ABB UC Series - Default Chapter; Table of Contents

Contents
1. Introduction _______________________________________________________9
1.1 General _______________________________________________________9
1.2 Repair categories _______________________________________________9
1.3 Serial number __________________________________________________11
1.4 Spare parts list _________________________________________________11
1.5 Maintenance guide ______________________________________________12
1.6 Tightening torque _______________________________________________12
2. Trouble-shooting ___________________________________________________13
2.1 On-load tap-changer ____________________________________________13
2.2 Pressure relay __________________________________________________14
2.3 Motor-drive mechanism __________________________________________15
2.3.1 Control system _____________________________________________15
2.3.2 Power system ______________________________________________17
2.3.3 Miscellaneous ______________________________________________17
3. Repairs and adjustments ____________________________________________22
3.1 Replacement of gear box on the on-load tap-changer or
replacement of o-rings for the gear box ________________________________22
3.1.1 General ___________________________________________________22
3.1.2 Tools required ______________________________________________22
3.1.3 Material and spare parts required ______________________________22
3.1.4 Procedure _________________________________________________23
3.2 Replacement of diverter switch housing cover gasket ________________27
3.2.1 General ___________________________________________________27
3.2.2 Tools required ______________________________________________27
3.2.3 Material and spare parts required ______________________________27
3.2.4 Procedure _________________________________________________27
3.3 Restoring the gas cushion _______________________________________28
3.3.1 General ___________________________________________________28
3.3.2 Equipment required _________________________________________28
3.3.3 Procedure _________________________________________________28
3.4 Replacement or addition of a multi-position switch (BUL only) __________30
3.4.1 General ___________________________________________________30
3.4.2 Tools Required _____________________________________________30
3.4.3 Procedure _________________________________________________30
3.5 Examination of the diverter switch after a pressure relay trip ___________32
3.5.1 Tools and material required ___________________________________32
3.5.2 Procedure _________________________________________________32
3.6 Tests of the pressure relay ________________________________________33
3.7 Replacement of pressure relay ___________________________________34
3.7.1 General ___________________________________________________34
3.7.2 Tools required ______________________________________________34
3.7.3 Spare parts required ________________________________________34
3.7.4 Procedure _________________________________________________34