FIRE! 50 - 80amp breaker upgrade. Beware

[savagkd]

Heads up to all who have done this mod. 6AWG was not enough in my case.

We upgraded to the 80amp breaker last fall for the same reason as most, slides stopping. All was good. Until now.

We just spent two weeks slowly migrating from summer in Idaho to winter in Texas. After an overnight stay with electric only hookup, we closed the slides, hooked up, forgot something so had to reopen the slides and close them again, then headed for the dump station in the park. All this in about 20 minutes. While dumping, something smelled like someone just blew out a candle. Decided to go back to the campsite for a better look. When I opened the passthrough, there was smoke coming through the top gap between passthrough and front compartment. Threw the battery and solar disconnects, grabbed the extinguisher from the truck, opened the front compartment and hosed the fire.

The factory 6AWG wire from breaker to hydraulic pump had melted the insulation and caught fire.



My solution was to replace all of the 6AWG in the entire circuit with 2AWG.

[WhittleBurner]

That could have been a total loss , good thing you have a good nose and didn't ignore the smell. A lesson for others to not ignore an odor that even smells slighly electrical.

[Hoopy Frood]

Makes you think they knew what they were doing when they put that 60 amp fuse in there.

[savagkd]

Next project is installing fire extinguishers in both propane compartments as they cannot be locked. All of my extinguishers in the 5er were inside doors, locked for travel, and the keys were in the truck. Never thought that would be a problem. Thankfully, the one in the truck was handy.

[traveldawg]

I'm glad you found the problem in time and before anymore damage.

I was thinking about this. First, it seems 6 gauge wire should be OK given the short distance from the breaker to the pump. Someone should actually measure the current draw on that pump, but I don't think it draws 80 amps, or even 60.

Anyhow, it doesn't look like the problem started on the wire from the big breakers to the pump. It looks to me like the 6 gauge wire from that bottom breaker goes behind all the bundles of wire and then up to the pump. And it seems to be in good shape.

It looks like the hydraulic hoses took a beating. I hope them are OK and don't need patching or replacing.

It seems that the primary 12v wire maybe got hot. Or something in that bundle of wires that disappears into the belly.

Whatever - you were there, you should know better than me. Time to drop the corroplast to the underbelly to look things over. Generally when wire get hot to the point of melting it is from drawing enough current for a long enough time to get things heated but not so much as to trip a breaker or blow a fuse.

[xrated]

I'm glad you found the problem in time and before anymore damage.

I was thinking about this. First, it seems 6 gauge wire should be OK given the short distance from the breaker to the pump. Someone should actually measure the current draw on that pump, but I don't think it draws 80 amps, or even 60.

Anyhow, it doesn't look like the problem started on the wire from the big breakers to the pump. It looks to me like the 6 gauge wire from that bottom breaker goes behind all the bundles of wire and then up to the pump. And it seems to be in good shape.

It looks like the hydraulic hoses took a beating. I hope them are OK and don't need patching or replacing.

It seems that the primary 12v wire maybe got hot. Or something in that bundle of wires that disappears into the belly.

Whatever - you were there, you should know better than me. Time to drop the corroplast to the underbelly to look things over. Generally when wire get hot to the point of melting it is from drawing enough current for a long enough time to get things heated but not so much as to trip a breaker or blow a fuse.

I have measured mine several times over a period of time with a clamp on amp meter. It's always right at 70 amps....+/- an amp or two. I replaced the 50A breaker in mine (2018 model) with an 80A and I also doubled the wiring......twin 6ga wires in parallel throughout that circuit.....including the cable that goes to ground/frame and then back to the battery.

[Hoopy Frood]

I put an clamp-on amp meter on our hydraulic pump, and it pulled 65 amps immediately, but dropped down to 60 amps while running the slides out.

[xrated]

I put an clamp-on amp meter on our hydraulic pump, and it pulled 65 amps immediately, but dropped down to 60 amps while running the slides out.

Next time you decide to check it out, try taking a reading when you are raising or lowering the landing gear. Mine actually pulled slightly more when retracting the landing gear, than when extending it. I would have thought it would be just the opposite if there was any difference.....you know, overcoming gravity vs. lifting against gravity.

[Hoopy Frood]

I wonder if you don't have a more powerful motor since that trailer is quite a bit heavier than ours? Hence, more current draw. But I will try that when we get home in a couple weeks.

[savagkd]

I'm glad you found the problem in time and before anymore damage.

I was thinking about this. First, it seems 6 gauge wire should be OK given the short distance from the breaker to the pump. Someone should actually measure the current draw on that pump, but I don't think it draws 80 amps, or even 60.

Anyhow, it doesn't look like the problem started on the wire from the big breakers to the pump. It looks to me like the 6 gauge wire from that bottom breaker goes behind all the bundles of wire and then up to the pump. And it seems to be in good shape.

It looks like the hydraulic hoses took a beating. I hope them are OK and don't need patching or replacing.

It seems that the primary 12v wire maybe got hot. Or something in that bundle of wires that disappears into the belly.

Whatever - you were there, you should know better than me. Time to drop the corroplast to the underbelly to look things over. Generally when wire get hot to the point of melting it is from drawing enough current for a long enough time to get things heated but not so much as to trip a breaker or blow a fuse.

Thanks for the reply traveldawg.

Sorry, the picture is not great and was snapped in a hurry right after. The 6 gage from the breaker was the source. There was about 4 inches behind the bundle that was charcoal. The rest of the damage was melted wire loom and insulation. I was able to pull a good foot of the bundles out of the belly, no damage there. The hydraulic lines did blister a bit, I'll keep an eye on them.