Magnum Inverter

[Don and Kathy DuCharme]

Our ME2012 Magnum Inverter is misbehaving.  Periodically, it will shut down.  Then need to press the on/off button on front of the inverter to restore function.  Sometimes it will function properly for several days and other times it is necessary to re-set several times within a couple of hours.  Have not been able to associate the malfunction with any particular circumstance.  When the inverter shuts down we still have shore power to the 50A circuits, but not the 30A so no power to the 110 outlets.  Appreciate any thoughts anyone has to offer. Thanks,
Don

[Edward Buker]

Don,

Are there any error codes saved on the unit? I would call Magnum with what you know about the problem. One thing you can check is that the current level being sent to the batteries is normal. Being on a 50amp power pole without appreciable 12V lights on I would think you should be in the 1-3 amp range after having been on shore power for an appreciable time. If you are getting a lot of current draw you could have a battery issue that could possibly be driving a fault.

Later Ed

[Don and Kathy DuCharme]

Thanks Ed,  I don't find any faults on the unit, but when the problem occurs the remote indicates an "internal fault". When all is normal like now the current being sent to the batteries is low (4A).  The problem has been intermittent for the past year, but more frequent the past couple of months.  I will call Magnum and see what they say.  
Don

[Edward Buker]

Don,

With the current that low the batteries are fine. If you have seen no signs of significant power dropouts in the form of flickering 120V lights and such then it does not seem likely that supplied AC issues could be driving this. Probably the most you can do is to verify that all of the wiring in your main AC breaker box is tight. Tighten all the neutrals, grounds, and breaker wires. Then check the wiring and be sure the AC wires within the transfer switch terminals are tight and then the AC and DC inputs and output wires on the Magnum unit. If all of that is normal then you have done all you can. Just be certain that the AC main cord is unplugged and the Inverter is off when doing these terminal checks. Tightening all of this one time while you own your coach is a good maintenance check.

Later Ed

[Don and Kathy DuCharme]

Thanks again, Ed.  I talked with Magnum this afternoon and the tech thought it is probably the circuit board with the re-set that is the problem.  He gave me a service center here in Fl. where I can purchase the part.  I am going to check all connections as you suggested before throwing parts at the problem.  
Don

[Edward Buker]

Don,

More than likely it is a Magnum internal problem as the tech described. At least if you know all the AC connections are tight, then you can head for the board replacement in good conscience.

I have seen intermittent neutral wires and floating grounds that are poorly connected cause electronics to misbehave but it is a bit of a long shot here. You have nothing to lose but an hour or two. In the end you will be comfortable that your AC wiring is as it should be. Good luck on your hunt.

Later Ed

[Don and Kathy DuCharme]

Inverter update.  Replaced the primary circuit board nearly a week ago, and no problems to date.  Will keep our fingers crossed for the next month or so and hope the problem does not re-occur.  Thanks for your help.

[LEAH DRAPER]

Could also be a mouse....I had a problem with them chewing thru the remote cable.

[Don and Kathy DuCharme]

Leah thanks for the suggestion.  I checked that out when the problem initially occurred, since a family had decided a year or so ago that the area on top of the inverter would be a good place to build a nest.  I suppose there is a bit of warmth there even in the midst of a Mich. winter.