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Lost 30A service [message #333725] Tue, 19 June 2018 20:40 Go to next message
Deb is currently offline  Deb   Canada
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Registered: October 2016
Location: Logan Lake, BC
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Pulled into our site this evening plugged in the 30A turned on the ac and came back 5 minutes later to find no power and the 30A adapter hot.

Have had no problems running the ac before. Looking for a main breaker. P.O. has installed an intel lip owner inverter. Any idea where to start??

Hotter than a bear in here tonight.


Deb McWade Logan Lake, BC, CAN GMC Alumnus It's Bigger on the Inside!
Re: Lost 30A service [message #333726 is a reply to message #333725] Tue, 19 June 2018 21:03 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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The fact your 50 to 30Amp adapter was hot shows there was a poor connection within the adapter or its connectors. I would suspect the adapter first. Maybe a neighbour could loan you one to test.

The campground store may have them for sale.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Lost 30A service [message #333727 is a reply to message #333725] Tue, 19 June 2018 21:06 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Start at the campground box. The the panel in the coach. I can only guess your floorplan, but should be a breaker box accross from your bathroom door in the cabinet.

If you are running BoTh A/C units off the 30 amp you are going to heat up that cord.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Lost 30A service [message #333734 is a reply to message #333727] Tue, 19 June 2018 22:25 Go to previous messageGo to next message
Deb is currently offline  Deb   Canada
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
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Senior Member
Thanks folks. We tried another campsite - no go. No one else had a spare they could loan us to test (not many folks around tonight for some reason) Breakers were all good - nothing tripped, and no blown fuses on the inverter. I had run both ac at once on the 30A past couple of days but must have been lucky!! And of course the Onan was being stubborn on start up and I didn't want to drain the house batteries.

Campground office is already closed, so I guess it's off to Walmart for a replacement adapter and crossed fingers that was the problem From what you are both saying, certainly sounds most likely to be the culprit.

But, as problems go, so far, mine have still been less than monumental - one blown fuse, one hot fuse holder (cleaned up the connection and no more hot!) the spring in the awning pin broke so we had to push it in one hole at a time to close the awning 2 days ago. Now this. But nothing earth shattering, nothing trip interrupting. Just another learning experience and something to write in the trip journal!


Deb McWade Logan Lake, BC, CAN GMC Alumnus It's Bigger on the Inside!

[Updated on: Tue, 19 June 2018 22:25]

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Re: Lost 30A service [message #333735 is a reply to message #333725] Tue, 19 June 2018 22:34 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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I carry a couple adaptors. So i can plug in about anything. My 30 amp to 15 amp cord and my fan came in handy on saturday to verify a 30 amp campground outlet was dead.

I also keep one of these:


https://www.walmart.com/ip/Power-Gear-3-Wire-Receptacle-Tester-50542999/16561511?wmlspartner=wlpa&selectedSellerId=0&adid=22222222228016731164 &wl0=&wl1=g&wl2=m&wl3=40873258712&wl4=pla-78765756632&wl5=1020086&wl6=&wl7=&wl8=&wl9=pla&wl10=8175035& wl11=online&wl12=16561511&wl13=&veh=sem

Tells me pretty quick
If there is power or not


Let me know if you need anymore assistance or a place
To park. Just off i-94, st. Cloud, MN exit 171.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] Lost 30A service [message #333754 is a reply to message #333735] Wed, 20 June 2018 14:02 Go to previous messageGo to next message
w schurman is currently offline  w schurman   United States
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Registered: June 2015
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Member
I have 50 amp with no problems with both (original) AC's but my question
is: what is the "adapter" that is mentioned?

On Tue, Jun 19, 2018 at 9:34 PM, Jon Roche wrote:

> I carry a couple adaptors. So i can plug in about anything. My 30 amp
> to 15 amp cord and my fan came in handy on saturday to verify a 30 amp
> campground outlet was dead.
>
> I also keep one of these:
>
>
> https://www.walmart.com/ip/Power-Gear-3-Wire-Receptacle-
> Tester-50542999/16561511?wmlspartner=wlpa&selectedSellerId=0&adid=
> 22222222228016731164&wl0=&wl1=g&wl2=m&wl3=40873258712&wl4=
> pla-78765756632&wl5=1020086&wl6=&wl7=&wl8=&wl9=pla&wl10=
> 8175035&wl11=online&wl12=16561511&wl13=&veh=sem
>
> Tells me pretty quick
> If there is power or not
>
>
> Let me know if you need anymore assistance or a place
> To park. Just off i-94, st. Cloud, MN exit 171.
> --
> Jon Roche
> 75 palm beach
> St. Cloud, MN
> http://lqqkatjon.blogspot.com/
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
William S. Schurman
box 772806
Steamboat Springs, CO
80477
1978 Palm Beach
TZE168V100258
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Re: [GMCnet] Lost 30A service [message #333755 is a reply to message #333754] Wed, 20 June 2018 15:21 Go to previous messageGo to next message
77Royale   United States
Messages: 461
Registered: June 2014
Location: Mid Michigan
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Senior Member
There are adapters that on one end plug into a 50A outlet, and the other female end take a 30A plug. And again from 30A on one end to a male 15A.

You can find them on Amazon or Walmart for as little as 5 bucks. You can pay a bit more and find them with little lights inside so when you plug it in you know you have power.

These are helpful if you only have a 15A power source. Plug in a heavy extension cord, or directly to the outlet with the use of the adapter. You can still plug in normally, but mostly just to charge batteries. Maybe run one AC for a bit before the cord gets warm.

Also helpful if all you have to plug into is a 50A outlet, and your plug is 30A. Just put the adapter in line. and your good to go. I did this at Elkhart as the 30A plug was already spoken for.



77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson carb and dizzy. Mid Michigan

[Updated on: Wed, 20 June 2018 15:22]

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Re: [GMCnet] Lost 30A service [message #333759 is a reply to message #333755] Wed, 20 June 2018 16:12 Go to previous messageGo to next message
w schurman is currently offline  w schurman   United States
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Registered: June 2015
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OK, I get it, I have a 50 A to 30 A "dog bone" in case the campground only
has 30 amp.

On Wed, Jun 20, 2018 at 2:21 PM, Wayne Rogewski wrote:

> There are adapters that on one end plug into a 50A outlet, and the other
> female end take a 30A plug. And again from 30A on one end to a male 15A.
>
>
> You can find them on Amazon or Walmart for as little as 5 bucks.
>
> These are helpful if you only have a 15A power source. You can still plug
> in normally, but mostly just to charge batteries. Maybe run on AC for a
> bit before the cord gets warm.
>
> Also helpful if all you have to plug into is a 50A outlet, and your plug
> is 30A. Just put the adapter in line. and your good to go. I did this at
> Elkhart as the 30A plug was already spoken for.
>
>
> --
> 77 Royale, Rear Dry Bath. 403, 3.55 Final Drive, Lenzi goodies, Patterson
> carb and dizzy.
> Mid Michigan
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
William S. Schurman
box 772806
Steamboat Springs, CO
80477
1978 Palm Beach
TZE168V100258
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Re: [GMCnet] Lost 30A service [message #333760 is a reply to message #333759] Wed, 20 June 2018 16:46 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
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The dogbone styles work better then the small adaptors. Melted many adaptors and cord ends trying to run the oem a/C's on long extension cords.

Now i have my main A/C that uses almost 1/2 the power the original one did.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: Lost 30A service [message #333762 is a reply to message #333725] Wed, 20 June 2018 19:04 Go to previous messageGo to next message
Deb is currently offline  Deb   Canada
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
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Senior Member
Picked up a new dog one adapter. We're in Chippewa Falls and have access to a 50a outlet. Front air works as does water heater but not rear ac nor any of the outlets. Breaker box shows outlets and the rear ac share the bottom left pair of 20A breakers. Looks like it got fried in the process. Once I'm settled somewhere for a couple of days I will shut off the main breakers, pull those and replace them. Hopefully it's just a matter of that breaker gone when I blew the adapter. Could be that rear ac pulled too much for everything to handle with the front also running.

Deb McWade Logan Lake, BC, CAN GMC Alumnus It's Bigger on the Inside!
Re: [GMCnet] Lost 30A service [message #333765 is a reply to message #333762] Wed, 20 June 2018 19:26 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Location: Americus, GA
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Deb,

Even before you change the circuit breakers, you may want to disconnect
shore power and, if you have one, turn off your inverter. Pull the
breakers cover and tighten every screw in the box. You'll probably find a
lot of them loose; perhaps some loose enough to cause the loss of power
you've experienced. That's a simple preventative maintenance item everyone
should perform periodically. Even home breaker boxes, constantly exposed
to heating and cooling, and using ductile conductors, develop loose
connections. Constantly vibrating on the road makes RV's much more prone
to the malady.

​Ken H.​


On Wed, Jun 20, 2018 at 8:05 PM Deb McWade wrote:

> Picked up a new dog one adapter. We're in Chippewa Falls and have access
> to a 50a outlet. Front air works as does water heater but not rear ac nor
> any
> of the outlets. Breaker box shows outlets and the rear ac share the bottom
> left pair of 20A breakers. Looks like it got fried in the process. Once I'm
> settled somewhere for a couple of days I will shut off the main breakers,
> pull those and replace them. Hopefully it's just a matter of that breaker
> gone when I blew the adapter. Could be that rear ac pulled too much for
> everything to handle with the front also running.
> --
> Deb McWade
> Logan Lake, BC, CAN
> "Li'l Sister"
> '77 Kingsley, 403, EBL EFI;
> TZE167V101404
> It's Bigger on the Inside!
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Lost 30A service [message #333766 is a reply to message #333725] Wed, 20 June 2018 19:37 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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Location: S. Ontario, Canada
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Senior Member
since you said your 30 amp adapter got hot, I would lean towards one of the 50 amp plug pins has lost contact with its internal wire. In a 50 Amp plug there is 2 circuits carrying power and a single Neutral. So 1/2 of your breaker panel is not getting power.

If your 50Amp main plug is a molded construction, (which it will be if it is original), you will not be able to take it apart. You can buy replacement plugs that screw together. Buy a replacement 90 degree plug and look up an electrical contractor in the local town and pay them to put it on properly.

You should be able to get away with one A/C unit unless you find yourself in the southern states without shade in the summer.

Just my guess after 45 years of troubleshooting electronics.


Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Lost 30A service [message #333767 is a reply to message #333725] Wed, 20 June 2018 19:55 Go to previous messageGo to next message
Deb is currently offline  Deb   United States
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
Karma: 2
Senior Member
Uh Oh Oich! OK - smack me and screw my head back on. Put my glasses on (the READING ones) and actually READ the breaker switches - ON is toward the centre of the box, not toward the bottom.
So.... flipped the bottom breakers switches UP and guess what!? Everything is fine. Embarassed So, Although I DID fry the 50 to 30A dog-bone, everything else is fine and runs perfectly on the 50A connector.

I think I'm going to go to bed now and start the day over!


Deb McWade Logan Lake, BC, CAN GMC Alumnus It's Bigger on the Inside!
Re: Lost 30A service [message #333768 is a reply to message #333725] Wed, 20 June 2018 20:35 Go to previous messageGo to next message
RF_Burns is currently offline  RF_Burns   Canada
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First rainy day when you have some time, I'd do what Ken Henderson suggested... unplug the coach, take the front panel off the breaker box and tighten all the connections. I believe I got more than a full turn on each screw when I did mine.

Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.
1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
Re: Lost 30A service [message #333769 is a reply to message #333725] Wed, 20 June 2018 20:35 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Great. Now pick one AC or the other to run on the 30 not both.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: Lost 30A service [message #333791 is a reply to message #333769] Thu, 21 June 2018 08:55 Go to previous messageGo to next message
Deb is currently offline  Deb   United States
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
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JohnL455 wrote on Wed, 20 June 2018 18:35
Great. Now pick one AC or the other to run on the 30 not both.

Thanks. Yes - In future I plan to alternate. I will also make sure I switch the fridge over to the LP before I turn on the ac.


Deb McWade Logan Lake, BC, CAN GMC Alumnus It's Bigger on the Inside!
Re: [GMCnet] Lost 30A service [message #333793 is a reply to message #333765] Thu, 21 June 2018 09:03 Go to previous messageGo to next message
Deb is currently offline  Deb   United States
Messages: 349
Registered: October 2016
Location: Logan Lake, BC
Karma: 2
Senior Member
Ken Henderson wrote on Wed, 20 June 2018 17:26
Deb,

Even before you change the circuit breakers, you may want to disconnect
shore power and, if you have one, turn off your inverter. Pull the
breakers cover and tighten every screw in the box. You'll probably find a
lot of them loose; perhaps some loose enough to cause the loss of power
you've experienced. That's a simple preventative maintenance item everyone
should perform periodically. Even home breaker boxes, constantly exposed
to heating and cooling, and using ductile conductors, develop loose
connections. Constantly vibrating on the road makes RV's much more prone
to the malady.

​Ken H.​




Thank you Ken. On the list of things to do. That's good information that as with all things electrical, I have in limited supply. Much appreciated-both the adivice and the patience Dead for newbie self-inflicted problems. That goes to everyone on this trip so far. Keeping me relatively relaxed amid the confusion.


Deb McWade Logan Lake, BC, CAN GMC Alumnus It's Bigger on the Inside!
Re: [GMCnet] Lost 30A service [message #333950 is a reply to message #333765] Sun, 24 June 2018 20:40 Go to previous messageGo to next message
Richard RV   United States
Messages: 631
Registered: July 2012
Location: Full-timer for 12 years, ...
Karma: -17
Senior Member
Deb,
While you're following Ken's advice it's a good idea to pull the breakers and examine the breakers' connectors/clips and the bus bar. Forty year old breakers can have broken plastic retainer clips or loose metal clips, and bus bars can get eaten by arcing caused by loose connections.

My coach had all of the above problems with the original Coachmen box and breakers. One breaker had gotten so hot that the thermoplastic sealant used over the assembly screw on the back, meant to prevent arcing to the bus bar, had melted.

As a quick and periodic check, check the temperatures of the breakers with an IR thermometer.

Richard

Ken Henderson wrote on Wed, 20 June 2018 20:26
Deb,

Even before you change the circuit breakers, you may want to disconnect
shore power and, if you have one, turn off your inverter. Pull the
breakers cover and tighten every screw in the box. You'll probably find a
lot of them loose; perhaps some loose enough to cause the loss of power
you've experienced. That's a simple preventative maintenance item everyone
should perform periodically. Even home breaker boxes, constantly exposed
to heating and cooling, and using ductile conductors, develop loose
connections. Constantly vibrating on the road makes RV's much more prone
to the malady.

​Ken H.​




'77 Birchaven TZE...777; '76 Palm Beach under construction; ‘76 Edgemont waiting its turn
Re: [GMCnet] Lost 30A service [message #333953 is a reply to message #333950] Sun, 24 June 2018 21:38 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Excellent point, Richard. I guess I forgot all that since I replaced my
box when I gutted the coach in '98. Even I should recheck it now.

​Ken H.




On Sun, Jun 24, 2018 at 9:52 PM Richard wrote:

> Deb,
> While you're following Ken's advice it's a good idea to pull the breakers
> and examine the breakers' connectors/clips and the bus bar. Forty year old
> breakers can have broken plastic retainer clips or loose metal clips, and
> bus bars can get eaten by arcing caused by loose connections.
>
> My coach had all of the above problems with the original Coachmen box and
> breakers. One breaker had gotten so hot that the thermoplastic sealant used
> over the assembly screw on the back, meant to prevent arcing to the bus
> bar, had melted.
>
> As a quick and periodic check, check the temperatures of the breakers with
> an IR thermometer.
>
> Richard
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Lost 30A service [message #333960 is a reply to message #333953] Sun, 24 June 2018 23:26 Go to previous message
Richard RV   United States
Messages: 631
Registered: July 2012
Location: Full-timer for 12 years, ...
Karma: -17
Senior Member
Ken,
I stumbled upon the problem...thankfully! I was in Phoenix one July and touched my shore power cord to check it's temperature. Hot! IR thermometer showed 160°. It was in the sun, but... So I started working backwards from the campground pedestal and checking all the temperatures. Circuit breaker in the coach was 158°. Uh oh. That's when I opened up the breaker box, found the broken circuit breaker retaining clip, melted thermoplastic and saw the bus bar eroded by electrical arcing.

I was chatting with the lady behind the campground counter and told her of my electrical issues. She gave me a tip which hasn't occurred to me. Don't put the more heavily used circuit breakers next to each other and on the outside. Idea being to keep the heat from transferring between breakers. Probably not a big issue in normal circumstances, but still a good rule of thumb when installing breakers.

Richard


'77 Birchaven TZE...777; '76 Palm Beach under construction; ‘76 Edgemont waiting its turn

[Updated on: Sun, 24 June 2018 23:28]

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