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1SVR730841R0400 ABB CM-SRS.21S Current Monitoring Relay 110–130 V AC
ABB CM-SRS.21S current monitoring relay 1SVR730841R0400 with a 110–130 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
Why Choose the ABB CM-SRS.21S Current Monitoring Relay?
The ABB CM-SRS.21S is a compact and reliable single-phase current monitoring relay designed for overcurrent or undercurrent supervision in industrial control and automation systems. With ABB order code 1SVR730841R0400, this CM-SRS series relay operates from a 110–130 V AC control supply and provides RMS measurement of both AC and DC currents.
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, while adjustable hysteresis from 3–30% of the selected threshold value enables stable switching behaviour matched to the requirements of the application.
The relay provides two changeover (SPDT) output contacts rated at 250 V / 4 A and 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 particularly suitable for DIN-rail installation in industrial control panels.
Key Advantages
- Reliable overcurrent or undercurrent monitoring for industrial electrical systems.
- 110–130 V AC control supply for compatible industrial control circuits.
- Three selectable measuring ranges covering 3 mA to 1 A.
- RMS measuring principle supports AC and DC current monitoring.
- Adjustable 3–30% hysteresis for stable threshold switching.
- Adjustable 0 or 0.1–30 s tripping delay helps accommodate transient current conditions.
- Two changeover (SPDT) output contacts provide flexible control and signalling.
- Compact 22.5 mm-wide housing conserves DIN-rail space.
Key Features
- ABB CM-SRS single-phase current monitoring relay series.
- 110–130 V AC rated control supply voltage.
- Configurable overcurrent or undercurrent monitoring.
- Selectable 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 ON-delay tripping time.
- 2 c/o (SPDT) relay outputs.
- 250 V / 4 A contact rating.
- Open-circuit operating principle.
- Screw connection technology with double-chamber cage terminals.
- Compact DIN-rail mounting format.
Reliable Current Monitoring for Industrial Systems
Current monitoring relays allow industrial control systems to detect 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 excessive load, 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 control or alarm actions.
Typical Applications
- Industrial control and automation panels.
- AC and DC current supervision.
- Machine load and operating-state monitoring.
- Motor and actuator control circuits.
- Pump and fan monitoring systems.
- Heating element and electrical load supervision.
- Alarm, signalling and interlocking circuits.
- OEM machinery and production equipment.
Technical Specifications
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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 | 1SVR730841R0400 | |
| Product type | Single-phase current monitoring relay | |
| Monitoring function | Overcurrent or undercurrent | |
| Rated control supply voltage | 110–130 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 | |
| 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 | 4016779852302 |
Frequently Asked Questions
What is the ABB CM-SRS.21S 1SVR730841R0400 used for?
The ABB CM-SRS.21S is used for configurable overcurrent or undercurrent monitoring of AC and DC currents in industrial electrical and automation systems.
What supply voltage does the CM-SRS.21S require?
ABB order code 1SVR730841R0400 operates from a rated control supply of 110–130 V AC.
What current ranges can the CM-SRS.21S monitor?
The relay provides three selectable measuring ranges: 3–30 mA, 10–100 mA and 0.1–1 A.
Does the CM-SRS.21S include an adjustable tripping delay?
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.
How many output contacts does the CM-SRS.21S provide?
The CM-SRS.21S provides two changeover (SPDT) output contacts rated at 250 V / 4 A for integration with control and signalling circuits.
Trusted ABB Monitoring Technology
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.
