LEDgardener

Howdy!

New member here! I'm going to be around a while to learn and share!

I currently have a DIY grow light I built which currently employs two MeanWell Drivers.
The ELG-240-C2100A & ELG150-C1050A. Each driver runs its own series of 3 COBs, and are dimmable.
Total wattage: 345
Heatsink for 6 chips: 200mm*200mm*66mm with active cooling utilizing a low profile 7-inch fan, adjustable to up to 240 cfm (according to its specs).


I'm trying to find a way to build another one for a friend who's asked if I can make it for him (here's the kicker) for less.

I suppose challenge accepted, and I'm now considering utilizing a 'constant power' driver as one option to reduce the cost.

The constant power driver I am considering is the ELGC-300-M-A with two CXM-32-40-80-54-AC30-F4-3 in series.
Link to the Driver Specs: https://www.trcelectronics.com/ecomm/pdf/ELGC300.PDF
Link to COB Specs: https://www.mouser.com/datasheet/2/245/ ... 488935.pdf
I'm a little apprehensive as I have only used CC drivers.

Page two of the Driver specs states the constant current region is 56-116v with full power current range 2600-4000mA.
Each cob is rated between 48v-56v & 2200mA-4400mA.

To place these in a series would be mostly safe, I feel, based on the Driver not being able to push more current than the chip is rated to handle. My concern is that tiny difference of the 4v the driver can push into the COBs beyond their max rating..

My understanding is the ELGC-300-M-A should allow me to bring the power down to some degree.

Is my paranoia unwarranted or is that 4v something I should be worried about, being this is a constant power Driver?

What are your thoughts on this?

Thanks for you time guys!

I wouldn't worry about the voltage. ALL led drivers will adjust their voltage output to match what the LEDs want, that's their job, CC, CV, or CP doesn't matter.

It gets trickier to figure out what a CP driver will do because it has a range of both voltages and currents that it can change to hit that power level. My guess is that it will settle around 2.9A and 104V.

Shimbob wrote: ↑

Mon Dec 16, 2019 10:48 pm

I wouldn't worry about the voltage. ALL led drivers will adjust their voltage output to match what the LEDs want, that's their job, CC, CV, or CP doesn't matter.

It gets trickier to figure out what a CP driver will do because it has a range of both voltages and currents that it can change to hit that power level. My guess is that it will settle around 2.9A and 104V.

If it sits at 2.9A @ 104V I’m perfectly fine with that. I know little about the behavior of constant power drivers.

*shrug* I guess there’s one way to find out.

Thanks for the feedback Shimbob

StilLearning101wtf wrote: ↑

Tue Dec 17, 2019 5:58 am

*shrug* I guess there’s one way to find out.

Turn down Io before plugging it in. Got a voltmeter?

I'll boot it up lowest power and take readings of both voltage and amperage as I increase the output. I'll track how it behaves and will share.

I've got a few gadgets here. Volt meters, DIY spectrometer which works surprisingly well. I'm going to get a PAR reader this month to see just how much light it puts out vs whats on paper. On paper it's 60,000 lumen; best I can do until I get the PAR reader.

Going to order the drivers and more cobs today. Will report back.