Innovative technologies for safe handling of electrical power to achieve high availability

We offer you first-class quality and safety combined with global service and every support in resolving your monitoring problems.

  • Electrical safety for unearthed power supplies (IT systems)
  • Insulation monitoring equipment, insulation fault location systems
  • Power supplies for medical applications
  • Measuring and monitoring relays
  • Electrical safety for earthed power supplies (TN systems)
  • Using renewable energies efficiently: wind power, photovoltaics
  • Test systems for electrical equipment and medical technology
ISOMETER® iso1685DP-425/isoHV1685D-425/isoLR1685DP-325

ISOMETER® iso1685DP/isoHV1685D/isoLR1685DP

  • Insulation monitoring device for AC 1000 V and DC 1500 V IT systems
  • Application main circuits with connected frequency converters
  • Separately adjustable response values 200 Ω…1 MΩ
  • Display and control function for EDS insulation fault location systems
  • Can be extended to operate as an insulation fault location system

The ISOMETER® isoxx1685Dx-x25 is used for insulation monitoring of extensive IT systems. The specially developed measurement method monitors the insulation resistance also in installations where extremely high system leakage capacitances against earth exist due to interference suppression methods. Adaptation to system-related high leakage capacitances also occurs automatically.

The ISOMETER® iso1685Dxx generates locating current pulses required for insulation fault location. That allows the localisation of the insulation fault using permanently installed or mobile insulation fault locators.


  • ISOMETER® for IT AC systems with galvanically connected rectifiers or inverters and for IT DC systems (IT = unearthed systems)
  • Automatic adaptation to the existing system leakage capacitance
  • Combination of AMPPlus and other profile-specific measurement methods
  • Two separately adjustable response value ranges of 1 kΩ…10 MΩ for Alarm 1 and Alarm 2
  • High-resolution graphical LC display
  • Connection monitoring (monitoring of the measuring lines)
  • Automatic device self test
  • Graphical representation of the insulation resistance over time (isoGraph)
  • History memory with real-time clock (buffer for three days) for storing 1023 alarm messages with date and time
  • Freely programmable digital inputs and outputs
  • Remote setting via the Internet or Intranet (COMTRAXX® gateway)
  • Worldwide remote diagnosis via the Internet (made available by Bender Service only)
  • RS-485 interface for data exchange to other Bender devices


  • measuring insulation faults 200 Ω…1 MΩ


  • measuring insulation faults 20 Ω…100 kΩ


  • measuring insulation faults 200Ω …1MΩ at mains voltages AC 2000 V, DC 3000 V

iso1685DP-425 and isoLR1685DP-325

  • Locating current injection for selective insulation fault location
  • Indication of the insulation faults selectively located by the EDS system
  • Parameter setting of EDS systems
  • Customer-specific texts for each measuring channel


  • Extensive systems up to AC 2000 V/DC 3000 V which are designed as IT systems
  • Low-resistance applications from 20 Ω

Downloads for ISOMETER® iso1685DP/isoHV1685D/isoLR1685DP

Handbücher iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 1.9 MB DE10.06.2020 13:33:28D00272
Handbücher iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 1.8 MB EN13.05.2020 05:26:02D00272
Datenblätter iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 760.2 KB DE19.05.2020 13:23:28D00272
Datenblätter iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 715.5 KB EN19.05.2020 13:23:39D00272
Software iso1685 Set V2.1 48.1 KB DE13.05.2019 10:31:59
Software iso1685 Set V2.1 48.1 KB EN13.05.2019 10:31:59
Kurzanleitungen iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 990.5 KB DE14.05.2019 06:57:06D00272
Kurzanleitungen iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 990.5 KB EN14.05.2019 06:57:06D00272
Kurzanleitungen iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 1.2 MB FR12.07.2019 09:59:50D00272
Kurzanleitungen iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 1.2 MB ES12.07.2019 09:59:50D00272
Datenblätter iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 718.3 KB FR19.05.2020 12:34:15D00272
Datenblätter iso1685DP-425/isoHV1685D-425/isoLR1685DP-325 576.7 KB ES19.05.2020 13:18:42D00272
Handbücher isoxx1685Dx Gerätefamilie - Modbus-Einstellung 311.4 KB DE10.06.2020 10:02:21D00272
Handbücher isoxx1685Dx Device family - Modbus settings 139.6 KB EN07.11.2018 15:26:27D00272
Produktbroschüren Mining Brochure 11.7 MB ES22.05.2020 14:37:31
Produktübersichten Gamme de produits - IMD: le chaffeur par induction 880.8 KB FR13.01.2021 15:57:40
Produktübersichten Product overview - IMD: Inductive heating 844.0 KB EN13.01.2021 15:58:12
Produktübersichten Produktübersicht - IMD: Induktives Erwärmen 880.9 KB DE13.01.2021 15:58:42

Optional accessories for ISOMETER® iso1685DP/isoHV1685D/isoLR1685DP

ISOMETER® iso1685DP/isoHV1685D/isoLR1685DP Variants

TypeResponse value rangeNominal system voltageSupply voltage*Art. No.
isoLR1685DP-32520 Ω…100 kΩAC 0…690 V / DC 0…690 VDC 18…30 VB91065803
isoHV1685D-425200 Ω…1 MΩAC 0…2000 V / DC 0…3000 VDC 18…30 VB91065805
iso1685DP-425200 Ω…1 MΩAC 0…1000 V / DC 0…1500 VDC 18…30 VB91065802

* Absolute values