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- Insulation monitoring devices for safety in the IT system

ISOMETER® IRDH375
- Insulation monitoring device for AC and DC IT systems
- Application main circuits with connected frequency converters
- According to IEC 61557-8
- Automatic adaptation to the system leakage capacitance
- Info button to display the device setting
- This device series is in the discontinuation phase. -
Available until 31.12.2023.
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- Insulation monitoring for unearthed AC, AC/DC systems 0…793 V, DC 0…650 V
- Nominal voltage extendable via coupling device
- Two separately adjustable response values 1 kΩ…10 MΩ
- AMPPlus measurement method
- Automatic adaptation to the system leakage capacitance
- Info button to display device settings and the system leakage capacitance
- Continuous self monitoring, with automatic alarm message
- Automatic self test, selectable
- Connection for external kΩ indication
- Test and reset button
- Connection external test and reset button
- Two separate alarm relays with two potential-free changeover contacts
- N/O or N/C operation
- Alarm relay for system fault (N/C operation)
- Backlit LC display
- RS-485 interface
- Plug-in terminals
- AC, DC or AC/DC main circuits
- AC/DC main circuits with directly connected DC components, such as rectifiers, converters, and thyristorcontrolled DC drives
- UPS systems, battery systems
- Heaters with phase control
- Installations including switch-mode power supplies
- IT systems including high leakage capacitances
- Coupled IT systems
Optional accessories for ISOMETER® IRDH375
External kΩ measuring instruments (400 µA)
External kΩ measuring instrument 20 mA
Transparent front plate cover IP65
Coupling devices
Type | SKMP *2) | Art. No. |
---|---|---|
7204-1421 | 120 kΩ | B986763 |
9604-1421 | 120 kΩ | B986764 |
*2) SKMP = scale centre point
External kΩ measuring instrument 20 mA
Type | Art. No. |
---|---|
9620-1421 | B986841 |
Transparent front plate cover IP65
Type | Art. No. |
---|---|
144 x 72 | B98060005 |
Coupling devices
Type | Nominal system voltage Un | Art. No. |
---|---|---|
AGH150W-4 | DC 0…1760 V | B98018006 |
AGH204S-4 | AC 0…1300 V / 0…1650 V | B914013 |
AGH520S | AC 0…7200 V | B913033 |
Variants of ISOMETER® IRDH375
Type | Nominal voltage Un | Supply voltage US | Art. No. |
---|---|---|---|
IRDH375-435 | AC 0…793 V / DC 0…650 V* | AC 88…264 V / DC 77…286 V* | B91065000 |
IRDH375-427 | AC 0…793 V / DC 0…650 V* | DC 19.2…72 V* | B91065002 |
IRDH375B-435 | AC 0…793 V / DC 0…650 V* | AC 88…264 V / DC 77…286 V* | B91065004 |
IRDH375B-427 | AC 0…793 V / DC 0…650 V* | DC 19.2…72 V* | B91065006 |
* absolute values
Device “Option-W” with increased shock and vibration resistance: Indicated by the letter “W” at the end of the order number
Device “Option-W” with increased shock and vibration resistance: Indicated by the letter “W” at the end of the order number
Downloads for ISOMETER® IRDH375
Category | Product | Language | Size | Download |
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