
| Enclosure Type | IP40, NEMA 1 |
| Enclosure Width | 45 mm |
| Dimensions | 13 x 13 x 6 cm (5.1 x 5.1 x 2.4 in) |
| Weight | 0.31 lbs (0.14 kg) |
Applications
The 440R-M23143 is designed for machines with an inertia overrun — grinding spindles, mixers, saws and centrifuges — where the guard may be opened before the machine has stopped, and safety outputs must hold power until the adjustable delay has elapsed.
Why Buy from Us
This safety relay is available new in original factory packaging, fully tested and backed by a standard warranty of 1 year. We ship worldwide with careful protective packaging and fast dispatch. Quantity discounts and repair/exchange options are available on request.
Documents
| Resource | Title | Link |
|---|---|---|
| Publication | 440R-IN088 — Guardmaster Configurable Safety Relay / MSR138DP Installation Instructions (English) | 440r-in088_-en-p.pdf |
| Publication | 440R-TD001 — Guardmaster Safety Relays Technical Data (English) | 440r-td001_-en-p.pdf |
| Publication | 440R-UM003 — Guardmaster Safety Relays User Manual (English) | 440r-um003_-en-p.pdf |
| Data Sheet | MSR138DP Safety Relay Specification Sheet | MSR138DP.PDF |
