Shore Power Switching to Inverter Power

[andrews.thomasw@gmail.com]

Here is our electrical problem with our 40X 2008 Fleetwood Discovery: The shore power is coming in as normal. We are plugged into the CG provided 50 amp power at the pole. This power switches to inverting. The shore power breakers at the pole are not blown or flipped off. Also, there are no breakers thrown in the breaker box inside the coach. To fix the situation, we flip the pole breakers off and back on (maybe don’t need to do this but we do), press the three switches on the side of the magnum inverter and turn the inverter off and back on. Everything comes back to normal, meaning that we have full shore power with no inverting. We have the “MS Series Pure Sine Wave Inverter/Charger.”

When the problem occurs (power switches to inverting), the microwave or dryer is usually running, but not always. It used to only occur if the microwave or convection oven (within the microwave) was running for more than 10 minutes. Now the problem is occurring with very little increased amperage.

We had a mobile RV technician come and he tested the power at the CG pole. He suggested that the breaker at the pole be replaced. The CG owners did this. He also checked the power in the breaker box inside the MH. He said it was fine. The technician said the microwave is wired through the inverter. He suggested replacement of the electrical outlet box in which the microwave plugs into. That was done.

We still have our problem. It is occurring multiple times a day now. We have had this problem at other campgrounds. Since this CG has changed the breaker and we’ve had the problem before this CG, I don’t think it has anything to do with the CG power.

Any suggestions on what may be happening and how to fix it? We are currently in the Rio Grande Valley in south Texas. Any suggestions as to who to use for RV electrical repair?

[desertdeals69]

Are you saying that the inverter is on when you have power from the shore cord? If you do then maybe the transfer switch in the inverter is not working.

[dickandlois]

Andrew, Could you run a little test for me?? Disconnect from the shore power and run the Generator for a period of time to see it the problem you described happens. and post the results. Looking for a bounding issue with this test !!!!

There is a J box connecting the generator wiring to the ATS, and wiring issues in this box can cause some issues.

I would have an electrician check all the ground connections and I mean ALL of them including the Battery terminals, chassis,inverter connections, and all the Neutral screw terminals and ground terminals in the breaker box.

There is a #6 copper wire running from the inverter to the Chassis frame. This is the ground for the inverter, tying it to the ground from the CG power. The Camp ground, ground is also wired (Connected) to the Chassis frame with a #6 copper wire running from the Circuit breaker box ground buss. Make sure they are connected tightly to the chassis and at the Inverter and breaker box. This is best done by an electrician.

The Circuit breakers in the panel are numbered 1 to 7 and 11. Circuit breakers # 9 and 10 are at the inverter. No # 8 Circuit breaker !!!!

The Inverter power feed is from the breaker box but no breaker is in the line as pictured in the information I have of the circuit breaker box itself. However ! an AC feed is pictured in the block diagram running between the box and to the power input for the inverter.

NOW ! Thinks get interesting... You have a dryer, so you have option #6 per my information ( meaning breaker #6) is used for the clothes dryer in the info I have and this circuit is wired different from all the others and needs to be checked by a good RV Tech. With the proper wiring information, an electrician might wonder what is going on regarding this circuit !!!!!

Rich.

[wolfe10]

If, repeat IF you are safe working around 120 VAC, with all power off (disconnect from shore power, generator and generator auto start off, inverter off) check all connections. This should be done once a year on all RV's.

Check connections where shore power comes into coach, ATS and all the screws (hot, neutral, ground and main feeds) in the 120 main breaker box. Also look for burnt wires that would indicate poor connection (poor connection is resistance-- resistance with power going through it is HEAT).

Also, as a troubleshooting issue, put a voltmeter on the other microwave socket and monitor voltage when this occurs. If voltage drops to a low enough point (due to loose connection or other issue) it would be reasonable that the inverter is sensing "insufficient" voltage and is kicking in to power your appliance.

[bobbyks]

Are you saying the inverter should not be on when connected to shore power?

[dickandlois]

There is no reason for it to be running when plugged into shore power, the two circuits powered from the inverter will get power directly from a feed coming from the Main AC panel. The same goes for when you generator is running.
The only exception might be if you use it to power you computer and only then if its a tower system, the laptops will see the power loss and go to a save files and power down configuration.
I use ours to power the computer and other items when driving, it can easily supply enough power for items needing 110 AC. The alternator puts out enough 12 volt voltage and current to keep the chassis batteries and coach batteries charged. Not all coaches are set up the same way and some do not charge the coach batteries while driving. So one needs to know just how there unit is configured.

The way my coach is set up. When I have had an alternator fail. I disable the exciter circuit at the alternator, Start the Generator and use the Charger / Inverter to supply 12 volts for the engine circuits and lights. The inverter powers the 110 volt circuits also.
The charger current outputs vary depending on the make and size, but 30 amps will run a lot of items. One could carry a Battery charger that could be plugged into a 110 outlet in the bay with the cables connected to the common point between the chassis and coach batteries to keep things running if one looses the alternator output and the alternator can be used as a pulley to keep things like the water pump working. There are some nice workarounds one can use once they understand the systems and how they work on there particular coach.

Rich.

[bobbyks]

Rich, I am little fuzzy on the inverter/charger system, some things come a little slow in South La., if I understand you when I am connected to shore power I can turn the inverter off , leave the charger on, the batteries will charge as needed. Should I turn the inverter on at any time while on shore power?

[dickandlois]

Bob,

Do not feel bad or that you are slow. It can be confusing to most. Look at it this way, You have a charger / inverter. When the generator is running or you are connected to shore power the charger is running all the time. All your AC needs are supplied from shore power or the generator and those sources feed ac to the input of the charger and are coupled through by a relay circuit to the 2- 120 VAC circuits at the output of the inverter. No 12 volts required from the coach batteries to provide 120 VAC
The inverter portion only puts out 120 AC when turned on, the inverter electronics gets 12 volts from the batteries and the alternator if the engine is running.
A relay disconnects the 2- 120 VAC outputs for the incoming AC source and connects them to the output of the inverter. You now have the use of 2 -120 circuits.

Generally the microwave and one circuit that feeds the outlets at the front (Driver, passenger seat area, overhead area with the DVD,TV and the outlet(s) in the storage above the dash plus the dinning area.

There is no need to have it powered up unless you want to use it as a UPC powering computer equipment. No other advantage and remember you are using up battery power because the charger is now disconnected to prevent a feed back loop issue. If the engine is running the batteries will keep charging.
If you have a voltmeter and switch things on and off you can read the changes in battery voltage levels and find the Outlets powered by the inverter.

Hope I helped answer your question.

Rich.

[snybe]

We are also having sort of the same issue with our 2011 Fleetwood Discovery 40G.

I have noticed that sometimes when hooked to shore power the 110V outlets loose power in the main coach as if a breaker has tripped. The only way I can get power back to them is turn on the inverter.

Last night we had the inverter on for the coach power with hardly anything plugged in and when I woke up this morning, even though my panel showed we had 50A service, the house batteries were at 10 volts, like the converter was not working.

I have noticed that when I do loose power to the 110V outlets, the 110V outlet for my dryer still has power along with the hot water tank.

So I went outside to check the breaker box at the electric pole and it seemed fine, but I turned it off along with the power switched at the entry door and let the coach sit for a minute before turning the power back on. Now the coach would not recognize the 50A service and the Power Guard panel was showing a 02 (ground error). I had to run the generator all day just so our batteries did not go dead but then had to start the engine because it seemed the generator was not charging the batteries that good.

Now I have shore power again and my batteries seem to be staying around 13.2 volts, but I can only get 110 in the main coach through my inverter still.

I have two inverters, one for the coach and one for the fridge. It seems the one for the fridge does not have to be on for its power when hooked to shore power like for coach power.

Is there a switch bad or something? I will get this checked out when I take the coach back in for service this March, but that is still a ways off.

I hope you figure out what is wrong with your system, because I bet it will apply to mine as well.

Thanks!

Don

[dickandlois]

Hi Don,

Could you list the model and make of your charge / inverter for the group?

The fact that you only get power to the 2--110 volt circuits wired from the inverter only when its running, kind of tells me there is a relay issue. With more information I can look into things a lot better.

Rich.

[snybe]

Rich,

The inverter is a Magnum MS2000.

Thanks!

Don

[wolfe10]

Another cause of only some outlets having power is that they go through a GFI and that GFI is tripped. Locate ALL your GFI's and hit "test" then "reset/on".

[snybe]

Brett,

I have checked them all and they are good, plus if one was tripped, switching over to the inverter should not make a difference, should it?

I also want to apologize for hijacking this thread with my problems. If need be I will start a new thread for my issue.

Thanks!

Don

[dickandlois]

Thanks Don,

The model you mentioned has an internal relay. I have to check and see if the BCC control board has a circuit working in conjunction with the charger / inverter.

Do you have the manual for the BCC unit ? There could be a fuse inside that box that has failed.

Could you clarify one more item for me.

You mentioned the batteries discharged over night. That kind of leads to the charger side of the inverter not working. Think from your first post that the only way you got the coach batteries to recharge was running the engine-- kind of missed that the first time I read your post.

Can you hear a hum coming from the charger while connected to shore power? The inverter is powered through the main breaker panel, so if you do not have a 110 volt input to the 2000 unit then you would not have the 2 --110 volt circuits you mentioned and this would also lead to a issue of charging the coach batteries from the generator or shore power.

Rich.

To reset the inverter:

Press and hold the Power ON/OFF push button for approximately fifteen (15) seconds until the

Charging/Inverting Status LED (see Figure 3-5) comes on and flashes rapidly; once the rapid

flashing has begun, release the Power ON/OFF push button. The Status LED will go off after the

push button is released.

[snybe]

Rich,

That was the problem. After properly resetting the inverter, everything is working as usual.

Thanks so much for the help and I will make sure to remember this so if it happens again, I know exactly what to do.

Don

[NikkiM7]

I have a somewhat similar, but different inverter issue - maybe. We have a 2007 Fleetwood Revolution LE with a Freedom 458 remote panel. We recently built a new shop to store it in (yeah) with a 50A service. Prior to that we only had 30A service to plug into. The remote panel used to always have solid lights showing what was coming in and what appliances were supported. Now the panel just flashes vertically up over and over. It seems weird. We have only dry camped once since this started and our batteries got really low over night just running the heater. This was not an issue previously, we could watch tv, run the heater, whatever and not lose battery strenght overnight. Not sure what is going on. Maybe the flashing is normal at 50A, but it doesn't seem normal. It is all confusing. Any thoughts from you advanced members?

[dickandlois]

If you have a MS-2000 series inverter / charger, press and hold the power / reset button in for 15 seconds. When the green LED starts flashing release the button and see it the unit resets. Light will stay off !!

Should this work and then the inverter act up again, Check your neural and ground connections from your shore power riser to the input of the coach and all the bonding points between the AC breaker box and chassis.

The bonding wire is the bare copper #6 wire running between the AC breaker box to the frame and the same size wire running from the inverter / charger to the frame.

A loose connection could be causing the inverter to switch from power line feed, to running on battery power if its sensing an imbalance between the neutral and ground systems.

If you are not sure how to do this safely, get an electrician to check all the connections for you.

You mention in the Generator problem that the fuel pump has running running even after replacing the stop switch, so this leads me to really lean towards a ground / bounding issue(s)

Rich.

Note! this thread has a similar problem.

http://community.fmca.com/topic/5134-help-no-power-to-half-the-ac-outlets

The Difference between inverter models can offer up a problem that looks close, but the problem can be the circuit breaker(s) or the internal 30 amp circuit breaker that feeds AC to the inverter. This is a push to rest breaker that needs to be pressed. Location is on the left side of the inverter with the number 30 printed on it.