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dpb dpb is offline
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Default Run versus Start Capacitors - How to tell

On Apr 18, 12:44 pm, Jeff Wisnia wrote:
Jeff Wisnia wrote:

... there really isn't any difference between a "run" and a "start"
capacitor, the term comes from the application, not the design.

I seem to recall that start caps are smaller and less expensive and rated
for less ripple current than run caps. For instance, Grainger's 4CU61 and
2GU30 caps have similar values and voltage ratings, but the 4CU61 costs
$8.26 vs $15.12, and it's only rated for 20 3-second starts per hour, ie
a 2% vs 100% duty cycle.



I'll stand corrected on the ripple current rating thing, which seems to
make sense.

If the OP really can't find the value he needsk he could get one of
these monsters which comes with jumpering instructions to replace
anything from a 12.5 to a 67.5 mfd capacitor, but it might be bigger
than the motor itself. G

I'm betting the OP's motor has a cylindrical paper covered cap under a
sheet metal "hump" on it's side.


But it could be (and w/ a drill press it's what I'd expect) just a
capacitor-start motor to provide the starting torque. I'm w/ John G
that OP's best bet is probably local motor repair shop and take the
one he's got w/ him. McMaster-Carr is another online source worth
checking if need be. The description on the case he posts makes me
bet it was/is Chinese-manufactured so unlikely will find exact
equivalent--and there probably aren't parts for the motor from Sears
for it listed as he's already found out -- although usually one can
see the complete parts breakdown on the Sears site though I didn't
look for his...