Hitachi APCQ - Page 40

APCQ CAPACITOR BANKS
STATUS
Approved
SECURITY LEVEL
Public
DOCUMENT ID
9AKK107680A4136
RE V.
E
LANG.
en
PAGE
40/47
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.
APCQ
- Maintenance check list
Iss
ued by:
Date:
Regular maintenance procedure
OK/NOK
− Check ambient temperature and equipment ventilation (should be within specification).
− Isolate the APCQ capacitor bank from power supplies.
− Open the front door panel.
− Clear air inlet and outlet.
− Clean all parts from dust and dirt.
− Check fuses (shouldn’t be brown).
− Switch on each power step manually with RVC/RVT Controller.
− Check contactors and their good operation – replace them if necessary.
− Check operation of RVC/RVT Controller.
−
Measure capacitors currents (in the three phases) for every power step and record the
measurements1.
QCap
I Phase A
I Phase B
I Phase C
I Nominal
OK/NOK
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
Fan replacement
OK/NOK
Fans have to be replaced every 5 years (40 000 hours)
1
current measurements should be compared to previous measurements. If current is 10% lower than first
measurement, capacitors have to be replaced.
Nominal current is normally given by:


=




√
3
Where:


= current in one phase - 

= Reactive power (kvar) on the power step -
√
3 = square root of three -


= RMS value of phase to phase voltage