<div dir="ltr">The resistance of a tungsten incandescent lamp filament<div>changes roughly 10:1 from hot to cold.</div><div><br></div><div>A 40W lamp at 120 V is passing 1/3A,</div><div> so its hot R is ~ 360 ohm, so cold R could be estimated at ~ 36 ohm.</div><div>I just measured one, got ~ 27 ohm (cellar workshop, below normal room temp)</div><div><br></div><div>What level do you need to run the practical at,</div><div>and how long does it stay on for ?</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, May 3, 2018 at 12:37 PM, Jon Ares via Stagecraft <span dir="ltr"><<a href="mailto:stagecraft@theatrical.net" target="_blank">stagecraft@theatrical.net</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">Howdy folks.... I occasionally come to the challenge of using an LED<br>
practical on stage (like a light bulb) and I run a dummy load<br>
incandescent on the same dimmer when possible.... but sometimes, like<br>
now, I don't have a reasonable, practical way to do that, as I can't<br>
have a visible incandescent bulb visible anywhere near the "open air"<br>
practical - and it's not... practical... to run a dummy load bulb 50+<br>
feet offstage...<br>
<br>
Wouldn't it be possible to just wire in an appropriate-sized resistor?<br>
I know it would get warm, but I've got lots of open air (don't need<br>
to enclose the resistor) - but not finding any definitive info online.<br>
Lots of queries from people trying to get their kitchen LED cans to<br>
work, and the responses are usually "Why don't you just buy a dimmer<br>
switch rated for LEDS?" Not helpful in my situation....<br>
<br>
Thoughts? What size resistor would be necessary to fake a few watts?<br>
<span class="HOEnZb"><font color="#888888"><br>
-- <br>
Jon Ares<br>
<a href="http://www.arescreative.com" rel="noreferrer" target="_blank">www.arescreative.com</a><br>
<br>
______________________________<wbr>______________________________<br>
For list information see <<a href="http://stagecraft.theprices.net/" rel="noreferrer" target="_blank">http://stagecraft.theprices.<wbr>net/</a>><br>
Stagecraft mailing list<br>
<a href="mailto:Stagecraft@theatrical.net">Stagecraft@theatrical.net</a><br>
<a href="http://theatrical.net/mailman/listinfo/stagecraft_theatrical.net" rel="noreferrer" target="_blank">http://theatrical.net/mailman/<wbr>listinfo/stagecraft_<wbr>theatrical.net</a><br>
</font></span></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div><div dir="ltr"><div>...Dan Sheehan<br>Fixer of things that break</div><div>TD Walpole (MA) Footlighters<br><br></div></div></div></div></div></div></div>
</div>