Instruction Manual
© GE Grid Solutions
12
8.
INSPECTION BEFORE FIRST
ENERGIZING
After putting the CT in vertical
position, it is necessary to wait at
least 48 hours before putting it in
operation.
Verify terminals connections to
assure the correct tightening torque.
Verify if there are no open-circuited
secondary terminals. If so, they must
be short-circuited and earthed.
Verify if one point of each secondary
terminal is connected to ground.
Verify the ground connections of
transformer fixation base.
Verify the correct position of the
primary terminal (transformer with
reconnection primary bars). See set
of drawing.
Verify that the oil level indicator is in the
green strip area.
Whilst all care is taken in the factory
during oil filling, the surface near of
screws and bellows could have a small
quantity of oil. This shall not be
considered as an oil leakage provided
the bellows are positioned within the
green strip area.
It is not necessary to remove oil
samples for analysis. The CT is
hermetically sealed
If required, small quantity of oil can be
taken. Always verify oil level indicator
before take oil samples.
Never complete oil volume without
prior formal authorization of GE.
Important remark
:
During
commissioning,
it
is
recommended to register the values
acquired for each of the performed tests
in order to compare with future
measurements during the CT lifetime.
The measurements taken in the factory
are important as so the measurements
during commissioning of each CT. The
comparison
between
test
results
measured at the field allows following
the evolution of each parameter.
9.
MAINTAINENCE AFTER ENERGIZING
After installation and energizing, the CTs
shall
not
require
any
further
intervention. However, it is suggested
performing visual inspections during the
first weeks of service in order to:
Verify the position of oil level
indicator. CTs in the same circuits
shall have similar oil levels. If the
indicator is significantly below or
above
the
green
level,
in
comparison with other CTs, it is
recommended
checking
the
presence of any of leaking. If
leaking is found, remove the CT
from operation and inform GE;
Verify if there is no oil leakage near
the fixation base and secondary
terminal box;