ABB UCG Series, Installation And Commissioning Manual

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1ZSC000562-AAZ en | Installation and commissioning guide UCL/VUCL 51
9.2.6 Mounting of horizontal drive shafts for three units
The following applies to the fitting of drive shafts and their
protective tubes when the on-load tap-changer consists of
three insulated units UCL.T/VUCL.T or UCLYD/VUCLYD. The
on-load tap-changer unit, which is placed closest to the drive
mechanism, is called unit
-1 , the second unit -2 and the last
unit
-3
; see Fig. 35.
1. Mount the drive shaft on the on-load tap-changer unit -1
according to Section 9.2.5, steps 1–5. Remove the set
screws according to Fig. 43.
2. Mount the drive shaft between unit -1 and unit -2
according to Section 9.2.5, steps 1-6. Remove the set
screws according to Fig. 43.
3. Mount the drive shaft between unit -2 and unit -3
according to Section 9.2.5, steps 2-7.
The shaft here is SA34, the protective tube closest to
unit -2 is SA35 and the other protective tube is SA36.
Do not remove the locking device before one end of
the shaft of the bevel gear is connected to the drive
shaft.
In cases where a support bearing is used, follow the
appropriate parts of Section 9.2.5, steps 2-5.
9.2.7 Before operation
1. Check again that the on-load tap-changer and the motor-
drive mechanism are at the same operating position; see
Section 5.1.
2. Remove the locking device for the motor-drive mechanism;
see Fig. 44.
WARNING
Assembly with the on-load tap-changer and the
motor-drive mechanism at different operating
positions may cause transformer failure.
The door of the motor-drive mechanism can be
locked with a padlock (not included
in the delivery).
Do not remove the locking device before one end of
the shaft of the bevel gear is connected to the drive
shaft.
9.3 Supervisory equipment
Accessories and safety devices are described in
Accessories
and protection devices for on-load tap-changers,
1ZSC000562-AAD
.
9.4 Accessories
Refit all other accessories, if any, that have been removed for
transport. Follow the appropriate parts of Section 5.4.
9.5 Oil filling
Follow the appropriate parts of Chapter 6.
9.6 Electrical connection and testing
Carry out all wiring work and appropriate tests according to
Chapter 7. Remove the drying agent inside the cabinet of the
motor-drive mechanism.
9.6.1 Motor protection
The function of the protective motor switch is checked. For
three-phase AC motors, one of the phase fuses is removed
and the function time of the protective motor switch is
checked by a RAISE or LOWER operation. The protective
motor switch should release within 60 seconds at a current
setting equal to the rated current of the motor at the actual
voltage.
WARNING
The motor power voltage is dangerous.
CAUTION
If the protective motor switch has not released within
60 seconds, disconnect the power and check the
settings against the rating plate of the motor. Adjust
if necessary and check again when the motor has
cooled down.
Protective motor switches for DC motors and for single-phase
AC motors are not tested.