Deep Dimming Drivers (dim to zero or off)

[Observe & Report]

If you're designing an LED system, it's handy to have drivers that can shut off when dimmed all the way down. Otherwise you might need relays to turn them off electronically. According to the data sheets, not all drivers can do this. For instance, data sheets for the 3-in1 dimming on MeanWell LPF and HLG drivers indicate that they only go down to 10%

I hooked up Bridgelux Veros to five MeanWell LPF drivers (three 90W with '29s, a 60W, and a 40W each with '18s) and used 100k pots on the dimming wires. Turned them all the way down and was expecting them to go to 10% or maybe even bounce up to 100% once the resistance got low enough. I was pleasantly surprised to find that they turned the LEDs all the way off. Power consumption for all five drivers together when dimmed all the way down was less than 1W. An individual driver didn't register on the KillaWatt. I have no idea what the behavior is when using a voltage source or PWM on the dimming wires. I'm think that the drivers are well designed and there is no risk of leaving them dimmed all the way down for 12 hours or more but I have no special information.


MeanWell LPF 90/60/40 : dims to zero with 100k pots


If you discovered that your drivers that dim all the way down you should post here.

 

[Gaius]

Great way to do some real-time spectrum mixing, and ease your eyes when working on plants. If you are only doing a few drivers this is a great option. Dimmable drivers are significantly more $$$ though, so larger arrays will get pricey.

 

[MrFlux]

MeanWell LPF 90/60/40 : dims to zero with 100k pots

Thanks this is good to know. The dimming is still step-wise, right? As in jumping straight from 10% to 20% etc.

 

[Observe & Report]

yes, ten steps to the dimming but when it gets all the way to the bottom the LED goes out and power consumption goes down to almost nothing. Also, the drivers make a small but audible noise at lower dimming levels from the electronics working hard to maintain a small amount of current but the noise disappears completely when they hit zero.

 

[smokey the cat]

Thanks for the power consumption figures. I love dimming these things - it's really a pleasure to be able to work in the cab with the lights adjusted.

Now that you've seen the same emitter with all 3 drivers - what are your thoughts on it? I have the lpf-60 and my impression that the increase from 70-100% doesn't seem to be all that worthwhile. I am not a plant of course, but I can confirm that the heat really seems to pour out of them at 40W plus.

I'd almost think the 40W driver should be enough grunt to get things moving.

 

[akaki]

If you're designing an LED system, it's handy to have drivers that can shut off when dimmed all the way down. Otherwise you might need relays to turn them off electronically. According to the data sheets, not all drivers can do this. For instance, data sheets for the 3-in1 dimming on MeanWell LPF and HLG drivers indicate that they only go down to 10%

I hooked up Bridgelux Veros to five MeanWell LPF drivers (three 90W with '29s, a 60W, and a 40W each with '18s) and used 100k pots on the dimming wires. Turned them all the way down and was expecting them to go to 10% or maybe even bounce up to 100% once the resistance got low enough. I was pleasantly surprised to find that they turned the LEDs all the way off. Power consumption for all five drivers together when dimmed all the way down was less than 1W. An individual driver didn't register on the KillaWatt. I have no idea what the behavior is when using a voltage source or PWM on the dimming wires. I'm think that the drivers are well designed and there is no risk of leaving them dimmed all the way down for 12 hours or more but I have no special information.


MeanWell LPF 90/60/40 : dims to zero with 100k pots


If you discovered that your drivers that dim all the way down you should post here.

please can you send my the circuit of the meanwell lpf with 100k pot?the 3 pins of the pot disturbing me a bit.
I thought that i have to use 10k resistor before the 100k pot.

 

[VegasWinner]

If you're designing an LED system, it's handy to have drivers that can shut off when dimmed all the way down. Otherwise you might need relays to turn them off electronically. According to the data sheets, not all drivers can do this. For instance, data sheets for the 3-in1 dimming on MeanWell LPF and HLG drivers indicate that they only go down to 10%

I hooked up Bridgelux Veros to five MeanWell LPF drivers (three 90W with '29s, a 60W, and a 40W each with '18s) and used 100k pots on the dimming wires. Turned them all the way down and was expecting them to go to 10% or maybe even bounce up to 100% once the resistance got low enough. I was pleasantly surprised to find that they turned the LEDs all the way off. Power consumption for all five drivers together when dimmed all the way down was less than 1W. An individual driver didn't register on the KillaWatt. I have no idea what the behavior is when using a voltage source or PWM on the dimming wires. I'm think that the drivers are well designed and there is no risk of leaving them dimmed all the way down for 12 hours or more but I have no special information.


MeanWell LPF 90/60/40 : dims to zero with 100k pots


If you discovered that your drivers that dim all the way down you should post here.

right now only European mean well drivers dim to zero. All American Mean well drivers dim to 90% and require a relay to shut on/off. You can use a SSR for 220v systems and a 20/30A relay from sparkfun for turning on/off.

please can you send my the circuit of the meanwell lpf with 100k pot?the 3 pins of the pot disturbing me a bit.
I thought that i have to use 10k resistor before the 100k pot.

For connecting the pot, as you look down on it, the left leg gets the resistor, the middle leg gets connected to DIM-.

 

[CobKits]

right now only European mean well drivers dim to zero. All American Mean well drivers dim to 90% and require a relay to shut on/off.

i have 480s and 320s which both dim to zero via the pot

 

[VegasWinner]

i have 480s and 320s which both dim to zero via the pot

really. kewl to know. so if they dim via pot they will dim via pwm also then. You can use a ICL7667 or a mosfet TIP 120 to dim to zero with no external power source, just using the internal 10v dimming circuit. Only the mosfet has a 5A max current draw. normal operation is using a 2.2k resistor on the gate and get 1A output, so if you use a 1k resistor you can get 2A so at least a C2100B capability over 2A you will have to use them in series to step up another 1000 fold. PWM usually is 250mA so 2.5 A max with no resistor, which I would not recommend, but put a second fed by the first at the gate and you can get at least 10A output for driving the dimming circuit. in Dimming the issue is amps not volts. many transistors can dim, but most cannot handle 2A or more draw and can cause a failure of the arduino/RPI, etc.