HLG Driver + Dimmer Stuck on Low/Dim?

Joint Monster

Well-Known Member
Meanwell HLG480-C1750b Driver, with Cased Potentiometer with Knob.

I had it on dim (lowest it goes), went to put it higher and when I turned the knob nothing happened. It just stays dim. (It was working before.)

Does that just mean that Dimmer has gone bad? (Is there any trouble shooting, or cut it and buy and a new dimmer?)
In the mean time, if I cut the dimmer, will the lights just run on full power? (Then I will cut the dimmer leads and cap/hot glue gun off the ends for now as I was going to turn them full anyways.)
 

skoomd

Well-Known Member
Yeah sounds like a bad pot. It happens. Id recommend getting like 20 pots at once (they sell 20 packs of them for about $10 on amazon) and testing each one until you find the best one. Ideally you want a pot that is around 110k ohms of resistence to make sure you're getting the absolute maximum power from your driver. I say this because even the B series meanwell drivers can pump out over their rated maximum. But if your pot is only 100k, you'll only get the rated max.

and yes, you can just remove the pot and the driver will run at mamimum power.
 

Joint Monster

Well-Known Member
Sorry, I'm having trouble finding a potentiometer at a decent price. And I'm super confused, when going to sites like mouser or digikey, they have like hundreds of options!
The only ones I found on Amazon and Ebay were "audio" potentiometer, which I'm guessing is not safe for led?

This is my driver:
https://www.rapidled.com/mean-well-hlg-480h-c1750b/
I would have purchased my potentiometer from there as well, but it's going to cost me $21 for one, if all I order is a single potentiometer.
 

klx

Well-Known Member
For a single driver you just need a 100k pot, they may say they are for audio but do the same thing.

Having said that, the cheap pots are norotious for failing. I have had 2 / 5 fail so I fully expect the rest of my cheap ebay pots to fail eventually. When they do, I will spend the extra money and get some better quality ones.
 

Randomblame

Well-Known Member
Meanwell HLG480-C1750b Driver, with Cased Potentiometer with Knob.

I had it on dim (lowest it goes), went to put it higher and when I turned the knob nothing happened. It just stays dim. (It was working before.)

Does that just mean that Dimmer has gone bad? (Is there any trouble shooting, or cut it and buy and a new dimmer?)
In the mean time, if I cut the dimmer, will the lights just run on full power? (Then I will cut the dimmer leads and cap/hot glue gun off the ends for now as I was going to turn them full anyways.)

Sound like the wrong or bad dimmer or its wiring is wrong. You need a linear 100k potentiometer(better 110k) to use the full potential of the driver and the wiring should look like below. It's a stereo poti but the wiring is the same. You can get them in 5 packs for less than 2$ and with a multimeter you can check it's real resistance. Take the one who is near at 110k to get the most out of your driver.
Screenshot_20180505-121718.png
 

1212ham

Well-Known Member
For a single driver you just need a 100k pot, they may say they are for audio but do the same thing.
Nope, not the same. You want a linear taper pot, audio taper pots are non-linear, logarithmic taper. They will work, but the adjustment gets very sensitive on one end of the range.
 

klx

Well-Known Member

CannaBruh

Well-Known Member
Get alpha or bournes pots and you will find less failures (if any)... the rate of failures with the LED builds is very odd, stop buying cheap shit or solder better?

plastic conductive if you want a nice smooth UX over the range of the wiper

has anyone tried an audio taper? I would expect you might get a worse experience relative to linear but should still work, might have a hard time dialing in any precision.
 

GBAUTO

Well-Known Member
I'd think that the difference is the rate of resistance change vs. knob rotation, The audio taper has a much higher rate of change once it gets near the end of rotation.
 
Top