22
1ZSE 5492-129 en, Rev. 6
3. Repairs and adjustments
3.1 Replacement of gear box on the on-load tap-changer or replacement of o-rings for the gear
box
3.1.1 General
This instruction guides you on how to replace the gear box on the top section of the UCG,
UCL and UCC, UCD on-load tap-changers.
If the gasket only is to be replaced, follow appropriate parts of the instructions.
WARNING
The gearbox contains moving gears. Be cautious!
CAUTION
When making this repair it is important that neither the on-load tap-changer nor the motor-
drive mechanism is operated with the shafts disconnected.
3.1.2 Tools required
■ Normal set of handtools
■ Socket wrench with extension socket for 8 mm Allen screw
■ Sliding caliper
■ Graduated limb
3.1.3 Material and spare parts required
■ Gear box
■ O-ring (84.1 x 5.7), for UCL
O-ring (92.5 x 5.7), for UCG, UCC, UCD
■ Loctite 601 (UCL)
■ Low temperature grease (ball bearing grease) GULF-718EP, Mobil-Grease 28, SHELL-
Aero Shell Grease 22 or similar
■ Locking device for the motor-drive (delivered with the unit)
3. Repairs and adjustment