Electrical Fire

[ClimberRob]

Just had an electrical fire in my 2006 Grandby. Thankfully had just parked, climbed in the camper and popped the top when smoke started billowing out of the cabinets from just about every opening. Main power switch was OFF. Took me over a minute to disconnect the negative battery cable. Thankfully, I was able to stop the fire with minimal effort; ie: no extinguisher needed.

It appears that the ground/negative wire running from the first grounding block/terminal (next to the water pump) to the back of the IOTA fuse/power center completely melted its insulation off along the entire run. This wire was loose at the connection to the back of the IOTA terminal. I assume that this loose connection caused a spike in resistance and the wire heated beyond its capacity.

I have now disassembled as much as I can to access the full wire run. This wire is poorly spliced in several places, some splices include a connection to 2 or 3 other ground wires along the run. In addition, this wire is severely undersized. It is a 14 AWG wire supplying the negative connection to everything running off of the fuse block.

My plan is to replace the entire run with a doubled 12 AWG marine-grade wire and re-wire all of the individual splices with their own ground wire running to a new terminal I will install behind the IOTA fuse center. I'm hoping that there aren't any unseen issues with other wires. So far it seems like all of the other wires insulation remained intact during all of this.

This camper smells horrible, and the wire melted through the non-pressure water-tank fill hose, so I'll have to replace that, as well.

It could have been worse...

 

[photohc]

I'm curious, was the IOTA converter turned on with power from shore power? When you say the main was turned off, are speaking of the DC main (push/pull toggle switch) or the AC main breaker?

 

[Old Crow]

The Iota converter was the first thing that jumped into my mind but in this case I believe we're reading about the Iota IDP-30 Distribution Panel used on many FWC campers (except shell models) up to 2012. The IDP-30 contains the AC and DC distribution panels and is also referred to as a power center or load center. Those campers also typically have an Iota DLS-30 AC-to-DC battery charger connected to one of the circuit breakers on the AC side of the IDP-30 so those have two Iotas.

I remember having a hard time finding a manual for the IDP-30 and then saw Happyjax's Well lookie what I found post with it in PDF form. It's interesting to see it has two black wires coming out the back for the 12-volt input connections and then separate red and blue wires, each marked with the fuse position, coming out of the back for the fuse panel's output connections. We can also see the IDP-30's DC ground connection in Figure F.

IDP-30 owners may also be interested in wuck's warts-and-all schematic of his 04 Hawk.

PS-- Glad to see you saved the camper and your truck, ClimberRob! I wish I had the electrical knowledge to be more helpful. Offhand, I don't understand why a fuse wouldn't have blown and I don't get what was drawing the power.
.

 

[Beach]

I have entertained the idea of installing a marine type battery switch(main cut off)for a while now. After reading this I'll get off the fence get er done. Will locate switch so it would be unnecessary to access the battery compartment for quicker response for emergency shut down.

 

[ClimberRob]

I'm curious, was the IOTA converter turned on with power from shore power? When you say the main was turned off, are speaking of the DC main (push/pull toggle switch) or the AC main breaker?

Neither. I had just parked and was not connected to shore power. I had not turned the DC main switch on yet. However, the battery was still connected to everything before the distribution center, as it always is.

 

[ClimberRob]

The Iota converter was the first thing that jumped into my mind but in this case I believe we're reading about the Iota IDP-30 Distribution Panel used on many FWC campers (except shell models) up to 2012. The IDP-30 contains the AC and DC distribution panels and is also referred to as a power center or load center. Those campers also typically have an Iota DLS-30 AC-to-DC battery charger connected to one of the circuit breakers on the AC side of the IDP-30 so those have two Iotas.

I remember having a hard time finding a manual for the IDP-30 and then saw Happyjax's Well lookie what I found post with it in PDF form. It's interesting to see it has two black wires coming out the back for the 12-volt input connections and then separate red and blue wires, each marked with the fuse position, coming out of the back for the fuse panel's output connections. We can also see the IDP-30's DC ground connection in Figure F.

IDP-30 owners may also be interested in wuck's warts-and-all schematic of his 04 Hawk.

PS-- Glad to see you saved the camper and your truck, ClimberRob! I wish I had the electrical knowledge to be more helpful. Offhand, I don't understand why a fuse wouldn't have blown and I don't get what was drawing the power.
.

Yes, I am referring to the IDP-30 distribution panel. The main ground wire between the battery and that panel is the wire that had the issue. Thanks for the links.

As I stated in my first post, this "main" black negative wire running between the first "ground" terminal block (next to the water pump) and the back of the IDP-30 has many splices in it. It is not a continuous wire.

The issue must have been with a loose connection causing it to arc and increase resistance. This, in turn, caused the wire to turn into a mini heater-coil wire and overheat, burning off its insulation. I don't know what type of wire this was originally, as there is no insulation left on it, at all.

 

[ClimberRob]

I have entertained the idea of installing a marine type battery switch(main cut off)for a while now. After reading this I'll get off the fence get er done. Will locate switch so it would be unnecessary to access the battery compartment for quicker response for emergency shut down.

Good idea. I was very quick to disconnect the battery, but it still took over a minute.

 

[Vic Harder]

just a loose ground wire without any load connected to it can’t melt. something was drawing current through it. sometimes what happens is that another (main) ground connection is broken, and then the current all has to go through a wire not intended to be the main ground. that doesn’t seem to be the case with your situation. puzzling!

 

[klahanie]

Just had an electrical fire in my 2006 Grandby.



My plan is to replace the entire run with a doubled 12 AWG marine-grade wire and re-wire all of the individual splices with their own ground wire running to a new terminal I will install behind the IOTA fuse center.

It could have been worse...

Scary.

Years ago I relocated some fuses and installed a Iota DP30. I think FWC later started using the same model. IIRC the unit does have a neg bus bar with the provision for multiple wires. That might be an alternative to a new neg terminal block.

I like the idea of each circuit neg wire returning, unmolested, to the panel (or a common terminal) with a main neg wire then running to the batt bank.

I'd say 14ga is light, if for a 30 amp panel. As a coincidence, when doing mine, rather than run a new single replacement main neg wire from my DP, I connected a shorter wire to the oem neg feed wire from the batts - and had a burn out at that splice. Have to be mindful of connections with vibrations off highway.

Agree with a disconnect. IDK what FWC uses but I put in a marine battery selector type in the pos feed between the house batts and the DP. Like the peace of mind.

... and when you're checking the rest of the wiring, be a good time to check that fire extinguisher.

 

[PaulT]

I installed MRBF fuse holders on both positive & negative terminals. https://www.bluesea.com/products/5191/MRBF_Terminal_Fuse_Block_-_30_to_300A

I think Vic is onto a possible cause. Many ham radios come with fuses in both positive & negative lines for just the case Vic describes. If main return line fails, current will use whatever return path it can find. That may well be a wire that is too small for the task.

Paul

 

[XJINTX]

Just an FYI as we had smoke damage once at the house. Companies like Rainbow International Carpet cleaning and restoration have some kind of ionized type machine they can put in and it absorbs the smoke smell. Worked great in my garage insurance paid so not sure of cost

 

[ClimberRob]

just a loose ground wire without any load connected to it can’t melt. something was drawing current through it. sometimes what happens is that another (main) ground connection is broken, and then the current all has to go through a wire not intended to be the main ground. that doesn’t seem to be the case with your situation. puzzling!

The only load at that time, that I'm aware of, was my inline meter. It is not connected anywhere near the area with the issue occurred. The only ground wire running between the battery and the back of the fuse box was the single 14 AWG wire. Very puzzling, I agree.

 

[ClimberRob]

Scary.

Years ago I relocated some fuses and installed a Iota DP30. I think FWC later started using the same model. IIRC the unit does have a neg bus bar with the provision for multiple wires. That might be an alternative to a new neg terminal block.

I like the idea of each circuit neg wire returning, unmolested, to the panel (or a common terminal) with a main neg wire then running to the batt bank.

I'd say 14ga is light, if for a 30 amp panel. As a coincidence, when doing mine, rather than run a new single replacement main neg wire from my DP, I connected a shorter wire to the oem neg feed wire from the batts - and had a burn out at that splice. Have to be mindful of connections with vibrations off highway.

Agree with a disconnect. IDK what FWC uses but I put in a marine battery selector type in the pos feed between the house batts and the DP. Like the peace of mind.

... and when you're checking the rest of the wiring, be a good time to check that fire extinguisher.

Thanks. I realized that the DP30 had a negative bus bar on the back. It was already full, which I imagine is the reason FWC decided to splice in so many other lines off of the main negative run. I decided to add a Blue Sea bus bar in the back of the space where the old AC IOTA charging unit was and wire each negative wire individually.

My fire extinguisher is in good shape. It was the first thing out! Thankfully, I didn't need to use it.

 

[ClimberRob]

I installed MRBF fuse holders on both positive & negative terminals. https://www.bluesea.com/products/5191/MRBF_Terminal_Fuse_Block_-_30_to_300A

I think Vic is onto a possible cause. Many ham radios come with fuses in both positive & negative lines for just the case Vic describes. If main return line fails, current will use whatever return path it can find. That may well be a wire that is too small for the task.

Paul

Thanks Paul. I have been entertaining the idea of installing fuses at both battery terminals. I'm taking this opportunity to "upgrade" quite a few areas of the electrical system in my camper.

The main negative line was the ONLY line. It was, quite obviously, undersized for the task. The main positive line was 10 AWG, and the main negative line was 14 AWG. Probably a brain fart moment, or lack of materials on-hand, for the "worker bee" at FWC that day.

 

[ClimberRob]

Just an FYI as we had smoke damage once at the house. Companies like Rainbow International Carpet cleaning and restoration have some kind of ionized type machine they can put in and it absorbs the smoke smell. Worked great in my garage insurance paid so not sure of cost

Thanks. Thankfully, the smoke smell has almost completely cleared out already.