6.3 START UP
• Before start up, satisfy of conditions of 6.2.1 and 6.2.2
• Make sure that all equipments, except transformer, are adjusted max value of voltage or
current and choosen properly.
• All electrical connection must be checked by authorized personnel.
• Safety zone must be allocated while energizing transformer and all living creatures must be
taken out of zone.
• First energizing of the transformer must be operated off-load. After inspecting the usual
conditions of noise level, temperature and oil level; the transformer would be loaded.
7. OPERATING AND MAINTENANCE
Transformers do not require any particular maintenance. However, to guarantee good operation,
a few periodic checks should be carried out as follows.
• Oil level and oil leakage should be observed periodically. In case any decrease in oil level,
- If transformer is conservator type; refined oil with the same specifications should be added.
Oil leakage must be prevented with proper procedure.
- If transformer is hermetically sealed, the manufacturer should be informed as soon as possible.
• Dehydrating breather should be checked; in case of malfunctioning, it must be replaced. (for
conservator type transformers)
• Buchholz Relay should be checked periodically. If there is gas accumulation, it must be
released after the reason is detected. Functions of relay should be controlled annually.
• Oil temperature should be checked through thermometer; if there is overheating, reasons
should be detected.
• Grounding resistance should be checked annually. (It must not exceed 5 Ω.)
• Maintenance and inspections should be carried on while transformer is de-energized.
• Bushings always should be cleaned and their physical status should be properly checked.
• In case of breaks and cracks in bushings, please contact with the manufacturer for
replacement. Bushing should be stocked in vertical position and dry conditions.
Ulusoy Distribution Transformers Maintenance, Operation, Installation and Instruction Manual