AUTOTRANS
LINEATOR™
2
ATL-M001-A2
3.0 Maintenance
WARNING
Internal maintenance must be
performed with a transformer de-
energized, isolated and with the
terminals grounded.
3.1 Periodic Inspection and Maintenance
The
AUTOTRANS
L
INEATOR
™
has no moving or
active parts and therefore requires only minimal
periodic maintenance when installed in a clean
and well ventilated environment. This should
include:
3.1.1 Visual inspection for evidence of loose
connections, dirt, moisture, rusting,
corrosion, and deterioration of the
insulation, varnish or paint.
Observations should be made for signs
of overheating and overvoltage creeping.
Corrective measures should be taken as
necessary
.
3.1.2 For early detection of any developing
hotspots, an infrared scan can be
performed
while
the
AUTOTRANS
L
INEATOR
™
is operating under
its heaviest load condition.
3.1.3
Measuring the current in each of the 3
phases of the capacitor circuit can be a
quick and easy method of determining
the condition of the capacitors. The
capacitors can be assumed to be in good
operating condition when all 3 phases
carry approximately the same amount of
load current. Measurements should be
taken at the input to the capacitor fuse
block and can be done at any loading
condition. If the phase currents are found
to be substantially different, the unit
should be taken offline and serviced by a
qualified technician. This test should be
conducted annually or whenever the unit
seems to be operating in an abnormal
manner.
3.2 Cleaning
Excessive accumulations of dirt on the transformer
windings or insulators and capacitor terminals
should be removed to permit free circulation of air
and to guard against the possibility of insulation
breakdown. Particular attention should be given to
cleaning the top and bottom ends of the winding
assemblies and to cleaning out ventilating ducts.
Windings should be lightly cleaned by the use of a
vacuum cleaner. If necessary a blower or
compressed air may be used but pressure should
not exceed 25 psi. Lead supports, tap changers
and terminal boards, bushings, and other major
insulating surfaces should be brushed or wiped
with a dry cloth. The use of liquid cleaners is not
recommended due to deteriorating effects on most
insulating materials.
3.3 Drying of Core and Coil Assembly
CAUTION
Constant attention during the
drying process is recommended.
When it is necessary to dry a
AUTOTRANS
L
INEATOR
™
transformer
before
installation or after an extended shutdown under
relatively high humidity conditions, internal and/or
external heating methods can be used. (See
ANSI/IEEE C57.94-1982 for a description of these
methods).
It is important that most of the heated air pass
through the winding ducts and not around the
sides. Good ventilation is essential in order that
condensation not take place in the reactor itself or
inside the case. A sufficient quantity of air should
be used to assure approximately equal inlet and
outlet temperatures.
Air temperature should not exceed 70°C.
