E.M.T. good for ground

Status
Not open for further replies.

captaincrab55

Senior Member
Location
Maryland
480sparky said:
41116extensin.gif
Why do they still put KO's in extension boxes?...:-? :grin:
 

mdshunk

Senior Member
Location
Right here.
There was a report out in 1994 from Georgia Tech that had a chart for the usefulness of conduit as a ground. Most of the limits were around 300 feet in that model, from tables 6.1 and 6.2. The Steel Tube Institute has a free program caled GEMI that will figure this out for you, based on Georgia Tech data.

For your free copy of the GEMI CD,
contact the Steel Tube Institute,
2000 Ponce de Leon, Suite 600
Coral Gables, Florida 33134
tel: (305) 421-6326
e-mail: STINA@steeltubeinstitute.org
 

chris kennedy

Senior Member
Location
Miami Fla.
Occupation
60 yr old tool twisting electrician
iwire said:
And that is different from a PVC or NM job how? :grin:

Because the PVC conduit or NM won't sit there energized in the event of a fault waiting for Bob to become a ground fault path.
 

iwire

Moderator
Staff member
Location
Massachusetts
chris kennedy said:
Because the PVC conduit or NM won't sit there energized in the event of a fault waiting for Bob to become a ground fault path.

No, just every bonded item downstream including plugged in appliances.

Getting a beer out of the fridge could be a surprise. :D
 

chris kennedy

Senior Member
Location
Miami Fla.
Occupation
60 yr old tool twisting electrician
iwire said:
Getting a beer out of the fridge could be a surprise. :D

My fridge is wired as per 517.13. And I'll be logging off now as that sounds like a great idea.

GO GIANTS!!!
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
chris kennedy said:
Because the PVC conduit or NM won't sit there energized in the event of a fault waiting for Bob to become a ground fault path.

This is the very reason our respected late friend Bennie Palmer would say it's safer not to ground or bond anything in a raised wooden structure.


Roger
 

iwire

Moderator
Staff member
Location
Massachusetts
roger said:
This is the very reason our respected late friend Bennie Palmer would say it's safer not to ground or bond anything in a raised wooden structure.

I agree.

I wish I remember the exact words he used but the message has stayed with me.

He said, more or less

By bringing the EGC into the room we have brought half the circuit needed to kill someone.
 

mdshunk

Senior Member
Location
Right here.
iwire said:
By bringing the EGC into the room we have brought half the circuit needed to kill someone.
Which is one reason I feel that GFCI protecting an old 2-wire circuit if you want 3-wire receptacles is safer than rewiring that circuit. The GFCI will trip at 5 or 6 ma. The grounded circuit will permit a fault to exist up to the ratign of the OCPD.
 

jerm

Senior Member
Location
Tulsa, Ok
Jim W in Tampa said:
How about we weld all the emt ?LOL

have you ever tried this?! It's nearly impossible, I tried tig, mig, and stick. they all blow holes in it even at low settings, until you're so low it won't stick. I'm sure a real welder could figure something out, but I couldn't weld it at all!!!
 

Jim W in Tampa

Senior Member
Location
Tampa Florida
jerm said:
have you ever tried this?! It's nearly impossible, I tried tig, mig, and stick. they all blow holes in it even at low settings, until you're so low it won't stick. I'm sure a real welder could figure something out, but I couldn't weld it at all!!!

I was joking it would not be legal
 

mdshunk

Senior Member
Location
Right here.
Jim W in Tampa said:
I was joking it would not be legal
If it was, it could be done. Commercial ductwork guys can MIG 30 gauge sheet metal. I took a night school welding class where the instructor TIG'd back together a Mountain Dew can.
 

iwire

Moderator
Staff member
Location
Massachusetts
jerm said:
what "law" would welding emt break?! some sort of welding statue I don't know about I guess.

300.18(B) prevents the welding of raceways.

Kind of a bummer as I have 'seen' ;) some really nice wire ways that where welded in place. Good grounding continuity and no nuts and bolts to poke the conductors.
 
Status
Not open for further replies.
Top