AC power problem

[TDJohn]

Jeff,

It does sound like you have two different issue. You mentioned in an earlier post, that if you manually turn the inverter on to invert, the circuits on the inverter energize. That means that there is no issue between your inverter output and the inverter circuits. The 30amp breaker at the main panel, that feeds shore power into the inverter needs to be checked/tested and reset to make sure it is providing shore power into the inverter. The shore power that gets fed into the inverter does two things. It allows for the inverter to charge the battery bank (unless you turn the charger off at the remote), and it allows shore power to pass through to feed the inverter circuits. On my MS2812 inverter, there are two button type breakers on the side of the inverter. One is a 20amp breaker that protects the inverter charging circuit and the other is a 30amp (30amp X 2) push button breaker. Depending how your inverter is installed, they could be well hidden, but they should be there. Feel around for them. Also, as Brett suggested, test the operational function of both a/c units. If they both function on shore power, it is very likely that you are missing a GFCI outlet somewhere or you have a defective one. The refrigerator circuit very likely has a hidden GFCI outlet somewhere in the basement.

Also, what fault code are you getting on your inverter remote panel?

If you like, I can try my best to walk you through all the testing procedures over the phone, just send me a PM with your contact info and I will give you a call. (don't be shy).

[ProCycle]

Hey John, thanks for the offer of help but I have good a handle on doing the testing. I have done plenty of this sort of stuff before, just never dived deep into the inverter system on an RV. It was definitely confusing at first but I'm confident I understand how it's all supposed to work. I've verified that power is getting through the 30A breaker. So it's good up to that point. I've also verified that there is no AC power getting to the input on the inverter so the problem is between the two points. There is a junction box in the back of the electric bay that all the AC invert wires pass through. It's a safe bet the problem is in that box but I'm not going to sit in the rain to work on it.

I've also verified that the inverter does not have any breakers of its own. It's spelled out in the manual that this model is shipped with no breakers in the outputs.

"Note: The model shown is not a -15B or -20B model, therefore it does not show any AC output
breakers. Models without output breakers (CB1 & CB2) use carriage bolts to fill the breaker openings."

There is a place on the side where they could be installed but the holes are blanked off with carriage bolts. Whoever installed this inverter should have added a sub panel with breakers but they didn't. Once I get it all sorted out I'll add my own sub panel.

I misspoke earlier when I said there were NO breakers. It does have a 30A input breaker on the side of the inverter which has not been tripped.

The remote panel doesn't show a code just red letters that say "Inverter Fault". Not very helpful...

[TDJohn]

Sounds like you have partially isolated one of your problems, hopefully it will be a simple fix.

If your willing to go on a wild goose chase, I have seen some later model ('99 to '01) coaches that have a sub panel for the the two inverter circuits, hidden in the bedroom. Most are well hidden behind the bedroom TV, some were hidden in one of the cabinets. Your coach being a '97 is in between, so it might not have the sub panel, but it might be worth the look, as it would save you some trouble installing a sub panel. If you don't have one, Lowes sells a very compact square D 30amp sub panel that holds two circuit breakers and would fit snugly in the inverter compartment.

I hope you get everything resolved w/o too many headaches. Please keep us updated on your progress.

[ProCycle]

So I got a chance today to have a good look at it. All the connections in the junction box just had wire nuts screwed on to straight wires. None were twisted together as they should have been. The wire nut on the 30A input connection was damaged. The metal cone inside the wire nut had been pushed way down into the end of the wire nut. Sloppy work by whoever installed this inverter.

There is only one AC output wire coming from the inverter. It was connected directly to 2 wires to feed the 2 inverter supplied circuits. I'm lucky there wasn't a worse problem. Those 20A and 15A circuits were only protected by the single 30A breaker in the breaker box.

I picked up a small sub panel and appropriate breakers and I'll put it all back together properly. Then I'll go hunting for any other potential problems.

[TDJohn]

This was years ago, but my inverter was replaced a year before I bought my coach, and by ordering the wrong inverter and/or failing to install a sub panel, they created the same dangerous situation as you have. I discovered all that mess when I upgraded to a Magnum MS2812. This is the kind of headache that is actually a blessing in disguise.

[ProCycle]

Yes. I now have it wired correctly with 2 breakers in a sub-panel and it's no longer dangerous. Unfortunately the poor connection in the AC feed must have damaged the inverter. I still have no AC passing through the inverter when it's turned off. It is also not charging the batteries. Next step is to pull it out and send it away for repair.

[TDJohn]

Not so fast, I would suggest a few things to do and check first. Check to see if the 30amp power input breaker is possibly defective and not resetting. Have you tested for power at the inverter where the input wires connect to the inverter? Do you have power at that point?
I would suggest to do a soft reset of the inverter. Instructions should be in your manual, but if memory serves me correctly, you shut the inverter off and remove all communication cables (phone cables) from the inverter for like 5 or 10 minutes. If that doesn't work Magnum often suggests doing hard reset, which involves disconnecting ALL power from the inverter for 10 minutes. This is shore power and DC power. I would also suggest to give Magnum a call and see if they can walk you through the troubleshooting (their tech support is decent) before you go removing and sending the inverter out.

One last thing to try and check on. Depending on how advanced the inverter remote is, some of them have a special section in the menu for trouble codes, the trick is finding it to get in. Once in, it should display in the trouble codes menu all your recent trouble codes. Your remote might not be advanced enough to have that option, but it is worth a try in case you do have it. In any case, as soft or hard reset might wipe the trouble code out and restore you proper function of the inverter. Best of luck!

[ProCycle]

I've have done both a soft and hard reset. I do have power to the input terminal where the wire connects inside the inverter. The only way to get power to the output terminal is to turn the inverter on. There is no pass through when the inverter is off. My remote is an older Silverleaf. I've been all through the menus and can't find anything about trouble codes.

Once I remove it I'll pop the cover off and see if there is anything obviously burned up or a cracked solder joint on the control board.

[TDJohn]

At this point, is your inverter still capable of charging the batteries on shore power?

Unfortunately, it sounds like the bad connection that you had on the 30amp input circuit probably overworked and destroyed the internal transfer switch in the inverter...

[ProCycle]

The inverter is not charging the batteries. I'm sure you are correct about the overworked and fried transfer relay. I can imagine the loose connection bouncing and vibrating for a couple thousand miles flipped that relay about a million times.

Luckily there is an authorized Magnum repair center only 100 miles away.