Bender ISOMETER iso1685DP-425, Manual

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Function
15 isoxx1685Dx-x25_D00272_07_M_XXEN/09.2022
3.3.2 Insulation fault location
For insulation fault location, a suitable locating current is superimposed onto the faulty IT sys-
tem with which insulation fault locators of the EDS... series can locate insulation faults. The
ISOMETER® features an internal locating current injector with
I
L
DC 50 mA.
Pulse sequence of the internal locating current injector for insulation fault location
If the "Auto EDS function" is enabled, the ISOMETER® starts the insulation fault location after
the value has fallen below the response values
R
an1
and R
an2
. When starting the insulation
fault location, the "PGH ON" LED signals the locating current pulse.
During the insulation fault location process, the measurement of the insulation resistance is
deactivated and the coupling is disconnected from the mains. If during the insulation fault lo-
cation the locating current falls below the value measurable by the EDS, the insulation fault
location is terminated by the ISOMETER®.
3.3.3 Assignment of the alarm relays K1, K2, K3
K1 switches when the value falls below the alarm response value R
an1
(insulation resistance).
K2 switches when the value falls below the alarm response value R
an2
(insulation resistance).
K3 switches in the event of a device error or a connection fault.
3.3.4 Deactivating the device
When the device is deactivated, the coupling unit of the device is galvanically isolated from
the system being monitored.
The device does not measure the insulation resistance, the message "Device inactive" appears
on the display. The IT system is NOT being monitored!
The device uncouples itself from the system to be monitored through an internal system iso-
lating switch.
CAUTION
Malfunctions due to excessive locating current on sensitive system
parts!
The locating current flowing between the IT system and earth can
cause controller faults in sensitive parts of the system, such as the PLC or relay.
Ensure that the level of the locating current is compatible with the system to
be monitored.
2 s 4 s 2 s 4 s
I
L
t