An interturn short circuit is difficult to detect with a conventional multimeter - the difference in resistance is small. Let's look at how to find an inter-turn short circuit reliably.
Why it is difficult to find
When several turns are short-circuited, the phase resistance changes slightly, and a defect cannot be identified by simple continuity testing. Special methods are needed.
Search methods
| Method | What it shows |
|---|---|
| Comparison of phase resistance | Underestimated in the defective phase |
| Current measurement by phases | Warp current |
| Thermal imager | Local overheating at the short circuit location |
| A device for checking turns (surgical test) | Accurate detection |
Practical approach
- Measure the resistance of all phases and compare - the defective one will be slightly below.
- Check the current in phases under load - there will be a imbalance.
- Use a thermal imager to find local overheating.
- For accuracy, use a special device (surgical tester).
Indirect signs - local overheating, increased current, loss of power. For accurate diagnostics, special devices are needed, which are used for professional winding diagnostics.
What to do
An interturn short circuit can only be eliminated by rewinding - partial repair is impossible. The earlier the defect is identified, the lower the risk of complete combustion and damage to the iron.
Do you suspect an interturn short circuit in Tashkent? Elektromotors engineers will carry out accurate diagnostics and rewinding - leave a request.