#troubleshooting
6 posts filed under this tag, newest first.
Transformer running hot: harmonics and K-factor
The ammeter reads 70 % of nameplate and the transformer is too hot to touch. Why eddy loss follows frequency squared, and what K-factor really tells you.
7 min read
RCCB keeps tripping: how to find the leakage
Healthy loads leak. Six of them on one board can trip a 30 mA RCCB with nothing faulty anywhere. How to measure the standing leakage and what to change.
8 min read
Modbus RTU not responding: a diagnostic sequence
Timeouts, CRC errors and silent devices, worked from what you can observe. Two minutes with a multimeter settles the two commonest causes.
7 min read
Energy meter showing wrong readings: a checklist
Work out how wrong it is first — the size of the error names the cause. Ratio errors, reversed CTs, saturation and the ones that look plausible.
7 min read
Power factor still poor after fitting capacitors: why
The bank is installed, the contactors click, and the bill has not moved. Six causes, ranked, and the one clamp-meter test that finds most of them.
7 min read
MCCB keeps tripping: how to find out why
Time the trip first — it halves the search. Then work through overload, short circuit, earth fault and the causes that are not faults at all.
7 min read