Old house, old 2 wire no ground 240 line question.

[Feijao]

I am trying to hookup a lighting controller but ran in to something that I know nothing about. When I went to disconnect the existing 240 line from the item that it was running I noticed that it only had hot wires. Here is a picture of the wire http://inspectapedia.com/electric/0588s.jpg its the one on the top right hand corner.

Is it safe to connect this wire to the controller without a ground? I doubt it is. Can I add a ground wire some other way?

Thanks guys,

 

[Can of Bliss]

That stuff is shitty. If it's possible, replace that wire all the way back into the breaker box.

If you can find a nearby wire that is grounded, you could connect that to your ground. This is not recommended, but I think would be safer than running without any ground.

 

[Feijao]

I am not able to rewire back to the breaker box at this location unfortunately.

Thanks,

 

[sheik_yerbouti]

You can install a gfci plug or gfci breaker to make it safe.

I'm not sure how your lighting controller gets power though so if it has a plug then just install a GFCI outlet where you plug it into, if it is direct wired than putting a GFCI breaker on the circuit it is on should make it safe. I'm not positive about that last bit but I know in the code book you can use that 2 wire without ground in a house to replace an old outlet if you use a GFCI outlet so I'm thinking that it's the same concept if you protect the circuit with the GFCI breaker. They are about $100 though (in Canada)

 

[BlackMarketMic]

He said he doesn't have access to the panel, apt probably. Also running a ground to a gfci that is hooked to an ungrounded wire won't magically make you grounded. Anyways old wiring and old receptacles did not use a ground back then... I have worked in several old houses who were completely wired with #14/2 awg without ground and they have never had electrical problems nor fires.. First of all check your contoller to see if you really need to ground it for it to function. If you don't need it then don't sweat it, obviously a grounded device is safer but unless one of the live wires on your 240v line accidentally loosens and touches the side of your controller it would become energized and if you were to touch this ungrounded energized device you would act as the ground and get a shock and probably not even trip the breaker this is the reason almost everything is grounded now. Also an electronic device might get damaged from being accidentally energized..Like suggested above running another wire from a nearby outlet or light switch (if you live in usa your switches are grounded if your in canada forget it we don't bother grounding our switches because our code does not require it.) If all outlets available are without ground then you will have to make your own. Phone and satellite guys often run a bare copper wire to the water entrance pipe if it's metallic. You can buy a clamp that goes on 1/2" -3/4"-1" pipes that will connect to a bare copper ground wire just make sure you get a proper sized bare for whatever amount of current your controller is drawing. Also install the bare clamp before the municipal water valve in case a plumber does some work and cuts off the pipe to modify installations, they usually shut off the main valve and cut pipe after the main valve if your clamp is before the main valve he won't be messing with your ground. This is not ideal but it would be grounded... This is if you have access to water mains. I personally wouldn't even bother with grounding it but I have become a bit de sensitized to the dangers of electricity I work as commercial electrician with 600/347 v on regular basis. You could run a wire from your device to the outside and install your own grounding rod or plate, you will be grounded but definitely not code, electrical installations can only be grounded to a single grounding rod.. Electricity is a complicated biatch, between function and being up to code are two different things..

 

[AvidLerner]

find a ground. or create as ground. usually heating equipment is rounded from the furnace. IF you can put a ground rod and create a ground for your controller. A two wire system has an opportunity to blow circuits. GFCI cannot work without a ground circuit. Only faking it with a two wire. Find a grond. make a ground and run a double 00 for a ground loop

 

[GOT_BUD?]

Any chance the existing wire is running through conduit? 'Cause that'd be grounded.

 

[MJPassion]

If you must have a ground & plumbing is updated to pvc, you can purchase a 6ft long grounding rod for electric fences & pound it into the ground & attach a grounding wire to it.

GFCI must be grounded to work so that's not an option.

 

[Floridian]

A gfci does not need a ground to operate properly as it detects any slight difference in current between hot and neutral and trips accordingly.You must mark the receptacle with a no equipment ground sticker though.Since we are talking about a 240 volt circuit a gfci isn't an option.AvidLerner said it best if you want a ground you must find one or create one.

 

[Jhhnn]

I am trying to hookup a lighting controller but ran in to something that I know nothing about. When I went to disconnect the existing 240 line from the item that it was running I noticed that it only had hot wires. Here is a picture of the wire http://inspectapedia.com/electric/0588s.jpg its the one on the top right hand corner.

Is it safe to connect this wire to the controller without a ground? I doubt it is. Can I add a ground wire some other way?

Thanks guys,

You have access to the breaker panel, I assume, in order to be able to work on it at all, right?

If so, you can install a 240v GFCI there because they need to have a neutral to work afaik. You won't have a ground at the controller but you don't need it with GFCI protection.

Your panel may be too old to get a GFCI to fit. If so, you can create a safety ground at the controller either via a cold water pipe or a ground rod. Test it with a meter. Be sure to use wire at least as large as the supply wires. It's a kluge, but it will work. Do not use that ground as a neutral to run 120v equipment. It's just a safety. Be sure that your controller doesn't need a neutral to operate.

 

[dufous]

Apparently, not.

He said he doesn't have access to the panel, apt probably.

I am not able to rewire back to the breaker box at this location unfortunately.

You have access to the breaker panel, I assume, in order to be able to work on it at all, right?

 

[Jhhnn]

Apparently, not.

Well, he said he was disconnecting existing equipment so I hope he isn't doing that with live circuits.

 

[Feijao]

Thanks guys for all the help. I was able to create a ground via a water inlet that was near by.