Go Back   iRV2 Forums > iRV2.com COMMUNITY FORUMS > iRV2.com General Discussion
Click Here to Login
Join iRV2 Today

Mission Statement: Supporting thoughtful exchange of knowledge, values and experience among RV enthusiasts.
Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on iRV2
 
Thread Tools Search this Thread Display Modes
 
Old 10-21-2014, 11:39 AM   #1
Member
 
Join Date: Jun 2010
Posts: 66
Keep tripping main breaker RANDOMLY... sometimes after a week!

I feel a long confusing post coming... please read the whole thing before replying!

1979 Shasta Class-C

We're full timers and not having power is very, very bad!!

Since we've bought it we've had problems with the main breaker tripping randomly.

Doesn't matter if you have anything on or even plugged in; seems to just be at total random.

Sometimes it'll go a week without issue, sometimes it'll do it once a day, and sometimes it'll pop every hour!

We've replaced the breaker (P20) with a new one hoping it was just weak. Wasn't easy to find! No change.

There is only one other breaker and that's strictly for the air conditioning unit.

I've removed all the 12v fuses from the converter to isolate the system and it still happens.

I've disconnected the fridge at the back; both 12v and AC.

Nothing is plugged into any outlet.

We do not use the water in the camper so the water heater is not used.

We don't have LP (leaky tank) so the furnace is not used. Did work fine before the LP was depleted.

Everything else functions fine. Fans, lights, all outlets, etc.

Disconnected the house battery in case it was shorted (though it's 6 months old); no change.

Also does not seem to be temperature related. Happened in the summer, happened the other night when it was 30 out. Morning, noon, night... doesn't change.

At this point everything points to either the DC converter itself or a bad connection somewhere in the AC lines that's causing resistance and building up heat till that breaker pops.

Once the breaker has tripped it cannot be reset till you wait around 10 minutes. If you try and reset it before then it trips immediately. Also points to something getting hot.

I do see the main line feed to the plate the breakers mount to is melted at the end though that could be old.

I put a good fan on the converter insides hoping that was the problem... also not the case.

Problem is... I have no idea where to start.

Aside from gutting the damn thing, how the heck do I troubleshoot this further???





__________________

__________________
Full timing in a 1979 Dodge Sportsman Shasta 22' - 440 power in a little package!
aaron7 is offline   Reply With Quote
Join the #1 RV Forum Today - It's Totally Free!

iRV2.com RV Community - Are you about to start a new improvement on your RV or need some help with some maintenance? Do you need advice on what products to buy? Or maybe you can give others some advice? No matter where you fit in you'll find that iRV2 is a great community to join. Best of all it's totally FREE!

You are currently viewing our boards as a guest so you have limited access to our community. Please take the time to register and you will gain a lot of great new features including; the ability to participate in discussions, network with other RV owners, see fewer ads, upload photographs, create an RV blog, send private messages and so much, much more!

Old 10-21-2014, 11:56 AM   #2
Moderator Emeritus
 
Gary RVRoamer's Avatar


 
Join Date: Jan 2000
Location: Silver Springs, FL. USA
Posts: 18,066
You can stop fiddling with the fuses and battery 12v stuff because that can't trip the 120v/20A breaker. Even a direct short there would not cause a trip because your converter cannot draw anywhere near enough current to trip that breaker. I suppose the converter itself could be internally shorted (intermittently) though. It is probably fed via that breaker if the only other one is for the a/c.

More likely, though, you have a tiny short in the 120v wiring downstream from that breaker. A stray strand of wire that occasionally touches as it heats/cools or a brief air current moves it, or some of that dust I see in the pictures crosses two wires and a spark jumps. You might try vacuuming all that dust & dirt away for starters (do it with shore power disconnected, just to be safe).

Are you sure the water heater electric mode (if it has one) is turned off? If not, it is heating water whether you actually use any or not.
__________________

__________________
Gary Brinck
Former owner of 2004 American Tradition
Home is in the Ocala Nat'l Forest near Ocala, FL
Summers in Black Mountain, NC
Gary RVRoamer is offline   Reply With Quote
Old 10-21-2014, 12:08 PM   #3
Senior Member
 
Skip426's Avatar


 
Join Date: Apr 2011
Location: Powell River, B.C.
Posts: 14,970
I'm thinking your next step would be to hook an independent battery charger to the coach battery, so you have 12v lights etc. , and disconnect the 110v supply from the converter/charger coil.
Without being there with a volt meter, to test 110v power flow, best guess for place to disconnect would be the white wiring cap in the second to last picture, next to the coil.

Of course , as Gary says , best time to do that would be with shore power disconnected.
__________________
99DSDP 3884, Freightliner, XC, CAT 3126B, 300 HP /ALLISON 3060
2000 Caravan toad, Remco & Blue Ox.
Skip426 is offline   Reply With Quote
Old 10-21-2014, 12:21 PM   #4
Member
 
Join Date: Jun 2010
Posts: 66
Yes I understand it's very dusty! That's only recent due to the fan I put on top of it thinking it was a heat issue. I'll be sure to vacuum it all out!

The water heater is about 6 years old but I do believe it's LP only. If it also has electrical power I don't believe it's connected.

I do believe you are correct in thinking it's in one of the AC lines though. But since there's only one breaker for EVERYTHING AC I'm not sure how to go about tracing lines!
__________________
Full timing in a 1979 Dodge Sportsman Shasta 22' - 440 power in a little package!
aaron7 is offline   Reply With Quote
Old 10-21-2014, 01:59 PM   #5
Senior Member
 
Join Date: Sep 2014
Location: Newcastle West, Ireland
Posts: 392
Quote:
Originally Posted by aaron7 View Post
Yes I understand it's very dusty! That's only recent due to the fan I put on top of it thinking it was a heat issue. I'll be sure to vacuum it all out!

The water heater is about 6 years old but I do believe it's LP only. If it also has electrical power I don't believe it's connected.

I do believe you are correct in thinking it's in one of the AC lines though. But since there's only one breaker for EVERYTHING AC I'm not sure how to go about tracing lines!
Change the 30 amp breaker that keeps tripping, they too get old and tired, unable to keep up.
__________________
'98 Southwind 34L, too many cameras, old hat, young heart.
May the light be with you.
Mentor is offline   Reply With Quote
Old 10-21-2014, 02:33 PM   #6
Registered User
 
Join Date: Sep 2014
Posts: 2,308
After looking up your breaker ( P120GF ) I would do the following just to eliminate the breaker itself.
Disconnect the output from the breaker and hook it up to something like a small heater. If the heater runs for ever than you know it's not the breaker.
If it is the breaker it looks like it might be cheaper to put in a new breaker box and breaker.
You could go the other route. Totally bypass the original breaker. Wire in a separate 20 amp breaker and see if the wiring in the trailer causes it to trip.
Be careful.
__________________
okcnewbie is offline   Reply With Quote
Old 10-21-2014, 02:35 PM   #7
Registered User
 
Join Date: Sep 2014
Posts: 2,308
I don't think it can be converter but if you find you need an old Magnetek 6300 you could PM me and we can find one really cheap.
__________________
okcnewbie is offline   Reply With Quote
Old 10-21-2014, 03:59 PM   #8
Senior Member
 
George Schweikle's Avatar
 
Join Date: Apr 2004
Posts: 2,197
aaron7, I used to work in circuit breaker and panelboard design and remember just a little of that long ago activity.

Like most RV's, you have a circuit breaker designed for residential use. These trip for two reasons; SHORT CIRCUIT trips magnetically, quickly, and THERMAL trips when a bimetal strip becomes hot from excess current and trips the breaker mechanism (sometimes this takes some time, depending on the load). Your reset sequence indicates a thermal (non-short circuit) overload, and the continued problem with a new breaker indicates the problem isn't the breaker itself.

Somewhere there is an intermittent load that is beyond the capacity of the breaker (what amperage is the breaker?). What is happening is that the load isn't a short circuit, rather something just beyond the current carrying capacity of the breaker. It finally trips, then the current is off until you can get the breaker to reset, then the cycle starts again Since you have turned off all loads in the coach the problem is elsewhere and could be the "melted" connection to the breaker itself. Can you show this in a picture?

You mentioned there are only two breakers, and these are likely from one of the major manufacturers (Square D, GE, Siemens, ITE, etc.) and converter manufacturers use these in their combination products. It may be that you can replace the section of your converter that contains your breaker mount and connections, although the company that made the breaker and mount may be out of business which is why you had such a hard time finding a breaker.

Whatever the mysterious excess load on the breaker, it may be right at the thermal calibration limit, and this setting may be varying just enough to change the duration of trip times. The thermal calibration is actually a range or window defined by Underwriters Laboratories. Again, seeing a picture of the breaker(s), and connections may reveal something.

Quote:
Originally Posted by aaron7 View Post
...Sometimes it'll go a week without issue, sometimes it'll do it once a day, and sometimes it'll pop every hour!.



We've replaced the breaker (P20) with a new one hoping it was just weak. Wasn't easy to find! No change....

Once the breaker has tripped it cannot be reset till you wait around 10 minutes. If you try and reset it before then it trips immediately. Also points to something getting hot.

I do see the main line feed to the plate the breakers mount to is melted at the end though that could be old...
__________________
George Schweikle Lexington, KY
1999 Safari TREK 2830, FMCA 190830, Safari International chapter
1995 Safari TREK 2630, 1983 Winnebago Chieftain, 1976 Midas Mini
George Schweikle is online now   Reply With Quote
Old 10-21-2014, 04:14 PM   #9
Senior Member
 
RW8804's Avatar
 
Entegra Owners Club
Join Date: May 2014
Location: Thornhill, Ontario
Posts: 410
Send a message via Skype™ to RW8804
Have you tested that you are getting clean power from the post?
__________________
Robert and Louise
Thornhill, Ontario
2014 Anthem 44SL and 2014 Ford Fusion Hybrid
RW8804 is offline   Reply With Quote
Old 10-21-2014, 05:14 PM   #10
Senior Member
 
wa8yxm's Avatar
 
Damon Owners Club
Workhorse Chassis Owner
Join Date: Mar 2009
Posts: 22,790
YOu said you used a 20 amp breaker but even with everything off it trips (or is the A/C on)

First, is your rig a 20 or 30 amp (Compare the power plug) if it's a 30 then the main breaker should be 30 amps.

Second: the A/C... When was the last time you did any cleaning on the coils. Epically the condenser.. On my coach (50 amp) one of the A/C's (13.5 amp normal draw) started popping the 20 amp branch breaker.. Turns out it was Seriously overdue for some tender loving cleaning.

I took the business end of the 150PSI huffer-puffer up there (Air compressor hose with jet nozzle) and blew the CR** out and suddenly the draw is back down to 13.5 (from 21 when the breaker tripped by measurement).

And as for that power converter/charger.. You should consider an upgrade. That is a very old unit, and the new ones are lighter, more efficient, Quieter and treat the battery better as well. Just so you know

I like Progressive Dynamics Intella-power units with charge wizard
__________________
Home is where I park it!
wa8yxm is offline   Reply With Quote
Old 10-22-2014, 04:16 AM   #11
Senior Member
 
spritz's Avatar


 
Vintage RV Owners Club
Fleetwood Owners Club
Join Date: Mar 2013
Location: c above
Posts: 4,947
Mine does the same thing but it only happens in the mornings with nothing on. Its 30 amp brand new outlet on the S&B (dedicated) Some times it just trips the main on the MH and sometimes it blows the breaker in the S&B Your not alone.
Thanks I'll watch for comments.
Thanks,Tim
__________________
1982 Pace Arrow 30ft.
KarKaddy SS, Toad: 1999 Deville Concours
Lilly and Rubie Our 4 legged Kids & Tim & Joe
spritz is offline   Reply With Quote
Old 10-22-2014, 10:05 AM   #12
Senior Member
 
Join Date: Feb 2010
Posts: 4,492
Measure voltages...

Or...

Disconnect all load wires and wait...

Connect them one at a time and measure voltages to see if and how they drop voltage.

Only connect one at a time.

If one drops more than rest see why.

If no issues then hook up all but one and rotate the non connected until it faults.

Or...

Get a clamp on ammeter and measure current draw on every wire and perform normal troubleshooting and repair.
__________________
Tony & Lori
1989 Country Coach Savannah SE
TQ60 is offline   Reply With Quote
Old 10-22-2014, 11:41 AM   #13
Senior Member
 
wa8yxm's Avatar
 
Damon Owners Club
Workhorse Chassis Owner
Join Date: Mar 2009
Posts: 22,790
Quote:
Originally Posted by okcnewbie View Post
I don't think it can be converter but if you find you need an old Magnetek 6300 you could PM me and we can find one really cheap.
What are those worth now days about 2 per pound?
__________________
Home is where I park it!
wa8yxm is offline   Reply With Quote
Old 10-22-2014, 05:27 PM   #14
Senior Member
 
Join Date: Nov 2012
Location: Keeseville ny
Posts: 361
I think it is your 5 th picture it shows the breaker on the bottom of it. Behind the breaker is 2 wire lugs. The lower one looks like it got hot and melted the insulation and maybe some of the wire. The wires are black in color.
__________________

__________________
cwit is online now   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Main Circuit Breaker fail.. Hooligan MH-General Discussions & Problems 7 09-09-2014 08:24 PM
6.5KW Onan LP generator breaker keeping tripping Geneandea Class A Motorhome Discussions 9 09-03-2014 02:10 PM
2003 Journey second a/c compressor trips breaker Kelm130 Winnebago Industries Owner's Forum 10 08-22-2014 07:07 AM
12VDC 30A circuit breaker tripping TexasSkunk Tiffin Motorhomes Owners Forum 2 08-18-2014 01:57 PM
Main Power Dead Diesel Diva Entegra Owner's Forum 26 07-21-2014 01:33 PM

» Virginia Campgrounds

Reviews provided by


Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 06:48 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.