Figure 24 . Untanking the voltage regulator
Retanking the regulator
Steps for retanking:
1. If the core and coil assembly have been out of oil for
more than 4 hours, the coil must be dried, as follows:
a. Bake the unit at 100˚C (212˚F) for 24 hours.
otee:
N
Units equipped with a phenolic tap-changer
must be baked at a maximum temperature
of 66˚C (150˚F). A unit can be rebaked a
maximum of two times over its life.
b. After baking, check all hardware for tightness.
c. Within four hours after baking, retank the unit and
fill it with fluid.
otee:
N
If baking is not possible or practical, see
for an alternative to baking.
2. Verify that the position indicator shows the present
position of the tap-changer.
otee:
N
If the position indicator is
not
showing the
present position of the tap-changer, proceed as
follows:
a. Remove the indicator cable in the junction
box from the position indicator shaft after
loosening the set screw.
b. Rotate the indicator shaft until the proper
position is reached; then tighten the set
screw.
c. Verify coordination of the position indicator
with the tap-changer in the neutral position
(control neutral light on).
3. Check the gasket seat surfaces on the cover and tank,
and wipe clean. Wipe the gasket and position it on the
tank lip.
4. Loosen the horizontal, side channel bolts to ensure
proper seating of the regulator in the tank and proper
cover seal.
5. Raise the cover assembly and attached components
over the tank. Make certain of proper orientation.
6. Lower the unit, rotating the channels counter-clockwise
into the tank guides.
7. Seat the unit in the tank. Tighten the cover band or
bolts. Torque the cover band to 24.4 – 29.8 Nm
(18 – 22 ft-lbs). Make sure the ends of the cover band
do not touch when fully tightened. Torque the cover
bolts on a square-tanked regulator to 32.5 – 35.6 Nm
(24 – 26 ft-lbs).
otee:
N
On round tanks, tap the cover with a rubber
hammer around the edge to assist in providing a
good seal while tightening the cover band.
8. Check and retighten the horizontal, side-channel bolts
through the hand hole; torque to 68 Nm (50 ft-lbs).
28
VR-32 and EVER-Tap™ Voltage Regulator
InstallatIon, operatIon, and MaIntenance InstructIons
MN225008EN June 2020
