13
isoMIL425_D00203_03_M_XXEN/03.2019
3. Function
3.1
Device features
Monitoring of the insulation resistance
R
F
(R mode) or the insulation
impedance
Z
F
(Z mode) of unearthed 3(N)AC, AC and DC systems
(IT systems) with galvanically connected rectifiers or inverters
Insulation impedance
Z
F
(Z mode) for 50 Hz or 60 Hz
Measurement of the nominal system voltage
U
n
(True RMS) with und-
ervoltage and overvoltage detection
Measurement of residual voltages system to earth (L+/PE and L-/PE)
Automatic adaptation to the system leakage capacitance
C
e
up to
300 μF in R mode and 1μF in Z mode
Automatic device self test with connection monitoring
Selectable start-up delay, response delay and delay on release
Two separately adjustable response ranges of 1…990 kΩ (alarm 1,
alarm 2)
Alarm signalling via LEDs ("AL1", "AL2"), a display and alarm relays ("K1",
"K2")
N/C operation or N/O operation can be selected for the relays
Measured value indication via multi-functional LCD
Fault memory can be activated
RS-485 (galvanically isolated) including the following protocols:
– BMS interface (Bender measuring device interface) for data
exchange with other Bender components
– Modbus RTU
– IsoData (for continuous data output)
Password protection to prevent unauthorised parameter changes
