Inverter won't start, need troubleshooting tips

I’m helping an elderly friend with her inverter (Magnum MS4448PAE).  The inverter won’t start.  What happens is I hear a click sound from somewhere inside the inverter each time I press the start button on the underside of the inverter. The remote control is showing a fault (the red light stays on) saying High Volts AC.  

I have done a soft reset by holding down the on/off button on the underside of the inverter for 15 seconds.  After this soft reset, I can push the on/off button and hear the click four or five times.  After that, pushing the button makes no sound until I do another soft reset.  (This is a very interesting clue to me, but I don't know what it means.)

This system worked for about a decade, but finally I think the batteries wore out.  I went to help diagnose.  When I got there, the inverter was running and powering a light.  I tried disconnecting the breaker that connects the batteries to the inverter.  After I reconnected this breaker, the remote control came back on, so I know that battery power is reaching the inverter.  The remote showed and still shows a fault “High Volts AC”.  But after flipping this breaker off and on again, the inverter would not start again.  And resetting it doesn’t seem to clear this fault.

I replaced the old batteries with new ones, but the inverter still won’t start.

The remote indicates DC voltage is reaching the inverter.  

I called Magnum Energy tech support and they said it was probably something broken inside the inverter and to take it in for repair.  That will be a last resort - I want to make sure there’s nothing I’m missing or could fix myself first.  The guy did say there are no fuses or breakers inside the inverter - and he thought maybe there had been a surge of power when I reconnected the batteries that burned something out.  That seems like a design flaw if that could happen, though.  

One thought I had is, could the “High Volts AC” indicate there’s some kind of huge load being put on the inverter that is too much for it to handle, and so when I try to start it it immediately shuts off?  I thought I had tried disconnecting the inverter from the house to ensure there were no loads on it, but maybe I did that wrong.  My friend lives very remote so I won’t be going there for another week or so and can’t just try things right now, so I want to gather all possible ideas before I go back there.

Here are my photos of the system showing all the components: https://photos.app.goo.gl/Tkm186M6PS6G4dnN8

Anyone have ideas of things to try?  I read the inverter's owner's manual and it says if there's a fault that won't clear, to have the inverter serviced.  

Howdy,

Did you look at,

"High AC default, pg 52  • High Volts AC – This fault causes the AC input to be disabled because a very high AC voltage
(>150 VAC or >300 volts for export inverters) has been detected on the AC input.
Remedy: Remove all AC power from the inverter’s AC input for at least 15 minutes to
clear this fault. Ensure only 120VAC power is connected to each of the inverter’s AC inputs."

I will suggest if you can and haven't already done so, is to disconnect ac/house current from the inside of inverter, making sure there is no output connection, and reconnect battery power, maybe there would be a change.  Then reconnect ac and see if it works.  

I have master switches that allow me to just turn off different parts of system without disconnect. Surprised to hear there is no built in breaker, etc.

I do have and did set up my own off grid system(24 volts, outback charge control/inverter,etc} tri metric meter, system has been running over 25 yrs., but once again I am NOT an expert and at times feel very lucky to have NOT burned up EXPENSIVE equipment or MY HOME. Be Safe

Thanks Randal,

Yes, I looked at that bit in the manual -- there is a generator that is hooked up to the inverter AC input but the generator isn't running so I wasn't expecting that that had any effect.  However, the tech support guy at Magnum Inverter said that the "High Volts AC" could indicate high AC voltage coming into or out of the inverter - contrary to the manual.  I don't know which is correct.

randal cranor wrote:
I have master switches that allow me to just turn off different parts of system without disconnect. Surprised to hear there is no built in breaker, etc.

Yes there are breakers - when I say I disconnected the batteries I just mean I flipped the breaker in between the batteries and inverter - not undoing the wiring.  :)

Howdy

Philip.
Here in southern oregon we are lucky to have   alternative power and machine, Grants Pass, Oregon. I have posted his{Jerry Ostermeier), web address before.

Here it is again,   https://apmhydro.com/  

I did not buy my system components from jerry, but have now known him for years, and once i started telling him about my system and things, he has always been willing with free information, advice and some amazing stories. Summer 2019, during a big fire season, he made a house call to my place., a real treat for both of us.

anyway, if you don't have a "go to guy" with off grid questions, you might be able to run some stuff by him.  He builds micro hydro units but does all types of off grid set ups. I get my batteries from him.

Philip McGarvey wrote:I’m helping an elderly friend with her inverter (Magnum MS4448PAE).  The inverter won’t start.  What happens is I hear a click sound from somewhere inside the inverter each time I press the start button on the underside of the inverter. The remote control is showing a fault (the red light stays on) saying High Volts AC.  

I have done a soft reset by holding down the on/off button on the underside of the inverter for 15 seconds.  After this soft reset, I can push the on/off button and hear the click four or five times.  After that, pushing the button makes no sound until I do another soft reset.  (This is a very interesting clue to me, but I don't know what it means.)

This system worked for about a decade, but finally I think the batteries wore out.  I went to help diagnose.  When I got there, the inverter was running and powering a light.  I tried disconnecting the breaker that connects the batteries to the inverter.  After I reconnected this breaker, the remote control came back on, so I know that battery power is reaching the inverter.  The remote showed and still shows a fault “High Volts AC”.  But after flipping this breaker off and on again, the inverter would not start again.  And resetting it doesn’t seem to clear this fault.

I replaced the old batteries with new ones, but the inverter still won’t start.

The remote indicates DC voltage is reaching the inverter.  

I called Magnum Energy tech support and they said it was probably something broken inside the inverter and to take it in for repair.  That will be a last resort - I want to make sure there’s nothing I’m missing or could fix myself first.  The guy did say there are no fuses or breakers inside the inverter - and he thought maybe there had been a surge of power when I reconnected the batteries that burned something out.  That seems like a design flaw if that could happen, though.  

One thought I had is, could the “High Volts AC” indicate there’s some kind of huge load being put on the inverter that is too much for it to handle, and so when I try to start it it immediately shuts off?  I thought I had tried disconnecting the inverter from the house to ensure there were no loads on it, but maybe I did that wrong.  My friend lives very remote so I won’t be going there for another week or so and can’t just try things right now, so I want to gather all possible ideas before I go back there.

Here are my photos of the system showing all the components: https://photos.app.goo.gl/Tkm186M6PS6G4dnN8

Anyone have ideas of things to try?  I read the inverter's owner's manual and it says if there's a fault that won't clear, to have the inverter serviced.  

hi Philip,
I've seen that code before. At that time it was a short in the ac out wire. You can also see it if the generator is putting out an overvoltage and if I remember correctly if the transfer switch gets stuck. As mentioned above disconnect incoming ac from Genny, disconnect physically ac out to the house and try again. If it powers up problem is in the house wiring.  If the inverter throws a code chances are the main board has a bad component on it. The pae is a great inverter but magnum does not do board swaps they insist on inverter removal and shipping it out for repair.
Cheers,. David

David Baillie wrote:hi Philip,
I've seen that code before. At that time it was a short in the ac out wire. You can also see it if the generator is putting out an overvoltage and if I remember correctly if the transfer switch gets stuck. As mentioned above disconnect incoming ac from Genny, disconnect physically ac out to the house and try again. If it powers up problem is in the house wiring.  If the inverter throws a code chances are the main board has a bad component on it. The pae is a great inverter but magnum does not do board swaps they insist on inverter removal and shipping it out for repair.
Cheers,. David

Thanks David, this is really helpful.  Next time up there I will try disconnecting the AC in and out wires from the inverter to see if that lets it start.

Just to clarify, the "transfer switch", if I understand right, is for switching between grid power and a generator -- in this case it's off grid and there is just a generator that can feed AC to the inverter - so would there be a transfer switch in this case at all, with a possibility of being "stuck"?  Just wondering if there's anything there for me to troubleshoot there as well.

Philip McGarvey wrote:

David Baillie wrote:hi Philip,
I've seen that code before. At that time it was a short in the ac out wire. You can also see it if the generator is putting out an overvoltage and if I remember correctly if the transfer switch gets stuck. As mentioned above disconnect incoming ac from Genny, disconnect physically ac out to the house and try again. If it powers up problem is in the house wiring.  If the inverter throws a code chances are the main board has a bad component on it. The pae is a great inverter but magnum does not do board swaps they insist on inverter removal and shipping it out for repair.
Cheers,. David

Thanks David, this is really helpful.  Next time up there I will try disconnecting the AC in and out wires from the inverter to see if that lets it start.

Just to clarify, the "transfer switch", if I understand right, is for switching between grid power and a generator -- in this case it's off grid and there is just a generator that can feed AC to the inverter - so would there be a transfer switch in this case at all, with a possibility of being "stuck"?  Just wondering if there's anything there for me to troubleshoot there as well.

to clarify. The magnum  pae has a transfer switch built into it. When the generator fires up it waits 5 seconds then switches over to using the generator to power the house and charge batteries. They refer to that as the transfer switch. Another fun often found one is the secondary breakers. You have your main switch breakers if it's a pre mounted unit then the small round ones on the side left over from before the breaker box one for the generator one for ac out, make sure they are on as well ..

Interesting, thank you.  The manual doesn't mention this transfer switch at all.  Perhaps it's considered an internal component that the customer needn't know about.

Have you experienced this transfer switch getting stuck and how would you know, or what did/would you do to try to fix it?  I'd like to be prepared for that if it is the problem.

Philip McGarvey wrote:Interesting, thank you.  The manual doesn't mention this transfer switch at all.  Perhaps it's considered an internal component that the customer needn't know about.

Have you experienced this transfer switch getting stuck and how would you know, or what did/would you do to try to fix it?  I'd like to be prepared for that if it is the problem.

Yes I've experienced a seized transfer switch usually on older inverters in unconditioned spaces. I do not think it is field serviceable. All you can do is go into it with as many tricks as you can remember to trouble shoot it. Also be prepared sometime call it and get it fixed...
Cheers and good luck, David

Thanks David!

So what else...
The battery monitor on the magnum sometimes stops working and causes a fault light to go on. Their network is a little sensitive so with the main inverter power switch off you can try disconnecting it from it's red and blue power cable and the telephone cable that it plugs into.
Sometimes the whole remote dies which might cause a fault. Again with the main inverter off you can disconnect it completely, turn the power on at the breaker and manually turn on the inverter using the tiny button under the inverter near the power cables...
A few more tools for you.