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[Mike Sokol]

This is a picture of a bus conversion wiring mess from one of the RV camping forums I'm active on. If you think that live sound gigs are the only places with dangerous wiring, think again. This RV stuff is just plain scary. 

[Keith Broughton]

Once again....I'm speechless!!!!
I cannot, for the life of me, figure out how even the most dull of thinkers can consider this to be OK

[Tim McCulloch]

Mike, this was *inside* the RV unit, or at a campsite?  Either way I'd run.  Fast.

[Mike Sokol]

Mike, this was *inside* the RV unit, or at a campsite?  Either way I'd run.  Fast.

This was inside the back electrical compartment of a passenger bus/coach that had been "retrofitted" as an RV-Camper. These bus guys are notoriously cheap, buying worn-out passenger coaches and school busses, then turning them into family campers in their backyards. Some of the retrofits as pretty nice, while other are a complete Cluster F***.

They were recently in a big argument about needing to keep the entire chassis of the bus isolated from the incoming EGC safety ground on the shore power line because they think you can't mix the 12-volt DC and 120-volt AC "grounds".  Of course, you need the bus chassis bonded to the incoming shore power EGC/safety-ground to comply with code, but apparently a lot of them are not bonded on purpose.

Here's another wiring pic from the same thread.

[Mark Cadwallader]

Do they figure that they need SAE spec stranded wire for the 12 vdc and "Romex" for the 120 vac in order to "do it right"?  Mark C.

[Mike Sokol]

Do they figure that they need SAE spec stranded wire for the 12 vdc and "Romex" for the 120 vac in order to "do it right"?  Mark C.

One thing that's easy to goof up in RVs and Tour Buses is that the "ground" wire of 12-volt DC gear is typically Black, while of course the Hot wire of the 120-volt AC system is also Black. These guys are worried about the 120-volt AC "ground" intermingling with the 12-volt DC "ground" and blowing up something. Perhaps they're just hooking all the black wires together and turning on the power. That would make something bad happen.   

[Stephen Swaffer]

Perhaps they're just hooking all the black wires together and turning on the power. That would make something bad happen.

But that kind of bad is not nearly so bad as what might happen to a person touching an unbonded chassis.

The sad thing is so often you see stuff like this and it could have been done easier and safer the right way.

Romex  is only allowed in wood frame construction .  Steel frame needs to be either conduit or MC.  But maybe the RV industry is an exception.?

[Mike Sokol]

But that kind of bad is not nearly so bad as what might happen to a person touching an unbonded chassis.

Yup, there have been a number of electrocution deaths over the last few years from these bus conversions while they were sitting in the back yards being converted. They power them up from shore power while they're working on them. I remember one death 3 years ago when a toddler was electrocuted while standing on the ground and touching the obviously unbonded door frame of the bus his parents were working on. That's a separate incident from the electrocution last July of the 3-year old boy who was stepping out of his family's Airstream trailer which was powered from a shed outlet that lost its ground.

I do what I can, but very few of these guys take electricity seriously enough. 

[Frank DeWitt]

Yup, there have been a number of electrocution deaths over the last few years from these bus conversions while they were sitting in the back yards being converted. They power them up from shore power while they're working on them. I remember one death 3 years ago when a toddler was electrocuted while standing on the ground and touching the obviously unbonded door frame of the bus his parents were working on. That's a separate incident from the electrocution last July of the 3-year old boy who was stepping out of his family's Airstream trailer which was powered from a shed outlet that lost its ground.

I do what I can, but very few of these guys take electricity seriously enough.

Perhaps some simple recommendations would reach a couple.  (As apposed to teaching them how to be an electrician or teaching them not to do it.

Step 1  Connect the skin to the frame with a big wire.
Step 2  Connect the frame to the shore power ground.

Now proceed with the conversion.

Question.  If many trailer owners (RV boat, utility, ETC) have trouble keeping the stop / tail lights working then why would anyone expect the AC to be safe and work correctly.

[ProSoundWeb Community]