Daddy Tanuki
Solar Wizard
Root cause? hate to be the mean guy in the room, but below is my idea of what the issue is. you can only skimp so much when building something, and 687 USD does not buy a whole lot of anything these days.
Extremely overheated BMS, fused Breaker and dead Inverter. What could be the root cause?
- Thread starter zedconnor
- Start date
I've been running a 6kW MUST inverter for a long time. Mine was $430 back in 2020; but shipping was high because it's a low frequency inverter and weighs close to 50kg. I also run their charge controllers (PC18-10015F, 100A) without issues.
One of the reasons I went with these is because I wanted something I could fix and get spare parts for, and MUST is popular in certain African countries where they don't have a grid to rely on and things need to be able to be fixed. MUST sent me a spare power and control board when I asked for it for my inverter (spare parts, just in case), and the components (for board level repair) are readily available.
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Daddy Tanuki
Solar Wizard
I stand by my statement, you liking or disliking it does not alter the fact that something this cheap is going to have issues. its really that simple.
I don’t care what you have if it got zapped by lightning then the price doesn’t matter. It goes to smoke.
I hope the OP checked his air conditioner to see if it was struck and feedback. Think he has a mini split.
The breaker was recycled most likely several times which is clearly stated until smoke was seen from battery and breaker fuses. Cycling breakers without determining the reason never ends well. Most ppl look for problem longer if have to replace fuse.
I’ve seen these things catch on fire while other ppl swear by them. Lightning is rough on anything if that is what happened. This is one of those things may never know. Blaming the inverter is like blaming the Daly. Where OP is listed for residence it is probably limited. Again seen these things go up in smoke too. Some ppl swear by surge. The old computer surge power strips might protect 1 time but were suppose to be repaired-replaced. The surge devices are not cheap either. They were all over Nuclear plants…. They made nice fire when popped.
I’ve got MPP Solar 3048 and don’t trust it ….cheaper price than that MUST. The way they relabel stuff who knows who made that inverter.
Anything can give problems. Anything.
OP mentioned only lights and 1 hp air con. Might of came in on solar array if has one. May of came in on line if hooked to grid. Again probably never be solved.
My theory on some of the inverter failures is just this….I think some get zapped by battery when turning on and the capacitors have bleed down. With 48v you have a mini lightning strike. Capacitors go bad anyway. Most failures for inverters have noticed it is mosfets and capacitors.
On locomotives we used a hypot machine was labeled hypot to clear high voltage grounds. It had breaker on it. The procedure was flip ac hypot breaker until found the light show, hear the crack, and or seen smoke. The ground showed up quickly. There was a burn feature on hypot but an electrician got severe shock bad procedures so it was disabled. Eventually ac hypot was replaced with megger which was not quick to find hv grounds. The hypot machine was mini lightning… if fed back through sensors then burned them up at 1000-2000 volts. Shhhhssss sometimes the hv grounds came from defective high voltage module sensors….sometimes the ground was high and low getting together. Point is we brought the lightning… the armature of traction motors could only take 500 volts from megger. Everything else could handle 1000-2000 volts except some modules… the flipping circuit breaker with hypot would kill them. We called it destructive testing. It was fast and effective if done properly . Locomotives have float grounds tied to ground relays. I can hardly wait until ground faults pop up on ev as they age.
I hope the OP checked his air conditioner to see if it was struck and feedback. Think he has a mini split.
The breaker was recycled most likely several times which is clearly stated until smoke was seen from battery and breaker fuses. Cycling breakers without determining the reason never ends well. Most ppl look for problem longer if have to replace fuse.
I’ve seen these things catch on fire while other ppl swear by them. Lightning is rough on anything if that is what happened. This is one of those things may never know. Blaming the inverter is like blaming the Daly. Where OP is listed for residence it is probably limited. Again seen these things go up in smoke too. Some ppl swear by surge. The old computer surge power strips might protect 1 time but were suppose to be repaired-replaced. The surge devices are not cheap either. They were all over Nuclear plants…. They made nice fire when popped.
I’ve got MPP Solar 3048 and don’t trust it ….cheaper price than that MUST. The way they relabel stuff who knows who made that inverter.
Anything can give problems. Anything. OP mentioned only lights and 1 hp air con. Might of came in on solar array if has one. May of came in on line if hooked to grid. Again probably never be solved.
My theory on some of the inverter failures is just this….I think some get zapped by battery when turning on and the capacitors have bleed down. With 48v you have a mini lightning strike. Capacitors go bad anyway. Most failures for inverters have noticed it is mosfets and capacitors.
On locomotives we used a hypot machine was labeled hypot to clear high voltage grounds. It had breaker on it. The procedure was flip ac hypot breaker until found the light show, hear the crack, and or seen smoke. The ground showed up quickly. There was a burn feature on hypot but an electrician got severe shock bad procedures so it was disabled. Eventually ac hypot was replaced with megger which was not quick to find hv grounds. The hypot machine was mini lightning… if fed back through sensors then burned them up at 1000-2000 volts. Shhhhssss sometimes the hv grounds came from defective high voltage module sensors….sometimes the ground was high and low getting together. Point is we brought the lightning… the armature of traction motors could only take 500 volts from megger. Everything else could handle 1000-2000 volts except some modules… the flipping circuit breaker with hypot would kill them. We called it destructive testing. It was fast and effective if done properly . Locomotives have float grounds tied to ground relays. I can hardly wait until ground faults pop up on ev as they age.
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Hybrid Solar Inverter & ESS Manufacturer – Must Energy Storage System
www.mustpower.com
Do you know if MUST makes their own inverters or do they relabel?
Who replaced the “ 16Fets?” Were the capacitors blown up? They usually get zapped too.
Any pictures?
Was 1hp Aircon checked out? Split unit?
As far as I know MUST makes their own inverters. But Chinese got alot of oem factories so they may as well be outsourcing too. Nobody knows.Hybrid Solar Inverter & ESS Manufacturer – Must Energy Storage System
Do you know if MUST makes their own inverters or do they relabel?
Who replaced the “ 16Fets?” Were the capacitors blown up? They usually get zapped too.
Any pictures?
Was 1hp Aircon checked out? Split unit?
The FETS are replaced by a local repair shop.
The aircon and everything else on the load side is fine.
I put a new BMS and repacked the cell. The customer is using it without any problems so far.
Same setup same battery and inverter. I replaced the breaker with a Suntree brand.
Ps there is no solar installed.
Inverter is a hybrid inverter so it works with grid at the moment.
