LEDgardener

I've purchased one of the 4 packs of QB120 (3000K) boards from Amazon, and a HLG-185H-24A supply, along withsome connectors. Last night I started rigging things up to make sure things work as expected, and was happily surprised at the ease of putting things together, as well as brightness of the lights.
As recommended by Humple on another thread (viewtopic.php?f=11&t=838), I'm going to use 3 of these boards in parallel, and save the 4th for a spare or cloning.

I have a couple questions about setting this up permanently:

1. Is it reasonable to connect the boards using the molex connectors as shown in the first image? They're wired in parallel, but it means linking the boards as shown. Is there a reason why I should run wires to each board from the supply separately?
2. The wire I have on hand is about 18ga stranded copper. I tinned each end, but they don't fit into the molex well (Actually, they don't stay inserted). Wondering what the best recommendation for wiring is? I have a spool of 14/2 wire (black / white / bare gnd) for house wiring. Could I strip off the outside jacket on this and use the black and white wires separately? Or is that overkill? Am I better to solder something directly onto the V+ and V- test points on the boards?
3. I'm planning on mounting these on a sheet of aluminum to add some heatsinking. Any suggestions on the cheapest place to find something appropriate in Canada? I found a local metal shop that can cut a piece of 12" x 36" x 1/8" for just under $50. That seems pretty pricey to me... Any other alternatives that folks have found?

Thanks in advance for any and all advice!
Peacefrog69

nice I was thinking of doing the same for a mother light!

1) they(hlg) recommend not doing to many boards in parallel like that because of thermal runaway.. 3 boards you should be ok. you just don't want to hook up 4+ in a row to be safe..
https://horticulturelightinggroup.com/p ... rd-guide-1. they show 3 inline but a smaller driver that's why it doesn't work ( amperage) and you can see how they wire 4.

2) I used the wire GM5 recommend... https://www.amazon.com/gp/product/B00IN ... k_id%7D%7D solid core 18AWG. the 14/2 house wire "might" just fit in the connectors.. ( normally use 16/18/20awg) but double check the voltage and amperage the wire can handle.. if it fits and in range then yes your good. and yeah you would strip that outer jacket off at lease near connectors..

3) that's not too horrible, shipping duties etc would have it over that price if ya ordered online... there's always your local thrift/dollar store to check for cookie sheets...I've seen people use cheap aluminum cookie sheets as heat sinks when not using a crap load of watts

also welcome to the forum.. you must of joined while I was m.I.a. for awhile

1. The reason you wire parallel with that driver is it is a constant voltage driver. It supplies each board with the same voltage, and splits the current between each if the boards.

2. The cheapest wire I found for parallel wiring like that was 18/2 solid core thermostat wire. You don't want to go any bigger than 18ga. 14 might fit, but people have a really hard time getting 16ga out.

3. As someone pointed out in your last post, you may not need a heatsink. You could just build an aluminum frame with aluminum angle.

You shouldn’t need sinks for these.

Its better to do home runs for each board because you lose a considerable amount of voltage but chaining through the molecular connectors and it also puts the full current of the circuit through the connectors and trace of the first board in the circuit, which isn’t ideal.

14 gauge will be too big to fit into the molex connectors.

LEDG wrote: ↑

Mon May 07, 2018 5:49 pm

You shouldn’t need sinks for these.

Its better to do home runs for each board because you lose a considerable amount of voltage but chaining through the molecular connectors and it also puts the full current of the circuit through the connectors and trace of the first board in the circuit, which isn’t ideal.

14 gauge will be too big to fit into the molex connectors.

Thanks, LEDG!

I picked up some solid core 18/2 wire at Home Depot last night - thermostat wire - it was $0.99 a metre, so I blew $5, which should be plenty for what I need. Makes sense to wire 'home runs' - i.e. direct runs from the power supply output to the connectors on each board. Not sure whether I should worry about making the runs to each board similar length to make the voltage drop due to resistive losses on each about the same.

Good to know that I don't 'need' a heatsink on this setup, but I think I'll probably buy some aluminum plate anyway, so I can try to drive the boards a bit harder without worrying about them gettting warm/hot. I've seen your videos with the QB288 board, so I suspect I'm probably ok to drive them as hard as possible with the HLG-185H-24A.

Thanks for putting together this great site, and the forums. I've learned a lot, an saved myself from buying cheap Chinese blurple lights! Looking forward to more experimenting as time goes on.

peacfrog69 wrote: ↑

Tue May 08, 2018 11:29 am

Thanks, LEDG!

I picked up some solid core 18/2 wire at Home Depot last night - thermostat wire - it was $0.99 a metre, so I blew $5, which should be plenty for what I need. Makes sense to wire 'home runs' - i.e. direct runs from the power supply output to the connectors on each board. Not sure whether I should worry about making the runs to each board similar length to make the voltage drop due to resistive losses on each about the same.

Good to know that I don't 'need' a heatsink on this setup, but I think I'll probably buy some aluminum plate anyway, so I can try to drive the boards a bit harder without worrying about them gettting warm/hot. I've seen your videos with the QB288 board, so I suspect I'm probably ok to drive them as hard as possible with the HLG-185H-24A.

Thanks for putting together this great site, and the forums. I've learned a lot, an saved myself from buying cheap Chinese blurple lights! Looking forward to more experimenting as time goes on.

Just watch your wiring the thermostat wire I got was only like 150v. As long as it's a parallel build it should work. I'll have to find new wire if I decide to do series at higher voltage.

peacfrog69 wrote: ↑

Mon May 07, 2018 11:50 am

I've purchased one of the 4 packs of QB120 (3000K) boards from Amazon, and a HLG-185H-24A supply, along withsome connectors. Last night I started rigging things up to make sure things work as expected, and was happily surprised at the ease of putting things together, as well as brightness of the lights.

QB120x3-off.jpg
QB120x3-on.jpg

As recommended by Humple on another thread (viewtopic.php?f=11&t=838), I'm going to use 3 of these boards in parallel, and save the 4th for a spare or cloning.

I have a couple questions about setting this up permanently:

1. Is it reasonable to connect the boards using the molex connectors as shown in the first image? They're wired in parallel, but it means linking the boards as shown. Is there a reason why I should run wires to each board from the supply separately?
2. The wire I have on hand is about 18ga stranded copper. I tinned each end, but they don't fit into the molex well (Actually, they don't stay inserted). Wondering what the best recommendation for wiring is? I have a spool of 14/2 wire (black / white / bare gnd) for house wiring. Could I strip off the outside jacket on this and use the black and white wires separately? Or is that overkill? Am I better to solder something directly onto the V+ and V- test points on the boards?
3. I'm planning on mounting these on a sheet of aluminum to add some heatsinking. Any suggestions on the cheapest place to find something appropriate in Canada? I found a local metal shop that can cut a piece of 12" x 36" x 1/8" for just under $50. That seems pretty pricey to me... Any other alternatives that folks have found?

Thanks in advance for any and all advice!
Peacefrog69

Looks good man. I'm considering something similar, using all four boards though. Maybe in configurations of two boards per driver, or all four - for a veg light at the moment.

Having to look/pay for aluminum heatsink material for those, in Can., sounds like it might bring the cost up closer to two QB 288's with Slate 2 heatsink combos. Pretty close anyway. Different applications though.

Nice one.