Motor run capacitors.

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pre65
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Motor run capacitors.

Post by pre65 » Sun Nov 12, 2017 12:40 pm

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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Re: Motor run capacitors.

Post by IslandPink » Sun Nov 12, 2017 12:57 pm

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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Re: Motor run capacitors.

Post by Nick » Sun Nov 12, 2017 1:17 pm

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

Post by IslandPink » Sun Nov 12, 2017 1:23 pm

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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Re: Motor run capacitors.

Post by IslandPink » Sun Nov 12, 2017 1:26 pm

Bigger datasheet but nothing either -
http://datasheet.octopart.com/97F5706-G ... 084154.pdf
"I don't care, I don't care, I don't care if he comes round here, I've got my beer in the sideboard here"

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