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ISOMETER® IR155-4210

ISOMETER® IR155-4210

  • Insulation monitoring device (IMD) for unearthed DC charging systems (IT systems) for DC charging stations according CCS standard
  • Continuous measurement of the insulation resistance 0…10 MΩ, factory-set preconfigured response values
  • IT systems up to 0…800 V
  • Short-circuit protected driver outputs for fault detection and PWM coded Iso measuring value
  • Power supply suitable for 12 V and 24 V systems

The ISOMETER® IR155-4210 monitors the insulation resistance between the insulated and active HV-conductors of an DC charging station according CCS standard (Un = DC 0…800 V) and PE. The patented measurement technology is used to monitor the condition of the insulation on the DC side as well as on the AC motor side of the electrical drive/charger system. Existing insulations faults will be signalised reliably even under high system interferences which can be caused by motor/charger control processes, etc.


  • Suitable for 12 V and 24 V systems
  • Automatic device self test
  • Response time < 2 s after power on for first estimated insulation resistance (SST)
    – Response time < 10 s for measured insulation resistance (AMP)
  • Automatic adaptation to the existing system leakage capacitance (≤1 μF)
  • Detection of earth faults and interruption of the earth line
  • Insulation monitoring of AC and DC insulation faults for unearthed systems (IT systems) 0…800 V
  • Undervoltage detection for voltages below 500 V (adjustable at factory by Bender)
  • Short-circuit proof outputs for:
    – Fault detection (high-side output)
    – Measured value (PWM 5…95 %) and status (f = 10…50 Hz) at high or inverted low-side driver (MHS output)
  • Conformal coating (SL1301ECO-FLZ)
  • UL 2231 compliant


  • Monitoring for unearthed DC charging systems (IT systems) for electric vehicles

ISOMETER® IR155-4210 Variant(s)

Type Art.No
IR155-4210Fixed default parameters
Ran: 100 kΩ
Under voltage detection: 0 V (inactive)
Measurement output high side
IR155-4210Parameters can be customised
Ran: 100…200 kΩ
Under voltage detection: 0…500 V
Fave: 1…10
Measurement output high side

Optional Accessories for ISOMETER® IR155-4210

TypeArt. No
Mounting kitB91068500
Connecting kit IR155-42xxB91068502

Downloads for ISOMETER® IR155-4210

CE Declarations of conformity IR155-32xx 83.9 KB 2022/08/12 06:17:2412.08.2022 06:17:24
Datasheets IR155-4210 582.4 KB EN2022/06/09 10:54:3809.06.2022 10:54:38D00377
Quickstarts IR155-xx10 1.1 MB EN2021/07/23 09:42:2723.07.2021 09:42:27D00376