Why Choose the ABB CM-IWN.1P Insulation Monitoring Relay?
The ABB CM-IWN.1P is a high-performance insulation monitoring relay designed for continuous supervision of insulation resistance in unearthed electrical distribution systems. As part of the ABB CM-IWN insulation monitoring relay series, it provides reliable detection of insulation deterioration and earth faults in industrial AC, DC and combined AC/DC electrical networks.
This multifunctional insulation monitoring relay helps improve electrical safety, equipment availability and preventive maintenance by identifying insulation faults before they develop into more serious electrical problems. The CM-IWN.1P features adjustable insulation resistance thresholds, configurable output contacts, fault memory functionality and interrupted measuring-wire detection. Its advanced measuring principle uses a superimposed square-wave signal to monitor insulation resistance in unearthed IT systems.
With a 24–240 V AC/DC control supply, two selectable insulation resistance measuring ranges of 1–100 kΩ and 2–200 kΩ, and compatibility with unearthed networks up to 400 V AC or 600 V DC, the CM-IWN.1P is suitable for industrial power distribution, machinery, control systems and electrical installations requiring dependable insulation supervision. Its compact DIN rail-mounted design and push-in connection terminals simplify installation inside electrical control panels.
Key Advantages
- Reliable insulation resistance monitoring for unearthed AC, DC and mixed AC/DC electrical systems.
- 24–240 V AC/DC universal control supply provides flexibility across industrial applications.
- Suitable for unearthed electrical networks up to 400 V AC or 600 V DC.
- Two selectable measuring ranges of 1–100 kΩ and 2–200 kΩ for adjustable insulation monitoring.
- Early detection of insulation deterioration and earth faults helps improve electrical safety and operational reliability.
- Configurable two changeover relay contacts support fault signalling and control system integration.
- Selectable non-volatile fault memory retains fault information when required.
- Configurable interrupted-wire detection improves monitoring circuit supervision.
- Advanced measuring principle with a superimposed square-wave signal.
- Push-in terminals enable fast, secure and maintenance-free electrical connections.
- Compact DIN rail-mounted construction saves space in industrial control cabinets.
Key Features
- ABB CM-IWN insulation monitoring relay series.
- 24–240 V AC/DC rated control supply voltage.
- Monitoring of insulation resistance in unearthed IT electrical networks.
- 0–400 V AC / 0–600 V DC monitored system voltage.
- Suitable for unearthed AC, DC and galvanically connected AC/DC systems.
- Two selectable insulation resistance measuring ranges: 1–100 kΩ and 2–200 kΩ.
- Adjustable insulation resistance response thresholds.
- Maximum system leakage capacitance of 20 µF.
- Two configurable changeover contacts for alarm and fault signalling.
- Configurable open-circuit or closed-circuit operating principle.
- Selectable non-volatile fault storage.
- Configurable interrupted measuring-wire detection.
- Superimposed square-wave measuring principle.
- LED indicators for operating and fault status.
- Push-in connection terminals using ABB Easy Connect Technology.
- DIN rail mounting for industrial electrical panels.
- Insulation monitoring functionality in accordance with IEC 61557-8.
Technical Specifications
- Manufacturer: ABB
- Series: CM-IWN Insulation Monitoring Relays
- Model: CM-IWN.1P
- ABB order code: 1SVR760660R0200
- Product type: Insulation monitoring relay
- Product group: Measuring & Monitoring Relays
- Rated control supply voltage: 24–240 V AC/DC
- Monitored system voltage: 0–400 V AC / 0–600 V DC
- Supported network types: Unearthed AC, DC and mixed AC/DC IT systems
- Insulation resistance measuring range 1: 1–100 kΩ
- Insulation resistance measuring range 2: 2–200 kΩ
- Maximum system leakage capacitance: 20 µF
- Measuring circuit frequency: 15–400 Hz
- Measuring principle: Superimposed square-wave signal
- Monitoring function: Insulation resistance and earth fault monitoring
- Output contacts: 2 changeover contacts (2 c/o)
- Output configuration: 2 × 1 c/o or 1 × 2 c/o, configurable
- Contact current rating: 4 A
- Fault memory: Configurable non-volatile fault storage
- Wire interruption detection: Configurable
- Operating principle: Open-circuit or closed-circuit, configurable
- Connection technology: Push-in screwless terminals
- Mounting type: DIN rail mounting
- Housing protection rating: IP50
- Terminal protection rating: IP20
- Operating ambient temperature: −25 to +60 °C
- Storage temperature: −40 to +85 °C
- Dimensions (H × W × D): 85.6 × 45 × 104.8 mm
- Net weight: 0.217 kg
- EAN: 4016779852661
- Applicable standard: IEC 61557-8
Reliable Insulation Monitoring for Unearthed Electrical Systems
Insulation monitoring relays such as the ABB CM-IWN.1P continuously supervise the insulation resistance between active conductors and earth in unearthed electrical networks. When insulation resistance falls below a configured threshold, the relay provides an output signal that can activate an alarm, initiate a control response or notify maintenance personnel of a developing insulation fault.
Unlike conventional earth fault protection devices used in earthed distribution systems, insulation monitoring devices are specifically designed for unearthed IT electrical networks. These systems can often continue operating after an initial insulation fault, making early fault detection particularly important for maintaining process availability and preventing subsequent electrical failures.
The CM-IWN.1P uses a superimposed square-wave measuring signal to monitor insulation resistance in AC, DC and mixed AC/DC systems. Its selectable measuring ranges, configurable relay outputs and non-volatile fault memory provide flexibility for industrial applications where continuous electrical supervision and dependable fault signalling are required.
For systems operating above the relay's standard monitored voltage range, the compatible ABB CM-IVN.P coupling unit can extend the monitored network voltage capability up to 690 V AC or 1000 V DC when installed according to ABB specifications.
Typical Applications
- Unearthed IT electrical distribution systems.
- Industrial AC and DC power supply networks.
- Electrical insulation resistance monitoring in industrial machinery.
- Manufacturing and automated production facilities.
- Industrial motor control centres and electrical control cabinets.
- Emergency power supply and backup electrical systems.
- Industrial battery-backed DC distribution networks.
- Process control and continuous-operation industrial installations.
- Electrical fault detection and preventive maintenance systems.
- Power distribution systems requiring continuous insulation supervision.
- OEM electrical equipment and industrial automation panels.
