[amakarevic]

I need to connect a new traveling cable that has ground with some old (possibly >50 yrs old) armored cable that has only black and white wires, i.e. no ground. I wonder if it will be OK that I just piggytail the new cable's ground and wrap it at the grounding screw in the connecting receptacle.

thanks

 

[frenchelectrican]

I need to connect a new traveling cable that has ground with some old (possibly >50 yrs old) armored cable that has only black and white wires, i.e. no ground. I wonder if it will be OK that I just piggytail the new cable's ground and wrap it at the grounding screw in the connecting receptacle.

thanks

It depending on if you have plastique or metal box the latter one is best but if you have plastic box then we will go extra step to get proper grounding set up for old BX cable they are pretty tricky if not addressed properly.

IMO it will be wiser to just run new MC or NM cable to replace the old BX cable if possible.

Merci,.
Marc

 

[amakarevic]

merci but i have to use armored cable because the circuit spans 3 floors (code reg in my jurisdiction). attached is the photo i am using. and i always go with metal boxes/receptacles.

 

[nap]

that is not armored cable (AC). That is metal clad (MC) cable. What do your codes specify?

 

[amakarevic]

that is not armored cable (AC). That is metal clad (MC) cable. What do your codes specify?

i thought it was the same thing

 

[nap]

i thought it was the same thing

similar but not the same. AC cable can use the sheath as an EGC due to the bonding wire that runs inside the metal sheath. Due to that, it does not have to have a separate egc within. MC sheath is not an acceptable egc but it can be purchased with an egc (such as I see yours has).

There is a difference in the material used to wrap the conductors as well. If I remember correctly, MC uses a paper wrap and AC uses a plastic wrap. Not sure of that and it may have changed since the last I worked with it.


so, does your code spec AC specifically?

regardless of which you use, be sure you use the proper connectors. There are some that can be used with either but there are also some that are listed for use with just one or the other.

also, one requires the use of the red insulators in the end of the sheath and the other doesn't (although most people I know use them in either). It's late and offhand I cannot recall which requires the insulators and which one doesn't.

 

[amakarevic]

metal clad. thanks.

 

[frenchelectrican]

The metal clad { MC } is easier to deal with grounding than BX but I am sure your area will allow MC without much issue but if you have to use the old BX cable for some reason make sure you use proper connectors there is two verison on market so just watch out on them.

For the antishorting bushing it is mantory on BX but MC it is toss up but I Like to use them anyway.

Did you get the rotary cutter for the MC cable I will post the photo here real quick.,

This tool will be a big time saver espcally if you do more than just few cuts on them and I Have couple with me.

And make sure you bond the metal box with ground jumper something like this.

Hope that help you with it.

Merci,
Marc