ABB CM-WDS 1SVR430896R0000 Cycle Monitoring Relay

The ABB CM-WDS (1SVR430896R0000) monitoring relay delivers dependable cycle-monitoring and watchdog functionality for industrial automation systems. It constantly watches input pulse patterns and triggers output if pulses stop or deviate beyond set timing parameters. In addition, its compact design and DIN-rail mounting allow clean installation in control cabinets where space is limited. This relay ensures critical processes maintain safe operation when signals or cycles are interrupted.

2. Functional Highlights / Key Benefits

• Continuously verifies that a regularly intermittent input pulse is present, enabling early detection of signal loss or failure. 

• Offers selectable cycle-monitoring time ranges from 0.5 ms up to 1000 ms, giving flexibility to match pulse frequency requirements for many systems. 

• Provides one changeover output (SPDT / 1 c/o) contact rated at 250 V, 4 A — sufficient to drive downstream control logic or alarm circuits. 

• Works on 24 V DC control supply, which matches standard automation control voltages and simplifies wiring. 

• Screw-terminal connection and compact 22.5 mm width allow smooth integration into existing DIN-rail systems without complex rewiring. 

3. Technical Data / Specifications

Electrical & Functional Data

• Control supply voltage: 24 V DC 

• Output contact: 1 c/o (SPDT) contact rated 250 V AC / 4 A 

• Function: Cycle monitoring (watchdog) — monitors pulse input for continuity and consistency 

• Monitoring time ranges: 0.5 ms to 1000 ms (4 selectable ranges) 

Mechanical / Mounting Data

• Mounting: DIN-rail (standard industrial mounting) 

• Dimensions (W × H × D): 22.5 mm × 78 mm × 100 mm 

• Net weight: approximately 0.163 kg 

• Terminals: Screw terminals for easy wiring 

Compliance / Additional Features

• Conforms to relevant low-voltage switch technology standards under ETIM classification. 

• Accessory option: sealable transparent cover to prevent unauthorized adjustments. 

4. Typical Applications / System Integration Use Cases

The CM-WDS relay is ideal for automation systems that rely on regular pulse signals — for instance motor drive feedback loops, conveyor systems, or batching equipment requiring heartbeat monitoring. It also supports safety or supervisory circuits by triggering alarms or shutdowns when a pulse sequence stops unexpectedly. In addition, OEM control panels, machine guard systems, or remote I/O racks benefit from this watchdog feature to detect failure of sensors or communication pulses. Its compact DIN-rail form factor simplifies retrofits and upgrades in existing installations, even where space is restricted.

5. Reliability and Maintenance / Service Considerations

ABB designed the CM-WDS for robust long-term performance under industrial conditions. Its screw-terminal connections and standardized DIN-rail form reduce mechanical stress and simplify maintenance or replacement. Because of the built-in watchdog and cycle-monitoring logic, the relay can significantly reduce unplanned downtime by catching pulse failures early. In addition, the optional sealable cover helps protect settings against accidental or unauthorized changes, which aids in compliance and system integrity. Therefore, operators gain both reliability and traceability in critical control applications.

6. FAQ

Q1: What does the CM-WDS relay monitor?
It monitors for a regularly intermittent input pulse and activates output contact when pulses stop or deviate.

Q2: What is the control voltage for this relay?
The relay operates on 24 V DC control supply.

Q3: What are the selectable monitoring time ranges?
It supports 4 selectable ranges from 0.5 milliseconds up to 1000 milliseconds.

Q4: What kind of output contact does it provide?
It delivers one change-over contact (SPDT / 1 c/o), rated at 250 V AC / 4 A.

Q5: Where is this relay typically mounted?
It mounts on standard DIN-rail, suitable for industrial control cabinets and automation panels.

Q6: Can I protect the settings from unauthorized changes?
Yes — there is an optional transparent sealable cover accessory to prevent unwanted adjustments.