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ISOMETER® IR427 with MK7

  • Insulation monitoring device for medical IT systems
  • Load and temperature monitoring for IT system transformers
  • According to IEC 60364-7-710 and IEC 61557-8
  • Two separately configurable response values
  • Multi-functional LC display

The ISOMETER® of the IR427 series is designed to monitor the insulation resistance of AC circuits (medical IT systems). At the same time, the load current and temperature of the IT system transformer can be monitored.



  • Insulation monitoring for medical IT systems
  • Load and temperature monitoring for IT system transformers
  • Adjustable response value for R
  • Adjustable load current response value
  • Integrated voltage monitoring for four alarm and test combinations MK7
  • Temperature monitoring via PTC Thermistor or Bimetal switch (NC)
  • Connection monitoring earth
  • LEDs: Power On, Alarm 1, Alarm 2
  • Internal/external test button
  • Programmable alarm relay: N/O or N/C operation
  • Self monitoring with automatic alarm message
  • Compact two-module enclosure (36 mm)
  • Four-wire interface for four alarm and test combinations MK7

Remote alarm indicator and test combination MK7

  • Easy-to-clean front foil surface
  • Label field
  • Panel frame alpine white
  • Alarm LEDs: Power On, insulation fault overload, overtemperature
  • Test button
  • Mute button
  • Standard flush-mounting enclosure 66 mm


  • Medical IT systems in accordance with IEC 60364-7-710:2002-11, IEC 61557-8 and DIN VDE 0100-710

ISOMETER® IR427 with MK7 Variant(s)

TypeSupply voltage USArt. No.**
IR427-2AC 70…264 V, 42…460 Hz*B72075300
MK7DC 18…28 VB95100201

* Absolute values
**(B7… = push-wire terminal / B9… = screw-type terminal)

Optional Accessories for ISOMETER® IR427 with MK7

TypeArt. No.
STW2 measuring current transformerB942709
ES0107/temperature sensor (PTC)B924186
Mounting frame XM420B990994

Downloads for ISOMETER® IR427 with MK7

CE Declarations of conformity IR42x 94.2 KB 2022/08/12 06:17:2412.08.2022 06:17:24
CE Declarations of conformity MK7 82.7 KB 2022/08/12 06:17:2512.08.2022 06:17:25
Manuals IR427 + MK7 1.8 MB DE2019/05/13 10:31:4113.05.2019 10:31:41D00118
Manuals IR427 + MK7 1.8 MB EN2019/05/13 10:31:4113.05.2019 10:31:41D00118
Manuals IR427 + MK7 1.9 MB ES2019/05/13 10:31:5413.05.2019 10:31:54D00118
Manuals IR427 + MK7 1.1 MB FR2019/05/13 10:31:5413.05.2019 10:31:54D00118
Datasheets IR427 + MK7 578.0 KB EN2019/05/13 10:31:3613.05.2019 10:31:36D00118
Datasheets IR427 + MK7 611.3 KB DE2019/05/13 10:31:3413.05.2019 10:31:34D00118
Datasheets IR427 + MK7 571.4 KB ES2019/05/13 10:31:3713.05.2019 10:31:37D00118
Datasheets IR427 + MK7 679.8 KB ZH2019/05/13 10:31:3313.05.2019 10:31:33D00118