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8100 PSU failure MagneTek
Posted by: mitchW on 2014-12-02 14:05:37
I recently acquired two 8100s with blown PSUs. One had a Delta, which I also described in other topic. The second has a MagneTek PSU (Made in Italy), which is also blown. I have never seen a PSU made by this company, and it looks cheap compared to Delta. It was also all riveted together, so I had to drill the rivets out. But this one is almost literally burned, see the pictures below.

The fuse is still intact, but the damage is quite severe. However it looks like it just got incredibly hot, but nothing really flamed up. I counted at least 4 dead capacitors (ESR way off), 1 heat damaged resistor, 1 blown power supply IC and two blown MOSFETS (STM P5NA80), but there could be more damage in other components.

Now I wonder why it actually failed in such catastrophic way. I believe that electrolytics must have dried up and ramped up the other components to their limits.

What do you think? Is it fixable? I guess that it probably is, but without a schematics it would probably be impossible.

2014-12-01 16.42.16.jpg

2014-12-01 16.42.32.jpg

2014-12-01 16.42.38.jpg

2014-12-02 20.00.12.jpg

2014-12-02 20.10.57.jpg

2014-12-02 22.57.21.jpg

2014-12-02 22.57.48.jpg
Posted by: techknight on 2014-12-02 15:11:28
That one looks lightning damaged.
Posted by: rsolberg on 2014-12-10 19:46:41
I was trying to remember where I knew MagneTek from. They were a major manufacturer of RV converters/inverters/chargers and AC/DC distribution panels at one point. I've seen the name on industrial power controls as well.
Posted by: Elfen on 2014-12-11 09:15:35
That one looks lightning damaged.
I was thinking of the same thing, Techknight.

Question is, did it sacrifice itself and saved the board?
Posted by: techknight on 2014-12-11 09:38:25
Doubt it. There is probably lots of damage. Side note:

MagnaTek designed power supplies for infocus projectors and thier rebrands. They are horrible and will self-destruct taking out multiple components spontaneously.

These were so bad for that, in fact I built a business by repairing thos power supplies and made a living at it... That lasted while before the economy tanked.
Posted by: Hotdog Zanzibar on 2015-01-09 14:27:17
That board looks pretty cooked. I'd say odds of rescue are thinner than soup skin.
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