Why Choose the ABB CM-PVS.31P Three-Phase Monitoring Relay?
The ABB CM-PVS.31P (1SVR740794R1300) is an industrial three-phase monitoring relay designed to supervise the quality and availability of three-phase AC power supplies. Part of ABB's CM-PVS measuring and monitoring relay range, it combines phase failure detection, selectable phase sequence monitoring, adjustable overvoltage monitoring and adjustable undervoltage monitoring in one compact device.
Designed for a 160–300 V AC line-to-line measuring and supply range, the CM-PVS.31P is powered directly from the monitored three-phase circuit, eliminating the need for a separate auxiliary power supply. Its independently adjustable upper and lower voltage thresholds provide greater flexibility than fixed-threshold monitoring relays, allowing the device to be configured for the voltage limits required by the installation.
The relay uses a true RMS (TRMS) measuring principle and provides an adjustable 0 s or 0.1–30 s tripping delay, with selectable ON-delayed or OFF-delayed operation. With two changeover (SPDT) contacts rated at 250 V / 4 A, three LED status indicators, ABB Easy Connect push-in terminals and a compact 22.5 mm DIN rail housing, the CM-PVS.31P is well suited to industrial motor control, machinery and electrical distribution applications.
Key Advantages
- Comprehensive three-phase monitoring in a single compact relay.
- Phase failure detection helps identify loss of a supply phase.
- Selectable phase sequence monitoring helps detect incorrect phase rotation.
- Adjustable overvoltage threshold for high-voltage supervision.
- Adjustable undervoltage threshold for low-voltage supervision.
- 160–300 V AC line-to-line range for compatible three-phase systems.
- True RMS measurement for effective AC voltage evaluation.
- Self-powered operation from the monitored three-phase supply.
- Two changeover (SPDT) output contacts rated at 250 V / 4 A.
- Adjustable tripping delay from 0.1–30 s, or instantaneous operation.
- Selectable ON-delayed or OFF-delayed tripping for flexible fault response.
- Three LED indicators for operating status and fault indication.
- Easy Connect push-in terminals simplify installation.
- 22.5 mm DIN rail housing conserves control cabinet space.
- Suitable for industrial and appropriate railway-related applications, subject to system requirements.
- Optional sealable transparent cover helps protect configured settings.
Key Features
- ABB CM-PVS.31P three-phase monitoring relay.
- Manufacturer order code: 1SVR740794R1300.
- Rated control supply and measuring voltage: 3 × 160–300 V AC.
- Measured voltage: Line-to-line across L1, L2 and L3.
- Rated frequency: 50/60 Hz.
- Monitoring functions: Phase failure, phase sequence, overvoltage and undervoltage.
- Overvoltage threshold: Adjustable.
- Undervoltage threshold: Adjustable.
- Phase sequence monitoring: Can be switched off.
- Measuring principle: True RMS (TRMS).
- Supply arrangement: Powered by the monitored circuit.
- Start-up delay: 200 ms.
- Tripping delay: 0 s or 0.1–30 s.
- Tripping mode: ON-delayed or OFF-delayed.
- Output configuration: 2 changeover (SPDT) contacts.
- Contact rating: 250 V / 4 A.
- Status indication: 3 LEDs.
- Terminal technology: ABB Easy Connect push-in terminals.
- Mounting: DIN rail.
- Housing width: 22.5 mm.
- Operating ambient temperature: −25 to +60 °C.
- Optional sealable transparent protective cover.
Technical Specifications
- Manufacturer: ABB
- Product series: CM-PVS
- Model: CM-PVS.31P
- ABB order code: 1SVR740794R1300
- ABB product group: 310921-Measuring & Monitoring Relays
- Product type: Three-phase monitoring relay
- Rated control supply voltage: 3 × 160–300 V AC
- Rated measuring voltage: 3 × 160–300 V AC
- Line-to-line measuring range: 160–300 V AC
- Rated frequency: 50/60 Hz
- Supply and measuring terminals: L1, L2, L3
- Separate auxiliary supply: Not required
- Measuring principle: True RMS (TRMS)
- Phase failure monitoring: Yes
- Phase sequence monitoring: Selectable
- Overvoltage monitoring: Yes
- Undervoltage monitoring: Yes
- Upper voltage threshold: Adjustable as an absolute value
- Lower voltage threshold: Adjustable as an absolute value
- Start-up delay: 200 ms
- Tripping delay: 0 s or 0.1–30 s
- Tripping delay modes: ON-delayed or OFF-delayed
- Output contacts: 2 changeover (SPDT)
- Output contact rating: 250 V / 4 A
- UL/CSA contact rating: B300
- Maximum UL/CSA output operating voltage: 300 V AC
- Rated insulation voltage, input to output: 600 V
- Rated insulation voltage, between output circuits: 300 V
- Status indication: 3 LEDs
- Terminal type: Easy Connect push-in terminals
- Connection technology: Screwless spring-clamp connection
- Housing protection rating: IP50
- Terminal protection rating: IP20
- Housing flammability classification: UL 94 V-0
- 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
- Product net weight: Approximately 0.132 kg
- EAN: 4016779852012
- Customs tariff number: 85364900
Reliable Three-Phase Supply Monitoring
The ABB CM-PVS.31P continuously supervises the electrical conditions of a compatible three-phase AC supply. By monitoring the voltages between L1, L2 and L3, it helps identify abnormal conditions that may affect connected machinery and industrial equipment.
Phase failure monitoring detects the loss of a supply phase. This is particularly important for three-phase motors, where a missing phase can result in reduced torque, abnormal current distribution, increased heating and possible equipment damage.
Phase sequence monitoring helps detect incorrect phase rotation. Incorrect phase rotation may cause motors to operate in the wrong direction, which can be problematic for pumps, fans, conveyors, compressors and other direction-sensitive machinery.
The phase sequence function can be disabled where phase rotation monitoring is not required, providing additional flexibility during commissioning.
In addition to phase-related faults, the CM-PVS.31P supervises overvoltage and undervoltage, helping detect supply conditions outside the configured acceptable operating range.
Adjustable Overvoltage and Undervoltage Thresholds
One of the main advantages of the CM-PVS.31P is its ability to monitor voltage using adjustable upper and lower thresholds.
Unlike fixed-threshold three-phase monitoring relays, the CM-PVS.31P allows the overvoltage and undervoltage limits to be set as absolute voltage values within the device's specified range.
The relay is designed for 160–300 V AC line-to-line systems. The selected thresholds should reflect the acceptable operating voltage limits of the connected equipment and the requirements of the complete electrical installation.
When the monitored voltage rises above the upper threshold or falls below the lower threshold, the relay provides a switching response according to the selected tripping delay and operating configuration.
This adjustable-threshold design is particularly useful where equipment requires tighter voltage supervision or where a fixed ±10% tolerance would not be suitable.
True RMS Voltage Measurement
The CM-PVS.31P uses a true RMS measuring principle to evaluate the monitored AC voltages.
True RMS measurement considers the effective value of the AC voltage waveform rather than relying solely on its peak value. This provides a suitable basis for voltage supervision in industrial electrical systems.
The measuring and control supply are derived from the same three-phase circuit, so the relay does not require a separate auxiliary power connection.
The CM-PVS.31P is intended for three-phase AC systems with line-to-line voltages within 160–300 V. It should not be used directly on higher-voltage networks outside its rated measuring and supply range.
Adjustable Tripping Delay for Flexible Fault Response
The ABB CM-PVS.31P features an adjustable tripping delay that can be switched off for 0 s operation or set between 0.1 and 30 s.
This allows the relay's response to be tailored to the installation. Where rapid fault signalling is required, an instantaneous setting can be selected. Where brief voltage disturbances are expected, an appropriate delay may help prevent unnecessary switching.
The device also supports selectable ON-delayed or OFF-delayed tripping, allowing the switching behaviour to be configured for the monitoring application.
A 200 ms start-up delay is included in the relay's operating characteristics.
These timing functions help the CM-PVS.31P integrate with industrial control circuits, but the delay setting must be selected carefully where the monitored equipment is sensitive to voltage or phase faults.
Two Changeover Contacts for Industrial Control Integration
The CM-PVS.31P provides two changeover (SPDT) output contacts rated at 250 V / 4 A.
These contacts can be used to provide switching signals to compatible motor control circuits, PLC inputs, industrial alarms and other electrical monitoring equipment.
The availability of two changeover contacts allows the monitored supply condition to be integrated into more than one suitable control or signalling circuit, subject to the applicable electrical ratings.
The CM-PVS.31P is a monitoring relay and does not replace correctly rated motor protection circuit breakers, short-circuit protective devices or other equipment required by the installation.
Easy Connect Push-In Terminals and Compact DIN Rail Installation
The ABB CM-PVS.31P uses Easy Connect Technology, featuring screwless push-in terminals that simplify electrical panel wiring.
The spring-clamp connection system provides secure, maintenance-free electrical connections when installed using compatible conductors and ABB's recommended wiring procedures.
With dimensions of 85.6 × 22.5 × 103.7 mm, the relay occupies only 22.5 mm of DIN rail width, helping conserve space in industrial control cabinets.
Three LED indicators provide convenient information about operating and output states. Front-mounted adjustment controls allow configuration of the voltage thresholds, phase sequence monitoring and tripping delay.
An optional sealable transparent cover is available to help prevent unauthorised changes to the configured settings.
Typical Applications
- Three-phase voltage monitoring in 160–300 V AC line-to-line systems.
- Phase failure detection in industrial motor control circuits.
- Phase sequence monitoring for rotation-sensitive equipment.
- Adjustable overvoltage supervision in electrical control panels.
- Adjustable undervoltage detection in industrial installations.
- Industrial motor control centres and automation cabinets.
- Pump motor supply monitoring.
- Fan and ventilation machinery.
- Compressor control systems.
- Conveyor and material handling equipment.
- Manufacturing and processing machinery.
- Industrial electrical distribution equipment.
- PLC-based supply fault signalling and alarm systems.
- OEM machinery requiring adjustable voltage limits.
- Compatible railway electrical systems, subject to application requirements.
- Control panels requiring compact push-in terminal monitoring relays.
