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Sam Goldwasser Sam Goldwasser is offline
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Default Sizing a Bench Grinder Capacitor

"w9gb" writes:

"leoJ" wrote in message
ups.com...

Homer J Simpson wrote:
"leoJ" wrote in message
ups.com...

Have a bench grinder that was given to me and runs fine if you spin it
up by hand - the capacitor is missing. Is there a way to determine what
size/part no. capacitor will work with a 115V 60Hz Single Phase motor?

HP?


3/4 HP, 3600 RPM


Likely a motor start capacitor.
http://www.cde.com/new/catalog/motorstart/

CDE motor start capacitor catalog page (download this - right mouse click -
Adobe Acrobat)
http://www.cde.com/catalogs/PSU.pdf

I am looking at a NOS Mallory motor start capacitor on my bench --
it is rated at: 108-130 mfd at 250 VAC

Application Guide
http://www.cde.com/catalogs/AEappGUIDE.pdf


If it's used only for starting.

Easiest test would be to spin it up by hand and then use a multimeter
to check for voltage across the wires where the cap would go. If you
see full line voltage, it's a run cap.

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