Transformerpreventive maintenance- an activity that rewards
The importance of power in our routine life and the hazardsof power failure would well explain the importance of transformer preventivemaintenance. Transformermaintenance is considered as profit, since it not only cuts the repaircosts, but also adds to the efficiency and the produce.
Monitoring different aspects of the transformer inappropriate intervals comprise transformer preventive maintenance, whosebenefits are abundant. Different aspects of transformer preventive maintenance isconducted daily, monthly, quarterly, half yearly and annual basis.
Oil basedtransformers
Transformer oil purification and transformer oil filtrationare included in transformer preventive maintenance steps and enhanceoperations. When the transformer oil acts as an effectual coolant, it ensuresthe apparatus to with stand stress that occurs due to heavy loading and shortcircuit.
Oil being the popular insulating fluid is scrutinized forpresence bi products such as sludge and acid formation, so that the flow is notinterrupted. Such bi products result in breakdown, whose consequences are heavyto bear. Transformer oil must be monitored twice a year for impurities, flashpoint, DDA and resitivity.
The electric, chemical and physical attributes of oil areprobed to ensure transformermaintenance. The dielectric dissipation attributes contribute to theresistance of transformer in higher temperatures. Monitoring the transformeroil in this regards, saves huge expenses.
The moisture content of the transformer oil is included inits chemical characteristics. When cellulose paper insulation absorbs thismoisture, insulating properties receive a beating which results in damage ofthe equipment.
When oxygen in the atmosphere comes in contact with the oil,it results in acid formation which results in ageing and transformer failure.In another probability, where tension occurs between water surface and oil, theflash point and pour point are affected making the fluid inflammable andaffecting its viscosity.
The BDV or breakdown voltage throws light on the presence ofcontaminants in the transformer, if any.
Checklist for oiltransformers
Checking oil levels in the main tank and conservator tank,replacing silica gel when colour becomes pink and detecting leakage and sealingthem are three main steps which are a part of transformer preventivemaintenance. The oil level in silica gel breather is checked once monthly sothat proper breathing is ensured. Besides checking the working condition of oil, training concerned staff is a part of transformer preventive maintenance.
Checklist for drytype transformers
Transformerpreventive maintenance for dry type transformers are performed mostly afterthe equipment is de-energized.
Visual inspection is an important part of transformerpreventive maintenance in dry transformers. The screens and coils arescanned for dust and such dust is vacuumed out. The apparatus should be scannedfor dust presence once quarterly or half yearly.
While chemical cleaners are avoided, vacuum or compressedair is used without direct contact with components. Rust and decolouration areclues for damage in dry type transformers.
Conclusion
On a concluding note, routine activities such as regularinspection, adjusting spare parts and following instructions religiously contributeto transformermaintenance. When such activities are properly executed, the equipment ismore efficient with mitigated expenses.
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