Dold Industries Ltd

11 Hamberts Rd. Blackall Ind. Estate
South Woodham Ferrers
GB-Essex, CM3 5UW
RN 5897/300

Insulation monitor

RN 5897/300


Auxiliary voltage

Alarm value

Prewarning value

Approvals and Markings


  • 0066942
  • RN5897.12/300/61 AC/DC24-60V
The insulation monitor RN 5897/300 of the VARIMETER IMD family provides best and up to date... more

Product description

The insulation monitor RN 5897/300 of the VARIMETER IMD family provides best and up to date insulation monitoring of modern IT systems in an optimum and state of the art way fulfilling the relevant standards. The device can be used in the most flexible way for AC, DC and AC/DC systems. The adjustment of the setting values is simple and user friendly done on 3 rotary switches on the front of the device. Via multicolor LED the device status is indicated easy to read. With a sealable transparent cover the device is protectet against manipulation.

Technical specifications

Width: 52,5 mm
Classification: For mobile power generators
Response value: 10 - 250 kΩ
IMD type: AC, DC, AC/DC
Nominal voltage IT system: AC 0 - 230, DC 0 - 230 V
Auxiliary voltage: DC, AC/DC
Earth fault indicator: Yes
Approvals: UL
Response value type: Adjustable
Enclosure design: Distribution board
Type: RN 5897/300


  • For mobile generator sets according to DIN VDE 0100-551
  • Preventive fire and system protection
  • Detection of symmetric and asymmetric insulation faults
  • Universal application in non-earthed AC, DC, AC/DC networks up to max. 300 V
  • Easy adjustment of response values and setting parameter via rotational switch
  • Suitable for large leakage capacitances up to 30 μF
  • Monitoring also with voltage-free mains
  • Measuring circuit L(+)/L(-) with broken wire detection (can be switched off)
  • Protective conductor PE1/PE2 with broken wire detection (can't be switched off)
  • No additional coupling device required


  • Insulation monitoring according to IEC/EN 61557-8
  • 2 separate adjustable response thresholds (using e.g. for pre-Alarm and Alarm)
  • Setting range of 1st response value (Pre-Alarm): 20 kΩ … 1 MΩ:
  • Setting range of 2nd response value (Alarm): 10 kΩ … 250 kΩ
  • 2 changeover contacts für insulation failures-Pre-Alarm and -Alarm
  • Energized or de-energized on trip can be selected for indicator relay
  • LED for status indication
  • Automatic and manual device self-test
  • Alarm storage selectable
  • Protection against manipulation by sealable transparent cover
  • External control input for combined Test-/Reset-button
  • 3 wide voltage input for auxiliary voltage
  • Width 52.5 mm