Why Choose the ABB CM-MPS.31S Three-Phase Monitoring Relay?
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.
Key Advantages
- Multifunctional three-phase monitoring in one compact industrial relay.
- Detects phase failure and abnormal three-phase supply conditions.
- Selectable phase sequence monitoring helps identify incorrect phase rotation.
- Adjustable overvoltage and undervoltage thresholds support application-specific monitoring.
- Phase unbalance detection helps identify excessive differences between phase voltages.
- 160–300 V AC line-to-line supply and measuring range.
- Powered directly by the monitored electrical supply, eliminating the need for a separate auxiliary supply.
- Two changeover (SPDT) contacts rated at 250 V / 4 A.
- Adjustable tripping delay: instantaneous or 0.1–30 s.
- Selectable ON-delayed or OFF-delayed tripping behaviour.
- 200 ms start-up delay for controlled relay initialisation.
- Front-mounted adjustment controls simplify configuration and commissioning.
- Secure screw terminals with double-chamber cage connections.
- Compact 22.5 mm DIN rail housing conserves control cabinet space.
- Suitable for motor control, machinery protection and industrial fault signalling.
- Optional sealable transparent cover helps prevent unauthorised changes to settings.
Key Features
- ABB CM-MPS.31S multifunctional three-phase monitoring relay.
- Manufacturer order code: 1SVR730884R1300.
- Rated control supply voltage: 160–300 V AC, line-to-line.
- Three-phase measuring range: 3 × 160–300 V AC.
- Rated supply frequency: 50/60 Hz.
- Monitoring functions: Phase failure, phase sequence, overvoltage, undervoltage and phase unbalance.
- Selectable phase sequence monitoring.
- Adjustable voltage and phase unbalance thresholds.
- Start-up delay: 200 ms.
- Tripping delay: 0 s or 0.1–30 s.
- Selectable ON-delayed or OFF-delayed tripping.
- Output configuration: 2 changeover (SPDT) contacts.
- Output contact rating: 250 V / 4 A.
- Terminal technology: Screw terminals with double-chamber cage connections.
- Front-mounted configuration controls.
- DIN rail mounting for industrial control cabinets.
- Housing width: 22.5 mm.
- Optional sealable transparent protective cover.
Technical Specifications
- Manufacturer: ABB
- Product series: CM-MPS
- Model: CM-MPS.31S
- ABB order code: 1SVR730884R1300
- ABB product group: 310921-Measuring & Monitoring Relays
- Product type: Multifunctional three-phase monitoring relay
- Rated control supply voltage: 160–300 V AC, line-to-line (L-L)
- Measuring voltage: 3 × 160–300 V AC, line-to-line
- Rated frequency: 50/60 Hz
- Supply arrangement: L1-L2-L3
- Auxiliary supply: Supplied by the monitored circuit
- Phase failure monitoring: Yes
- Phase sequence monitoring: Selectable
- Overvoltage monitoring: Yes
- Undervoltage monitoring: Yes
- Phase unbalance monitoring: Yes
- Threshold adjustment: Adjustable voltage and phase unbalance thresholds
- Start-up delay: 200 ms
- Tripping delay: 0 s or adjustable 0.1–30 s
- Delay configuration: ON-delayed or OFF-delayed
- Output contacts: 2 changeover (SPDT) contacts
- Contact rating: 250 V / 4 A
- UL/CSA contact rating: B300
- Maximum output operating voltage (UL/CSA): 300 V AC
- Rated insulation voltage: 600 V for input/output circuits; 300 V between output circuits
- Terminal type: Screw terminals
- Terminal construction: Double-chamber cage connections
- Terminal tightening torque: Approximately 0.8 N·m
- Housing protection rating: IP50
- Terminal protection rating: IP20
- Mounting type: DIN rail mounting
- Operating ambient temperature: −25 to +60 °C
- Storage temperature: −40 to +85 °C
- Dimensions (H × W × D): 85.6 × 22.5 × 103.7 mm
- Net weight: 0.142 kg
- EAN: 4016779851855
- Customs tariff number: 85364900
Reliable Three-Phase Supply Monitoring and Equipment Protection
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.
Adjustable Tripping Delay and Industrial Control Integration
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.
Compact DIN Rail Installation and Straightforward Commissioning
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.
Typical Applications
- Three-phase electrical supply monitoring in industrial installations.
- Phase failure detection in motor control circuits.
- Phase sequence monitoring for rotation-sensitive equipment.
- Overvoltage and undervoltage supervision in electrical distribution systems.
- Phase unbalance monitoring in three-phase networks.
- Industrial motor control centres and machinery panels.
- Pump, fan and compressor control systems.
- Conveyor and material handling equipment.
- Manufacturing and production machinery.
- Industrial electrical distribution boards.
- PLC-based supply fault signalling and alarm systems.
- OEM machinery requiring integrated three-phase monitoring.
- Electrical maintenance and power quality supervision.
- Control cabinets requiring compact DIN rail monitoring devices.
