Oil Level Indicator; Inspection Before First Energizing - GE OTEF-72 Instruction Manual

Instruction Manual
not damage the bellows.
•Remove the bellows blocking system (kit of
synthetic cushion).
•Confirm by visual inspection that the
bellows are in good condition.
Geometry:
- The bellows cover in at horizontal: it is not
tilted by a possible deformation in the
bellows.
- The bellows is neither distorted nor
asymmetric: the convolutions are equally
distributed around
circumference.
Surface:
- There is no damage or deformation like
those caused by blows.
•Confirmed that the bellows is in good
condition, put the top cover in the original
position.
•Tight the four M6 screws with torque of
2kgf.m.
In case bellows
deformation or blow the VT should not be
put into service unless there is a formal
release from GE. In case of doubts, to contact
the technical assistance support of GE for
further information.

7. OIL LEVEL INDICATOR

The position of the oil level indicator can be
verified through the window of the top
cover. The plate of the indicator is divided in
three areas. Central green area shows the
normal operation condition and higher and
lower areas are shown with a red strip. In
normal conditions, the indicator shows the
central green area.
In case of oil level indicator is in either of the
red areas, the VT shall be taken off from
© GE Grid Solutions
the bellows
show any type
operation and GE informed immediately.
Example of oil level indicator

8. INSPECTION BEFORE FIRST ENERGIZING

•Confirm terminals connections to assure the
correct tightening torque.
•Confirm that there are no short-circuited
secondary terminals. If so they must be
opened and earthed.
•Confirm
transformer tank.
•Confirm that the oil level indicator is in the
central green area.
of
The VT are routine tested in the factory and
do not require repeated electric test. Look
for Project routine test reports for more
details.
Whilst al care is taken in the factory during
oil filling, the surface near of screws and
bellows could have a small quantity of oil.
This should not be considered as an oil
leakage provided that the bellows are
positioned within the green strip area.
It is not necessary to remove oil samples for
analysis. The VT is hermetically sealed.
If required, small quantity of oil can be taken.
Always verify oil level indicator before take
oil samples.
the ground connections of