ABB VUBB User Manual

Also see for VUBB: Installation and commissioning guide User guide

ABB VUBB User Manual Manual pdf 32 page image

32 User’s guide VUBB | 1ZSC000562-AAL en6. TroubleshootingThis chapter provides information used to locate faults on thetap-changer. Instructions for correcting faults, replacing parts,etc. are in Section 7.Error condition Troubleshooting procedureHigh oil level alarm A rising oil level in the tap-changer conservator may indicateleakage between the tap-changer and the transformer maintank.1. Make sure that the alarm is not due to overfilling uponcommissioning or maintenance. This can be checked byadjusting the oil level according to Section 3.5.3.2. Recheck the oil level later.Low oil level alarm A low oil level in the tap-changer may indicate leakage.1. If there is no visible leakage, adjust the oil level according toSection 3.5.3.2. Check the oil level later.Pressure relay has tripped For troubleshooting instructions regarding the pressure relay,see the assortment guide.Note the number of operations and then lift the tap-changerinsert. Inspect the tap-changer according to the maintenanceguide.The control system or the motor-drive mechanism ismalfunctioningFollow the instructions given in the separate guide for themotor-drive mechanism.Drying agent has changed color from the bottom of thebreatherDry or replace the drying agent.Drying agent has changed color from the top of thebreatherThere is a leakage in the connections to the conservator.Locate the leakage and seal it.CAUTIONDo perform service on the transformer after apressure relay trip; contact the manufacturer.