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Tim Wescott Tim Wescott is offline
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Default Cap value for timing circuit

On Tue, 06 Oct 2009 22:42:57 -0700, DaveC wrote:

Relay-logic controlled printing machine, 110 vac.

A 300mfd (150v) electrolytic cap is used together with 25K (25 W) ohm
wirewound pot and a 5K ohm relay coil to control a variable time delay
before the relay opens.

The cap is shot (measures less than 1mfd). I'm having a hard time
finding a replacement locally. (Yeah, I know: Digi-Key, et al) But I
need to get this up and running today.

What other common types can I use in place of this can-type cap? (It has
2 wings that rivet to the sides of the opening in the chassis and solder
terms make the connection below the chassis.) Maybe poly-somethings, two
in series or parallel?

It's a Mallory FP119A.

Can I use a non-polar electro? (The wiring diagram shows a polarity
indicator.)

Or a motor-start cap? ::

http://tinyurl.com/y9d3ks6

Thanks,
Dave


On the face of it anything that'll get up to 330mfd and withstand 150V
should do. That's a honking big cap, and anything that's not a 'lytic
will probably be bigger.

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