Splitting 240V

Dec 29, 2013 27 Replies

I've got a junction box with some 1953 sheathed cable feeding it. Looks like asbestos fiber sheath with silver spray paint on the exterior. Only 2 wires, both black. Measures 240V rms.



Leaving the junction box are some armored cables containing 2 wires each, one black, one white. They also put out 240V rms. There are no neutral wires or ground wires that I can see. The armored cable is well grounded however.



I had expected that the black/white pairs were 120V, but they are not.



How bad an idea would it be to choose either the black or white wire and connect it to the hot side of a 120V outlet, and then connect the neutral side of the outlet to the armored cable?



And yes, I will call an electrician if I start to feel dangerous.



Shouldn't be asbestos, most likely cloth wrap wire. Very common back then and put inside of BX (armor).

THat does not sound correct, are you in the US? or some 240 land country?

Measure from the ground to each lead, see if you're getting 120v then..

It's possible that one particular line was wired for something like a hot water heater or something that needed 230 volts.

Look on the box and see if the black and white are both going to the L1 and L2 legs, not ground/neutral. If so, it was wired for a 230 volt application. Simply move the white wire over to the ground bus at the panel..

Jamie

This is USA.

Measures 110v from each to ground

This was a circuit that in hindsight was definitely 230/240v.

Was hoping to not do any work at the panel, because I'm not sure what else is on that line. Wanted to just split the 240 at the terminal end.

A small transformer might be an alternative to replacing a lot of wiring etc.

A small transformer will not be TO CODE.

Get an electrician and do it properly :')

"Stumpy" wrote in news:Er2dnWrlee_X8SLPnZ2dnUVZ snipped-for-privacy@earthlink.com:

*Very* bad. The cable armor will then become electrically live whenever the circuit is in use.

That's not the right standard. You need to call an electrician if you start to *act* dangerous.

And you're at that point now. What you propose doing is potentially deadly.

ike asbestos fiber sheath with silver spray paint on the exterior. Only 2 w ires, both black. Measures 240V rms. Leaving the junction box are some armo red cables containing 2 wires each, one black, one white. They also put out 240V rms. There are no neutral wires or ground wires that I can see. The a rmored cable is well grounded however. I had expected that the black/white pairs were 120V, but they are not. How bad an idea would it be to choose ei ther the black or white wire and connect it to the hot side of a 120V outle t, and then connect the neutral side of the outlet to the armored cable? An d yes, I will call an electrician if I start to feel dangerous.

Any chance of running a neutral wire from the panel to where you want to sp lit the 240V circuit into two 120V circuits. Are we talking 10 feet or 30 feet or a mile, or what???

If you are not using the 240v, re identify one of the wires white (tape works) at both ends and connect that one to the neutral bus in the panel. You then made a 120v circuit from the 240v circuit.

ike asbestos fiber sheath with silver spray paint on the exterior. Only 2 w ires, both black. Measures 240V rms. Leaving the junction box are some armo red cables containing 2 wires each, one black, one white. They also put out 240V rms. There are no neutral wires or ground wires that I can see. The a rmored cable is well grounded however. I had expected that the black/white pairs were 120V, but they are not. How bad an idea would it be to choose ei ther the black or white wire and connect it to the hot side of a 120V outle t, and then connect the neutral side of the outlet to the armored cable? An d yes, I will call an electrician if I start to feel dangerous.

All right. I'm getting the impression that the right way to do this is to change it at the panel. It's a 1953 panel and I'm reluctant to even open it up right now. The extension cord solution is OK for now, hardwire later.

DO NOT use safety ground as neutral!!!!!!

100% against code - for good reason

Any chance of running a neutral wire from the panel to where you want to split the 240V circuit into two 120V circuits. Are we talking 10 feet or 30 feet or a mile, or what???

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No. The panel is now in the interior of the house. It has had additions added so that what was the exterior is now in the center of the structure. walls are very thick - maybe lathe and plaster construction. It would be very hard to add a neutral wire from the panel. I could easily add a neutral wire from some other junction box - hope an inspector never sees it.

I think I'll drop this project and just get by on a male plug plugged into an outlet that then goes through a conduit to a duplex outlet. I'll get a pro to do it right if I ever sell the house.

It is against code to run a separate neutral even if it WAS possible.

snipped-for-privacy@snyder.on.ca submitted this idea :

And its most likely against code to run a cable from an OUTLET thru a conduit to a duplex outlet. DONT DO IT :-@ .

That is the equivalent of running an extension cord through an obstacle. I can unplug it at any time and would not be considered a permanent improvement.

Not rocket science...call the building inspector. His opinion is the only one that counts.

Read the exceptions for class 1 transformers < 1000va

I think you mean "endangered".

Having read your post, I think you are already dangerous.

That gets my vote too.

It's a 1953 panel and I'm reluctant to even open it

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