| Title | By | Posted On |
| Pancake transformer |
jimmyc |
4/18/2006 |
| I have here a pancake transformer. It is in a variable frequency drive. It is also at some very high temperatures. I believe we may have a partially shorted transformer. Does anyone come to the same conclusion? If not why not? would greatly appreciate feedback soon! |
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| Re:Pancake transformer |
jvoitl |
4/18/2006 |
| Several years ago I was asked to check some transformers that were also hot. The rated temperature rise on them was 140 degrees C. You're still below that so it may or may not be a problem. Best to contact the manuf. and find out the rated rise. |
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| Re:Pancake transformer |
jvoitl |
4/18/2006 |
| With a second look at the image, it appears the hottest area may where there is a wire connection. Could you insert a digital picture? |
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| Re:Pancake transformer |
neatster77 |
4/20/2006 |
| I would do a turns ratio test if you suspect the winding. |
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| Re:Pancake transformer |
jimmyc |
4/21/2006 |
Here is the visual you requested. I also think we could have a hot wire. There appears to be a connection running acros in that area.
Jim |
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| Re:Pancake transformer |
Laland |
4/21/2006 |
| Please check rated capacity of transformer and your load. It might be overloaded.. |
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| Re:Pancake transformer |
jvoitl |
4/24/2006 |
| The windings themselves appear cool. The visible image is not too clear, but the white wire that is hot in the IR image appears to have some special type of insulation. Possibly that area is hot by design. If all the connections there are tight and clean, I'ld check with the manuacturer. |
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| Re:Pancake transformer |
testtech |
5/1/2006 |
| Looks like normal heating to me. If the transformer were shorted to ground or between phases, it would no longer be hot. The time from short to failure in this winding would be brief. A short within a single phase of the winding might persist but should be reflected in unbalanced voltages. In any case, it should be detectable with micro-ohmmeter readings. The windings has relatively large air passages formed by the wood bracing around which the coils are formed. I believe you see the point of greatest convective heating transfer as your hot spot. |
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| Re:Pancake transformer |
electricpete |
5/14/2006 |
| I agree with testtech. |
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