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Les langues disponibles
ICAR PQS
Problems
The controller switches in
all the capacitor banks
without increasing the
power factor on the
display
The controller switches
the capacitor banks in and
out continually, without
finding a balance
8
MAINTENANCE
8.1
Routine maintenance
Periodic checks should be carried out on the following items, by filling the sheet of the maintenance logbook attached
at the end of this manual:
- Current drawn by the single steps, in order to keep the operating conditions of the system always under control.
- Electronic units (reactive power controller) so as to check their efficiency.
- Fuses of the control circuits.
- Fuses of the capacitor banks (provided with disconnect switch).
- Check the operating temperature condition, therefore efficiency of the exhaust electric fan. It is essential to carry
out the 3 monthly maintenance of the suction filters in order to ensure correct recirculation of the air inside the
system and to avoid build up of dust inside. In fact, dust, together with humidity, could become a hazardous factor
of surface conductivity on the insulating materials. The maintenance operation and cleaning should be performed
by qualified personnel.
- Check efficiency of the contactors by periodically inspecting the terminals for tight connection.
- Check for presence of capacitors with the overpressure device tripped (this can easily be recognized by expansion
in the top zone of the casing). Restore them immediately by installing new capacitors (it is necessary to replace
such units in order not to impair the efficiency of the entire system).
- We recommend keeping a minimum quantity of spare components always on hand in order to act quickly on the
system. Likewise this operation should be carried out by qualified personnel.
Particularly important is the testing of the capacitors on units of the FD, and FH series, where it is essential to check
whether the filter tuning frequency has not altered over a period of time; although the components used are highly
reliable, it could be possible for a capacitor nearing the end of its working life, to cause tripping of relative overpressure
device.
The consequent drop in capacity could cause a variation in the tuning frequency of the filter thus producing hazardous
overloads.
In order to ensure long-term protection against such possible phenomena it is advisable to check the amount of current
drawn by each step during the initial installation phase, and after the first month of operation, then four times a year;
obvious differences between subsequent measurements or any unbalance between the three phases are symptoms
of a no longer reliable operation and this could require special maintenance.
8.2
Special maintenance
Carry out accurate maintenance work each time the unit requires it because it is subject to unusual and unexpected
phenomena.
A more accurate maintenance schedule should be drawn up taking into account the particular operating conditions.
For example, a highly polluted environment (dust-laden or salty) could require more frequent cleaning of the filters.
8.3
Replacement of components
In power factor correction systems, as in all electric-electronic equipment, it is not sufficient to replace the individual
components; rather it is necessary to understand the causes determining the inefficiency.
A. Replacement of fuses.
Before replacing a fuse on the power circuit or the control circuits, eliminate the cause determining the event. Replace
them with a type equivalent to the original ones.
B. Replacement of the contactors.
Probable causes
The controller is faulty.
Current transformer installed at
incorrect point of the system, only
upstream of the load, but downstream
of the power factor correction system.
The current transformer is enabled on
the incorrect phase
Faulty setting of the controller
Remedies
Replace it with one equal to the original type
Correctly position the current transformer
upstream of all the loads and power factor
correction.
Position the current transformer on phase
L1 (R) referred to our cabinet.
Check current parameters and set them
parameters.
correctly.
MAT189 revJ jan18
12
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