I did some searching through the exisiting threads, and didn't really see an answer to the problem I have.

I have 2 runs of halogen track lights that are controlled by standard X-10 lamp modules, one plug-in, one wall switch. When the lights are off the transformers give off a slight but effectively annoying buzz. They also buzz when dimmed, but I really don't use the dimmer for these lights, just switch them on and off. I swapped the plug-in lamp module with an appliance module, and it stopped the buzzing, but it has the loud relay click, and doesn't respond to all-lights-on/off commands, a must!

So the question is, is there a plug-in module that does respond to all-lights-on/off, has a silent relay that kills the current like an appliance module (or otherwise stops the buzzing)? As a bonus it would be dimmable.

I think what you need it this
part number 2205ACWI
[Link: smarthome.com]

If you try the 2205ACWI and it hums, I recommend instead, our part number 2206WI
[Link: smarthome.com]

Different type dimmer

Home Pro is a new name, sure looks like a XPDI3 same specs? The other is an XPS3 made for Leviton by X10.

Bill
www.homeautomationnet.com

The X10Pro (XPS3 and XPDI3) are just as good, if not better, and are cheaper on Bill's site on this page: [Link: homeautomationnet.com] I'm not sure that's what Kevin is asking for, though.

Kevin,

If the halogens buzz with an appliance module then they will likely buzz with any dimable module. That leaves you with a non-simable module and there really isn't much available at similar cost that doesn't "Thunk" when activated. PCS (http://www.pcslighting.com/) makes a MultiModule that controls non-dimable loads (no buzz) and operates silently but it's price is a lot higher. I think it will also allow you to program whether or not it responds to the all-lights-on command but you'd want to verify that.

Thanks for the tip on the X10Pro XPS3, Larry. That should solve half my issue.

However, one of the halogen strips is simply plugged into a outlet via a lamp module, and I really don't want to go to the trouble of wiring it for a wall switch.

Here's the question again, with emphasis in caps:

So the question is, is there a PLUG-IN module that does respond to all-lights-on/off, has a silent relay that kills the current like an appliance module (or otherwise stops the buzzing)? As a bonus it would be dimmable.

An acceptable alternative would be a wall receptacle rather than a plug-in module.

I've done a fair bit of research, and I'm pretty sure that there isn't something like this, but I'm hoping maybe I've just missed it.

Kevin

Like I said, the PCS MultiModule might do what you want but it isn't in the $20 price range of the others.

Thanks, not sure how I missed that Larry. Looks like it would work, but it is also way more than I need on that wall. I'd have 3 of the sockets going unused!

Kevin, Bill at HomeAutomationNet was kind enough to send me this:

[Link: geocities.com]

You may find it helpful to modify a module for silent operation.

Larry
www.fineelectricco.com

Ooo, now things are getting more interesting. I happened to notice this morning that only one of the 2 halogen strips actually buzzes when it is off, the one connected to the wall switch. As an experiment I grabbed an extra plug-in module, and voila! No more buzzing when it is off. But now it buzzes a bit when it is turned on, and buzzes like crazy if it is dimmed. The module in question is a Radio Shack version. I didn't check the module that works OK, but odds are that it is an X10 Pro module. I'll confirm this and post when I have definite results.

Kev

Kevin, usually it's the filament within the bulb that is "singing", or vibrating, due to the chopped waveform of the A.C. current when dimmed. The filament shakes because of the rapid current changes, which causes contractions. A dimmer knob actually varies a timing circuit, not a voltage level.

When a triac (a special type of power transistor made for A.C.) is used for dimming, the light output is reduced by delaying the turn-on point along the waveform, each half cycle, after which the triac conducts fully for the remainder of the half cycle. This happens twice per cycle, or 120 times a second.

What happens is that the filament sees nearly full voltage, only for less than the full time, so the average power (power over time) consumption is reduced. The filament averages out the overall power, and glows at less than full brilliance, thus dimmed.

This same process is used in model railroading (and other motor controlling) by what is often called "pulse modulation" to allow a train to start from a standstill at a more realistic slow rate of acceleration.

Actually, the difference between dimming an A.C. load and a D.C. load is that, with A.C., the waveform, once the triac is triggered, is still shaped like the sinewave, but with D.C., the waveforem looks like a squarewave, with the width of the wave at full voltage varying with the control.

Instead of varying the voltage level, the ratio of on time to off time (called the duty cycle) is varied, but using full voltage while on. This allows the train motor to overcome friction and inertia without the sudden jerk to a high scale speed.

Hope this was understandable.

Larry
www.fineelectricco.com

Kevin,

I've been struggling with Emerald halogen track lights for a couple months, and finally bought a SwitchLinc 2384 switch. The 600W switch has solved all my problems. Responds to ALL ON/OFF and has multiple dimming capabilities. I am very pleased. I am also thankful to all the folks who provided input to my questions.

Rob