Current SunPod LED's are dimmable

[bill-e]

Just wanted to let you know that the LED's on the SunPod are dimmable. When the ACJr actually sends out the dim commands they flash but that doesn't happen very often. I just plugged the transformer into a lamp module, works fine.

[dhoch]

You might want to reconsider... that transformer will go eventually (it's not meant to handle the variability that is used to dim the lights).

Dave

[bill-e]

Thanks for the warning but it's just a low voltage transformer, shouldn't be an issue.

[collins]

bille-e, dhoch is correct. I cooked 2 coralife moon lights before I realized why it wouldn't work - at least for long.

[bill-e]

I think it might have to do with the sophistication of the design. This reacts as if it is unregulated so lower input on the transformer should just mean lower output...not more heat. I can issue one dim command and the LED's will dim. If it were regulated I would think that wouldn't be the case. Circuits with a voltage regulator would be trying to compensate for the lower voltage and could overheat.

It'll be an interesting experiment in any case.

[dhoch]

Let us know when it gives up the ghost... I'll bet around 2-4 weeks :)

Dave

[bill-e]

Dave, will do :)

But not withstanding your experience with the Coralife unit which was probably regulated, can you (or someone) explain what is going to overheat and fail in a circuit without a regulator when you reduce the AC input?

[collins]

bill-e, I’m not an electrician, so I hope I have this right….

Transformers are designed so that there is enough primary voltage to overcome the magnetomotive force in opposition to that of the primary circuit when a load is placed on the transformer. If the voltage is reduced, especially in inefficient transformers, you will have a heat build up rather than an inductance to the secondary circuit.

[aiko670]

<a href=showthread.php?s=&postid=9934020#post9934020 target=_blank>Originally posted</a> by collins
bill-e, I’m not an electrician, so I hope I have this right….

Transformers are designed so that there is enough primary voltage to overcome the magnetomotive force in opposition to that of the primary circuit when a load is placed on the transformer. If the voltage is reduced, especially in inefficient transformers, you will have a heat build up rather than an inductance to the secondary circuit.

I'm not an electrician either but that sounds impressive:cool:

[TechniTony]

In VERY simplified terms; The problem is that the dimmer modules "dim" by pulsing the output current using an SCR. The output is actually cycling on/off rapidly. On a traditional incandescant source this does not allow the lamp to a full burn but on a transformed or motor circuit it means that the device is being slammed on and off several times a second thus not allowing it to operate efficiently and it will overheat due to the stress involved. If you use a dimmer source specifically manufactured for an inductive circuit it will decrease the output voltage instead of pulsing and allow the transformer to do its job. However the standard x-10 lamp module is SCR based and thus flashing the output not decreasing the current available. A good example of this is the type of dimmers sold for controlling a ceiling fan will be an inductive where as a regular household dimmer is not. Hope this helps, Tony

[bill-e]

Technitony,

Thanks. Is there a resistive X10 compatible module available? I suppose an alternative would be to pick up a cheap universal transformer and just set it to like 3v to dim the blue LED's a bit and plug it into an appliance module.

[TechniTony]

Under their Pro line and under some other product lines that are X10 compatible they do have inductive capable dimmers, however I have only seen them as a wall switch module so you would likely have to build some enclosure. Look for a low volt track light or fan dimmer module. If you Google X10, you will open up a world of this stuff :) Tony

[bill-e]

Tony, yea, already did the google and couldn't find anything in a plug in module. I'll just buy a $20 inductive wall dimmer and stick it in a Romex dual box with an outlet and a short plug.

[TechniTony]

I can't guarantee how your transformer will handle it, but this is the right dimmer for a transformer. Hope all works out. Tony