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  • Insulation monitoring device for mobile generators
  • Protective isolation with insulation monitoring and shutdown
  • In Accordance with DIN VDE 0100-551 and DIN EN 61557-8
  • Two Response values (Factory settings 46 kΩ, 23 kΩ)

The ISOMETER® monitors the insulation resistance of unearthed AC, AC/DC and DC systems (IT systems) with nominal system voltages of 3(N)AC, AC/DC 0…400 V or DC 0…400 V.

The maximum permissible system leakage capacitance Ce is 5 μF. DC components existing in AC systems do not influence the operating characteristics, when a minimum load current of DC 10 mA flows. A separate supply voltage allows de-energised systems to be monitored, too.

  • Features
  • Applications
  • Accessories
  • Ordering information
  • Downloads
  • Monitoring the insulation resistance for unearthed AC/DC systems
  • Measurement of the system voltage (true r.m.s.) with undervoltage and overvoltage detection
  • Measurement of DC system voltages to earth (L1+/PE and L2-/PE)
  • Two operating modes: GEn and DC
  • Automatic adaptation to the system leakage capacitance up to 5 μF
  • Selectable start-up delay, response delay and delay on release
  • Two separately adjustable response value ranges of 5…200 kΩ (Alarm 1, Alarm 2)
  • Alarm signalling via LEDs (AL1, AL2), a display and alarm relays (K1, K2)
  • Automatic device self test with connection monitoring
  • Selectable N/C or N/O relay operation
  • Measured value indication via multi-functional LCD
  • Fault memory can be activated
  • RS-485 (galvanically isolated) including the following protocols:
    - BMS interface (Bender measuring device interface) for data exchange with other Bender components
    - Modbus RTU
    - IsoData (for continuous data output)
  • Password protection to prevent unauthorised parameter changes
  • AC main circuits up to 400 V
  • DC main circuits up to 400 V
  • Generators according to DIN VDE 0100-551


Mandatory accessories for ISOMETER® isoGEN423

TypeArt. No.
Mounting clip for screw mounting (1 piece per device)B98060008

Variants of ISOMETER® isoGEN423

TypeVersionArt. No.
isoGEN423-D4-4Push-wire terminalB71036325
isoGEN423-D4W-4Push-wire terminalB71036325W

Downloads for ISOMETER® isoGEN423



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