SIS desk lamp modding with 2x 50W Epistar LEDs

Julian Holtz

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Nov 4, 2005
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Germany
Well, the grounding worked, but only on one lamp. The other one "latches" itself in the "on" state, and does not switch off even when the SS relais is clearly off. Strange...

Meanwhile, I modified my lamps by using a cable with 4 strands instead of 3. So I can both have the 230V switch and the LEDs connected to the cable, without having to resort to using the body of the lamp for the LED current. This works as expected, but still, only one lamp works properly when the body is grounded. The other one still latches on. Oh well.
 

Julian Holtz

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Joined
Nov 4, 2005
Messages
343
Location
Germany
I have now done another iteration of my mod. I was tired of the solid state relais latching on, so I added a mechanical relais with snubber circuit and an NTC inrush current limiter. I also got hold of a power supply small enough to fit into the arm. This time, I used Citizen LEDs. For those, 1 power supply with 320mA is enough. To mod the lamp with the original LEDs, I'll take two power supplies if I can fit them in.
Here's the album:

http://imgur.com/a/R4grW

jLJlxxt.jpg
 

Julian Holtz

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Joined
Nov 4, 2005
Messages
343
Location
Germany
Thanks Jim! Yes, I made that too. I once found a handful of aluminium pieces in the scrap box of a former workplace. So after producing a large amount of chips on the drill press, I now have these gems for my desk. They also worked well to serve shots at last year's halloween party.:drunk:

http://imgur.com/a/mSb2D

Dm46giu.jpg


6ozN38F.jpg
 
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brickbat

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Dec 25, 2003
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Indianapolis
Ha! Very Cool. Thanks for giving me an idea for a few Christmas presents...

I'm surprised to not see a few Staedtler Triplus markers in there (my favorite markers...)
 

Julian Holtz

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Nov 4, 2005
Messages
343
Location
Germany
You're welcome. The Triplus seems interesting, ut I have never been much of a marker person. My textbook days are over since 2013 when I got my engineering technican degree, and my better pens (Pentel Graphgear 1000, Lamy fountain pen) rest in their pencil case since that day. Maybe I should use them more often. Thanks for that idea...:p
 

brickbat

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Indianapolis
Well, my engineering textbooks days have been over since 1983 :)

The Triplus pens are for fun, not drafting. I just like them for sketching, when I get tired of black and white...
 
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