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Flex Bits & Blindfolds
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Discussion Starter · #1 ·
Hey guys, I need some input. I run a lot of tape lighting. The stuff I use comes in reels of 16.4 feet, and has a total load of 42 watts. To dim these, I use a magnetic power supply, with a magnetic low-volt dimmer, Lutron LV600P. The LV dimmer needs a load of at least 40 watts to operate properly, if I use a full reel its great. However, when I cut the tape down, to lets say 10 feet, I'm only at ~25 watts, and I anticipate a flicker at low dimming levels. I'm thinking I need to add a load-side resistor to reach the 40 watts. I'd like a set of dimmers that don't require a minimum load.

Have any of you wired a LV Dimmer without having a 40 watt LED load?
Did it flicker?
Did you use a resistor, if so which?

I've haven't set up a circuit like this before, so any help would be beneficial.

Part of me just wants to put a bulb near the power supply, but the customer would have a hell of a hard time remembering where the bulb is in order to change it every time it burns out. A resistor would be best, but I wouldn't begin to know where to get an inline low volt resistor. For the time being I just reordered another ribbon with a higher wattage output.

I've been using Flexfire LEDs the last few years and they're great. Cheap(ish) unparalleled customer service, and a knowledgeable sales staff. The only problem, is I personally think it's a little too white for me. I like my lighting to be 2700k their's is closer to 3000k. There ribbons are 5.12 watts/foot because they have double the LEDs than anybody else. 10' @5.12watts is 51.2, greater than the 40 needed for a dimmer.

In my option, with the stuff I've tried, GMLighting has the best and most consistent color temperature. However, they use half the LEDs as Flexfire, so 2.56 watts/foot is 25.6 watts per 10' and less than the required 40 watts by the dimmer. Which basically means that I can never cut GM if I want to use a dimmer.

I'm using my house as a guinea pig to use resistors, just not sure how yet.

In a perfect world I want to use Flexfire parts, and GMLighting's ribbon
 

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I've been using Flexfire LEDs the last few years and they're great. Cheap(ish) unparalleled customer service, and a knowledgeable sales staff. The only problem, is I personally think it's a little too white for me. I like my lighting to be 2700k their's is closer to 3000k. There ribbons are 5.12 watts/foot because they have double the LEDs than anybody else. 10' @5.12watts is 51.2, greater than the 40 needed for a dimmer.
Then they should be able to supply you a dimmer?

Have a look here...
http://www.leevalley.com/en/wood/page.aspx?cat=1,43349,70322&p=70323

You will see they sell the tape, power supplies, switching, dimmers, etc.

Why re-invent wheel. Buy the system. From your supplier or someone that has the technology to make it work.
 

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Flex Bits & Blindfolds
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Discussion Starter · #3 ·
Then they should be able to supply you a dimmer?

Have a look here...
http://www.leevalley.com/en/wood/page.aspx?cat=1,43349,70322&p=70323

You will see they sell the tape, power supplies, switching, dimmers, etc.
Yes, but these dim the feed out of the power supply with a goofy remote switch. I want to dim the feed into the power supply so that all the switches in the house match.

Why re-invent wheel. Buy the system. From your supplier or someone that has the technology to make it work.
Even after the wheel was invented someone had to put rubber on it.

I like perfect. :whistling2:
Apparently not.
 

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Flex Bits & Blindfolds
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Discussion Starter · #6 ·
Why not install a dimmable driver and dim the line voltage side?
That's exactly what I want to do, but the load is only 25 watts, and less than the required 40 watts for the dimmer. I may try an install a resistor on the load side of the power supply.
Something like this is used for converting turning signals in cars to LED.
http://www.amazon.com/CUTEQUEEN-TRADING-Resistors-Cancellor-Lightswith/dp/B00JIJ99FQ/ref=sr_1_20?s=automotive&ie=UTF8&qid=1398987432&sr=1-20&keywords=load+resistor
 

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You adjust the little black "wheel" knob with the dimmer all the way down until the load does not flicker. I'll try to find a link, but I know for a fact I've dimmed less than 20w of led par lamps with one no problem.
 

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Flex Bits & Blindfolds
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Discussion Starter · #11 · (Edited)
You adjust the little black "wheel" knob with the dimmer all the way down until the load does not flicker. I'll try to find a link, but I know for a fact I've dimmed less than 20w of led par lamps with one no problem.
That's probably true with a standard dimmer, but not a low voltage magnetic dimmer.
Lutron LV600P.
 

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You have to use that specific dimmer? I'm talking about an electronic dimmer to control the voltage on the 120v side of a dimmable LED driver. If you have to use the LV magnetic dimmer, then I suppose increasing the load via resistor may be your only option and I don't really have anything valuable to add.
 

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Flex Bits & Blindfolds
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Discussion Starter · #13 ·
.

You have to use that specific dimmer? I'm talking about an electronic dimmer to control the voltage on the 120v side of a dimmable LED driver. If you have to use the LV magnetic dimmer, then I suppose increasing the load via resistor may be your only option and I don't really have anything valuable to add.
Yeah that one works, but I'm a stubborn cuss that doesn't want 16 matching toggle switches in my house and one odd ball ugly ass oval things. :laughing:
 

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I actually think lutron makes a CL toggle/slide dimmer. Ariata or something like that? Can't remember I'll look and get back to you if I have time.
 

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Lutron Load

Did you include the transformer in your load calculation. UL requires the transformer to be 80% efficient. 25 watts post transformer is roughly 31 watts to the dimmer. If you use Lutron's Maestro dimmer, you could tune the flicker out by trimming the low end up. Lutron won't guarantee it, but it will work. You could test it with a standard dimmer, and if it works, replace that dimmer with the Mag-LV dimmer. You can't leave the standard dimmer as it may damage the transformer, and potentially cause a fire.
 
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