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Pfaff sewing machine capacitor

Vosmire

Mar 9, 2017
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hi, I'm repairing a sewing machine that I've bought as a spares or repairs project. As anticipated the motor capacitor has blown, spewing out its contents. Before buying a replacement motor I'd like to see if there was a cheaper way of getting it working. It's probably a 60's or 70's era machine - Pfaff 97. I've attached a photo of a similar capacitor from the internet. I'm pretty certain that it's the same as that blown in mine. The specs of capacitors are way over my head so my question to the forum is this. Is there a modern replacement that I could solder in to replace it? Thanks in advance.
 

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duke37

Jan 9, 2011
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If this is a filter in the input supply, then the motor will work without it. Its purpose is to reduce radio interference which the sparks at the commutator produce.

Check the motor before buying a new filter.
 

Alec_t

Jul 7, 2015
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That looks like an interference supressor which includes four capacitors in one package. You could replace it with suitable X- and XY-rated individual caps.
 

Vosmire

Mar 9, 2017
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Hi, thanks for the replies. I went to Maplin today and they didn't have anything appropriate. Is there any chance someone in this forum could give me any pointers for sourcing the right parts?
Again, thanks
 

Alec_t

Jul 7, 2015
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The capacitance values are shown in the pic, as is the 250VAC rating (but a higher rating woud be better). Use an X-rated cap if it connects between line and neutral. Use a Y-rated cap if it connects between either line or neutral and ground (motor frame). You will need to trace the wiring to see what goes where.
 

Vosmire

Mar 9, 2017
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Thanks for your help. I've attached the photo of the actual motor now. Best regards.
 

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Minder

Apr 24, 2015
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I seem to recall as similar post recently on an identical problem, unless it was another site.
It is a Universal motor, and as such kicks out a lot of (electrical) noise, you can make up a filter/snubber with individual caps, ensure you use AC rated caps as used in PSC AC motors.
M.
 

Vosmire

Mar 9, 2017
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Thanks for your replies. I actually found a place in Germany selling the 'Kondensator' bonded to the bracket that mounts onto the motor. It was marginally less than a whole motor replacement which is what I ended up buying.
 
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