Thread: Hobby Issues
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Unread 09-04-2008, 17:26
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Re: Hobby Issues

Quote:
Originally Posted by Vikesrock View Post
Shouldn't power calculations be done with RMS voltage and current?
Yes, that is correct, because the heat generated is not constant but pulsed, and the important factor is the average power not the peak.

RMS is a mathematical construct used with sinusoidal signals to account for the 'real world' effects of such non-constant voltages. Using RMS in this calculation is good engineering practice.

On the other hand, I doubt the meter is really measuring RMS, more likely just 'close enough'. And that's OK.

Also, in the LED specs, it states the max reverse voltage is 5~6 volts? I'd pick the lower (5) and make sure you manage that. Put a regular 1N400x diode in series to half-wave rectify it (turning it into pulsed DC) and don't subject the LED to any reverse voltage.

Don
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