Here's the story. I had a friend ask me to come over and look at why his battery was not charging. He has a 2012 model travel trailer. He was plugged into shore power at his home so I just popped off the battery cables and put the meter on them and it showed nothing. I told him his converter was not charging and he likely needed a new one. He buys one and changes it out and we look again at the battery cable charging output and voila, he has 14 volts. NOW he says he also changed out the circuit breakers on the tongue and he now thinks that was the problem and not the converter. I explained that the battery cables came right from the converter and the current doesn't pass through those breakers to charge the battery. He says I'm wrong. AM I??

Most likely answer, yes.Plug in the old converter and test the 12v output.

He is probably correct that there is a circuit breaker. Best would have been a voltage check right at the converter. However since power was restored with a new converter the breaker could have had an intermittent fault. And now it is he said she said because you did not observe the work. And we still don't know exactly what was done during the swap or what breakers were replaced.Otherwise it is on him for agreeing with you on the diagnosis.Offer to buy the beer next trip...

Easy enough to plug in the old converter and see what happens.Your friend is immensely ungrateful either way though..

As said "plug in the old converter and test the 12v output. "

Some friend! No matter the outcome, be sure to let him know that asking for your help in the future will be a non-starter!

No good deed goes unpunished | Good Sam Community

ken56
Explorer
Jan 30, 2022
philh wrote:
Thank you for the post and all the responses, I learned something today.

Me too actually. That is why I posted this. Most people do not understand RV electrical systems so any light that can be shed upon this subject is welcome and helpful. The wisdom and knowledge that this group has is an invaluable resource and I thank all who responded also.
philh
Explorer II
Jan 29, 2022
Thank you for the post and all the responses, I learned something today.
Boon_Docker
Explorer III
Jan 28, 2022
Grit dog wrote:
Gdetrailer wrote:
ken56 wrote:
Alright people. I posted this for education purposes and not to bash my friend, and yes we are still friends. In order for me to answer my own question I will have to go over and look at the wiring again to see if they pass through the circuit breakers on the tongue. I could very well have been wrong so if this can be used by others to help them understand things then great.

There should be a small metal cased autoreseting breaker mounted close to the battery(ies) on the tongue of the trailer.

Should look like this..

That is basically a "catastrophe" breaker in case the wiring to the converter/fuse panel were to develop a short circuit. Basically there to protect you from ending up setting your rig on fire in the event the wire shorts to ground.

Manufacturers must include a fuse or breaker within 18" of the battery.

These are typically mounted to the A frame on the inside and may be under the battery tray.

They are open to weather and are not really designed for or sealed and over time suffer weather related damage..

The breaker should auto reset after any over current event provided the high current draw is removed and or voltage is removed from the breaker.

Well ya learn something new every day. Thanks for explaining.
Now wonder why I haven't seen this on my last 3 campers? (It makes sense, btw) I've been all over those campers and like to think I'm fairly observant. Actually replaced the + lead from battery to converter in one Arctic Fox and there was not shtf (sht hit s the fan) breaker.

Mine is on the negative cable on my last two trailers.
MFL
Nomad II
Jan 28, 2022
Those breakers are most common with a heavy slide, or heavy lift, such as FW landing gear, or TT with heavy tongue wt/electric jack. In many cases, they are only 3' from battery pos post, but just on inside wall of pass through.

Grit dog...your TH with heavy tongue, may have a similar breaker for the jack, and a second one for a large slide, if you have one. That saying..."old dogs can't learn new tricks" is not true.

If OP had mentioned right away, about the intermittent slide operation, that gives a strong hint of a faulty/dying resetting breaker.

Jerry
Grit_dog
Navigator
Jan 28, 2022
Gdetrailer wrote:
ken56 wrote:
Alright people. I posted this for education purposes and not to bash my friend, and yes we are still friends. In order for me to answer my own question I will have to go over and look at the wiring again to see if they pass through the circuit breakers on the tongue. I could very well have been wrong so if this can be used by others to help them understand things then great.

There should be a small metal cased autoreseting breaker mounted close to the battery(ies) on the tongue of the trailer.

Should look like this..

That is basically a "catastrophe" breaker in case the wiring to the converter/fuse panel were to develop a short circuit. Basically there to protect you from ending up setting your rig on fire in the event the wire shorts to ground.

Manufacturers must include a fuse or breaker within 18" of the battery.

These are typically mounted to the A frame on the inside and may be under the battery tray.

They are open to weather and are not really designed for or sealed and over time suffer weather related damage..

The breaker should auto reset after any over current event provided the high current draw is removed and or voltage is removed from the breaker.

Well ya learn something new every day. Thanks for explaining.
Now wonder why I haven't seen this on my last 3 campers? (It makes sense, btw) I've been all over those campers and like to think I'm fairly observant. Actually replaced the + lead from battery to converter in one Arctic Fox and there was not shtf (sht hit s the fan) breaker.
2112
Explorer II
Jan 28, 2022
That's how most of us learn.

before he replaced the converter and breakers his slides would work intermittently
This indicates a loose connection. Could have been the threaded post on the weathered breaker.
ken56
Explorer
Jan 28, 2022
Thanks 2112 for the response. It never crossed my mind to check the breakers like that so now I have learned not to be so hasty and assume it's the converter. I read so many posts here on 'the lights aren't working right' or the 'slides aren't working right' that I hope this enlightens a few other folks like me as to the simple things we overlook and go right to the complicated fixes...especially in all things electrical. 12 volt RV systems seem to be one of the most misunderstood issues here.

His breakers were very weathered and likely failed/weak because before he replaced the converter and breakers his slides would work intermittently, really weird and a classic malady. I hope this helped others understand things better.
2112
Explorer II
Jan 28, 2022
The question I posed was does the converter current to charge the battery pass through any of those breakers on its way to the battery?
If there is only 1 positive battery cable coming off of the battery, the answer is yes.

My last TT, A Keystone Outback, the breaker Gdtrailer indicated was located behind a false wall inside the front passthrough, not outside on the tongue.

My previous TT was a Sportsmen, and it was located on the tongue, and it did fail due to whether exposure.
ken56
Explorer
Jan 27, 2022
Gdetrailer wrote:
ken56 wrote:
Alright people. I posted this for education purposes and not to bash my friend, and yes we are still friends. In order for me to answer my own question I will have to go over and look at the wiring again to see if they pass through the circuit breakers on the tongue. I could very well have been wrong so if this can be used by others to help them understand things then great.

There should be a small metal cased autoreseting breaker mounted close to the battery(ies) on the tongue of the trailer.

Should look like this..

That is basically a "catastrophe" breaker in case the wiring to the converter/fuse panel were to develop a short circuit. Basically there to protect you from ending up setting your rig on fire in the event the wire shorts to ground.

Manufacturers must include a fuse or breaker within 18" of the battery.

These are typically mounted to the A frame on the inside and may be under the battery tray.

They are open to weather and are not really designed for or sealed and over time suffer weather related damage..

The breaker should auto reset after any over current event provided the high current draw is removed and or voltage is removed from the breaker.

Thank you and yes, that is what my friend also replaced when he did the new converter. It is correct that I did not participate in his work changing out the converter and breakers so I do not know exactly what he did...I assumed it was only the replacing of the converter an breakers...that's all. The question I posed was does the converter current to charge the battery pass through any of those breakers on its way to the battery? If it does then it would/could stop the charging current to the battery and it may not have been a bad converter.
Gdetrailer
Explorer III
Jan 27, 2022
ken56 wrote:
Alright people. I posted this for education purposes and not to bash my friend, and yes we are still friends. In order for me to answer my own question I will have to go over and look at the wiring again to see if they pass through the circuit breakers on the tongue. I could very well have been wrong so if this can be used by others to help them understand things then great.

There should be a small metal cased autoreseting breaker mounted close to the battery(ies) on the tongue of the trailer.

Should look like this..

That is basically a "catastrophe" breaker in case the wiring to the converter/fuse panel were to develop a short circuit. Basically there to protect you from ending up setting your rig on fire in the event the wire shorts to ground.

Manufacturers must include a fuse or breaker within 18" of the battery.

These are typically mounted to the A frame on the inside and may be under the battery tray.

They are open to weather and are not really designed for or sealed and over time suffer weather related damage..

The breaker should auto reset after any over current event provided the high current draw is removed and or voltage is removed from the breaker.