Help with Dimming circuit for Meanwell driver

[biglurr54]

I have a DIY led set up to provide actinic to compliment my Halide. I also have another set up to provide let for an algae scrubber. Both of these systems run off of Mean Well ELN-60-48D Drivers. I have a driver for each led set up. I do dim each led fixture on occasion for acclimating corals and to promote more algae growth on the scrubber. I currently am using a 7.5 volt power supply for the dimming channels. I tuned each driver to put out 700ma max when the dimmers are turned all the way up.



My question is would it be beneficial to switch out the 7.5 volt power supply with a 10v power supply and then re-tune the drivers to 700ma at full power? What will I gain? Will it provide for smoother dimming, or more degrees of dimming? Will it not make a difference at all and just be a lot of extra work for little or no gain?



Thanks for your help!



Sent from my SM-N910V using Tapatalk

 

[mcgyvr]

I don't believe you can get a ELN-60-48D down to 700mA..
I thought it was 1.3A -25%/+3%
So I think you can only get slightly under 1000mA (1A)

Just leave it as is..

 

[biglurr54]

Using the internal pot, you can dial it down.

Sent from my SM-N910V using Tapatalk

 

[biglurr54]

It can do 0 to 1.3a via internal pot adjustments.

Sent from my SM-N910V using Tapatalk

 

[mcgyvr]

It can do 0 to 1.3a via internal pot adjustments.

Sent from my SM-N910V using Tapatalk

Not according to the datasheet..
Its factory set at 1.3A and allows -25% to +3% max via internal SVR2 potentiometer..
So roughly 1A (-25%) to 1.4A (+3%).

 

[oreo57]

Not according to the datasheet..
Its factory set at 1.3A and allows -25% to +3% max via internal SVR2 potentiometer..
So roughly 1A (-25%) to 1.4A (+3%).

Right MAX current adjustment..
not convinced the driver changes current as opposed to changing the average current at max levell
Like 1.2A @ 50% duty averages .6A.....
Need an oscilloscope trace of the output..

Anyways some reference..
http://www.adminstrumentengineering.com.au/sites/default/files/mean-well-led-technical-manual.pdf

 

[nbinc]

Watch this - Adjusting the ELN 60 48D
https://www.youtube.com/watch?v=k1thXysaHtY

 

[aaron7405]

I don't believe you can get a ELN-60-48D down to 700mA..
I thought it was 1.3A -25%/+3%
So I think you can only get slightly under 1000mA (1A)

Just leave it as is..

If I am not wrong there is a screw inside the ballast so you can dial it. tha way you can run the lower amp leds.

 

[TheFishGuy31]

Not according to the datasheet..
Its factory set at 1.3A and allows -25% to +3% max via internal SVR2 potentiometer..
So roughly 1A (-25%) to 1.4A (+3%).

Absolutely right. I have a few of those laying around & they will not dim to 0 using the internal pot.

You can turn the internal pot down, but at 10v input on the DIM the lowest the driver will output is 1.0A.

9v=.9A, 8v=.8A, ect.

I think the way you're doing it right now is the best way to use those if you only want to have a 700mA output.

 

[oreo57]

http://www.bridgelux.com/sites/default/files/resource_media/BRIDGELUX-SSLS-ENG-LTR-v09-SCREEN.pdf

I think the way you're doing it right now is the best way to use those if you only want to have a 700mA output.

Ok let me try this again, and hopefully someone can actually prove me wrong or right..

you will NEVER have 700mA constant current..
even regardless of what a VOM may say.. since they are only usually averaging over time..
What you do get is 1A @70% of the time..

AND regardless of how the DIM circuit gets its signal.. That doesn't mean anything to the drive circuit really..

NOW I do realize I could be in error ..but I do believe I am not. That Bridgelux paper I
linked to lists recommended drivers.

Dimming
Bridgelux recommends dimming LED Arrays using
pulse width modulation (PWM). Pulse width
modulation is illustrated in Figure 5. Using PWM methods for dimming will result in consistent performance between multiple LED Arrays in a lighting system or installation at reduced light output levels, ensuring luminaire to luminaire consistency over a wide range of output levels.

Just keep in mind "signal" is not always the same as output.
I believe Bridgelux would not recommend any ELN drivers if it "cut" current rather than "pulsed" current.

Again I could be wrong, but don't think so at this point in time.

 

[TheFishGuy31]

AFAIK the ELN drivers use an analog DIM instead of PWM. I'll have to look up what their output is.


Sent from my iPhone using Tapatalk

 

[oreo57]

AFAIK the ELN drivers use an analog DIM instead of PWM. I'll have to look up what their output is.


Sent from my iPhone using Tapatalk

Understood and good luck finding a trace..
That said an unrelated one:

Why even bring up the LDD??
Read the pdf.. Where they use the same (inaccurate) language to describe the current..
http://www.meanwell.com/mw_search/ldd-h/LDD-H-SPEC.PDF
I(out) 0-100% when there is NO absolute change in current.. only pulsing max current for a "over time" average..
And as I stated... signal type may or may not be related to output type..

 

[oreo57]

as an example and IF I understand this correctly on a quick review:
https://www.google.com/patents/US20090184662

In operation, the dimming signal generator circuit 24 receives an input dimming signal and outputs a waveform of a specified frequency where the duty cycle of the output waveform is proportional to the level of dimming. With regard to the variable duty cycle input signals (e.g., the AC phase cut signal or the PWM dimming signal), the generation of the dimming signal involves generating an output signal having a duty cycle that is proportional to the duty cycle of the input signal. With regard to the 0-10V dimming, generation of the dimming signal involves generating an output signal having a duty cycle that is proportional to the voltage level of the 0-10V dimming signal.

 

[Dactylopterus]

Using the internal pot, you can dial it down.

Yes you can change the current from 0 to 1.3. That's why it is a "dimmable" driver.
Changing the maximun dimming signal from 7.5 to 10V will not change much in my opinion.