I have a set of plans that require an equipment grounding conductor to be connected to all metal boxes. How many of you guys pigtail to each metal box in a system? is it not true that the metal to metal conduit connection should be enough ?

I ground every box. Yes the pipe would cover you code wise but the conductor is a back up.

I almost always install an equipment ground wire in metal raceways. By the way your worded your question I'm not sure if you asking about installing the wire or connecting the wire to the boxes if it is installed. 250.148 requires the equipment ground wire to be connected to any metal boxes that the circuit conductors are spliced in.

You need a pigtail when the receptacle is not self-grounding. I have yet to see a GFI that is. A self-grounding receptacle has a clip or spring that tightens the connection between the yoke and the screw.

I check for it during inspection. I ask for all the boxes to be bonded.

OOPS……..Last night when I posted I was just clicking on the updated topics but didn’t read the title. This morning I see that the title of this post is about 250.148. Back to first grade reading class for me.

Curt


[This message has been edited by caselec (edited 04-16-2004).]

Almost fell for this (lazy bone) - had a metal j-box inbetween 2 runs of NM. It was out of the way, almost just tied the 2 grounding wires together withou attaching to the box.

But then I thought...[size4]WWJTD?[/size]
What Would Joe Tedesco Do?

I pigtailed.

[This message has been edited by DougW (edited 04-16-2004).]

i will ground every metal box both pigtailed and run the grounding conductor as back up in case the conduct get loosen up [ which i see it happend from time to time].

before i get way off the point here let you know the 4X4X21/8 box i use is Raco #244 .,,, if some of you are famiur with it i will say that work the best for surface mounted area escpally the cement wall types [ it have raised ground screw in one corner of box ] .,,,

sorry for change the subject for a min


merci, marc

code is code but you stated that the prints calledfor a separate ground wire. anytime i see the print or a spec for a job which calls for the installation to go beyond what the code requires thats what i install.

Frenchelectrician's post got me thinking...

Is it just me, or are almost all of the 1900's/4"x4" J boxes now are the "cement wall" type, with the raised area for a grounding screw?

I haven't seen a flat backed one in a while now.

Thank you guys for the input, I have always wondered about whether to attach an egc to each metal box,or not.

DougW: I order exclusively Cooper Crouse-Hinds j-boxes and always purchase the raised threaded ground screw mount.

MJ: I, too, use an EGC in each metal box.

If the circuit conductors run through a metal box without splice, then the box does not have to have the e-ground wire attached to it, does it?
I would attach it anyway.

I usually don't pigtail to the box. Normally I'll strip a section of the incoming (upstream) power's EGC, (makes it easier to identify which is the "hot" side later) wrap it around the ground screw or through the lug (lay-in lugs are great for this), and splice the other grounds to the end of that conductor.

Wow! you guys are all together on this one. I'v been in the trade since '79 and I don't think I've ever grounded a box in a pipe run unless it was specked. If I'm wrong point me in the right direction.

If you have a metal P-Ring or a raised cover, Doesn't that automaticly bond the box?

Does the NEC say you have to have a pigtail to the box eventhough the P-Ring and the Raised cover plate is metal and the receptacle has a good mechanical connection to the ring then to the box?

Not that pigtailing is a big job, just want to know for my own info.BTW i am with Curt i always pull grounding through all my piping.

Edward

[This message has been edited by Edward (edited 04-20-2004).]

2002 NEC 250.148

Always follow the specifications and plans.

I recommend the installation of the additional EGC. It is another way of being sure that the path will be there when needed, especially when the fitting vibrates loose.

That was an issue discussed at the proposal and comment meetings for the new code.

Ryan, please tell them about the EGC raceway fill requirements in Chapter 9, and the adjustment factor in Article 310.

How close are you to St. George, UTAH?

Hi Joe! I'm about 300 miles North of St. George. St. George is just over the border from Arizona. If your headed that way, I'm sure you'll enjoy the climate this time of year, and if you have time, take a minute to enjoy some of the scenary outside of town. Drop me an e-mail when your around and I'll see if I can't make it down there.

As far as raceway fill goes, the EGC must be counted because it consumes some of the volume of the conduit. When I think about raceway fill, I am thinking that we are trying to protect the conductors from damage while in the process of installing them. With that in mind, the EGC counts. Note 1 to the table tells us that the raceway fill section is dependant upon a moderate number of bends and length of pull. That is why you can load a nipple with more wire...your not pulling the conductors, but instead you are pushing them...much less probablity for damge.

As far as the ampacity adjustments go, the EGC need not be counted as a current carrying condutor because, under non-fault conditions, it does not carry current. The only issue that I have is that, in my opinion, if you have to increase the size of phase conductors and grounded conductors becasue of ampacity adjustment, you must also increase the size of the EGC, as per 250.122(B).

Thanks Ryan:

Good explanation. I asked about UTAH because my wife is stranded there now because her Uncle who is 96 years old is in intensive care.

I've got 2 switchs in a double gang raised cover going on a surface mounted 4 sq. The switches don't have the grounding spring. I pigtail the box and one of the switches, do I have to pigtail the other switch. BTW I did but just curious