Why Choose the ABB CM-PBE Phase Loss Monitoring Relay with Neutral Monitoring?
The ABB CM-PBE (1SVR550881R9400) is a compact and dependable phase loss monitoring relay with neutral monitoring, designed to supervise electrical supplies in industrial control and automation systems. Part of the ABB CM-PBE monitoring relay range, this version detects phase failure in three-phase networks and supports neutral monitoring, helping protect equipment against abnormal supply conditions.
Designed for 380–440 V AC phase-to-phase and 220–240 V AC phase-to-neutral electrical systems, the CM-PBE monitors the connected supply and provides a switching signal when a significant voltage loss is detected. Its fixed monitoring threshold and automatic reset behaviour make it a practical solution for motor starter circuits, electrical distribution panels and industrial machinery.
The relay is powered directly by the monitored circuit, eliminating the need for a separate auxiliary supply. With one normally open output contact, a yellow relay status LED and a compact 22.5 mm DIN rail-mounted housing, the ABB CM-PBE provides straightforward installation and reliable supply supervision for compatible single-phase and three-phase applications.
Key Advantages
- Reliable phase loss monitoring for industrial electrical systems.
- Integrated neutral monitoring for compatible three-phase, four-wire supplies.
- Supports 380–440 V AC phase-to-phase electrical networks.
- Designed for 220–240 V AC phase-to-neutral monitoring.
- Can also monitor suitable single-phase electrical supplies using the manufacturer-specified terminal arrangement.
- Self-powered operation requires no separate auxiliary control supply.
- Fixed phase failure detection threshold simplifies installation and commissioning.
- One normally open relay output enables integration with contactors, alarms and control systems.
- Closed-circuit operating principle allows the output relay to release when a monitored fault occurs.
- 500 ms start-up delay and 150 ms tripping delay provide defined response times.
- Automatic re-energisation after the monitored supply returns to acceptable conditions.
- Integrated yellow LED provides clear relay status indication.
- Compact 22.5 mm housing width saves space in electrical control panels.
- Helps reduce machinery downtime associated with phase loss and significant supply voltage faults.
Key Features
- ABB CM-PBE phase monitoring relay series.
- Phase failure detection with neutral monitoring.
- 380–440 V AC phase-to-phase measuring range.
- 220–240 V AC phase-to-neutral measuring range.
- 50/60 Hz rated supply frequency.
- Monitors three-phase supplies through L1, L2, L3 and N terminals.
- Suitable for single-phase monitoring when connected according to ABB instructions.
- Phase failure detection at approximately 60% of nominal voltage.
- Fixed monitoring threshold with automatic recovery.
- One normally open (SPST-NO) output contact.
- 250 V AC / 4 A contact rating.
- Closed-circuit operating principle.
- 500 ms fixed start-up delay.
- 150 ms fixed tripping delay.
- Yellow LED for output relay status indication.
- Screw-terminal connections for supply monitoring and output wiring.
- DIN rail mounting for industrial control cabinets.
- Compact housing dimensions of 78 × 22.5 × 78.5 mm.
- Designed for integration into industrial motor control and electrical distribution systems.
Technical Specifications
- Manufacturer: ABB
- Series: CM-PBE Three-Phase Monitoring Relays
- Model: CM-PBE
- ABB order code: 1SVR550881R9400
- ABB product group: 310921-Measuring & Monitoring Relays
- Product type: Phase loss monitoring relay
- Monitoring functions: Phase failure detection and neutral monitoring
- Rated control supply voltage: 3 × 380–440 V AC phase-to-phase; 220–240 V AC phase-to-neutral
- Phase-to-phase measuring range: 380–440 V AC
- Phase-to-neutral measuring range: 220–240 V AC
- Supply frequency: 50/60 Hz
- Supply type: Alternating current (AC)
- Monitored conductors: L1, L2, L3 and N
- Neutral monitoring: Yes
- Single-phase monitoring capability: Yes, with manufacturer-specified terminal connections
- Auxiliary supply: Not required; powered by measuring circuit
- Phase failure detection threshold: Below approximately 60% of nominal voltage
- Monitoring threshold adjustment: Fixed
- Output contacts: 1 normally open contact
- Contact configuration: SPST-NO (1 n/o)
- Output terminals: 13 and 14
- Output contact rating: 250 V AC / 4 A
- Operating principle: Closed-circuit principle
- Start-up delay: 500 ms
- Tripping delay: 150 ms
- Reset behaviour: Automatic after acceptable supply conditions return
- Status indication: 1 yellow LED
- Terminal type: Screw terminals
- Mounting type: DIN rail mounting
- Dimensions (H × W × D): 78 × 22.5 × 78.5 mm
- Net weight: 0.066 kg
- EAN: 4013614350498
- RoHS compliance: Following EU Directive 2011/65/EU
- Application category: Industrial phase loss and neutral supply monitoring
Reliable Phase Loss and Neutral Monitoring for Industrial Automation
Industrial motors and electrical control systems depend on the availability of their intended supply conductors for dependable operation. A missing phase can reduce motor torque, increase current in the remaining windings and lead to overheating or equipment shutdown. The ABB CM-PBE phase loss monitoring relay provides a practical means of detecting significant supply loss and signalling the associated control system.
This version of the CM-PBE monitors L1, L2, L3 and neutral in compatible three-phase electrical networks. When the required supply conditions are present, the output relay energises after its fixed start-up delay and the yellow LED indicates the energised state. If a phase failure is detected, the relay releases after its fixed tripping delay, allowing the connected control circuit to respond.
The CM-PBE uses a phase failure threshold of approximately 60% of nominal voltage. It is intended to detect significant voltage loss rather than provide adjustable precision overvoltage or undervoltage supervision. The relay does not monitor phase sequence, so applications requiring detection of incorrect phase rotation should use an appropriate phase sequence monitoring device.
The neutral-monitoring version, ABB order code 1SVR550881R9400, also supports suitable single-phase supply monitoring. For this application, ABB specifies that the three phase input terminals are linked together and connected to the monitored phase conductor, with the neutral connected to its designated terminal. Installation must follow the applicable ABB connection diagram.
Its closed-circuit operating principle enables the normally open output contact to remain closed while the relay is energised under acceptable supply conditions. When a monitored fault causes the relay to de-energise, the contact opens. This signal can be incorporated into a motor starter, contactor control circuit or automation system to initiate a protective response. The relay is a monitoring device and does not directly interrupt the main supply to a motor.
Typical Applications
- Three-phase electrical supply phase loss monitoring.
- Three-phase systems requiring neutral monitoring.
- Industrial motor starter and contactor control circuits.
- Electrical distribution boards and industrial switchgear.
- Pumps and industrial pumping equipment.
- Fans, blowers and ventilation systems.
- Industrial compressors and refrigeration machinery.
- Conveyor and material handling systems.
- Automated manufacturing and packaging machinery.
- Single-phase supply monitoring with the specified terminal configuration.
- Industrial control panels requiring phase failure signalling.
- OEM machinery and electrical automation installations.
