Bender ISOMETER isoHV525, Manual

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Function
15 isoHV525_D00297_04_M_XXEN/05.2018
3.2 isoHV525-S4-4
3.2.1 Device features
 
Monitoring the insulation resistance R
F
for unearthed AC/DC systems
 
Measurement of the nominal system voltage U
n
(True RMS) with undervoltage
and overvoltage detection
 
Measurement of residual voltages to earth (L1+/PE and L2-/PE)
 
Automatic adaptation to the system leakage capacitance C
e
up to 150 μF
 
Two separate response values for Alarm 1 and Alarm 2
 
Alarm are signalled via alarm relays ("K1", "K2")
 
Selectable N/C or N/O relay operation
 
Selectable start-up delay, response delay and delay on release
 
Fault memory can be activated.
 
RS-48 5 (galvanically isolated) with the following protocols:
– BMS interface (Bender measuring device interface) for data exchange with
other Bender components
– Modbus RTU
– IsoData (for continuous data output)
3.2.2 Function description
The ISOMETER® measures the insulation resistance R
F
and the system leakage capaci-
tance C
e
between the system to be monitored (L1/+, L2/-) and earth (PE). The RMS value
of the nominal system voltage U
n
between L1/+ and L2/-, as well as the residual volta-
ges U
L1e
(between L1/+ and earth) and U
L2e
(between L2/- and earth) are also measu-
red. From a minimum value of the nominal system voltage, the ISOMETER® determines
the faulty conductor L1/+ or L2/-, which shows the distribution of the insulation resis-
tance between conductors L1/+ and L2/-.
The value range of the faulty conductor is
±100 %:
Display Meaning
-100 % One-sided fault on conductor L2/-
0 % Symmetrical fault
+100 % One-sided fault on conductor L1/+