Bender EDS460, Operating Manual

Page: 51 / 88

Operation
51 TGH1394en/05.2007
4.Release delay T(off)
This function is only effective when the fault memory is deactivated
(see "1.Fault memory" on page 48).
If the status that triggered the alarm no longer applies, the EDS... will
terminate its alarm once the release delay has expired.
Configurable values: 0s, 6s, 12s, 18s, 24s
0s
The alarm is terminated when the EDS... has not recog-
nized an insulation fault for the duration of a test current
pulse.
6s The alarm is terminated when the EDS... has not recog-
nized an insulation fault for the duration of two test cur-
rent pulses.
12s The alarm is terminated when the EDS... has not recog-
nized an insulation fault for the duration of three test
current pulses.
5.CT monitoring
Enable or disable monitoring of the measuring current transformers.
ON Measuring current transformers are monitored.
Open circuit, short circuit or missing measuring current
transformers generate an alarm message. The "ALARM 1"
LED lights up.
OFF Measuring current transformers are not monitored.
In the case of DC systems, a release delay of at least 6 sec-
onds must be set in order for a pending fault to be perma-
nently signalled.
IRDH575 / PGH... sends alternate positive and negative
test current pulses. However, in a DC system, test current
pulses must either be all positive or all negative. As only
every second test current pulse counts, the system must
wait for a further test current pulse to be sent (6 seconds)
before it can be certain that this measuring channel is
free from insulation faults.