Author Topic: SCR max current ?  (Read 773 times)

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Offline lordvader88Topic starter

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SCR max current ?
« on: February 22, 2019, 11:25:03 pm »
I don't own any SCR (that I know of) but I want some to try a crowbar circuit in an adjustable linear PSU. Checking ebay they start at 400V, 2A. I'm wondering if your max voltage is way way way lower, say 12V, can u go way over the 2A current max ? How is power calculated in these ?
 

Offline dmills

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Re: SCR max current ?
« Reply #1 on: February 22, 2019, 11:41:07 pm »
That's not the way any switching device works!

An SCR is (simplifying outrageously) either non conducting in which condition it stands off lots of volts but passes essentially zero current, or conducting in which case the voltage is 1V or so and however much current is required to make that be a thing flows.

Rule of thumb : Each maximum rating is independent, you need to satisfy all of them at all times.

Now there are some parts that operate in the linear region, where things can get even more complex and there are some other limits that can be quite a bit lower then the ones on the front page of the datasheet that must also be complied with.... (And SCRs I would note have some dynamic limits as well, things like a maximum dI/dt value).

Regards, Dan.
 

Offline Totalsolutions

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Re: SCR max current ?
« Reply #2 on: February 22, 2019, 11:48:30 pm »
2Amps is 2 Amps. 400volts is the upper voltage limit the poor little device will hold back. So your 12 volts is ok in spec.
Paul
 


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