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  • Insulation monitoring device for AC and DC IT systems
  • Application main circuits
  • According to IEC 61557-8
  • Two separately configurable response values
  • Multi-functional LC display

The ISOMETER® of the IR1575 series monitor the insulation resistance of unearthed main circuits (IT systems) AC, 3(N)AC 0…480 V resp. DC 0… 480 V.

The AMP measurement method allows the Isometers to be used in systems with directly connected DC components. Taking the system leakage capacitances into account, the IR1575 automatically adapts itself to the existing system conditions in order to optimise the measuring time. An external supply voltage allows de-energised systems to be monitored too.

Please note that the frequency range of the IR1575 is limited to DC, 30…420 Hz. For use in systems containing variable-speed drives, we recommend to use the iso685 version.


  • Insulation monitoring for unearthed AC, AC/DC systems 0…480 V and DC systems 0…480 V
  • Two separately adjustable response values 2 kΩ…1 MΩ
  • AMP measurement method
  • Automatic adaptation to the system leakage capacitance
  • Injection of the locating current required for selective insulation fault location (only IR1575PG1)
  • LEDs: Alarm 1/Alarm 2
  • Fault memory behaviour, selectable
  • Connection monitoring system/earth
  • Test and reset button
  • Connection external test and reset button
  • Two separate alarm relays with one changeover contact each
  • N/O or N/C operation, selectable
  • Backlit LC display
  • Self monitoring with automatic alarm
  • Plug-in terminals
  • Enclosure for door mounting 96 x 96 mm


  • AC or AC/DC main circuits
  • AC/DC main circuits with directly connected DC components
  • UPS systems, battery systems
  • Heaters with phase control
  • Installations including switch-mode power supplies

ISOMETER® IR1575… Variant(s)

TypeSupply voltage USArt. No.
IR1575-435AC 88…264 V/DC 77…286 V/AC 340…460 VB91064000
IR1575W-435AC 88…264 V/DC 77…286 V/AC 340…460 VB91064000W
IR1575-434AC 16…72 V/DC 10.2…84 VB91064003
IR1575PG1-435AC 88…264 V/DC 77…286 V/AC 340…460 VB91064002
IR1575PG1W-435AC 88…264 V/DC 77…286 V/AC 340…460 VB91064002W
IR1575PG1-434AC 16…72 V/DC 10.2…84 VB91064004

Downloads for ISOMETER® IR1575…

CE Declarations of conformity IR157x 87.7 KB 2022/08/12 06:17:2412.08.2022 06:17:24
Manuals IR1575PG1 2.6 MB DE2021/03/12 07:42:5812.03.2021 07:42:58D00357
Manuals IR1575PG1 2.6 MB EN2021/03/12 07:43:2812.03.2021 07:43:28D00357
Manuals IR1570/IR1575 1.9 MB DE2021/03/12 07:42:5612.03.2021 07:42:56D00309
Manuals IR1570/IR1575 2.2 MB EN2021/03/12 07:43:2512.03.2021 07:43:25D00309
Manuals IR1570/IR1575 1.9 MB ES2020/03/05 09:45:2005.03.2020 09:45:20D00309
Manuals IR1570/IR1575 566.9 KB FR2019/05/13 10:31:5413.05.2019 10:31:54D00309
Datasheets IR1575 327.0 KB DE2019/11/13 15:06:4413.11.2019 15:06:44D00116
Datasheets IR1575 325.9 KB EN2019/11/13 15:06:5013.11.2019 15:06:50D00116
Datasheets IR1575 312.2 KB ES2019/11/13 15:06:5513.11.2019 15:06:55D00116
Datasheets IR1575 421.4 KB ZH2019/05/13 10:31:3313.05.2019 10:31:33D00116
Datasheets IR1575PG1 324.1 KB DE2019/11/13 15:06:4513.11.2019 15:06:45D00357
Datasheets IR1575PG1 322.1 KB EN2019/11/13 15:06:5113.11.2019 15:06:51D00357