I was asked this today due to a wrong spec on a job. The shade company required a 12-2 romex at each window shade location for power, so I did it. I went there today to start the install and reading the shade info it needs a 12-3 romex to work. The shade guy wants to use the ground conductor as a neutral and I told him no way no how. I am just thinking now though what is the real reason behind this. Safty because no ground? The current on the neutral now is not insulated on it's return trip?
OK, the bare conductor will be carrying the current as you said, and basically be "live" to a grounded object, box, etc; or a person.
YES it is a saftey issue, yes, it is NOT NEC compliant, and yes you are 100% right saying 'no way'.
I have seen instances where EMT was used as the 'neutral' for a 30 amp, 120 volt circuit that consisted of ONE 'hot' conductor. Yes, it worked, but the setscrew couplings were not tightened properly and started arcing. It almost caused a fire, as the EMT was installed on a wall that had clothing racks mounted on it.
Some of the 'old timers' used to say "gyp the ground" when you had a 'open' neutral to restore the circuit; heck I saw BX armour that was 'live' arcing on suspended ceiling grid.
You're right; illegal, unsafe, and not to be done.
#54482 - 07/29/0508:09 PMRe: why not use the ground in a romex as a neutral?
I know not to do it and will get paid to fix it. The shade system is part of a larger system that is all tied together for controlling lighting, video and sound systems so doing anything but snaking in new cables will not work.
#54485 - 07/30/0505:55 AMRe: why not use the ground in a romex as a neutral?