250VAC Run Motor Capacitor

[JuniperSprouts]

I know what capacitors do, in theory, but I do not have a real-world/application knowledge of (motor) run capacitors.

I am replacing a 10uF +/- 5% 250VAC (motor run) capacitor that popped in my bench grinder. Man, did that bang scare me! I found, in my box of capacitors, the following new cap: 12.5uF +/- 5% 250VAC (Motor)
(They are both big, cylindrical types, roughly 30mm diameter x 70mm height...roughly the size of the size D batteries)

Can I use it? Is there a general rule-of-thumb to remember for such?

The new one is the same as:
http://www.westfloridacomponents.com...L-2EJ012E.html

The old one just has the specs (I listed) & model #: CBB25
(The only CBB25's I was able to find on the web were definitely different...miniscule capacitance & box-type.)

[999999999]

Re: 250VAC Run Motor Capacitor

The general rule is replace with same uF value and equal or higher voltage rating. The 12.5uF will probably work fine but may make the motor run a bit hotter. You don't necessarily need the same part #, just a typical 10uF film cap in a size you can mange to strap on where it goes, and of course the right terminal type of you don't want to rig new connectors.

Personally if the bench grinder isn't a high end/expensive model, I'd use the 12.5uF you already have, but ideally it should be another 10uF.

[sam_sam_sam]

Re: 250VAC Run Motor Capacitor

Look at this site they have one for about $7.50 the right UF value 10 uf @ 250 volts AC

http://store.eurtonelectric.com/capa...0uf250vac.aspx

[999999999]

Re: 250VAC Run Motor Capacitor

You might also enquire at HVAC supply houses locally, 10uF motor caps are fairly common in HVAC systems though usually in 450V value, which of course will be physically larger. I was really surprised that I found one locally for only $8 or so the last time one crapped out on my A/C, and even more surprised when the guy who sold it to me turned out to be an old friend I hadn't seen in over 20 years.

[JuniperSprouts]

Re: 250VAC Run Motor Capacitor

Thank you for the input, guys.