Function; Common Characteristics (Irdh275 And Irdh275B); Additional Characteristics Irdh275B - Bender ISOMETER IRDH275 Handbuch

3. Function

3.1 Common characteristics (IRDH275 and IRDH275B)

• ISOMETER® for IT AC systems with galvanically connected rectifiers and
for IT DC systems (IT = unearthed systems)
• The operating range of the nominal voltage U
coupling devices.
• Automatic adaptation to the existing system leakage capacitance
•
• Two separately adjustable ranges of the response value1 kΩ...10 MΩ
(Alarm 1, Alarm 2)
• Two-line LC display
• Connection monitoring (monitoring of the measuring leads)
• Automatic device self test
• Option "W":
This option provides: improved shock and vibration resistance for use
in ships, on rolling stock and in seismic environment.

3.2 Additional characteristics IRDH275B

• Memory with real-time clock to store all alarm messages with date and
time stamp.
• BMS interface (BMS protocol) for data exchange with other Bender
devices (RS485 electrically isolated).
• Internal disconnection of the ISOMETER from the IT system to be moni-
tored (using a control signal; terminals F1/F2) , e.g. if several
ISOMETERs® are interconnected.
• Current output 0(4)...20mA (galvanically separated) in relation to the
measured insulation value.
• Remote setting of certain parameters via the Internet
(option; COM465 additionally required)
IRDH275_D00122_03_M_XXEN/05.2017
measuring principle (European Patent: EP 0 654 673 B1)
can be extended via
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