breakdown voltage transformers lifespan coolant crucial dielectric strength greatly increase performing processes technical side electrical maintenance greater noida significantly impact dissolved gases impurities extending moisture gases reliable operation importance heres rrr electricals filtration process oil filtration transformer oil oil filtration process rrr electricals states core service catering transformer oil filtration emphasize oil filtration impede oil circulation search results heres maintaining transformer reliability regular transformer repair highlight key aspects mohan nagar ghaziabad