On Tuesday, August 1, 2017 at 11:41:50 AM UTC-4, wrote:
On Sat, 29 Jul 2017 13:22:30 -0700, Jeff Liebermann
wrote:

On Sat, 29 Jul 2017 12:10:34 -0700, wrote:

My son has this lamp: Larson Electronics
epl-hb-150led. It is a 150 watt high bay type lamp. It has six LED
modules and each module is driven by its own driver board.

Is the lamp one of these? The numbers are similar, but there are
additional suffix letters that you did not provide:
http://www.larsonelectronics.com/p-70368-class-1-division-1-explosion-proof-150-watt-high-bay-led-light-fixture-paint-spray-booth-approved.aspx
http://www.larsonelectronics.com/p-144814-ceiling-mount-explosion-proof-150w-high-bay-led-light-fixture-17500-lumens-140-beam-spread.aspx

Only $2,200 each:
https://www.grainger.com/product/LARSON-ELECTRONICS-LLC-Explosion-Proof-Lighting-20LN23

I don't see six LED modules, although with 12 LED's, I can how 6
modules might work and fit:
https://www.google.com/search?q=Larson+Electronics+epl-hb-150led&tbm=isch
No disassembly photos. Bummer.

Could you double check the model number?

If you only have one out of 6 modules currently functional, my
guess(tm) is that you're doing something wrong in the operation of the
light. It might be getting too hot, insufficient ventilation, or too
much applied AC voltage. Difficult to tell from here. If you repair
one or more modules by replacing blown parts with identical parts, I
would give it 5 chances out of 6 of blowing up again.

What I do in situations like this is first make a schematic. Identify
as many parts as possible. For parts obscured with epoxy, use some
type of epoxy softener to ID the part:
https://www.dynaloy.com/products/epoxy
With the one remaining working module, use an oscilloscope to measure
waveforms and voltages. Be sure to isolate the light with an AC line
isolation transformer to prevent the oscilloscope case from being at
AC line potential. Or, use a dual trace scope in differential input
mode. After you repair a module, compare voltages and waveforms.
Thanks for the reply Jeff. I forwarded your message a few minutes ago
to me son and I'll let you know what success or lack of same he has.
I'm gonna get some epoxy softener. I didn't even know the stuff was
made. I should have too because I use epoxy for lots of fixes.
Eric

Wow Eric, if those things are ~$1k+ each I would contact Larson and
talk to some tech guy there. Often when something blows it will take out
several parts... you probably know that.

George H.