No Shore Power

[Mubashir Hayat]

Last night the power at my site went out briefly. When it came back on, the inverters did not switch to shore power. I checked the voltage at the power source, and it is good. This morning the generator auto-started, and gen power is good as well. The master 50 amp breakers on the main panel were not tripped, but I cycled them anyway.

 

Any ideas?

 

Thom 1999 Angola XL-40 Dunedin, FL Still feel like a newbie

[Mubashir Hayat]

This is a total shoot from the hip response, but my reaction to your comment that you did not get shore power to the inverters, but did get generator power was to think first, shore power really wasn’t available, and then my second thought is if it was available does your transfer switch have an issue?

Often we can measure power on a circuit when there is no load, but as soon as a load is applied the circuit goes dead. That could be a bad connection or any other reason but the fact the generator power was getting through to the inverters suggest to verify if there really is shore power and then to make sure the transfer switch is functioning.

Jon and Di 2006 Liberty Elegant Lady, 2021
Jeep Grand Cherokee, 1950 Ford
Knoxville, TN

Owner of three Liberty Coaches since 1990

[Mubashir Hayat]

Is there a shore power breaker inside your bus?  What you wrote sounded like you checked the breakers on the campsite plug panel…  cycle the on the bus breaker too.

You need a beeping voltage tester. The kind where you can touch wires with it and follow the path of electricity to help figure out where it stops.

2003 Marathon XLII #827
2017 Wrangler Unlimited
Austin, Texas

[Mubashir Hayat]

So, I got an RV tech out to help with diagnostics. I’m in a different park now. The power at the pedestal is good. We tried to trace the thick power cord, but by the time it shows up at the Trace 4.01 inverters, it is already split in to two smaller cables. One goes to each inverter. The tech’s best guess as to the problem is that the shore power transfer switches inside the inverters are not functioning. I’m not sure without being able to check the power at the point where the big cable splits – wherever that is. It may be in the inverter/battery bay, but we can’t see anything unless we remove the cables and batteries that block access to the inverters. The cables are all really short – with no slack. Looks like a horrible option.

There is no sign of any separate transfer switches or any pre-inverter breakers.

If the problem really is the transfer switches in the inverters, I have lots of questions. Are parts still available for these units? Are they field-serviceable? Is thee anyone in the Phoenix area who is competent to do this work? Am I possibly looking at replacing the inverters?

Thanks.

Thom
1999 Angola XL-40
Dunedin, FL
Still feel like a newbie

[Mubashir Hayat]

I’m pretty certain all MHs have a transfer switch before the inverters. All my MHs have.

Don – 96 Liberty XL 40 ” Classic”
ATC Stacker
Bulverde, TX

[Mubashir Hayat]

Thom, my 94 Angola has a transfer switch. I’m sure yours does.

My transfer switch is mounted in the first bay driver’s side on the top of the bay. A gray box with a set of contactors and relays. The transfer switch defaults to the generator. Only when shore power voltage gets to the relay’s is the signal sent to the contactors to change position.

My first guess is a bad relay. They are easily replaced. Later transfer switch models may be different types but I doubt if Angola changed it by 99.

If the transfer switch shore power leads do not have power then another location to check is under the bed. My shore power reel is under the bed and there is a connection in this location to transition from the flexible shore cord to the more rigid wiring. Check these connections.

As a last step, check the male plug to shore cord connections. My boat twist type plug did give intermittent problems and I replaced it with a normal male RV type plug. You will have to trim the length of the prongs to get it to go back inside the tube on the side of the coach.

Good luck.

 

Joe and Becky Carter
Aiken SC

1993 Prevost LeMirage XL with 8V92TA and Allison HT 755CR

1994 Angola Conversion

2007 Jeep Liberty Toad

joe81au at gmail.com

[Mubashir Hayat]

Thanks Joe. Very helpful.

 

Thom
1999 Angola XL-40
Dunedin, FL
Still feel like a newbie

[Mubashir Hayat]

Thom, I am not familiar with the electrical set up of Angola. That makes anything I say suspect.

I do have Trace inverters. You said Trace 4.01. Is that the software update or model number? My inverters are Trace 4204, so may be a completely different animal.

Someone will be along with a greater understanding than I have, but I do believe my inverters handle the switching on their own without a separate transfer switch.

I have a difficult time comprehending not having a breaker on the coach itself after the shore power gets to the coach. Can you reach the lug on the inverter that your power cord attaches too? If so, you could check continuity between the blades on the end of the unplugged power cord and those lugs. That will tell you if continuity is broken somewhere by a transfer switch or a hidden breaker or something else.

Davy

 

Home is where you go when there’s no place else to go!
1995-96 Prevost XL Vantare
Detroit 60 Series
Toad-2017 Jeep Grand Cherokee
Toad-2006 Scion Xb
1997 Featherlite 24′ Trailer
http://www.boggsblogs.com

[Mubashir Hayat]

Thom,

I had a situation similar to yours. Couldn’t get the Trace inverters back on line after the shore power went out. I turned the inverters off, disconnected shore power, turned off all significant loads, turned the inverters back on, and then reconnected the shore power. Inverters showed that they were in bulk charge and after a couple of hours were back to float. In my situation I think that I was trying to get all working without shedding as much load as possible. Maybe a simple reset by backing off all significant loads, shutting down the inverters, and resetting the shore power will restore your power. Simple solutions first?

Doug

Owned by one Prevost
Doug and Jan, Charlie and Darby
2000 Vantare XLV #1117, 1999 Prevost chassis, no slides. Towing a 2017 Silverado 1500.
Eastern Oregon

[Mubashir Hayat]

Thom, if all else fails and you do need to take it to someone, call Taylor Tours in Anthem. They’re on the NW edge of Phoenix, they run a whole stable of entertainer Prevosts and work on many different conversions.

Dan & Judy Hilger
08 Marathon #1076
3rd Prevost owned
SW Iowa

[Mubashir Hayat]

Talk to Inverter Services, they’re an advertiser with us and very helpful.

Tom & Nancy
7 Prevosts Owned

[Mubashir Hayat]

Thanks to Joe, I was able to locate the transfer switch.The bus is now sitting in a recommended repair facility in Mesa. The techs determined that shore power is getting to the transfer switch, but not coming out. The problem now is finding a replacement. They have been working the phones, but they are not finding a replacement. Any thoughts short of installing a manual switch?

Thanks again folks. You all are life savers.

Thom
1999 Angola XL-40
Dunedin, FL
Still feel like a newbie

[Mubashir Hayat]

Can’t believe it needs to be replaced. Is yours not just 2 or 3 of the cube replays about 1 inch square with 2 or 3 (I’m at work and not near my coach for picture to send) contractors in the bottom of a metal junction box?

If so pull all of the relays and go to any electrical supply house and have them match them for voltage, current and one of them is likely has a timer. Just replace all they are plug and play, just note where the time delay relay goes.

if that does not fix it then remove the contractors and do the same.

if your model is in fact a solid state board controlled then you may be out of luck for a replacement board depending on make and model. In this case just google “50 amp automatic transfer switch rv”. That will bring up a lot of options. Finding one which allows ready connection in the current wiring configuration may be tricky. Even camping world should have one that works but you will pay for more install hours if they have to move some wiring around.

good luck.

Joe and Becky Carter
Aiken SC

1993 Prevost LeMirage XL with 8V92TA and Allison HT 755CR

1994 Angola Conversion

2007 Jeep Liberty Toad

joe81au at gmail.com

[Mubashir Hayat]

Any RV repair shop should have a transfer switch in stock or can order one.  Very common item.

1998 Prevost Vision XLV

[Mubashir Hayat]

Send a pic of the guts of your transfer switch. If is the same as mine I can send the wiring diagram tonight when I get home.

Joe and Becky Carter
Aiken SC

1993 Prevost LeMirage XL with 8V92TA and Allison HT 755CR

1994 Angola Conversion

2007 Jeep Liberty Toad

joe81au at gmail.com

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