iTD uni-cart Gebrauchsanweisung Seite 42

ELECTRICAL SAFETY
the temperature of the transformer is evaluated by a built-in thermal switch which responds
when triggered. The evaluation procedure is processor controlled.
3.6.3 Application requirements
Turn the main power switch of the isolating transformer to "ON". Within 5 s the self-test of the ELG
is automatically activated. After the self-test of the ELG is concluded, the green LED (Power on
control) glows permanently. During operation this test is repeated (automatically) in a time cycle of
8 hours. This self-test may also be activated manually through the test-button.
The control procedure for the manual self-test is as follows:
• An insulation error is simulated, the yellow LED (signals exceeding dielectric resistance)
glows, a warn signal (2.4 kHz) is activated. Both signals stop after approx. 5 s.
• Following this, a temperature error is simulated. The yellow LED (signals exceeding
temperature) glows, a warn signal (2.4 kHz pulse tone) is activated. Both signals stop after
approx. 5 s.
An error situation is recognized as follows:
• In case of an insulation error, the yellow LED (signals exceeding dielectric resistance)
glows permanently, the warn signal with 2.4 kHz is activated permanently. The warn signal
can be deactivated through the reset-button for fault release. The LED glows until the error
is eliminated.
• If the earth-leakage-guard is turned "OFF" in the meantime and the error is not eliminated,
when turning the ELG back "ON" the above described procedure begins anew.
With the occurrence of an isolation error the acoustic and optical alarm stays activated
(even if the isolation error is corrected on its own) until deactivated through the fault release:
First activation of the fault release: acoustic alarm is deactivated
Second activation of the fault release: optical alarm is deactivated
• In case of a temperature error, the yellow LED (signals exceeding temperature) glows
permanently and the warn signal with 2.4 kHz is activated intermittent. The warn signal can be
deactivated through the reset-button for fault release. The LED glows until the error is
eliminated. If the earth-leakage-guard is turned "OFF" in the meantime and the error is not
eliminated, when turning the earth-leakage guard back ON the above described procedure
begins anew.
• Should an insulation error and a temperature error occur simultaneously, the dielectric
resistance fault has priority (acoustic).
Self test for the Earth-Leakage Guard
In addition to the manual self-test, during operation the earth-leakage-guard repeats the self-test
in a time cycle of 8 hours and each time the unit is turned "ON".
From outside, you will not notice the self-test, the time period for this process is approx. 5 seconds.
In case of fault, the green LED (power on control) blinks in a frequency of 0.5 Hz and with the same
frequency an acoustic alarm is activated. The fault signal can not be deactivated through the reset-
button.
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