Guys I've done very little commercial or open wall work. My question is I'm wiring a work shop (40 x 40), open beams and purlins. Sould I use BX as my trunk line then enter a junction box then use EMT to drop down to the recepticals and light switches.
Also since I will be useing single stranded wire (black, white, & green) should I run my ground (green) conductor all the way back to the service panel or is it acceptable to bond the ground in the metal boxes useing the EMT as a path for the ground as long as I use a bonding ring that the panel.
I run bx to emt all the time is the bx going to be hidden in a ceiling?I would run a ground in the emt because both compression and screw type connectors are crap.Then again i usually skin the bx to length and use a BX to EMT connector to transition to the pipe without a box and you have bare ground right there at the devise.
Bert, You should be fine doing the job as you stated, as long as it's all installed properly, and there aren't any local ordinances prohibiting it. Either Type MC or AC cable will work well. EMT is approved for grounding by the NEC, and bonding jumpers should be installed to the devices from the boxes that they are in.
Frank, I'm curious Why do you think all EMT connectors are crap? What is a BX to EMT Connector?
Was there a problem with these 1/2 pipe to 3/8 flex connectors having the UL listing removed? If so why? I know a number of inspectors that won't accept these. I could not find them in a Regal catolog.
OK guy's maybe were talking about different cable.I thought he was referring to AC90.When we order bx 12/2 from the wholesalers around here we actually get AC90.I have to specify BX skin and diameter if I just want the aluminum cladding.The only time we use bx skin is for fire alarm or communication circuits and it never has the bonding strap in fact i thought they didn't make it like that anymore.Same goes for the connector.EMT is almost always run with a ground around here because a lot of the time the connectors come loose and compromise the ground from vibration improper installation or rough usage.While inspection will pass some EMT installations without a ground wire they generally let you know they don't like it.I would run AC90 to EMT with a connector or go all pipe before i bothered with pulling wire in bx skin.Sorry for the slang terminology but bx and AC90 is the same here my mistake. RobbieD, Thats the connector i was talking about.
Iwire,I have never seen the bonding strip come in AC90 just the bare ground wire.
[This message has been edited by frank (edited 12-02-2004).]