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ABB CM-MPS.31S (1SVR730884R1300) multifunctional three-phase monitoring relay for 160–300 V AC line-to-line supplies, featuring phase failure, selectable phase sequence, overvoltage, undervoltage and phase unbalance monitoring, adjustable tripping delay from 0 to 30 seconds, two changeover contacts and screw terminals for industrial electrical control applications.
£156.87
The ABB CM-MPS.31S (1SVR730884R1300) is a multifunctional three-phase monitoring relay designed to supervise electrical supply conditions in industrial machinery, motor control systems and power distribution installations. Part of ABB's CM-MPS measuring and monitoring relay range, it provides dependable detection of phase failure, incorrect phase sequence, overvoltage, undervoltage and phase unbalance.
The CM-MPS.31S operates directly from the monitored three-phase supply, with a rated control supply and measuring voltage of 160–300 V AC between phases (L-L) at 50/60 Hz. Its adjustable voltage and phase unbalance thresholds allow engineers to configure the monitoring response according to the operating requirements of the installation.
Featuring two changeover (SPDT) output contacts rated at 250 V / 4 A, selectable phase sequence monitoring and an adjustable tripping delay of 0 s or 0.1–30 s, the CM-MPS.31S provides flexible fault signalling for industrial control systems. Its compact 22.5 mm DIN rail housing, screw terminals and front-mounted controls make it suitable for electrical control panels where reliable supply supervision and straightforward commissioning are essential.
The ABB CM-MPS.31S continuously supervises the condition of a three-phase electrical supply and provides switching signals when abnormal voltage or phase conditions are detected. Its monitoring functions help identify electrical supply faults that could otherwise lead to machinery malfunction, motor damage or unexpected process interruptions.
Phase failure monitoring detects the loss of a supply phase, while phase sequence monitoring identifies an incorrect phase rotation. Phase sequence supervision is particularly useful in applications involving three-phase motors, pumps, fans and compressors, where incorrect phase rotation may cause equipment to operate in the wrong direction.
The relay also provides overvoltage and undervoltage monitoring with adjustable thresholds. This allows engineers to define acceptable operating limits for the monitored electrical supply and receive a relay output signal when the measured voltage moves outside those limits.
Phase unbalance monitoring detects excessive differences between phase voltages. Voltage unbalance can affect three-phase equipment performance and may contribute to increased heating or reduced efficiency in connected motors. The CM-MPS.31S provides an additional layer of supervision by identifying abnormal phase voltage relationships.
The CM-MPS.31S is intended for three-phase systems with line-to-line voltages from 160–300 V AC. It is powered directly by the monitored circuit, making it convenient for installations where a separate auxiliary control supply is not available.
The ABB CM-MPS.31S provides a selectable instantaneous tripping setting of 0 s or an adjustable delay from 0.1–30 s. This allows the monitoring response to be configured according to the requirements of the electrical installation.
For applications where immediate fault signalling is required, the relay can be configured without an intentional tripping delay. Where brief supply fluctuations are expected, a suitable delay may help reduce unnecessary switching caused by short-duration voltage disturbances.
The relay supports selectable ON-delayed and OFF-delayed tripping behaviour, providing additional flexibility when integrating its outputs into industrial control systems. The device also incorporates a 200 ms start-up delay.
With two changeover (SPDT) output contacts rated at 250 V / 4 A, the CM-MPS.31S can provide switching signals to PLC inputs, alarm circuits, contactors and other compatible industrial control devices.
The relay is intended for electrical monitoring and control signalling. It does not replace appropriately selected short-circuit protection, motor overload protection or other protective devices required by the installation.
The CM-MPS.31S features a compact 22.5 mm housing width, allowing efficient use of space inside industrial electrical cabinets. Its DIN rail mounting arrangement supports straightforward installation alongside other control and protection components.
The relay uses screw terminals with double-chamber cage connections, providing secure electrical connections for the monitored three-phase supply and relay output circuits.
Front-mounted adjustment controls allow engineers to configure the monitoring functions, voltage thresholds and tripping delay during commissioning. An optional sealable transparent cover can be fitted to help prevent unauthorised changes to the configured settings.
For industrial installations requiring dependable phase failure detection, phase sequence supervision and voltage monitoring, the ABB CM-MPS.31S offers a compact and versatile monitoring solution.
Tick the specs you need, then view products that match.
| Monitoring Function | Three-phase supply | |
|---|---|---|
| Monitored Supply | Three-phase | |
| Signal / Input Range | 3 × 160–300 V AC | |
| Time Delay | Adjustable |
The ABB CM-MPS.31S is a multifunctional three-phase monitoring relay used to detect phase failure, incorrect phase sequence, overvoltage, undervoltage and phase unbalance. It provides relay output signals for industrial control, alarm and equipment protection applications.
The CM-MPS.31S, ABB order code 1SVR730884R1300, operates from a three-phase supply with line-to-line voltages of 160–300 V AC at 50/60 Hz. The relay is powered directly by the monitored electrical supply.
No. The CM-MPS.31S is designed to monitor the three-phase supply through the L1, L2 and L3 connections. Its rated measuring voltage is specified between phases, so a neutral connection is not required for its standard monitoring arrangement.
Yes. The relay provides phase failure detection and changes its output state when the monitored supply conditions meet the configured fault criteria. This helps identify the loss of a phase in industrial three-phase systems.
Yes. The CM-MPS.31S includes selectable phase sequence monitoring. When enabled, it can detect incorrect phase rotation, helping protect equipment that depends on the correct order of the three-phase supply.
Yes. The relay provides adjustable overvoltage and undervoltage monitoring. It compares the monitored line-to-line voltages with the configured thresholds and provides a switching response when the applicable fault conditions are detected.
Yes. The CM-MPS.31S includes phase unbalance detection, allowing it to identify excessive differences between the monitored phase voltages. This supports early identification of abnormal supply conditions that may affect connected equipment.
The relay provides an instantaneous 0 s setting or an adjustable tripping delay from 0.1–30 s. Selectable ON-delayed and OFF-delayed operation allows the timing response to be configured for the application.
The CM-MPS.31S features two changeover (SPDT) output contacts rated at 250 V / 4 A. These contacts can be used for compatible PLC inputs, contactor control circuits and industrial alarm signalling.
Both models provide the same basic three-phase monitoring functions and a 160–300 V AC line-to-line measuring range. The main difference is the terminal technology: the CM-MPS.31S uses screw terminals, while the CM-MPS.31P uses push-in terminals.
No. The CM-MPS.31S is specified for 160–300 V AC between phases. A nominal 400 V AC line-to-line supply exceeds this range. A monitoring relay with a suitable higher voltage rating should be selected instead.
The relay uses screw terminals with double-chamber cage connections. These provide secure connections for the monitored three-phase supply and the relay output circuits.
The relay is designed for DIN rail mounting inside industrial electrical control panels, motor control centres and distribution cabinets. Its compact 22.5 mm housing width helps conserve installation space.
ABB CM-MPS three-phase monitoring relays provide dependable electrical supply supervision for industrial machinery, motor control and power distribution applications. With phase failure detection, selectable phase sequence monitoring, adjustable voltage and phase unbalance thresholds, configurable tripping delays and two changeover contacts, the CM-MPS.31S offers a practical solution for identifying abnormal three-phase supply conditions. Its 160–300 V AC line-to-line measuring range, screw terminals and compact DIN rail housing make it suitable for industrial control systems requiring reliable three-phase monitoring.
Technical reference: ABB product catalogue – 1SVR730884R1300. Verify the current ABB technical documentation and installation instructions before commissioning.
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