Type basedtransformer preventive maintenance
The significance of transformers and its role in powerindustry needs no introduction. While on duty, transformers not only transmitpower, but also ensure safety of the equipment at different voltage levels. The size of the transformers might vary according to their residential and industrial uses, but the importance of transformermaintenance is the same irrespective of its volume.
Transformers are maintained in two perspectives namelytransformer preventive maintenance and transformer maintenance based onrequirement. Be it oil based transformer or dry type, the staff are trained in transformer maintenance appropriately.
Oil basedtransformers
In the case of oil transformers, proper installation andoperations are ensured. Care is taken not to overlook basic requirements whichcould grow up to serious damages when let neglected.
The staffs are tutored about probability of trouble shootingcertain anticipated conditions, which are grouped together as unscheduledmaintenance.
Visual inspections followed by repairs, adjustments andreplacements are regular transformer preventive maintenance. The transformermaintenance predicts damages and corrects the faults that lead to suchdamages so that things do not go out of control.
The temperature, devices, insulation systems, protective coatingsof the transformer are brought under observation.
For low insulation resistance, earth fault or absence ofprimary voltage could be the reason and position or connection should bechecked. For spurious triggering during operations, the sensors and thermometers should be studied.
Dry type transformers
Ventilation and atmospheric conditions are importantcriteria of dry type transformers because any leakage or contact withatmosphere could turn disastrous. Proper ventilation ensures cooling in dry type transformers. Such ventilations are handled depending upon geographical locations where the transformers are installed.
Dry type transformers are usually installed in areas freefrom dust and chemicals. As a part of transformerpreventive maintenance, dry transformers above 75kV are positioned 12inches from walls and other transformers to ensure uninterrupted flow of airaround the apparatus. If located near combustible materials, minimum separations are determined by National Electric Code (NEC).
If significant noise is present in the location, it isconsidered while installing transformer there. In higher altitudes where airdensity decreases, the temperature is considered appropriately for transformer maintenance.
The dry transformer could complain low insulation resistancewhich occurs due to humidity in surface of windings. As transformermaintenance, clean dry air ventilation should be ensured. For unexpected secondary voltage, the position or connection should be altered.
Dry transformerpreventive maintenance is classified in two types namely in energized stateand de-energized state.
The alarm trips of the transformer must be taken seriouslyand the reasons should be immediately investigated.
Transformers andageing
Besides its type of insulation, transformermaintenance is distinct for ageing transformers. Transformers have a lifespan between 30 to 40 years based on the rate of deterioration. Few exceptionaltransformers could last only for 20 to 25 years.
Since electric surges are the most popular reasons fortransformer breakdowns, the same is prioritized in transformerpreventive maintenance.
Conclusion
The art of maintaining transformers according to itsinsulation is a very comprehensive science and must be fervently followed toextend the life span of the apparatus and the profits thus gained.
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