Originally Posted By: jfarsetta This post was automatically imported from our archived forum.
Todd,
Why wouldnt the metallic conduit be a suitable ground? It typically is ised in commercial applications all the time. The conduit serves as a safety ground. It mechanically and electrically bonds cabinet to cabinet.
-- Joe Farsetta
Illigitimi Non Carborundum
"Dont let the bastards grind you down..."
Originally Posted By: tallen This post was automatically imported from our archived forum.
As far as I know A ground wire must be installed. It was at one time ok 1993 I think to leave the ground wire out and rely on the conduit. I think that has changed. All devices must be electrically bonded. I would hunt down the code reference ,but I don’t want to
Help Joe!!
-- I have put the past behind me,
where , however, it now sits, making rude remarks.
Originally Posted By: jpope This post was automatically imported from our archived forum.
The conduit would certainly be adequate for bonding. Most (not all) equipment panels I see, have no grounded conductor feeding them, only two “hot” and a neutral.
Originally Posted By: tallen This post was automatically imported from our archived forum.
Ok you got me I just looked it up. A sub panel may be bonded by metal conduit.
I still think a loose ground wire should be secured by a lug.or removed. Code says 4 conductors two ungrounded a neutral and an equipment ground which may be metal conduit. If the wire is there it still needs to be secured.
I do apologize. I will make a point of looking things up before responding from now on.
I would still call for a sparky with a loose wire hanging around.
Damn I feel bad.
Bad electrician
Cheers and Happy 4th
-- I have put the past behind me,
where , however, it now sits, making rude remarks.
Originally Posted By: rmoore This post was automatically imported from our archived forum.
Looking at the first photo, it doesn’t look like there would be any chance of the loose grounding conductor coming in contact with anything hot…so I’d also say there’s no problem here…other than the two half-size unprotected slots in the dead-front cover (?).
But...the bare aluminum conductor would be a superior EGC and it does seem silly to have it there and not connect it. Tough to call in a Sparky for something that's not really wrong. What did you do Jeff?
-- Richard Moore
Rest Assured Inspection Services
Seattle, WA
www.rainspect.com
Originally Posted By: jpope This post was automatically imported from our archived forum.
Joe,
There is actually only one. It came up from the bottom and looped back down, and yes, it was part of the feed from the service panel.
My recommendation was for further evaluation. This was an easy recommendation as there were several mis-wired outlets and faulty GFCI's that needed replacement as well.
Also, I have no way of knowing (although I could assume) that the metal conduit is continuous all the way to the service panel. As I said, they were 100 feet apart.
They exit the service panel in 2" conduit with other circuits and entered this panel through a 3/4" conduit.
-- Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738
Originally Posted By: cbuell This post was automatically imported from our archived forum.
It would be nice to get some real clarification on the issues in this thread. It has been my understanding that there had to be four wires to the subpanel and that the neutrals and grounds had to be isolated. At 100 ft I have heard that 3 wire can be run if ground rods are driven for the equipement grounds at the subpanel but even then the grounds and neutrals would be isolated. Any comment?
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
First if the conduit is electrically continuous it can be used as the EGC (equipment grounding conductor).
This info can be found in the NEC section 250.118 Types of Equipment Grounding Conductors.
As for the separation of neutrals and grounds.
Any panel or electrical equipment that does not contain the service disconnect but is located in, or on the same building or structure as the service disconnect must have the neutral and grounding conductors separate.
The only exception to that that an HI would need to consider is existing ranges and dryers.
Now if we have a panel in a separate building or structure (like a detached garage) it is the installers choice to separate or not separate the neutral and grounding conductors.
Grounding electrodes (rods water pipes etc.) are required for any and all panels located in or on a separate building or structure.
Originally Posted By: kmcmahon This post was automatically imported from our archived forum.
So in this panel located directly below the main with the disconnect located in the main panel, it is supposed to have seperate busbars for ground and Neutrals right?
Originally Posted By: Ryan Jackson This post was automatically imported from our archived forum.
lfranklin wrote:
I'm confused 
So if a sub in a different building with it own grounding rod, the neutral and grounding conductors can be together. Is that what I'm reading?
Sometimes.
1) The feeder circuit to the panel must not contain an equipment ground and
2) There can be no metallic paths between the two buildings, such as gas, water, phone, coax, etc...
If there are metallic paths between the two buildings, ultimitley they will have to bonded at each structure. In doing such, you would have nuetral current taking two paths. Path #1: The grounded (nuetral) conductor. Path #2: Through the main bonding jumper, to the grouind rod, through the earth and onto the metallic path, back to the first building on its way back to the transformer.
Originally Posted By: lfranklin This post was automatically imported from our archived forum.
Thanks Ryan
One more question If they add a telephone or coax for TV then the neutral and grounding conductors need to be separated. But if there is no metallic connection between the building then they can be together?
I don't know if I'm even asking the question right.
Originally Posted By: Bob Badger This post was automatically imported from our archived forum.
Larry you are asking a great question.
The electrician installing the feeder is only required to consider what is happening at the time of installation they do not have to predict the future.
However the fact that a metallic path may be created later is the primary reason not to use the grounded conductor as the grounding conductor.
IMO, there are very few times using the grounded conductor as the grounding conductor is a wise idea even when allowed.
Originally Posted By: Ryan Jackson This post was automatically imported from our archived forum.
Larry: The TV will utltimatley be earthed at both loacations, and therefore nuetral current will travel back on the coax’s sheild. A 4 wire feeder would be required.
I agree with Bob...the code may allow it under certain conditions, but I think the electrician really should consider future mishaps and pull 4 wires, but again, sometimes he/she doesn't have to.
Originally Posted By: jtedesco This post was automatically imported from our archived forum.
This question requires a Code Style Answer so that it will not be misinterpreted. This is a responsibility of the electrician and the following rule is mandatory!
Ask the electrician if this section is understood?
Quote:
250.94 Bonding for Other Systems.
An accessible means external to enclosures for connecting intersystem bonding and grounding conductors shall be provided at the service equipment and at the disconnecting means for any additional buildings or structures by at least one of the following means:
(1) Exposed nonflexible metallic raceways
(2) Exposed grounding electrode conductor
(3) Approved means for the external connection of a copper or other corrosion-resistant bonding or grounding conductor to the grounded raceway or equipment
FPN No. 1: A 6 AWG copper conductor with one end bonded to the grounded nonflexible metallic raceway or equipment and with 150 mm (6 in.) or more of the other end made accessible on the outside wall is an example of the approved means covered in 250.94(3).
FPN No. 2: See 800.40, 810.21, and 820.40 for bonding and grounding requirements for communications circuits, radio and television equipment, and CATV circuits.
