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Hey, I just found a pot from some old electronic, and unsoldered it. The only numbers it has on it is B50k. So I know it's a 50k pot, but what about the other stuff? How can I know the max voltage, how can I know the max amount of amps it can handle before sizzling?

Thanks!

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## 7 Replies

steveastrouk (author)2013-02-22

You can't.

Pots should NEVER be used for power handling anyway. Reckon on 100mW MAX

HavocRC (author)2013-02-22

So I shouldn't use it as a variable power source? I was thinking to use it to output a variable voltage from 0v 12v and up to 1 amp max. ?? Not good? Then what should I use??

HavocRC (author)2013-02-22

Sorry, I'm don't understand what power is! Switches are measured in the max amount of voltage and amps. Pots are measure in mW. What does this mean?

steveastrouk (author)2013-02-22

Pots are resistors. Switches are designed to have very very low resistance.

The thing that destroys resistors is EITHER because they can't resist the voltage across them, or they get so hot they melt on the load you want to run in them, so we are more interested in power DISSIPATION than anything else.

HavocRC (author)2013-02-22

Hmm, ok. I'll have to find somewhere to read up on that. Thanks!

steveastrouk (author)2013-02-22

Power is the rate of release of energy. Mathematically for a device carrying current I and voltage V across it, Power = I x V

Steve

steveastrouk (author)2013-02-22

You use an adjustable voltage regulator, like the LM317. You set the voltage by using a pot, sure, but the main current doesn't flow through it. Like this: