Dimming cheap fake candles...

[jtara92101]

A bit of an oddball topic, and not specifically UDI... But sometimes things that you wouldn't think would work, work... And that's useful to know!

 

I have a large metal sculpture on a wall. It's a "tree", make of rebar and sheet metal. The artist is very talented at repurposing metal! It has a number of candle holders, which can take real or fake candles.

 

I got a bunch of those fake LED candles at CVS, drilled holes in them, and wired each with thermostat wire (no more batteries!) and put a connector on each. I got a cheap multi-voltage wall-wart at Fry's and used it as a power supply. I can vary the brightness by changing the voltage switch.

 

I wondered if a LampLinc could dim it.... and it can! In fact, works way better than any fancy dimmable LED bulb!

 

I set the wall wart to 9V - it will go to 12, but don't want to push it. I seem to get full dimming range, rather than the limited range of LED bulbs.

 

This was an experiment with an old 2-pin powerline-only Lamplinc. I plan on replacing it with a dimmer outlet now (for neat installation) and then get the smallest 9 or 12V wall wart I can find.

[Brian H]

Be extremely careful by doing this.

 

Using a dimmer on a wall wart that is not specified for use with a dimmer. Is not safe to do.

It can result in poor performance or a short life of the wall wart and possibly the dimmer.

Possible release of smoke and flames after being On for a period of time.

Makes power line noise when On and stops any Off commands from working.

 

Until you are very confident the setup will work. Observe it for strange noises, electronic smells and overheating of the wall wart.

 

I have seen users report melted or short lives with wall warts. When on a dimmer even ones where they where always set to 100% On.

 

A different combination of parts. Like an OutletLinc Dimmer in place of the LampLinc.  A smaller wall wart for the one you are using now. Could get you a completely different way the setup works. Than what you tested with.

[apostolakisl]

They do make dimmable 12v transformers.  The only question is whether they will work with such a tiny amp draw.  The ones I am familiar with are intended for 12v halogen lights and thus are designed for a lot more watts than the draw of your leds.

[jtara92101]

Now I fell bad about not urging caution... I do have quite a bit of electronics background (got my ham license in high school, and actually 8 semesters of electrnics in high school... but went into Computer Science in college) so I knew what I was looking for.

 

I didn't think it would work myself, but decided to try it anyway... I'd assumed it was a regulated power supply, and would simply maintain constant output voltage until the input dropped below the requirement of the regulator. But I was willing to be surprised - and was! I was willing to use a relay module if the dimmer didn't work out.

 

But from what I see, it is an unregulated power supply, and would not expect this of the typical wall-wart.

 

FYI, the wall wart in question is a LKG Industries (Philmore) model BE226. It's one of the ones with a slide switch, with 1/5/3/4.5/6/7.5/9/12V. It says 12v 300mA max.

 

(Looked up online, was not able to get much in the way of details...)

 

Was surprised as heck that it dimmed FULL RANGE on the dimmer! No strange sounds, cut-outs, etc.

 

The sculpture has 9 of those little single-led tea candles that normally run on a button cell.

 

Think now I will forget about getting a replacement wall wart, since I have one that's working! It's actually a pretty compact and reasonably non-ugly. If I do get a replacement, I'll shop carefully and make sure I get one that I can see a schematic for. It was a good one, too - a Lightech.

 

Yes, I know about the 12V dimmable transformers. I used them at my old place for under-counter halogens. I doubt my sculpture would draw enough current for it, and they don't provide full-range dimming. And, to boot, the Insteon dimmer wasn't very happy with it.