Any Electronics Nerds or Gurus on OSA?

[Forgalspop]

I have a 3,000 watt modified sine inverter that quit working and is showing an error code. I had this for our small solar system for a travel trailer I have in place in New Mexico. I have checked all the fuses (8- forty amp fuses) and none are blown. I can see no sign of anything getting hot or damaged.

This inverter was working fine and had very little use and was never over-loaded as far as electrical draw.

The only thing I can think of causing it to fail is that it is rated for a maximum charge current of 15 volts DC and does not have over-voltage protection. The charge controller typically never goes over 14.8 volts in equalization mode. On my phone I have an app that communicates with the charge controller via Bluetooth and it showed the charge controller briefly went over 15 volts the previous day before the inverter failed. (15.2 volts)

When I purchased the inverter I did not realize it did not have over-voltage protection.

In the travel trailer I have a small 750 watt inverter that is well over 15 years old wired on a separate circuit tied to the battery bank and when I turn on the 3,000 watt inverter after it failed, the 750 watt inverter trips for low voltage. This tells me the 3,000 watt inverter is drawing a great deal of juice from the battery bank even though it is not working.

The 3,000 watt inverter has two circuit boards (a primary and secondary board) neither show any sign of anything being damaged. Both have multiple rows of Mosfets. I am guessing there is a failed Mosfet, transistor or capacitor. The key word is guessing! I have no idea.

The company that sells these inverters show replacement primary and secondary circuit boards, but are no longer in stock.

I have since purchased a Samlex brand inverter I have yet to install, that has over-voltage protection and shuts down if voltage goes over 16 volts DC.

I am thinking if the failed inverter could be repaired, I would keep as a backup.

So I was wondering if there is an electronics guru or nerd on OSA that would be interested in taking a look at this inverter. If it can’t be repaired, it will probably end up at the bottom of the lake where I lost all my guns in the boating accident!

Electronics and their repair are above my pay grade!

Thanks!

 

[Dr_Mitch]

There will be a failed (internally shorted) electrolytic capacitor, or one of the MOSFETs, dumping current to ground causing the error. If you have an error code, the will be some kind of reference material in existence that will interpret the error code, however that may reside only with the OEM as trade secret in order to protect IP, which is extremely common for electronics even if purely a cultural holdover for circuits that now exist en masse from all producers. I would call the OEM and ask what the error code means and if it tracks to one of the two boards you reference.

If OEM can’t help, and you don’t see clear evidence of a component or circuit trace that “let the smoke out”, look at the capacitors that are shaped like cans for swelling on the top surface or oil leakage around the bottom. The caps that turn half waves into ripple current are where I would start. If the caps look fine, they might be fine and it’s more likely a MOSFET, but the reality is that >99% of electronics failures not caused by human malfeasance or natural disaster since electronic circuits were invented in the early 1900s are due to failed electrolytic capacitors, even in modern times. Most of the rest of that 1% is the doped ion maxtrix in a transistor becoming depolarized over time. Nothing lasts forever, and electrolytic capacitors are the cheap throwaway trash that make electronics a disposable commodity.

 

[Forgalspop]

@Dr_Mitch

I do not have the manual here in Oklahoma it is in New Mexico, but if my memory serves me, the manual did not address the error code pointing to a failed component.

I looked at all the capacitors the best I could and did not see any swollen or leaking capacitors. Like I said, I could see no indications of any component becoming over-heated or obvious signs of damage. I would have thought the fuses would have protected the unit, but none off the fuses were blown.

Live and learn. I should have went with a Samlex or other name brand at a higher price point, just like I should have gone with a Honda generator/inverter instead of a cheaper brand. I can't really complain about my Champion paired generator/inverters that are going on 7 years and many hours, but are getting long in the tooth.

Thanks for your reply!

 

[TerryMiller]

While our inverter (3000 watt pure sine wave Xantrex) doesn't have user accessible fuses, it does have three buttons on the side that are tied to breakers. If our inverter gets too much power pulling from it, one of those tends to trip and I have to go reset it. You didn't say anything about buttons, so I assume yours doesn't have any.

 

[Forgalspop]

While our inverter (3000 watt pure sine wave Xantrex) doesn't have user accessible fuses, it does have three buttons on the side that are tied to breakers. If our inverter gets too much power pulling from it, one of those tends to trip and I have to go reset it. You didn't say anything about buttons, so I assume yours doesn't have any.

Nope! No reset buttons. Should have gone with Xantrex or Samlex to begin with.

 

[Gunbuffer]

There will be a failed (internally shorted) electrolytic capacitor, or one of the MOSFETs, dumping current to ground causing the error. If you have an error code, the will be some kind of reference material in existence that will interpret the error code, however that may reside only with the OEM as trade secret in order to protect IP, which is extremely common for electronics even if purely a cultural holdover for circuits that now exist en masse from all producers. I would call the OEM and ask what the error code means and if it tracks to one of the two boards you reference.

If OEM can’t help, and you don’t see clear evidence of a component or circuit trace that “let the smoke out”, look at the capacitors that are shaped like cans for swelling on the top surface or oil leakage around the bottom. The caps that turn half waves into ripple current are where I would start. If the caps look fine, they might be fine and it’s more likely a MOSFET, but the reality is that >99% of electronics failures not caused by human malfeasance or natural disaster since electronic circuits were invented in the early 1900s are due to failed electrolytic capacitors, even in modern times. Most of the rest of that 1% is the doped ion maxtrix in a transistor becoming depolarized over time. Nothing lasts forever, and electrolytic capacitors are the cheap throwaway trash that make electronics a disposable commodity.

I’d say that qualifies as “guru”

 

[Rez Exelon]

I’d say that qualifies as “guru”

He's literally got "Dr" in his name. Although I'm not sure which is a higher ranking between guru and Dr.

 

[CHenry]

Dr doesn't mean MD, he could have a doctorate in electrical engineering, or similar.

 

[Gunbuffer]

He's literally got "Dr" in his name. Although I'm not sure which is a higher ranking between guru and Dr.

That’s from his last career as a proctologist

 

[user 51785]

Dr doesn't mean MD, he could have a doctorate in electrical engineering, or similar.

really! WOW who would have known