Why Choose the ABB CM-ESS.2P Voltage Monitoring Relay?
The ABB CM-ESS.2P is a compact and reliable single-phase AC/DC voltage monitoring relay designed to detect overvoltage and undervoltage conditions in industrial electrical systems. As part of the ABB CM-ESS measuring and monitoring relay series, it provides accurate voltage supervision for electrical control panels, industrial machinery and automation equipment, helping protect connected systems against abnormal voltage conditions.
This relay uses a True RMS (TRMS) measuring principle to monitor AC and DC voltages across four selectable measuring ranges. Its configurable overvoltage and undervoltage monitoring functions, adjustable hysteresis and selectable tripping delay provide flexible protection and signalling for industrial control applications. Front-mounted adjustment controls and LED indicators simplify configuration and operating status monitoring.
With a wide 24–240 V AC/DC control supply, four measuring ranges covering 3–600 V AC/DC and two changeover (SPDT) output contacts rated at 250 V / 4 A, the CM-ESS.2P offers versatile voltage monitoring for industrial electrical installations. Its compact 22.5 mm-wide DIN rail housing and maintenance-free Easy Connect push-in terminals allow straightforward integration into control cabinets and automation systems.
Key Advantages
- Reliable overvoltage and undervoltage monitoring for single-phase AC/DC circuits.
- Wide 24–240 V AC/DC control supply range for flexible industrial integration.
- Four selectable voltage measuring ranges covering 3–600 V AC/DC.
- True RMS voltage measurement for dependable monitoring of AC and DC voltages.
- Selectable overvoltage or undervoltage monitoring to suit different protection requirements.
- Adjustable 3–30% hysteresis helps prevent unwanted relay switching near the threshold.
- Configurable instantaneous or 0.1–30 s tripping delay for application-specific response.
- Two changeover output contacts for alarm signalling and control circuit integration.
- Maintenance-free Easy Connect push-in terminals simplify wiring and installation.
- Compact 22.5 mm DIN rail design saves valuable control panel space.
Key Features
- ABB CM-ESS.2 single-phase voltage monitoring relay series.
- 24–240 V AC/DC rated control supply voltage.
- AC and DC voltage monitoring using True RMS measurement.
- Four selectable measuring ranges: 3–30 V, 6–60 V, 30–300 V and 60–600 V.
- Configurable overvoltage or undervoltage monitoring.
- 3–30% adjustable hysteresis relative to the selected threshold.
- Adjustable tripping delay: 0 s or 0.1–30 s.
- 2 changeover (SPDT) output contacts.
- 250 V / 4 A output contact rating.
- Open-circuit operating principle for relay switching.
- Three LED indicators for operational status indication.
- Front-mounted controls for voltage threshold, hysteresis and timing adjustments.
- Easy Connect Technology with maintenance-free push-in terminals.
- Optional sealable transparent cover to help prevent unauthorised adjustment.
- 22.5 mm housing width for compact control cabinet installation.
- Tool-free mounting and removal from a DIN rail.
- Housing material with UL 94 V-0 fire protection classification.
Technical Specifications
- Manufacturer: ABB
- Series: CM-ESS.2 Voltage Monitoring Relays
- Model: CM-ESS.2P
- ABB order code: 1SVR740830R0400
- Product group: Measuring & Monitoring Relays
- Product type: Single-phase AC/DC voltage monitoring relay
- Monitoring function: Overvoltage or undervoltage monitoring
- Rated control supply voltage: 24–240 V AC/DC
- Measuring principle: True RMS (TRMS)
- Measuring range 1: 3–30 V AC/DC
- Measuring range 2: 6–60 V AC/DC
- Measuring range 3: 30–300 V AC/DC
- Measuring range 4: 60–600 V AC/DC
- Hysteresis adjustment: 3–30%
- Tripping delay: 0 s or 0.1–30 s
- Output contacts: 2 changeover (SPDT)
- Output contact rating: 250 V / 4 A
- Operating principle: Open-circuit principle
- Terminal type: Screwless push-in terminals
- Connection technology: ABB Easy Connect Technology
- Status indication: 3 LED indicators
- Mounting type: DIN rail mounting
- Housing width: 22.5 mm
- Dimensions (H × W × D): 85.6 × 22.5 × 103.7 mm
- Net weight: Approximately 0.142 kg
- Operating ambient temperature: −20 to +60 °C
- Storage temperature: −40 to +85 °C
- Housing material classification: UL 94 V-0
- EAN: 4016779852401
Reliable Voltage Monitoring for Industrial Electrical Systems
Voltage monitoring relays such as the ABB CM-ESS.2P continuously supervise an electrical voltage and compare the measured value against a configured threshold. When the voltage exceeds or falls below the selected limit, the relay changes the state of its output contacts according to the configured operating mode and tripping delay. This allows connected control equipment to respond to abnormal supply conditions, reducing the risk of equipment malfunction and unexpected process interruptions.
The CM-ESS.2P is designed for industrial automation engineers, electrical panel builders and maintenance professionals requiring flexible AC/DC voltage supervision. Its four measuring ranges, adjustable hysteresis and selectable delay provide precise configuration for different applications, while its dual changeover contacts allow integration with contactors, PLC inputs, alarm circuits and supervisory control systems. The compact DIN rail construction and push-in terminals simplify installation and maintenance in modern industrial control panels.
Typical Applications
- Overvoltage and undervoltage monitoring in industrial electrical installations.
- Voltage supervision for single-phase AC and DC control circuits.
- Industrial machinery and automation control panels.
- Power supply monitoring for PLCs and electronic control equipment.
- Electrical distribution and protection systems.
- Alarm signalling for abnormal voltage conditions.
- Monitoring of DC power supplies and battery-supported control circuits.
- Voltage supervision in pump and motor control systems.
- Manufacturing and process automation equipment.
- OEM electrical assemblies requiring configurable voltage monitoring.
