Inverter Problem.....I think ??

[blacklab]

On my '95 Royale we used to be able to run the front roof air and/or the microwave off the inverters. 2X 2500 Heart. On our last trip when we were not running the gen, the microwave wasn't powered up while running off inverter power. The batteries were '01 vintage so I bought & installed new AGM's. Still no power to microwave or roof air, but everything else works as it should (I think). I noticed that the converter charger wasn't working/humming as usual so I checked the outlet it was plugged into & it had no power to it. No blown fuses either. So I plugged it to extention cord and it is now working. After 4 days of charging, still no inverter power to microwave. Where do I start??

[Jon Wehrenberg]

Blacklab....

This is a generalization because I am not familiar with how Royale wired its inverters. Heart has as many as 9 ways to install the inverters so I will speculate a little. First, the facts, then the guesses.

Your inverters need a circuit of 120 VAC to power them. You do not say what specific model you have for inverters, but regardless there is going to be one input, or two. The inverter input(s) need power so verify the breaker to the inverter has not tripped, and then verify you have power to the inverter input(s) at the inverter.

If the inverter has dual inputs one may be labeled transfer and the other charger. If it has a single input it will be labeled as such.

Verify the circuit breakers at the inverter face have not popped.

If you have power to the inverter, and the breakers have not tripped you should have power to the inverter output. Verify that. If you do not have power out, but have power in the inverter is not functioning as an inverter. Check the DC voltage at the house batteries to see if the inverter charger is functioning. If the charger is functioning you should have at least 13 VDC (26VDC) with no load, and likely a higher voltage. Less than that the inverter charger is not working.

If you have two inverters the probability that both have simultaneously failed is slim. If all but only one circuit has failed focus on that single circuit. Has the breaker tripped. Does the microwave have a GFCI receptacle that has tripped? Is there a fused protection at the microwave, such as in the rear of it?

If the inverters are working you will hear a hum, you will likely hear the cooling fans cycle on and off, they will feel a little warm, and you will have power in and out. If that all checks out on both inverters the problem lies elsewhere.

If you can get more specific it might be possible to zero in on the specific issue.

[Jerry Winchester]

I'll bet it is a ground problem.

[blacklab]

I have no AC output on the #2 inverter, so i'm thinking that #2 would power the items not getting power now. BTW, the converter charger reads 28.91 volts. Should I replace both inverters? They are original to the coach.

[dalej]

I would move slowly on this, two new inverters is not considered a small fix, $$$.

I would check to see if you have a transfer switch, its a small 5 x 5 inch or so box that switches A/C and inverter power to the house. I have lost two in 9 years, so I would check little things first before starting to replace things to find the problem.

[blacklab]

Any Royale owners out there know where to look for this?

[dalej]

When you plug your coach into 120v do you hear a relay type sound in the electrial bay? If in your electrial bay you have a 220 breaker marked shore power, turn it off and listen, then turn it back on and listen, you should be hearing the tranfer switch moving from inverter power to shore power.

[blacklab]

Yes, the transfer switches are working. The more I think of my problem, i'm associating the non-working receptacles and appliances with my one inverter not working. I just assumed that to power up the roof air and/or microwave a guy would need two. It seems that just one 2500 watt inverter is wired to handle the bigger draw items. I'm just thinkn' here.

[Jon Wehrenberg]

Blacklab.

Your question is timely because I just finished an article on installing an inverter by-pass in case an inverter fails. Go to the POG site and look under Articles. It is the first one listed.

To diagnose your problem let's get specific. Do you have power to the inverter you think has failed? If not, check the breaker supplying power to it. Also, check the circuit breakers on the front of the inverter to make sure they are not tripped.

At the voltage DC that you specified one or both inverters appear to be charging. Lets not worry about that now.

If you are getting power to the inverter, and the breaker CB's are not tripped, are you getting power on the inverter output? If not then all the circuits powered through the inverter should be without power. It sounds like that is the case.

You cannot assume if one inverter fails, the other will pick up and handle the load. Each inverter has circuits it alone handles, and when shore or generator power is available a transfer switch internal to the inverter closes and supplies power to those circuits, while also activating the internal battery charger. I do not know how Royale set up your inverters, but it sounds like there is no automatic by-pass for a failed inverter.

Let's assume you determine there is no power output through the inverter. Turn off the other inverter to determine if the batteries are receiving a charge through the inverter that has failed. If so it is likely the transfer switch portion of the inverter has failed and you can replace the board or the inverter. We can talk about that once you check some more. Replacing the board is very cheap compared to a new inverter and is not difficult to do. The article also will give you some insight, and you may wish to consider a by-pass switch or for the moment connect the input and output wires to power the circuits you lost.

[Jerry Winchester]

The relay for my Royale was in the plumbing bay where the shore power cord hooked up. And it had a breaker right there, so that had caused me some problems.

You should also be able to use a VOM to read the inverter input and output voltages as I think the connections are all on the bulkhead to the left of the inverter. Our Royale also had a big honkin fuse right there for surge protection.