ONAN, ONAF and OFAF decide how much a transformer can actually carry. Learn how temperature rise, cooling class and ambient conditions set the real capacity.
How to plan and witness a distribution transformer factory acceptance test: the test programme, what to verify, documentation and how to close out issues.
What to check during a distribution transformer factory inspection: materials, process records, workmanship, testing, documentation and pre-shipment checks.
How to write a distribution transformer specification: ratings, standards, construction, losses, tests, documentation and the clauses that prevent site problems.
Calculate transformer load from measured current, convert between amps, kVA and kW, work out load factor and decide whether your transformer is correctly sized.
Typical distribution transformer service life, what actually limits it — insulation ageing, heat, moisture, overload and power quality — and how to extend it.
How distribution transformers are protected: fuses, relays, Buchholz, pressure relief, temperature monitoring, and how protection coordinates with MV switchgear.
Which tests a distribution transformer should pass: routine tests on every unit, type tests for new designs, FAT and site acceptance testing before energisation.
Distribution transformer installation guide: foundations, clearances, ventilation, cable termination, earthing, pre-commissioning checks and energisation.
Distribution transformer maintenance: inspection intervals, oil testing, cleaning, connection checks, thermography and condition monitoring for long service life.