The ISOMETER®s of the IR425 series monitor the insulation resistance of unearthed AC/DC control circuits (IT systems) 0…300 V. DC components existing in AC/DC systems do not influence the operating characteristics. An external supply voltage allows de-energised systems to be monitored too.

• AC/DC control circuits in the industrial sector, mechanical engineering, power plants,
elevators, automation systems etc.
• AC/DC control and auxiliary circuits in accordance with DIN EN 60204-1
“Electrical equipment of machines”, IEC 60204-1, EN 60204-1
• AC/DC auxiliary circuits in accordance with DIN VDE 0100-725 (VDE 0100-725)
• Smaller AC/DC IT systems such as lighting systems

• Insulation monitoring for AC/DC control
circuits 0…300 V
• Two separately adjustable response values
• Preset function
(automatic setting of basic parameters)
• Connection monitoring system/earth
• LEDs: Power On, Alarm 1, Alarm 2
• Internal/external test/reset button
• Two separate alarm relays
(one changeover contact each)
• N/O or N/C operation, selectable
• Fault memory behaviour, selectable
• Self monitoring with automatic alarm
• Multi-functional LC display
• Adjustable response delay
• Two-module enclosure (36 mm)
• Push-wire terminal
(two terminals per connection)