<div dir="ltr">That's a good point. If you increased the voltage from 5V to 15V, you could put 7 leds in series with a single 91 ohm resistor and reduce current comsumption by 1/7 or around 1A. This would also reduce heat produced from 7x5=35W to 1.134 x 15 = 17W, making the whole thing much cooler too.<div>
<br></div><div>7*1.6=11.2 (combined forward voltage drop for 7 LEDs in series at 1.6V each).</div><div>15-11.2= 3.8 (voltage across the resistor)</div><div>3.8/91=0.042A (current through each resistor / each LED)</div><div>
188/7=27 (resistors / branches required - you would actually end up with 189 LEDs since 27*7=189)</div><div>0.042*27=1.134A (total current required)</div><div>1.134 * 15 = 17W (total power)</div><div><br></div><div><br></div>
<div><br></div></div><div class="gmail_extra"><br><br><div class="gmail_quote">On Fri, Jul 12, 2013 at 8:36 AM, Chris de Groot <span dir="ltr"><<a href="mailto:cdegroot@adobe.com" target="_blank">cdegroot@adobe.com</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="auto"><div>Depending on how consistent you need the output of the IR LEDs you can always put two or three in series and reduce the size if the resistor, this would reduce the over amps used and make the whole thing more efficient.</div>
<div><br></div><div>C<br><br>Sent from my iPhone</div><div><div class="h5"><div><br>On 2013-07-11, at 5:55 PM, "Michael Grant" <<a href="mailto:michael@krazatchu.ca" target="_blank">michael@krazatchu.ca</a>> wrote:<br>
<br></div><blockquote type="cite"><div>That's almost 9 amps ... <br><br>Michael<br><br><br><div class="gmail_quote">On Thu, Jul 11, 2013 at 7:42 PM, Britta Evans-Fenton <span dir="ltr"><<a href="mailto:technical@artengine.ca" target="_blank">technical@artengine.ca</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr">sorry that was a Maybe I AM drawing too many Amps. (thanks for the help Darcy)</div><div class="gmail_extra">
<div><br clear="all"><div><div dir="ltr"><div><div>Britta<br></div><i>Technical Coordinator </i><br></div>
<a href="http://Artengine.ca" target="_blank">Artengine.ca</a><br><div><div><br>Ottawa Mini Maker Faire<br>Aug. 31 & Sept. 1 2013<br><a href="http://www.makerfaireottawa.com" target="_blank">www.makerfaireottawa.com</a><br>
@MakerFaireOTT<br>#MMFO</div></div></div></div>
<br><br></div><div><div><div class="gmail_quote">On Thu, Jul 11, 2013 at 4:41 PM, Britta Evans-Fenton <span dir="ltr"><<a href="mailto:technical@artengine.ca" target="_blank">technical@artengine.ca</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">Maybe I'm drawing too much Amps. Would you recommend this AC converter over the last one: <a href="http://www.digikey.ca/product-detail/en/LS150-5/285-1817-ND/1918828" target="_blank">http://www.digikey.ca/product-detail/en/LS150-5/285-1817-ND/1918828</a><div>
<br></div><div>I would have Amps to spare on this one.</div></div><div class="gmail_extra"><div><br clear="all"><div><div dir="ltr"><div><div>Britta<br></div><i>Technical Coordinator </i><br></div><a href="http://Artengine.ca" target="_blank">Artengine.ca</a><br>
<div><div><br>
Ottawa Mini Maker Faire<br>Aug. 31 & Sept. 1 2013<br><a href="http://www.makerfaireottawa.com" target="_blank">www.makerfaireottawa.com</a><br>@MakerFaireOTT<br>#MMFO</div></div></div></div>
<br><br></div><div><div><div class="gmail_quote">On Thu, Jul 11, 2013 at 4:32 PM, Britta Evans-Fenton <span dir="ltr"><<a href="mailto:technical@artengine.ca" target="_blank">technical@artengine.ca</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">There are 188 IR leds: <a href="http://www.digikey.ca/product-detail/en/QED233/QED233-ND/187410" target="_blank">http://www.digikey.ca/product-detail/en/QED233/QED233-ND/187410</a> All connected in parallel each with their own Resistor ( 91 OHM 1/4W 5% CARBON FILM)</div>
<div class="gmail_extra"><div><br clear="all"><div><div dir="ltr"><div><div>Britta<br></div><i>Technical Coordinator </i><br></div><a href="http://Artengine.ca" target="_blank">Artengine.ca</a><br><div><div><br>Ottawa Mini Maker Faire<br>
Aug. 31 & Sept. 1 2013<br>
<a href="http://www.makerfaireottawa.com" target="_blank">www.makerfaireottawa.com</a><br>
@MakerFaireOTT<br>#MMFO</div></div></div></div>
<br><br></div><div><div><div class="gmail_quote">On Thu, Jul 11, 2013 at 4:00 PM, Ken <span dir="ltr"><<a href="mailto:klmckinnon@rogers.com" target="_blank">klmckinnon@rogers.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
<div>It should power a LOT of LED's. How
many were you using and what sort of current limiting resistor did
you have....a quick circuit diagram would tell a lot.<br>
<br>
Ken<div><div><br>
<br>
On 7/11/2013 6:49 PM, Britta Evans-Fenton wrote:<br>
</div></div></div>
<blockquote type="cite"><div><div>
<div dir="ltr">
<div>A little question about AC adapters. </div>
<div><br>
</div>
<div>I have an artwork that I did that I used an AC adapter to
get power. It was on for 4 days during a show, and I was
surprised on how hot it got. (I almost burned myself). I did
have duct tape on it holding it to the back of a wall, so that
may have been half the problem.</div>
<div><br>
</div>
<div>I'm showing the work again, but I'm wanting to make sure
everything is safe. I need to hide the adapter due to
aesthetic reasons, so I wanted to create a little white box
around it with air holes, and I was suggested a fan, although
it if it getting hot due to over working, adding another fan
might not be a good idea. </div>
<div><br>
</div>
<div>It is only a bunch of IR leds that it is powering, so I'm
surprised at the power I am needing. </div>
<div><br>
</div>
<div>any help would be very well appreciated. </div>
<div>
<blockquote type="cite" style="font-family:arial,sans-serif;font-size:13px">
<blockquote type="cite"><br>
</blockquote>
<blockquote type="cite">Here is the Adapter I used : <br>
</blockquote>
<blockquote type="cite"><a href="http://www.digikey.ca/product-detail/en/VGS-25-5/102-1928-ND/2045659" target="_blank">http://www.digikey.ca/product-detail/en/VGS-25-5/102-1928-ND/2045659</a><br>
</blockquote>
<blockquote type="cite"><br>
</blockquote>
<blockquote type="cite">Here are the IR LEDS:<br>
</blockquote>
<blockquote type="cite"><a href="http://www.digikey.ca/product-detail/en/QED233/QED233-ND/187410" target="_blank">http://www.digikey.ca/product-detail/en/QED233/QED233-ND/187410</a><br>
</blockquote>
<blockquote type="cite"><br>
</blockquote>
<blockquote type="cite">And the Resistors I have on them
were 91 OHM 1/4W 5% CARBON FILM.</blockquote>
</blockquote>
</div>
<br clear="all">
<div>
<div dir="ltr">
<div>
<div>
Britta<br>
</div>
<i>Technical Coordinator </i><br>
</div>
<a href="http://Artengine.ca" target="_blank">Artengine.ca</a><br>
<div>
<div><br>
Ottawa Mini Maker Faire<br>
Aug. 31 & Sept. 1 2013<br>
<a href="http://www.makerfaireottawa.com" target="_blank">www.makerfaireottawa.com</a><br>
@MakerFaireOTT<br>
#MMFO</div>
</div>
</div>
</div>
</div>
<br>
<fieldset></fieldset>
<br>
</div></div><pre>_______________________________________________
Lab mailing list
1. subscribe <a href="http://artengine.ca/mailman/listinfo/lab" target="_blank">http://artengine.ca/mailman/listinfo/lab</a>
2. then email <a href="mailto:Lab@artengine.ca" target="_blank">Lab@artengine.ca</a></pre>
</blockquote>
<br>
</div>
<br>_______________________________________________<br>
Lab mailing list<br>
1. subscribe <a href="http://artengine.ca/mailman/listinfo/lab" target="_blank">http://artengine.ca/mailman/listinfo/lab</a><br>
2. then email <a href="mailto:Lab@artengine.ca" target="_blank">Lab@artengine.ca</a><br></blockquote></div><br></div></div></div>
</blockquote></div><br></div></div></div>
</blockquote></div><br></div></div></div>
<br>_______________________________________________<br>
Lab mailing list<br>
1. subscribe <a href="http://artengine.ca/mailman/listinfo/lab" target="_blank">http://artengine.ca/mailman/listinfo/lab</a><br>
2. then email <a href="mailto:Lab@artengine.ca" target="_blank">Lab@artengine.ca</a><br></blockquote></div><br>
</div></blockquote><blockquote type="cite"><div><span>_______________________________________________</span><br><span>Lab mailing list</span><br><span>1. subscribe <a href="http://artengine.ca/mailman/listinfo/lab" target="_blank">http://artengine.ca/mailman/listinfo/lab</a></span><br>
<span>2. then email <a href="mailto:Lab@artengine.ca" target="_blank">Lab@artengine.ca</a></span></div></blockquote></div></div></div><br>_______________________________________________<br>
Lab mailing list<br>
1. subscribe <a href="http://artengine.ca/mailman/listinfo/lab" target="_blank">http://artengine.ca/mailman/listinfo/lab</a><br>
2. then email <a href="mailto:Lab@artengine.ca">Lab@artengine.ca</a><br></blockquote></div><br></div>