Electrical Conundrum

[Mjw2347]

On a 3 week road trip and I have an electrical issue and would appreciate some help/advice.

1)Currently shore power is not working.
2)For a short time only a few outlets and the refrigerator worked on shore power but now nothing works.
3)The generator is working properly and the alternator is also recharging the batteries while we are driving down the road.
4)I had a RV service tech in Utah try to diagnose and fix this problem but he was only able to get my inverter working by replacing a bad fuse (Freedom 458 inverter).
5)With the inverter now working and after a bit of research I’m wondering if I have a transfer switch problem. If so, how do I confirm this is the root cause and next — what is the fix?

We are currently in Fort Collins, CO for a few days so if anyone knows of a crack RV tech in the area please let me know so I can get this problem resolved. Thanks!
-Max

[Dave Fernandez]

I think you diagnosed the problem being the transfer switch. The fix is replacement. It is located in the bays forward of the holding tanks on the ceiling. It is a fairly easy task just about RV store should have them in stock.

[YC1]

To be clear. The generator does make the inverter/charger work? And some of the outlets did work on shoreline.

Easy enough to check the transfer panel as mentioned. There may be a schematic on the inside of the cover to help or find one online.

IF you have an electric reel that could be causing the problem but more likely it is the transfer panel.

In a pinch you could bypass it or maybe swap the generator input with the shoreline input. A new one is not that difficult to change but one needs to take pictures first.

[Jeep401]

We're you plugged in directly to a 50amp plug or were you by chance using an adapter? If a adapter is being used, it is mostly where the problem is.

[oscarvan]

Yes, sounds like the transfer switch could be the problem. The tech should have looked in to that.

Follow the shore power cord in, it will lead to a box. When switching between sources you should hear pretty audible "CLICK" coming out of this box. (It's the relay driven contacts flopping back and forth)

It's job is to allow EITHER the generator OR the shore power in, as both at the same time is not good.

There are a few different designs out there, but most likely with the generator OFF and plugging in the shore power you should hear it. MOST transfer switches will favor the generator. SOME are at rest in that position. MANY are dual relay and EITHER will close when power is applied, with the generator having priority, and never both at the same time.

If you don't hear any clicking it's time to go in there with a volt meter and see what the transfer switch is doing.

(Some people have had results "whacking" the box to shake the relays loose, but that's not really a fix)

[Mjw2347]

Thanks for the immediate responses... 1) Yes, the generator makes the inverter work. 2) I have been using an adapter because 50 amp is not available. Off to Walmart to pick up a new adapter. 3) I will also try to replace the transfer switch if I can find one in FC...

[Jeep401]

Originally Posted by Mjw2347

Thanks for the immediate responses... 1) Yes, the generator makes the inverter work. 2) I have been using an adapter because 50 amp is not available. Off to Walmart to pick up a new adapter. 3) I will also try to replace the transfer switch if I can find one in FC...

I suspected, not uncommon to cause problems. I don't know for sure, but I don't think the transfer switch would only cut out one leg of your 110v, which sounds like what was going on, but it could be, I'm just not sure on that part. New adapter is cheap and easy to try first.

[Sbrownstein]

This could all be an adapter or cord problem. Since the generator works that means that half of the transfer switch is working correctly. You could have a bad contact or coil in the transfer switch relay.

However, the first thing that I would verify is that you have both legs energized AT THE TRANSFER SWITCH from the shore power cord. If you are not comfortable with measuring voltages...do not do this. If you are, remove the cover and verify that you have 120 volts between the black and white and the red and white coming from the shore power cord. You should also hear a "clunk" when you plug in the shore power cable, which would be the shore relay pulling in. If it doesn't clunk, you either have no power to the switch or a bad relay coil or control board.

[Jim28730]

X2 on the transfer switch.....

[Old-Biscuit]

Either the transfer switch (as discussed) OR the shore power cord

First symptom was the 'partial; working issue (fridge/some outlets---probably all fed from same bus bar)
Then nothing worked on shore power


Need to open transfer box and check/tighten ALL wire connections...shore in/gen in and main out---ALL AC Power OFF!!!!


Then plug in shore power cord and test that both legs are HOT (L1/L2)
Both hot...then test Main out. No main out---bad relays/connects in transfer switch


Both NOT hot..bad power cord

[paul65k]

My first thought was the transfer switch......if that's not the issue it ce the inverter not passing power through....something worth checking

[JLMunsil]

There is a Camping World about 25 miles south of Fort Collins on I 25. Also Trans West in Frederick Co works on Motorhomes. They are 35 miles south of Fort Collins on I 25.
Trans West does good work. I don’t know about Camping World but they may have parts.

[Mjw2347]

Update — Found a local RV service center (Nathan’s RV Service) in Fort Collins that carved out some time for us today. He determined my Inverter is defective and quickly designed a viable work around the Inverter so we now have shore power to get us through the balance of our trip. Will need to get the Inverter fixed or replaced when I get back to Southern California. Thanks for all of the comments, support and help...

[veraken]

Here's a short video on how to test your transfer switch

https://www.youtube.com/watch?v=TpPkj8aTcyE