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- Ground Fault Monitoring, Ungrounded

ISOMETER® IR420-D4
- Ground-fault monitoring device for AC IT systems
- Application control circuits
- According to IEC 61557-8
- Two separately configurable response values
- Multi-functional LC display
The ISOMETER® IR420-D4 monitors the insulation resistance of ungrounded AC control circuits (IT systems) 0…300 V. If the systems to be monitored include DC components, such as switched-mode power supplies or solenoid valves, the display and operating characteristics may be affected.
The display and response values apply to pure AC systems. An external supply voltage allows de-energized systems to be monitored too.
- Features
- Applications
- Accessories
- Ordering information
- Downloads
- Insulation monitoring for IT control circuits AC 0…300 V
- Two separately adjustable response values
- Preset function (automatic assignment 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 message
- Multi-functional LC display
- Adjustable response delay
- Two-module enclosure (36 mm)
- RoHS-compliant
- Push-wire terminal (two terminals per connection)
- AC control circuits in the industrial sector, mechanical engineering, power plants, elevators, automation systems etc.
- AC control and auxiliary circuits in accordance with IEC 60204-1 / DIN EN 60204-1 Electrical equipment of machines
- AC auxiliary circuits in accordance with DIN VDE 0100-725 (VDE 0100-725)
- Smaller AC IT systems such as lighting systems, mobile generators
Optional accessories for ISOMETER® IR420-D4
Type | Art. No. |
---|---|
Mounting clip for screw mounting (one piece per device) | B98060008 |
Variants of ISOMETER® IR420-D4
Type | Nominal system voltage* Un | Supply voltage* US | Response value Ran | System leakage capacitance Ce | Art. No.** |
---|---|---|---|---|---|
IR420-D4-1 | AC 0…300 V, 42…460 Hz | DC 9,6…94 V / AC 16…72 V, 42…460 Hz | 1…200 kΩ | < 20 µF | B71016409 B91016409 |
IR420-D4-2 | AC 0…300 V, 42…460 Hz | DC 70…300 V / AC 70…300 V, 42…46 Hz | 1…200 kΩ | < 20 µF | B71016405 B91016405 |
* absolute values
**(B7… = push-wire terminal / B9… = screw-type terminal)
**(B7… = push-wire terminal / B9… = screw-type terminal)
Downloads for ISOMETER® IR420-D4
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