9.12 Current Transformers (C.T.’s)
WARNING:
CURRENT TRANSFORMERS
SECONDARIES MUST BE CONNECTED TO
A LOAD OR SHORT CIRCUITED TO AVOID
DAMAGING VOLTAGES AT THE TERMINALS.
FAILURE TO MAKE THESE CONNECTIONS
COULD RESUILT IN SEVERE PSERONAL INJURY,
DEATH OR PROPERTY DAMAGE.
For safety, shorting pins are installed in the terminal block
for current transformers. Only remove the shorting pins
after making final connections. Refer to wiring diagram for
specific details.
10.0 MAINTENANCE
A periodic visual inspection of the transformer is
recommended. At such times, the general condition of the
following should be noted:
A. High voltage bushings.
B. Low voltage bushings.
C. Arresters (if provided).
D. Enclosure integrity (hinges, locking provisions,
corrosion, etc.)
E. Evidence of oil leakage.
F. Ground connections.
G. Accessories.
H. Safety labels.
I.
Transformer tilt.
WARNING:
WHEN BROKEN PARTS, LEAKING
OIL OR OTHER POTENTIALLY HAZARDOUS
CONDITIONS ARE OBSERVED, REMOVE THE
TRANSFORMER FROM SERVICE UNTIL REPAIRS
CAN BE COMPLETED. FAILURE TO DO SO CAN
CAUSE SEVERE INJURY, DEATH OR PROPERTY
DAMAGE.
Where tanks show evidence of rusting or deterioration
of the finish, they may be cleaned and then retouched
with paint available for that purpose. When bare metal is
exposed, a primer should initially be applied, then touch up
paint applied.
A periodic check of the load should be made to ensure
that the transformer is not being subjected to excessive
overload. Planned overloading should be in accordance
with the ANSI Loading Guide (C57.91).
When adding oil to the transformer, the owner should take
the necessary precautions so that PCB contamination is
not introduced.
WARNING:
OIL SAMPLES SHOULD BE TAKEN
FROM THE TRANSFORMER ONLY
AFTER
DE-
ENERGIZING AND MANUALLY VENTING THE
TRANSFORMER. FAILURE TO DO SO CAN
CAUSE SEVERE INJURY, DEATH OR PROPERTY
DAMAGE.
Whenever replacement parts or information regarding
existing
transformers
are
required,
COMPLETE
NAMEPLATE data including KVA rating, STYLE NUMBER,
SERIAL NUMBER , and a DESCRIPTION of the part
should be given to ABB,Inc.
11.0 REPAIR
WARNING:
BEFORE ATTEMPTING REPAIRS,
DE-ENERGIZE AND VENT THE TRANSFORMER.
FAILURE TO DO SO CAN CAUSE SEVERE INJURY,
DEATH, OR PROPERTY DAMAGE.
It is the responsibility of the owner to inspect, maintain and
keep the transformer in good repair.
Report all failures during the warranty period to your ABB
Sales Office. All warranty repairs must be made by ABB or
an approved service facility.
To assure proper operation, use only ABB approved
replacement parts.
It is recommended that the owner limit repairs to replacing
broken parts unless the owner has well - trained repair
personnel.
Some internal parts can be replaced without completely
draining the tank. In such cases, only the fluid necessary
to expose the part should be drained. There may also be
occasions when complete draining of the transformer tank
will be necessary.
The core and coil assembly can be repaired or replaced
by ABB personnel at either the factory or at an authorized
repair facility. Contact ABB, Inc. for details.
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