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Dual Run Capacitors for DIY RPC?

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Investigator

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#1
I'm looking at options and need to know if I can use dual run capacitors in place of typical run capacitors in an RPC build.

I think I can, by just connecting two wires, and not hooking up to the smaller uF terminal on the cap.

Am I correct that a 30/5 uF dual run capacitor will have 30 uF hooked up to HERM and COM, and that it will have 5 uF hooked up between F and Com? So I could use a dual run and only use 2 of the connections on top?
 

GA Gyro

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#2
Yes, that is correct... I would only use 440V rated caps... or higher if you find them.

Having said that: HVAC and refrigeration grade run capacitors are not the best quality... I would have a couple of spares available.
You can also connect the 30 + 5 together, along with the common, and have a 35uF cap.
OTOH... not using the 5 segment, probably would put less load on the cap.
 

Investigator

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#3
Yes, that is correct... I would only use 440V rated caps... or higher if you find them.

Having said that: HVAC and refrigeration grade run capacitors are not the best quality... I would have a couple of spares available.
You can also connect the 30 + 5 together, along with the common, and have a 35uF cap.
OTOH... not using the 5 segment, probably would put less load on the cap.
How do you tell the difference in HVAC/Refrigeration grade capacitors?
 

GA Gyro

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#4
Most of the 'run' caps (single and dual value) I see, are HVAC/refrigeration quality (mass produced and sold very price competitive.
Start caps seem to be better quality.

IMO... this is a place to 'buy American'... :)
As the cheap ones (read that low quality) are almost always from a place which is in a significantly different time zone than we are... grin!
 
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