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View Full Version : Low Volt Dimmer.....Help!!


Go Halogen
11-10-2007, 11:11 PM
Hello All,

Now I know we have discussed low volt dimmers before, but I really need a decent, easy to install, reliable model (and quickly). I finished a job two weeks ago and the client now would like the ability to dim one of my zones.

The fixtures are around some over appreciated artwork that probably cost a pretty penny. They like the effect but want the control option.

I have looked around and can not find anything local?

Please help.......

Thanks in advance!

-Andy

Chris J
11-10-2007, 11:25 PM
Andy,
Sounds like you need some good advice, and you need it now. I suggest you call Gerry De La Vega at Terradek 1-800-609-1130. He is my go-to guy when all else fails. You won't find a more resourseful and knowledgable person about this business. He can answer all of your questions, and give you answers to questions that you didn't ask.

JoeyD
11-11-2007, 12:25 PM
Gerry has access to the dimmers I have used. I dont think he was continuing buinsess with this manufacturer but I think last I spoke about these he had a few of the 10amp versions left.

sprinkler guy
11-11-2007, 12:29 PM
Gerry has access to the dimmers I have used. I dont think he was continuing buinsess with this manufacturer but I think last I spoke about these he had a few of the 10amp versions left.

When I spoke to them last week they only had the 20 amp version available. Still does the same thing, it dims on the low voltage side of the transformer. I just ordered two of them.

NightScenes
11-11-2007, 12:37 PM
The only problem with the 20 amp dimmers is that they are soooo big!! You need a 2 gang box to put them in. I have a couple of the 10 amp dimmers in stock if Gerry is out. I think you might also be able to get them through CLL.

JoeyD
11-11-2007, 12:46 PM
Thats what it was, it was the 20 amp! My bad. Yeah I think you need to run the 20amp in a double gang switch box.

Go Halogen
11-11-2007, 01:20 PM
Thank you all very much for the info. Are these dimmers the ZANE Industry dimmers? They look good but I can not find them? I will call Gerry tomorrow.
In this case....Size does not matter. I can attach inside a gazebo, on the side of a 4x4.

I wonder if I can get two by Thursday????

Thanks Guys.

-Andy

NightScenes
11-11-2007, 02:44 PM
If you call Gerry tomorrow, you should have them in plenty of time.

pete scalia
11-11-2007, 03:15 PM
Hello All,

Now I know we have discussed low volt dimmers before, but I really need a decent, easy to install, reliable model (and quickly). I finished a job two weeks ago and the client now would like the ability to dim one of my zones.

The fixtures are around some over appreciated artwork that probably cost a pretty penny. They like the effect but want the control option.

I have looked around and can not find anything local?

Please help.......

Thanks in advance!

-Andy

I should let you drown instead of throwing you a life preserver based on the way you treat me but here you go even though it goes against my best judgement.

http://www.platinumlightinginc.com/html/12vac.html

irrig8r
11-11-2007, 05:36 PM
I guess I'm either out of the lop or missing something here guys.
I have only used dimmers with incandescent PAR 36 and SCB lamps.

Are you using these with halogen lamps? Are you saying that the halogen cycle when not using the dimmer is enough so as not to shorten the life of the lamps?

If so, what are you telling your customers about how often they can use the dimmer?

NightScenes
11-11-2007, 05:59 PM
When I use dimmers on projects I tell my clients that they need to turn it up to full for 30 minutes, at least once a week. This will allow the tungston to re-attach to the filiment.

Chris J
11-11-2007, 06:56 PM
We went through this a few weeks ago in another thread. I don't beleive the halogen cycle is all that important when it comes to lamp life. Yes, ramping the system up to full power will reattach the tungsten to the filament. But as we discussed earlier, I've seen numerous halogen lamps operating at lower than 10.5v that have been lasting for over 3 years burning an average of 5-6 hours per night. I think the "halogen cycle" thing is just a bunch of hype, but until I have rock solid evidence that it is untrue, I'll be forced as a professional to abide by the rule and educate my customers accordingly.

Go Halogen
11-11-2007, 08:50 PM
Pete.....Please....You are an actual riot. If I were a very religious man I would swear that you are the freakin second coming. Life saver....I think not.
I have several ways to make this work....I only wanted the suggestions of our finer folks here. Stick with your initial judgements from now on. Intuition is everything. We all know that......But hey, thanks for trying.

-Andy

klkanders
11-12-2007, 01:18 AM
Ya I thought all this sounded familiar too!

http://www.lawnsite.com/showthread.php?t=204227&page=2

Looks like others advice was the same as mine....:) Good Luck Andy!

ccfree
11-12-2007, 10:16 PM
Hello All,

Now I know we have discussed low volt dimmers before, but I really need a decent, easy to install, reliable model (and quickly). I finished a job two weeks ago and the client now would like the ability to dim one of my zones.

The fixtures are around some over appreciated artwork that probably cost a pretty penny. They like the effect but want the control option.

I have looked around and can not find anything local?

Please help.......

Thanks in advance!

-Andy

You can buy the Zane dimmers from Ewing Irrigation if you need another source.

irrig8r
11-12-2007, 11:53 PM
Hey Craig. I looked it up on Ewing's website and found pricing, then a search for Zane Interrnational gave me more details.

So if I'm running say five 20W MR 16 downlights, then at 100 W and 11.5 volts that should be about 8.7 A, right?

But if I'm dimming it to say 9.5 volts, then the amperage goes up to to almost 11A right? So just to be on the safe side, I should spring for the 20 A Zane, especially if I ever want more fixtures on the line.

And these are suitable for use in an outdoor box with a standard flip-up switch cover? Or would you recommend the added volume of an "in-use" cover w/o knocking out the holes?

Thanks

ccfree
11-13-2007, 08:52 AM
Gregg, you are exactly right. I will do some investigative work today on these dimmers and get back to you with the whole story. We will see if Zane has taken the amp draw into account. Get back with you tonight. Thanks

sprinkler guy
11-13-2007, 11:38 AM
You can buy the Zane dimmers from Ewing Irrigation if you need another source.

Hey Craig,
Do you have a Ewing part number? I asked my local branch about these, and they didn't know what I was talking about.

irrig8r
11-13-2007, 12:00 PM
You can find it online at Ewing. I don't know if my local branches have 'em. But the part numbers are:

17008100 ZANE 12V/10A 2W AC L/V DIMMER

17008110 ZANE 12V/20A 2W AC L/V DIMMER

irrig8r
11-13-2007, 07:13 PM
I talked with my local Ewing and the guy at Zane International today.

First, Ewing says the 10 A model is more readily available than the 20 A.

UL rating for outdoor installation is still pending, but expected soon, and the guy at Zane said it should be used in a "protected enviroment" whatever that means.

I expect that if I install it at about shoulder height in a box with cover rated for outdoor use I should be OK.

He told me that it doesn't actually lower the voltage, but works by "chopping" the sine wave, like a line voltage dimmer does.

http://home.howstuffworks.com/dimmer-switch2.htm


I think that maybe I'll want to measure the voltage at the fixture to confirm what I get. The product has been out a little over a year.

Interestingly, he said one of their biggest users is Hollywood, for dimming car headlights so they look right on film.

And in case anyone is wondering, the units are built right there in Colorado.

ccfree
11-13-2007, 09:01 PM
ok here is the deal. We recently started carrying these dimmers. We brought them into our central in Phoenix AZ. We don't really know what the demand will be, but we can get them to any part of the country through fedex, and can stock them at your local Ewing of choice if any contractor wants us to. The other part is this for you Gregg. You will lose about 1 volt from the dimmer itself. So you might want to take that into consideration. Now about the amp draw. When a halogen lamp is dimmed, yes the amp current will go up, but what you have to take into consideration is a 50 watt lamp is a 50 watt lamp at 12 volts. If the voltage is reduced, which dims the light intensity, then it is no longer a 50 watt lamp. That is why on a 10 amp dimmer, you can dim 120 watts. So to take it a step farther. A 50 watt lamp pulls 4.16amps at 12 volts. Well the same 50 watt lamp pulls 4.54 amps at 11 volts on paper. In actuality, that 50 watt lamp gets three times the lamp life but output is reduced by 25% at 11 volts. So the lamps is not truly a 50watt lamp at 11 volts.

irrig8r
11-13-2007, 09:57 PM
But Craig, the guy who makes these told me it doesn't truly reduce the voltage, it just "chops the sine wave"...

Which means it just turns on and off faster than we can see it... so does that effectively reduce the voltage too?

Is this where one of those True RMS multimeters comes in handy? This is giving me headache trying to wrap my mind around it now.

INTEGRA Bespoke Lighting
11-13-2007, 10:12 PM
But Craig, the guy who makes these told me it doesn't truly reduce the voltage, it just "chops the sine wave"...

Which means it just turns on and off faster than we can see it... so does that effectively reduce the voltage too?

Is this where one of those True RMS multimeters comes in handy? This is giving me headache trying to wrap my mind around it now.

Dude... time to stop thinking and time to start doing!

Sincerely:
J.S.
Dean, Flying by the seat of your pants university.

irrig8r
11-13-2007, 10:40 PM
LOL. You're right James.

ccfree
11-13-2007, 10:46 PM
But Craig, the guy who makes these told me it doesn't truly reduce the voltage, it just "chops the sine wave"...

Which means it just turns on and off faster than we can see it... so does that effectively reduce the voltage too?

Is this where one of those True RMS multimeters comes in handy? This is giving me headache trying to wrap my mind around it now.

Yes, a True RMS mulitmeter is the way to go. I will hook one up and do the test on a 50 watt lamp and take voltage and amp readings and get back to ya.

sprinkler guy
11-13-2007, 11:27 PM
I talked with my local Ewing and the guy at Zane International today.

First, Ewing says the 10 A model is more readily available than the 20 A.

UL rating for outdoor installation is still pending, but expected soon, and the guy at Zane said it should be used in a "protected enviroment" whatever that means.

I expect that if I install it at about shoulder height in a box with cover rated for outdoor use I should be OK.

He told me that it doesn't actually lower the voltage, but works by "chopping" the sine wave, like a line voltage dimmer does.

http://home.howstuffworks.com/dimmer-switch2.htm


I think that maybe I'll want to measure the voltage at the fixture to confirm what I get. The product has been out a little over a year.

Interestingly, he said one of their biggest users is Hollywood, for dimming car headlights so they look right on film.

And in case anyone is wondering, the units are built right there in Colorado.


Gregg,

I'm impressed you got this guy on the phone. I called him 6 times two weeks ago, over the course of a week. My message was simply "were can I get these?" and he never returned my calls. Thanks to Craig's information, my local Ewing is bringing in some 10 amp units for me tomorrow.

EOL
11-13-2007, 11:56 PM
Hey bro, not to change the subject or anything, but your name sounds familiar and your from Texas. Are you from Pasadena, Tx.?:waving:

irrig8r
11-14-2007, 12:20 AM
Gregg,

I'm impressed you got this guy on the phone. I called him 6 times two weeks ago, over the course of a week. My message was simply "were can I get these?" and he never returned my calls. Thanks to Craig's information, my local Ewing is bringing in some 10 amp units for me tomorrow.

I was surprised he called me back. I left him a detailed voice mail message and he got back to me on my cell in only about a half hour.

Maybe it's just my Sicilian charm. :)

ccfree
11-14-2007, 08:21 AM
Hey bro, not to change the subject or anything, but your name sounds familiar and your from Texas. Are you from Pasadena, Tx.?:waving:

I am actually from Fort Worth TX. But grew up a military brat and lived all over. Been in TX since 1988. Sean, I am glad I could help you find those dimmers.

steveparrott
11-14-2007, 10:58 AM
Craig and others, does anyone know of studies that look at the actual effect of these dimmers on lamp life? I'm thinking that by chopping the sine wave as it does, must present a certain amount of inrush current and thermal shock to the filament.

These are two effects - inrush current due to the fact that a cooler filament has less resistance thus higher current (up to 12X the amps if the filament is cold - it would be less here since the filament will retain much of the heat). Secondly, thermal shock due to sudden expansion and contraction of the filament due to changes in temperature.

My third concern would be filament notching, a known phenomenon when lamps are operated at lower voltages. The filament loses tungsten in an irregular manner (looking like saw teeth) drastically reducing lamp life.

And, of course, there's the halogen cycle, if the bulb wall doesn't maintain a high-enough temp then it will blacken and lamp life reduced.

GE warns that pulsing or flashing circuits may reduce lamp life.

INTEGRA Bespoke Lighting
11-14-2007, 04:23 PM
Craig and others, does anyone know of studies that look at the actual effect of these dimmers on lamp life? I'm thinking that by chopping the sine wave as it does, must present a certain amount of inrush current and thermal shock to the filament.

These are two effects - inrush current due to the fact that a cooler filament has less resistance thus higher current (up to 12X the amps if the filament is cold - it would be less here since the filament will retain much of the heat). Secondly, thermal shock due to sudden expansion and contraction of the filament due to changes in temperature.

My third concern would be filament notching, a known phenomenon when lamps are operated at lower voltages. The filament loses tungsten in an irregular manner (looking like saw teeth) drastically reducing lamp life.

And, of course, there's the halogen cycle, if the bulb wall doesn't maintain a high-enough temp then it will blacken and lamp life reduced.

GE warns that pulsing or flashing circuits may reduce lamp life.

I have extensive field experience in dimming MR16 Halogen lamps powered by both magnetic and electronic transformers controlled by appropriately matched dimmers. (Hundreds of circuits installed in interior applications)

I can honestly say that I have never had any problems with premature lamp failure on dimmed circuits. The only side effect that I have noticed is prolonged lamp life. I am not on site with these system monitoring their usage or their dimming settings, but my clients have reported no problems at all.

In my own home I have dozens of pot lights and track heads that use LV MR16 lamps and all are dimmed. No troubles here either.

It may not be scientific evidence, but in the lab of real life dimming has not been an issue at all.

Eden Lights
11-14-2007, 04:44 PM
Craig and others, does anyone know of studies that look at the actual effect of these dimmers on lamp life? I'm thinking that by chopping the sine wave as it does, must present a certain amount of inrush current and thermal shock to the filament.

These are two effects - inrush current due to the fact that a cooler filament has less resistance thus higher current (up to 12X the amps if the filament is cold - it would be less here since the filament will retain much of the heat). Secondly, thermal shock due to sudden expansion and contraction of the filament due to changes in temperature.

My third concern would be filament notching, a known phenomenon when lamps are operated at lower voltages. The filament loses tungsten in an irregular manner (looking like saw teeth) drastically reducing lamp life.

And, of course, there's the halogen cycle, if the bulb wall doesn't maintain a high-enough temp then it will blacken and lamp life reduced.

GE warns that pulsing or flashing circuits may reduce lamp life.

UhOh! and I told all my clients that could use the panic button on Halloween!!

ccfree
11-15-2007, 10:57 PM
Ok Gregg, although I left my data at the office, I tested the 10 amp dimmer from Zane Industires. This is from memory: put a 50watt lamp on an 8 foot piece of 12-2 with the dimmer exactly in the middle at 4 feet. Starting output was 12.7volts. voltage going into the dimmer was 12.5volts. voltage coming right out of the dimmer was 10.7volts. So it lost 1.8volts just going through the dimmer. To answer your question about the sine wave: The voltage range was 10.7v-.05v. So the voltage does change at the fixture. I took measurements at 5,6,7,8,9,10, and 10.7 volts. Those I left on my desk, but the lower the voltage, the less amperage it had. So I did the math and will get back to you to tell you exactly what the wattage of the 50w lamp was at these different voltages tomorrow. Hope this clarifies some of your questions. Thanks

ccfree
11-15-2007, 11:10 PM
Craig and others, does anyone know of studies that look at the actual effect of these dimmers on lamp life? I'm thinking that by chopping the sine wave as it does, must present a certain amount of inrush current and thermal shock to the filament.

These are two effects - inrush current due to the fact that a cooler filament has less resistance thus higher current (up to 12X the amps if the filament is cold - it would be less here since the filament will retain much of the heat). Secondly, thermal shock due to sudden expansion and contraction of the filament due to changes in temperature.

My third concern would be filament notching, a known phenomenon when lamps are operated at lower voltages. The filament loses tungsten in an irregular manner (looking like saw teeth) drastically reducing lamp life.

And, of course, there's the halogen cycle, if the bulb wall doesn't maintain a high-enough temp then it will blacken and lamp life reduced.

GE warns that pulsing or flashing circuits may reduce lamp life.

Steve, this is what I know about the halogen life cycle. You can dim the lamp all you want, but yes it will blacken and reduce lamp life. You must crank up the voltage around 12 volts for at least 30 minutes at a time once a week, if I remember correctly to revitalize the halogen cycle. Filament notching is more common with vertical filaments. The lamp is actually burned out, but when the fixture is bumped, the filament refuses back together until the system is turned off. So in actuality, the lamp is really burned out. The first two concerns that you had, I would have to research it. I have no idea.
Thanks

irrig8r
11-15-2007, 11:16 PM
I ordered a Zane dimmer from my local Ewing today to try out.