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ABB CM-SRS.21S current monitoring relay 1SVR730841R1400 with a 220–240 V AC control supply, selectable 3 mA–1 A RMS measuring ranges, configurable overcurrent or undercurrent monitoring, adjustable tripping delay and two changeover contacts.
£125.93
The ABB CM-SRS.21S is a compact single-phase current monitoring relay designed for reliable overcurrent or undercurrent supervision in industrial control and automation systems. With ABB order code 1SVR730841R1400, this CM-SRS series relay operates from a 220–240 V AC control supply and monitors both AC and DC currents using an RMS measuring principle.
The CM-SRS.21S provides three selectable measuring ranges of 3–30 mA, 10–100 mA and 0.1–1 A. It can be configured for either overcurrent or undercurrent monitoring, with adjustable hysteresis from 3–30% of the selected threshold value to provide stable switching behaviour for a wide range of current-supervision applications.
Two changeover (SPDT) output contacts rated at 250 V / 4 A provide flexible interfacing with PLC inputs, contactors, alarms and interlocking circuits. An adjustable ON-delay tripping time of 0 or 0.1–30 s, screw connection technology and a compact 22.5 mm housing make the CM-SRS.21S well suited to DIN-rail control-panel installations.
Current monitoring relays enable industrial control systems to identify electrical loads operating above or below defined current limits. The ABB CM-SRS.21S can be configured for overcurrent or undercurrent supervision, making it suitable for detecting overload, underload, loss of load and other current-dependent operating conditions.
Its three selectable RMS measuring ranges enable supervision from 3 mA up to 1 A. Adjustable hysteresis provides stable switching around the selected threshold, while the adjustable tripping delay can help prevent brief current variations from causing unnecessary alarm, control or shutdown actions.
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| Time Delay | Adjustable | |
|---|---|---|
| Monitored Supply | Single-phase | |
| Signal / Input Range | 3–30 mA | |
| Monitoring Function | Current | |
| Series | CM-SRS | |
| ABB order code | 1SVR730841R1400 | |
| Product type | Single-phase current monitoring relay | |
| Monitoring function | Overcurrent or undercurrent | |
| Rated control supply voltage | 220–240 V AC | |
| Measuring range 1 | 3–30 mA | |
| Measuring range 2 | 10–100 mA | |
| Measuring range 3 | 0.1–1 A | |
| Measuring principle | RMS for AC and DC currents | |
| Hysteresis | Adjustable 3–30% of threshold value | |
| Tripping delay | 0 or 0.1–30 s, ON-delay | |
| Output | 2 c/o (SPDT) contacts | |
| Output contact rating | 250 V / 4 A | |
| Operating principle | Open-circuit principle | |
| Terminal type | Screw terminals | |
| Protection rating | IP50 housing / IP20 terminals | |
| Mounting | DIN rail | |
| Operating temperature | -20 to +60 °C | |
| Storage temperature | -40 to +85 °C | |
| Width | 22.5 mm | |
| Height | 85.6 mm | |
| Depth | 103.7 mm | |
| Net weight | 0.179 kg | |
| EAN | 4016779852340 |
The ABB CM-SRS.21S is used for configurable overcurrent or undercurrent monitoring of AC and DC currents in industrial electrical and automation systems.
This exact CM-SRS.21S variant operates from a rated control supply of 220–240 V AC.
The relay provides three selectable measuring ranges: 3–30 mA, 10–100 mA and 0.1–1 A.
Yes. The relay provides an adjustable ON-delay of 0 or 0.1–30 s, allowing short-duration current conditions to be accommodated where required.
The CM-SRS.21S provides two changeover (SPDT) output contacts rated at 250 V / 4 A for integration with control, alarm and signalling circuits.
ABB CM-SRS monitoring relays provide dependable current supervision for industrial automation and electrical control applications, combining RMS AC/DC measurement, adjustable switching parameters and compact DIN-rail installation.
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