Meanwell LDD drivers

[cjrudy]

Get I get the two dimming ports on my current relay box to work with LDD drivers. Their output voltage is 2-52VDC and I think the RA is 0-10VDC.

[lnevo]

The output voltage has nothing to do with the voltage on the dimming signal. You should be just fine controlling the drivers from the RA. I believe you need the analog dimming for those drivers though.

[cjrudy]

The spec sheet for the drivers says built in PWM

[cjrudy]

Also will they work with the dimming expansion ?

[lnevo]

Yea PWM one then...

[rimai]

Looking at the spec sheet, I notice that the PWM signal needs to be 0-5VDC instead of 0-10VDC.
If you want to use this drivers, you will need to mod your relay box.
http://forum.reefangel.com/viewtopic.php?f=2&t=2980
You can also order the dimming expansion module with 0-5VDC signal. Just put it in the notes as special request.

[cjrudy]

So mod the relay box myself or order a dimming expansions module already modded for me. Got it, thanks.

Looking at the sizes of those drivers it just makes more sense to use LDD instead of ELN when building a DIY LED fixture

[rimai]

You need to provide a powerful enough DC voltage.
If you look at the size of the power supply, you will be surprised.

[cjrudy]

I see what you mean, smaller LDD drivers with the additional large power supply or the slightly larger ELN drivers. Looks like either way I'm mounting something remotely so its off the LED Fixture.

Probably not worth the hassle of modding anything.

Although 6 ELN drivers is about $200 and 6 LDD drivers with two additional DC power supplies is only $100

[thekameleon]

Does anyone know if these LDD drivers offer deep diming or basically being able to dim the light output to zero. Instead of the 50 to 100% that the ELN drivers seem to do.

[fatman]

Does anyone know if these LDD drivers offer deep diming or basically being able to dim the light output to zero. Instead of the 50 to 100% that the ELN drivers seem to do.

I haven't tried them, but I have been told by people that do use them that they will go right down to zero so you can dim below the usual 10% cutoff. I should have about 6 channels up this fall using them.

Fat

[cjrudy]

Does anyone know if these LDD drivers offer deep diming or basically being able to dim the light output to zero. Instead of the 50 to 100% that the ELN drivers seem to do.

I haven't tried them, but I have been told by people that do use them that they will go right down to zero so you can dim below the usual 10% cutoff. I should have about 6 channels up this fall using them.

Fat

+1

They go right to zero, the advantage of that is freeing up a at least two ports on my relay box.

[thekameleon]

You say down to zero, so that applies to output as well. With my Meanwell drivers, when I apply 10% the LEDs seem to be at 50% brightness already. So with the LDD at 10% at the input will I have 10% brightness?

[rimai]

That's the human eye perception to light...
You can correct it through math.
http://neuroelec.com/2011/04/led-bright ... ection-no/

[rimai]

Talk to Kraven.
http://forum.reefangel.com/viewtopic.php?p=25582#p25582

[Rodasphoto]

I have ldd drivers on a DIY build I just completed and they do dim to 0. I currently use my near uv and royal blue set around 3 or so as moon lights.

[KRavEN]

Talk to Kraven.
http://forum.reefangel.com/viewtopic.php?p=25582#p25582

Here's code that take 0 to 100 percent and converts to 12bit PWM corrected luminance value. If you're using 8 bit change PwmMax to 255.

Code: Select all

int RA_PWM::getLuminanceValue(byte Percentage) {
  int PwmMax = 4095, Steps = 100;
  int value;
  float Lum, Pwm;
  Lum = ((float) Percentage / (Steps - 1)) * 100.0;

  if (Lum < 8.0) {
    Pwm = Lum / 903.3;
  }
  else {
    Pwm = pow(((Lum + 16) / 116), 3);
  }

  value = (int) round (Pwm * PwmMax);
  return value;
}

[KRavEN]

Talk to Kraven.
http://forum.reefangel.com/viewtopic.php?p=25582#p25582

Here's code that take 0 to 100 percent and converts to 12bit PWM corrected luminance value. If you're using 8 bit change PwmMax to 255.

Code: Select all

int RA_PWM::getLuminanceValue(byte Percentage) {
  int PwmMax = 4095, Steps = 100;
  int value;
  float Lum, Pwm;
  Lum = ((float) Percentage / (Steps - 1)) * 100.0;

  if (Lum < 8.0) {
    Pwm = Lum / 903.3;
  }
  else {
    Pwm = pow(((Lum + 16) / 116), 3);
  }

  value = (int) round (Pwm * PwmMax);
  return value;
}

Actually if you're looping 0 to 100 the Steps should be 101 because 0 is a step. So for 8 bit it would be:
int PwmMax = 255, Steps = 101;

And 12bit:
int PwmMax = 4095, Steps = 101;