Atlas Copco QAS 60 Pd, Instruction Manual

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S10 ..... Output voltage selection switch
Allows to select a 3 phase high output
voltage or a 1 phase / 3 phase low output
voltage. Selector switch S10 is located on
the alternator.
9.3.11 Earth leakage relay
The Earth relay option provides a detector that will
trip the main circuit breaker Q1 when an earth fault
current is detected.
Q1 ....... Main circuit breaker
N13 .....Earth leak detector
Detects and indicates an earth fault current
and activates the main circuit breaker Q1.
The detection level can be set at 30 mA fixed
with instantaneous trip but can also be
adjusted between 0.1 A and 1 A with time
delayed (0 - 0.5 sec) trip. N13 has to be reset
manually after eliminating the problem
(reset button marked R). It can be overridden
by means of the earth leak switch (S13,
labelled I

N) but has to be tested monthly
by pushing test button T13.
S13......Lock-out switch for earth fault
protection (N13)
This switch is located inside the cubicle and
is labelled I

N.
Position O: No de-energising of the main
circuit breaker Q1 when an earth fault
occurs.
Position 1: De-energising of the main circuit
breaker Q1 when an earth fault occurs.
Changing the output voltage is only
allowed when the unit has stopped.
After changing the output voltage by
means of the selection switch S10,
adjust the output voltage by means of
potentiometer R12 to the required
value.
!
X1
Q1
N13
N14
S13