12 volt isolation solenoid trouble shooting

[rgolding]

So driving across I-70 over Memorial Day Holiday Weekend, I got in to a big rain storm. Pulled in to rest area twice as we were driving east with the storm and kept catching up to it. Finally headed south and when we got to our destination, we had no 12 volt power and the main power cable from the battery was jumping.

I resolved the battery cable jumping by shutting the 12 volt power off. I have a positive wire battery cut off switch. Still had trailer lights when hooked to the vehicle and crippled home. I'm guessing with no brakes, but we have a good size truck and able to stop with out much trouble.

Spent today trouble shooting. Battery was first thing questioned and it tested good. I finally isolated the problem to an "isolation solenoid" on front of trailer frame. No matter what fuse I pull or even after disconnecting the entire battery panel, I still get this sound of a circuit breaker tripping and then quickly resetting and tripping again.

No clue of what this is actually called and I'm having trouble even finding a name or number on it. Battery positive cable goes to it, hooking to one post and then continues on back out, hooked to the other post. There is NO ground wire, but it might ground to frame as it is held on with 2 machine screws AND I think the power wire coming out of it connects into a junction box with the 7 pin plug from the truck, before going on to the power distribution panel in the cabin. Any clues?

2010 Dutchmen 25C-GS

I appreciate your time.

[rgolding]

Sorry, double post

[rgolding]

Trying to answer my own questions -

"So I've still got questions about the "Shortstop 12v s34 40A" circuit breaker." _- Its a circuit breaker, not a solenoid, power flows both directions as long as its under 40 amps and it opens restricting power flow above 40 amps, not closed until power is applied to it.

"Does it allow current to flow both directions?" - Yes, as long as it is below 40 amps

Or is it just one directional? Nope, power is only on one side, the stud marked "Bat" for Battery and the side marked "Aux" will be isolate if over 40 amps.

"What is the reason they are in the lines other than protection?" - The only reason.

Just as a circuit protector or to prevent back flow of electricity? - Circuit Protection for below 40 amps.

"Does it allow trailer battery to be charged by the towing vehicle? That has always been my assumption, but now a reason for more investigation." - At this time I'd say yes, as long as it doesn't exceed 40 amps.

My problem was thinking the solenoid theory instead a simple breaker. Took some serious conversations to get this thought pattern out of my head. I think the 2 gallons of gasoline and the 60 lbs. of propane next to the pulsating battery cable was what was clouding my thoughts. And having no problems and then driving though a day of big rain storms and instantly having problems didn't help. You've always got to go back to the basics and look for the simple answer.

Thanks for reading and answering. On the road again and camping tomorrow night. LIFE IS GOOD

[rgolding]

Thank you for the replies and you were both right on the money. I saw your replies after I had got the problem fixed. I suspected a short, but I did not know about the second breaker. Please read below.

The plot thickens -

I really thought it was the thing I was calling a "12 volt single isolator rectifier" and that's what I went to bed thinking last night. My objective this morning was to remove the circuit unit from the circuit by putting the 12 volt battery positive wires on the same post. Turned power on, same thunk. That's it, I'm done.

Off to Bourbon RV in Bourbon, Missouri on I-44 for some help. At first they were puzzled, but what "Steve the Technician" knew that I didn't is that there were two of these circuit breakers. I was looking at the wrong one. They are very close to each other on either side of the front frame. The second one is hidden in a receptacle box on the back side of the same frame member. With tripping and resetting it was the source of the "thunk" and hot from being exercised. Determination was a short between there and the panel. He began feeling along the under skirt and found a place where positive wire was pinched between frame and plywood floor. Slit under skirt, pride wire out from between frame and plywood floor, repaired worn spot by insulating with tape, and replaced "thunking" breaker with new one, because it had been exercised so much, and I kept old one as a spare, plus a secondary new one. Seems to have been a problem waiting to happen since construction in late 2009 or early 2010 and finally wore through after about 15,000 miles. Not related to rain storm or any thing else, just time and wear and eventually a short against the steel frame.

So I've still got questions about the "Shortstop 12v s34 40A" circuit breaker.

Does it allow current to flow both directions?

Or is it just one directional?

What is the reason they are in the lines other than protection?

Just as a circuit protector or to prevent back flow of electricity?

Does it allow trailer battery to be charged by the towing vehicle? That has always been my assumption, but now a reason for more investigation.

Thoughts or opinions?

By the way, did I say the guys and gals at Bourbon RV in Bourbon, Mo. on I-44 are good? You bet they are!

[Gdetrailer]

What you actually are describing is a circuit breaker.

should look like the one in the link below.

12V circuit breaker

That "clicking" sound is because you have a short somewhere on the 12V wire. This wire feeds the fuse panel/converter box.

There should also be another wire which goes to your emergency break away switch (which is supposed to go to the positive of the battery).

The fuse panel/converter should also have a fuse on the other end of this wire. That fuse may be blown also if the wire is damaged.

If panel fuse is not blown then you might have a blown converter (this can happen if you accidentally connect the battery up backwards). Are you SURE that you have connected the battery correctly?

You will need to find the short, this may require replacing the wire back to the converter.. or replacing a blown converter.

[BBuchorn]

What I believe you are talking about is actually a circuit breaker in the 12 volt main. go back again and look at the wiring.I bet you have a cable that has gone to ground somewhere. my T/T has one as well. Trace the positive cable back to your invertor looking for any possibility of a short. Don't leave it hooked up because if uncorrected you could cause a fire. The breaker is doing its job.
Good luck finding the short.
Good Luck And Good Camping!
BBuchorn

[rgolding]

Might be called a "12 volt single isolator recitifer".