Why Choose the ABB CM-SRS.M1S Current Monitoring Relay?
The ABB CM-SRS.M1S is a multifunctional single-phase current monitoring relay designed for dependable overcurrent and undercurrent supervision in industrial control and automation systems. With ABB order code 1SVR730840R0600, this CM-SRS series relay operates from a wide 24–240 V AC/DC control supply and provides RMS measurement of both AC and DC currents.
The CM-SRS.M1S provides three selectable measuring ranges of 3–30 mA, 10–100 mA and 0.1–1 A. Its multifunction design allows selection of overcurrent or undercurrent monitoring, open- or closed-circuit operating principle and latching or non-latching operation. Adjustable hysteresis from 3–30% of the threshold value provides further flexibility when configuring the relay for a particular application.
The relay features two changeover (SPDT) output contacts and adjustable start-up and tripping delays of 0 or 0.1–30 s. Screw terminals, a compact 22.5 mm housing and DIN-rail mounting make the CM-SRS.M1S easy to integrate into industrial control panels where flexible current supervision and reliable signalling are required.
Key Advantages
- Multifunctional overcurrent and undercurrent monitoring in one compact relay.
- Wide 24–240 V AC/DC control supply supports diverse industrial applications.
- Three selectable RMS measuring ranges covering 3 mA to 1 A.
- Suitable for monitoring both AC and DC currents.
- Selectable open- or closed-circuit operating principle.
- Selectable latching or non-latching operation.
- Adjustable 3–30% hysteresis for stable threshold switching.
- Adjustable 0 or 0.1–30 s start-up and tripping delays.
- Two changeover contacts provide flexible control and signalling options.
Key Features
- ABB CM-SRS multifunction current monitoring relay series.
- 24–240 V AC/DC rated control supply voltage.
- Selectable overcurrent or undercurrent monitoring.
- Measuring ranges of 3–30 mA, 10–100 mA and 0.1–1 A.
- RMS measuring principle for AC and DC currents.
- 3–30% adjustable hysteresis.
- 0 or 0.1–30 s adjustable start-up delay.
- 0 or 0.1–30 s adjustable ON-delay tripping time.
- Selectable latching function.
- Selectable open- or closed-circuit operating principle.
- 2 c/o (SPDT) relay outputs.
- Screw connection technology for secure field wiring.
Flexible Current Monitoring for Industrial Systems
Current monitoring relays allow control systems to detect when electrical loads operate above or below defined current limits. The ABB CM-SRS.M1S combines overcurrent and undercurrent monitoring with selectable operating and latching modes, making it suitable for detecting overload, underload, loss-of-load and other current-dependent operating conditions.
Adjustable start-up and tripping delays allow short-duration conditions such as starting currents to be accommodated without unnecessary switching. Combined with adjustable hysteresis and two changeover outputs, this provides flexible integration with contactors, alarms, PLC inputs and machine control circuits.
Typical Applications
- Industrial control and automation panels.
- AC and DC current supervision.
- Motor load and underload monitoring.
- Pump and fan operating-state monitoring.
- Machine and process control systems.
- Heating element and electrical load supervision.
- Alarm, signalling and interlocking circuits.
- OEM machinery and production equipment.
