The mystery of the Mean Well type AB driver models?

[TEKNIK]

Once a voltage is set then leds can not absorb more current from the driver than what the maximum watts of the combination of the volts and amps are, this prevents overload.
I will give an example, if you have a 36V COB set up with 6 COBs in parallel that when connected to your system takes an actual voltage of 34V you can adjust your voltage on the driver down to 34V,
If one COB fails this will not force extra current into the other 5 COBs as the driver will not allow any more voltage to pass.

[Blussum]

Once a voltage is set then leds can not absorb more current from the driver than what the maximum watts of the combination of the volts and amps are, this prevents overload.
I will give an example, if you have a 36V COB set up with 6 COBs in parallel that when connected to your system takes an actual voltage of 34V you can adjust your voltage on the driver down to 34V,
If one COB fails this will not force extra current into the other 5 COBs as the driver will not allow any more voltage to pass.

Yeah that's one of the good sides of the constant voltage drivers with parallel wiring, the current doesn't change in one board/light no matter how many other boards/lights disconnect or malfunction somehow in the system. Actually learned this from LEDGardener's videos, just didn't understand what you meant

[JayKell]

Talked to meanwell a few days ago to verify my hlg-150h-48b drivers were actually type ab. They have a small extra sticker with "code# hlg-150h-48abhl" above the meanwell logo of the main sticker, and dim wires as well as pot adjustments on the body. I was told that the a, b, and ab drivers were all the same boards, available on all drivers, and if it had both dimming leads and knobs, it was an "ab" type. He also said the pots were there on a "b" type, just buried under the potting epoxy (and no holes in the case) for the better ingress protection rating.

As a side note, I found some vague reference on their site before this about the "hl" on my drive possibly being some odd certification, and it may be, but I bought them as new surplus and was told that company initials are often added to the end of a sticker, and they are often preset at the factory, "so be careful". Not sure what he meant by that last bit, probably just warning me to tune it?

[TEKNIK]

They usually make one type of pcb and then change it according to needs of customers, I have seen drivers being made, the seal types of meanwells are tuned before being potted to the voltage output and current. At the driver factory I was at the driver was exactly the same for 12 and 24V they would adjust a screw to set the voltage before they potted the product. Because when the driver is made it is set at 24V to begin with it made the 24V drivers 2 cents cheaper because it saved them time.
Most components that go into drivers are really cheap, it's the time involved in the assembly and testing that adds to costs, they make things cheaper with automated robots as there is still a lot of manual work that is done producing a driver. I would imagine that meanwell has an insane automated system to reduce as much labour as possible now days

[JayKell]

Yup. I just think the rep meant to check the voltage and current first.

[Complex]

The current adjustment screw terminal on the driver overrides the POT. Once current is set by the screw you can dim them as per normal.

The way I would use these in a parallel build is to set the maximum voltage to the output of your boards. This way if a board fails or something goes wrong it will voltage out the rest of the boards so they could not take anymore current.
It is a good fail safe that would work perfectly.

OK, so I'm really wanting to get clarification on this, because LEDG says in his video that you cannot protect against thermal runaway in this manner with more than one board on a driver.
I bought CV A-type drivers only because I thought I could limit parameters and rule out possibility but apparently I misheard something at the time I first hear that you could avoid the risk by limiting the voltage to (just below I thought he'd said) what the voltage requirements were.

[Complex]

Once a voltage is set then leds can not absorb more current from the driver than what the maximum watts of the combination of the volts and amps are, this prevents overload.
I will give an example, if you have a 36V COB set up with 6 COBs in parallel that when connected to your system takes an actual voltage of 34V you can adjust your voltage on the driver down to 34V,
If one COB fails this will not force extra current into the other 5 COBs as the driver will not allow any more voltage to pass.

Yeah that's one of the good sides of the constant voltage drivers with parallel wiring, the current doesn't change in one board/light no matter how many other boards/lights disconnect or malfunction somehow in the system. Actually learned this from LEDGardener's videos, just didn't understand what you meant

So did I, then while re-watching several of his videos I heard him say that this does not work for multiple boards on a single driver... And I was shocked, that I hadn't heard that until now and I didn't/don't quite understand it. Only reason I got CV was because I thought I could do that. Hah, shit.

@LEDG ?

[TEKNIK]

So did you set it up correctly and try it?

[Blussum]

The current adjustment screw terminal on the driver overrides the POT. Once current is set by the screw you can dim them as per normal.

The way I would use these in a parallel build is to set the maximum voltage to the output of your boards. This way if a board fails or something goes wrong it will voltage out the rest of the boards so they could not take anymore current.
It is a good fail safe that would work perfectly.

OK, so I'm really wanting to get clarification on this, because LEDG says in his video that you cannot protect against thermal runaway in this manner with more than one board on a driver.
I bought CV A-type drivers only because I thought I could limit parameters and rule out possibility but apparently I misheard something at the time I first hear that you could avoid the risk by limiting the voltage to (just below I thought he'd said) what the voltage requirements were.

Yeah that's one of the good sides of the constant voltage drivers with parallel wiring, the current doesn't change in one board/light no matter how many other boards/lights disconnect or malfunction somehow in the system. Actually learned this from LEDGardener's videos, just didn't understand what you meant

So did I, then while re-watching several of his videos I heard him say that this does not work for multiple boards on a single driver... And I was shocked, that I hadn't heard that until now and I didn't/don't quite understand it. Only reason I got CV was because I thought I could do that. Hah, shit.

@LEDG ?

LEDG did some crazy experiments with the drivers and had really hard time breaking the quantum boards even with a big driver/power supply and putting out crazy amount of power, go check those videos out.

So thermal runaway is like a myth in that way UNLESS you play with big powers and have a bunch of boards attached to one big driver, having your stuff running on bigger voltages than needed and keep them hot. Personally i've never heard anyone actually break up their system like that, so worrying about a some LEDs going out isn't gonna do anything to the rest of the system. Those Samsung LEDs are actually so damn durable that you can sleep tight without any worries in the world. The only thing that comes to mind must be someone messing up the production intentionally really bad, so the LEDs wouldn't even turn on or go out instantly when you turn on the power (like messed up wiring or something similar).

If after all that you're concerned about thermal runaway, there's always ways to protect against that: You can use a fuse for each board or something like a thermal cutoff switch. I wouldn't bother if you are just an average grower with your average setup with a couple boards per driver. You could always tune down the voltage a little bit and you will be much better off, also keeping the drivers separate from the boards isn't a bad idea to avoid extra heat. Having a fan blowing air in the boards and having a cool fresh airflow overall is enough to keep the boards nice and cool, without any airflow in a closed room things don't only get hot fast for the boards, but also hurt your plants so it's pretty obvious that your airflow game is important for both the lights and the plants

So did you set it up correctly and try it?

I've been running my 4 quantum boards setup for over a year now in my tent without any problem in the world. I ordered two "Kingbrite 240w Quantum Board LM301B V2" kits pretty soon after i found about the quantum boards and did a lot of research before, including this post when i started my journey to the LED world I paid $115 for each kit with separate boards, both have HLG-240H-48AB drivers that i tuned with a multimeter to 5.4A & 48V giving me 260 watts of pure power, if i remember correctly it draws something like 50 watts more from the wall when it's turned up (if i can trust a cheap wall meter, it's useless anyway when tuning a driver).

And on top of that if i remember correctly, i tested the driver voltage range with a multimeter from 0 to 100%, it was something like 43V-53V, so i could potentially draw about 290 true watts from one 240H-48AB driver. That's pretty nuts. But i didn't wanna break my boards so i only run them at max 48V like recommended. And i don't run my boards 100% all grow anyway, i'm just turning them up during the veg and max them out in the flower.

Still trying to figure out how close from the tops of the plant they can be (min/maxing the grow without burning them up), don't wanna ruin my grow so i play it safer than my friend did who drops his ~240w board like 1 feet or even lower from the tops, well he managed to burn some leaves/flower but his quantum board (he has a B driver, so if i remember right it's tuned up to 240w in the factory) is so close that he's playing with fire Well each to their own, on the internet most people and sites talk about keeping your LEDs like 18+ inches away, which is honestly too far unless you got some really powerful lights. Still hunting that sweet spot with my setup, everyone has different system and power so it can vary a lot of course. And more importantly need to also keep the heat and humidity in check, VPD is a thing that affects the grow and plant health so i'm fine tuning that during the grow to get the best results.

Really i would recommend the AB drivers if you wanna tune up your drivers to your liking (need a multimeter to tune it tho), A and AB models really go up to 5.4 Amperes even tho the Mean Well datasheet says their 240H-48 drivers go between 2.5A - 5A. B version is "the safest option" for novices who just want to plug'n'play without needing to touch anything but the pot. And the voltage range seems to be higher too (might also depend on the individual driver, can't confirm either), but being middle of a grow i don't wanna go play with my lights just to check it out, at least no need to check for me anyway.

Better to run the boards with less power so the LEDs last longer too. And you wanna keep them cool too with good airflow, of course they produce more heat when you turn up the power. So having a properly sized inline fan bringing up fresh air every minute and getting that negative pressure in the growing room on top of a fan (or fans) moving air in the room is pretty important tip for new indoor growers I have one one fan blowing above the boards cooling them down and a second one blowing air between & around the the plants so there's no hot spots and the stems strengthen up when they move around too. Keep that air moving and keep it fresh!

I'm also planning to buy some deep red LEDs (maybe a couple strips) to get fatter flowers, i've seen they really make a difference in the flowering cycle. Of course you could go even deeper in the rabbit hole with CO2 and stuff but i'm not gonna go there. Maybe hydroponics would provide faster growth for the plants too if you have enough money, space and knowledge to make that happen. But so far i'm going to keep it simple with only organic stuff, quality soil and keep studying.

[Subhuman]

Hi all. New here. I’ve read all this post but still not understanding the a/b part. I have a 320h 48 a/b geek light with qbs I had them put Cree reds in and some uv. I had them put rocker switches on cables to be able to turn the uv or ir from outside of tent. What I’m not understanding is how the B side works. Say I turn main lights down to 5% and flick one of the switches on it seems to be full power. Either ir or uv. When I turn main light up those don’t get any brighter. Just stays the same. When I had them build this for me about 2 years ago I told them I needed the ir to be able to stay on after lights off but that didn’t happen. Figured I could get a timed schedule dc switch to leave reds on a few after main light went off. So stuck with this. Those Lights are built into boards so can’t run a sep driver I don’t think. There are 4 Wires jumping to each board. So could sombody please explain how this works! Thanks.