Clearwater Tech Logo

ABB Low Voltage

Home   >   Products   >   ABB   >   CM-IWN.4/5/6   >   Insulation   >   Monitoring   >   Relays

ABB Low Voltage Controls

The CM-IWN serves to monitor insulation resistance in accordance with IEC 61557-8 in unearthed IT AC systems, IT AC systems with galvanically connected DC circuits, or unearthed IT DC systems with a voltage up to 400 V AC and 600 V DC. The measuring range can be extended up to 690 V AC and 1000 V DC by using the coupling unit CM-IVN. It can be configured to the requirements of the applications and therefore used multi-functional.

ABB CM-IWN.4/5/6 Insulation Monitoring Relays Distributors

CM-IWN.4/5/6 Range

All devices are available with two different terminal versions. You can choose between the proven screw connection technology (double-chamber cage connection terminals) and the completely tool-free Easy Connect Technology (push-in terminals).

Both the Easy Connect Technology with push-in terminals and screw connection technology with double-chamber cage connection terminals have the same connection geometry as well as terminal position.

The CM-IWN serves to monitor insulation resistance in accordance with IEC 61557-8 in unearthed IT AC systems, IT AC systems with galvanically connected DC circuits, or unearthed IT DC systems.

If you are looking for ABB CM-IWN.4/5/6 Insulation Monitoring Relays, please call us on (844) 331-9372 or email us at we will do our best to help you find the ABB measuring relays that you are looking for at competitive prices. If you are searching for ABB monitoring relay technical information (data-sheets) please use the datasheets or product selection guide page links.


  • For monitoring the insulation resistance of unearthed IT systems up to Un = 400 V AC and 600 V DC
  • According to IEC/EN 61557-8 "Electrical safety in low voltage distribution systems up to 1000 V a.c. and 1500 V d.c. - Equipment for testing, measuring or monitoring of protective measures - Part 8: Insulation monitoring devices for IT systems"1)
  • Specifically for applications with high system leakage capacitances, for example in photovoltaic environments
  • Rated control supply voltage 24-240 V AC/DC
  • Prognostic measuring principle with superimposed square wave signal
  • Two measuring ranges 1-100 kΩ and 2-200 kΩ
  • One (1 x 2 c/o) or two (2 x 1 c/o) threshold values Ran1/R11) (warning) and Ran2/R22) (prewarning) configurable3)
  • Precise adjustment of the threshold values in 1 kΩ steps (R1) and 2 kΩ steps (R2)
  • Interrupted wire detection configurable
  • Non-volatile fault storage configurable
  • Open- or closed-circuit principle configurable
  • Precise adjustment by front-face operating controls
  • Screw connection technology or Easy Connect Technology available

The insulation resistance between system lines and system earth is measured. If this falls below the adjustable threshold values, the output relays switch into the fault state. The device can monitor control circuits (single-phase) and main circuits (3-phase). Supply systems with voltages Un = 0-400 V AC (15-400 Hz) or 0-600 V DC can be directly connected to the measuring inputs and their insulation resistance being monitored. For systems with voltages above 400 V AC and 600 V DC the coupling unit CM-IVN can be used for the expansion of the CM-IWN voltage range.

A pulsating measuring signal is fed into the system to be monitored and the insulation resistance calculated. This pulsating measuring signal alters its form depending on the insulation resistance and system leakage capacitance. From this altered form the change in the insulation resistance is forecast.

When the forecast insulation resistance corresponds to the insulation resistance calculated in the next measurement cycle and is smaller than the set threshold value, the output relays are activated or deactivated, depending on the device configuration. This measuring principle is also suitable for the detection of symmetrical insulation faults.

In addition, the unearthed AC-, DC- or AC/DC system is monitored for inadmissible system leakage capacitance. If the system leakage capacitance is too high, the output relays switch to the fault state. Also incorrect settings that could cause a faulty function of the device are monitored. When the device detects such an incorrect setting, the output relays switch to the fault state.

Our industrial factory automation supplies distributors warehouse in Boise, Idaho stocks some ABB Products enabling us to further assist you in finding the correct CM-IWN.4 relay for your application in the USA, Canada and Mexico. Whether we have insulation monitors in stock in Boise, Idaho or need to get them from ABB; Clearwater Tech can get CM-IWN.4/5/6 insulation monitoring relays to you fast and save money! It will be very helpful if you have the CM-IWN.5 relays part numbers ready, then our sales representatives can provide you with a pricing and availability quote for insulation monitor that you are looking for in seconds. If you do not have the part numbers for ABB CM-IWN.6, our application engineers will be able to help you figure out the part numbers and get the price quote to you as soon as possible.

Stock Check

Part No:

Search Tips
Can't find a part number?
E-mail Us!

Contrinex RFID

Contrinex has developed a range of high frequency RFID components which are compatible with ISO/IEC 15693. Consequently, Contrinex read/write modules may communicate with all compliant tags, i.e. not only with those offered by Contrinex. Standard as well as high-performance all-metal transponders are a Contrinex specialty. They permit operation in particularly difficult operating conditions. Very rugged smooth cylindrical

Panasonic PLC

There Are 2 Types of Windows based 32 bit programming software available. FPWIN-GR, easy programming with powerful features and FPWIN-PRO, IEC61131 based object oriented programming. FP2SH is a compact PLC series W140 x H100 x D110 mm W5.51 x H3.94 x D4.33 in (when using 5-module type) loaded with multiple functions, achieving superior cost performance. The CPU units have an RS232C port as standard equipment,