Function
18
isoPV1685-1685PFR_D00007_02_M_XXEN/10.2016
Parameterisation of insulation fault location
By means of the BMS gateway, e.g. the COM460IP or terminal program, different modes can be
selected via the BMS bus:
•
off:
Switch off insulation fault location
•
auto (automatic): (Factory setting)
Insulation fault location and pause, alternately 5 minutes each. During each pause, the device
automatically switches to insulation fault measurement.
•
1 cycle:
The locating current required for insulation fault location is supplied for 1 cycle (about 5 min-
utes) to the device.
•
on (permanent):
The locating current required for insulation fault location is permanently supplied to the device.
In addition, the value of the locating current required for insulation fault location has to be set to
1…50 mA.
3.3.3
Residual current monitoring (isoPV1685PFR)
For the detection of insulation faults on the AC side, residual current monitoring was integrated into
the isoPV1685PFR. An external measuring current transformer with one measuring and test winding
is required for this purpose.
For current transformer monitoring an appropriate signal is delivered via the test winding that is
evaluated by the measurement winding.
3.3.4
Self test
3.3.4.1
Self test after connection to the supply voltage
Once connected to the supply voltage, all internal measurement functions, the components of the
process control such as data and parameter memory as well as the connections to earth are checked.
Once the self test is finished, after approx. 5 s the normal measurement mode begins.
If a device or connection error is detected, the corresponding alarm will be signalled via the BMS bus
as well as via the alarm relay K3 (31-32-34). This relay is continuously operating in N/C operation,
i.e. it de-energises even in case of a complete device failure.
During this self test, when the device is being started, the alarm relays K1 and K2 are not switched.
3.3.4.2
Automatic self test
All supply voltages are continuously monitored. The following tests are continuously carried out in
the background:
- Connection E-KE
- System polarity
- Residual current transformer (connection, short-circuit, isoPV1685PFR only)
- Temperature measurement
- Pulse generator
