Motor run capacitors.

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pre65
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#1 Motor run capacitors.

Post by pre65 »

Accepted wisdom seems to be that the DC rating of motor run capacitors is AC volts X 1.4

So 440v AC X 1.4 = 616v DC

However, reading several articles on the Interweb there are suggestions that up to 2X the AC rating is still "safe".

Any comments ?
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IslandPink
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#2 Re: Motor run capacitors.

Post by IslandPink »

I look forward to any answers with interest because I was never brave enough to use a 2x or >2x rating myself, I always stuck to about 1.4 or 1.5 as the max. The 440's, I've heard in some places are OK to 1000v DC for instance.
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Nick
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#3 Re: Motor run capacitors.

Post by Nick »

I would just go by the makers spec sheet.
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IslandPink
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#4 Re: Motor run capacitors.

Post by IslandPink »

Nothing on this one about DC -
https://www.galco.com/techdoc/gecp/97f5300_dat.pdf
Will keep digging.
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IslandPink
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#5 Re: Motor run capacitors.

Post by IslandPink »

Bigger datasheet but nothing either -
http://datasheet.octopart.com/97F5706-G ... 084154.pdf
"Once you find out ... the Circumstances ; then you can go out"
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