New build problem

So I finished my cxb3590 build last night. It consists of 2 30" 5.8" profile heatsinks. Each sink has 3 cxb3590s run by a hlg 240h c1750b, so 2 total drivers 1 for each set of 3.
Much to my disappointment when I plugged them in one was much more dim than the other. I have gone through and check all wiring and connections already 10 times. I didn't finish till 3am last night so today I went and bought the $7 harbor freight multimeter. I have tried YouTube but am having a hard time relating info to my build.
I ran the dim driver for maybe 5 minutes no smoke and no cobs blew out. One thing I did notice is the dim driver was much cooler than the bright driver. This leads me to believe it is a driver issue.
I made sure the dim wires were not touching and I never plugged in the drivers without the cobs attached.
I now have the driver removed from the system as I am scared of starting a fire. I was running both drivers off of 1 14 gauge plug.
If some could please walk me through things to check and how to check? I have never used a multimeter before. Much appreciation!

Some pics of the build. You can see how much more dim the light in the front is. The light barely dims when dim leads are touched together as where the other one is a very noticeable distance.Drivers are mounted outside a 3x3 tent. Will use a reefkeeper lite for controlled 0-10v dimming once the whole system is working.

Any help??? Please lol. Would really like some knowledge for when I talk to straightroad tomorrow. Any help would be greatly appreciated.

The Mean Well data sheet specifically forbids shorting the dimmer leads together.

Have you used the DMM? Edit: I don't know how to guide you remotely, sorry.

Oh man I missed that part. They were separated when the issue began. Tried it this afternoon to see if it made any difference as I thought I read somewhere this was a way to dim low. Didn't seem to effect the light that is working properly.
Have never used a multimeter before sorry.

Look up how to measure current (amps) and check to see what the output is. I'm guessing it's not putting out the 1750ma it is supposed to. Good luck working out a return, you will probably have to pay return shipping and wait for another driver. I've never dealt with straight road personally.

Check your thermal interface material proper application? I don't know if a hot running COB will look dim compared to cooler COBs. A hot COB will have lower Vf at the terminals of the COB holder. Is the HGL 240h c 1750b putting out atleast 106 volts with no dimming?

I used the graphite pads from cutter for the thermal interface. All 3 are the same dimness. Kinda hard to think I would get all 3 wrong on one light and all 3 correct on the other.
I have not checked the voltage output of the driver yet as I am unsure how. I will some more googling after work and see if I can figure it out.
I emailed Julia from straightroad and she said she will look into what could cause this. As unhappy as I was with some aspects of straightroad Julia is great at responding promptly.

I hope you get it fixed soon. Dont try silly stuff, take your time to fix it correctly without taking any risks. Often when fixing stuff, people end up destroying their stuff instead of actually fixing it. Please be patient and perhaps call your friend the electrician to use your multimeter.

benbud89 said:

I hope you get it fixed soon. Dont try silly stuff, take your time to fix it correctly without taking any risks. Often when fixing stuff, people end up destroying their stuff instead of actually fixing it. Please be patient and perhaps call your friend the electrician to use your multimeter.

Click to expand...

Yes I am almost 31 years old now and maybe in the past year or two I have finally learned to slow down and stay calm haha. I am just vegging some couple week old plants from seed at the moment. So I have time to get this fixed.
Julia asked me to check current and voltage but am waiting to see if they will offer a walk through on how to do it. I found another thread on here explaining it all but am not willing to blow $150 worth of cobs. Mouser has more in stock so if this issue is not resolved in a week I'll just order a new driver and return this one to straightroad. They seem to think it is wire length causing voltage drop. But this lights wires are the exact same length as the other drivers wires.
We will see what tomorrow brings. Greatly appreciate everyone's help thus far. Even with just one light I saw as much growth in one day as I would in three with my old set up.
Got a shipping notification from thedankteam my packs of LA Plata Alien Blues and Exotic Genetics Gutbuster shipped this morning. So all is well for me at the moment.

Switch drivers to confirm if driver issue or lamp/cob issue. If the dim build works with new driver then driver issue.

High voltage on dc side. Read multimeter basics and manual.
You test driver voltage by setting voltmeter to DC and probe across driver DC side.

Probes across cob for cobs Vf

To test DC current.
or
low end multimeter may have only AC current option and no DC current option.

Edit: this driver supports min 2 and Max 4 cxb3590. Curious why you have 3

Switch one of the drivers out and see if they light up properly. If they do then the driver is the likely culprit, but I would swap it back just to make sure it wasn't a bad connection. If they don't then you could go over all your electrical connections in the DC circuit on the chance there is a weak connection causing resistance. I'm not sure how a faulty cob might play into it, but if not the driver and the connections are good I would start pulling cobs out of the series one at a time to see if one of the cobs is causing the issue.

Man that is why you are a professional lol. Never thought to switch drivers haha! Thanks so much you're the mother fucking man! Thank you

And..........
It's the driver lol. Fuck me hahaha

robincnn said:

Switch drivers to confirm if driver issue or lamp/cob issue. If the dim build works with new driver then driver issue.

High voltage on dc side. Read multimeter basics and manual.
You test driver voltage by setting voltmeter to DC and probe across driver DC side.
View attachment 3614563
Probes across cob for cobs Vf

To test DC current.
View attachment 3614562 orView attachment 3614561
low end multimeter may have only AC current option and no DC current option.

Edit: this driver supports min 2 and Max 4 cxb3590. Curious why you have 3

Click to expand...

I ended up with 3 because I had originally ordered 2100 drivers from straightroad. They showed 2 in stock so I ordered my cobs accordingly. This was on a Friday night. Well @welight was so fast on shipping he had shipped the cobs out before straightroad could let me know their website was showing incorrect inventory. They had 0 of the 2100 and it is a month till they have more. Honestly it has been one blunder after another with Straightroad. I read good things about them here but my experience has been kinda blah. Guess I can't blame a faulty driver on them bit it still sucks haha. Should be interesting to see how they handle this.
BTW too funny you and @Rahz had the exact same idea at the same time pretty much
Smart guys