Limiting 0-10v max output on APEX?

A4goulet · Mar 11, 2018

I am looking for a way to limit the max output on the Apex 0-10v V1-V4 outputs or change the 10v default when output switch is in the ON position, Now I already have my program the runs my current DIY LEDs up to certain percentage but my concern is when I turn my output switch in Fusion from off/Auto to ON. When the switch is in the ON position the Apex defaults to 100% (10v).

This concerns me because I am looking to use a Meanwell HLG series drivers on an upcoming build that has a max output of 1050mA to drive LEDs that have a max current rating of 1000mA. I can obviously program the Apex to only ramp up the LEDS 90% but what happens if I accidentally turn the output switch on? I will overdrive my LEDs at 1050mA and risk burning them up. There any programming that will prevent this from happening? My other option is installing a resistor to drop the 10v output voltage before the driver. Does anyone have any experience with resistors on the 0-10v output?

Unlike the meanwell ELN series, HLG drives do not have an internal current adjustment.

Brew12 · Mar 12, 2018

A4goulet said:
I am looking for a way to limit the max output on the Apex 0-10v V1-V4 outputs or change the 10v default when output switch is in the ON position, Now I already have my program the runs my current DIY LEDs up to certain percentage but my concern is when I turn my output switch in Fusion from off/Auto to ON. When the switch is in the ON position the Apex defaults to 100% (10v).

This concerns me because I am looking to use a Meanwell HLG series drivers on an upcoming build that has a max output of 1050mA to drive LEDs that have a max current rating of 1000mA. I can obviously program the Apex to only ramp up the LEDS 90% but what happens if I accidentally turn the output switch on? I will overdrive my LEDs at 1050mA and risk burning them up. There any programming that will prevent this from happening? My other option is installing a resistor to drop the 10v output voltage before the driver. Does anyone have any experience with resistors on the 0-10v output?

Unlike the meanwell ELN series, HLG drives do not have an internal current adjustment.

I wouldn't worry about it. Overdriving LED's by such a small amount will likely have no noticeable impact on their life expectancy. The only way I would worry about it is if I planned on running them at 100% for months on end. Actually, I might not even worry about it if doing that... you are talking an overdrive that is so small that it is within the accuracy range of the driver. The accuracy of the max current of the HLG-120H-C driver is + or - 5%. This gives an actual max current of 1000mA to 11oomA. Overdriving an LED by a maximum of 10% is likely within the design spec of the LED. Even then, most LED's can be overdriven by over 200% for short periods of time with only a slight reduction in life expectancy as long as they have a proper heat sink.

A4goulet · Mar 12, 2018

Brew12 said:
I wouldn't worry about it. Overdriving LED's by such a small amount will likely have no noticeable impact on their life expectancy. The only way I would worry about it is if I planned on running them at 100% for months on end. Actually, I might not even worry about it if doing that... you are talking an overdrive that is so small that it is within the accuracy range of the driver. The accuracy of the max current of the HLG-120H-C driver is + or - 5%. This gives an actual max current of 1000mA to 11oomA. Overdriving an LED by a maximum of 10% is likely within the design spec of the LED. Even then, most LED's can be overdriven by over 200% for short periods of time with only a slight reduction in life expectancy as long as they have a proper heat sink.

Awesome! Thanks Brew12. I appreciate the response and info.

User1 · Mar 12, 2018

Interesting. I assumed (incorrectly I see now) that when you moved from AUTO to ON that it would max at what you have it set for. Not full power. I just tried it and it goes to 100% - learn something new every day. Go figure. Having said that make sure you have proper voltage and cooling and you should be good. I'm also using DIY with Acrostar multi channels with a similar MeanWell power source. Not too concerned about it once I got proper cooling. Even without my fans on running 80 to 100% it was only warm to the touch - the fans just add insurance is the way I see it.