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Jeff Wisnia Jeff Wisnia is offline
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Default Run versus Start Capacitors - How to tell


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.


* From "Bad Man's Ballad" - Kingston Trio - ca 1960

Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.