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	Subject - Equip. grounding conductors to panels. Steven T. Okay, here's everbodies chance to beat up a near layman or maybe help the poor sap out. Here's my dilema. I'm dealing with a single phase service provided a supply by way of a direct burial (i.e.; a three conductor, ARMOR SHIELDED) cable which connects between two distribution* panels (i.e.; one serving as a structure's service disconnect means and the other the structure's dist. panel), then shouldn't the service disconnect's branch circuit's AC shielding required to be landed on the ground bus or other direct means of bonding to the equipment grounding conductors, and if so, isn't the shield at the structure's dist. panel also req'd to be bonded to the building ground? What I have on my hands are shielding that's simply jammed inside the metal sleeves that enter these panels (no conduit, just sleeves). Sure I know, it's supposed to have protection and not be exposed to damage, but I'm overseas in Kuwait this's commonly done and no one cares. But as to at least assuring substancial and code required grounding, I'm trying to get at least the grounding done right. So, do either or both of these EG connections (with AC shields simply 'bonded' to the panels and the panels bonded to the ground cable (leading to the ground rod) constitute code supported EGC bonding and a legitimate EGC circuit? I'm leaning towards 250.130(A) requiring the shields to be landed to the EGC terminal (either thru the ground bus or bonding jumper to the ground rod itself) and not using the panels themselves as a EGC. zapped208 Do whatever you think is right, your in Kuwait. Steven T. A bit aside the point and should go w-o saying. If anybody has legitimate take on my interpretation being right or wrong, please either slap me stupid, or pat me on the back. zapped208 OK StevenT,- Yes you should bond everything and use the proper connectors/fittings. You should have a g rod at the service,and bond the building at this point. At the sub panel also install proper fittings and do not bond the neutral buss to the panelboard. Install another g rod and use this for your equip. grounds. It would also be nice if you could get a forth wire to the sub panel, for your feeder equip. ground. You also not say how far away the sub panel is from the service disconnect. BTW Happy New Year! Steven T. The 120V panel is something like 80 yds away and you have to climb up on a wall to see the structure it supplies. The 240V panel (supplying a 200A feeder to the structure) is in plain sight and about 100 feet away. The distance and sight issues, are valid ones, but I'll be lucky to get them to even support the 240V panel's 400A feeder (i.e.; unsleeved, exposed on the ground and w/o protection where it enters the panel's bottom knock-out). They did "tape on" some excess stripped off jacketing there though. My issues here are only that at least the grounding is to code. So am I wrong in believing the code disallows the panel body to be the EGC and that the shield (EGC) be landed directly onto a post tied to the grounding rod? In other words, either the feeder's shield must landed at a ground connector (or post on the panel) leading to the ground rod, but not merely jammed into a sleeve at the bottom of the panel, right ? zapped208 Stevent,- An EGC is not a panel or armor, it is a conductor that is taken from a panel main disconnect and attached to a driven rod or underground copper water line. You cannot merely jam the cable in, you must use a connector. The neutral and equip. grounds and panel main disconnect should be all bonded together at this point only, and also the EGC. Steven T. zapped208,- Yes, as each end of this supply conductor has a ground rod, and in that each panel has this armor shielding jammed into assuming it is a listed device (for bonding shield wires to panel boxes), are we' then saying that these shields do not need to bond directly to a bonding wire, and that using the panelbodies alone are suitable for this supply cable's grounding? Please recall my post noting the supply cable is for a 240V single phase 3 conductor w/shield (armor) system and neither the building's or the panels' EGC is directly attached to the shielding. Given this reiteration, shouldn't that feeder's shield be landed onto the panel's bonding lug (that which also houses the EGC going to the G rod)? And if so, are we saying that the only legitimate use of armor shields (for such a system), disallows it's using the panel to get to the ground lug? Thanks again for pointing out that the feeder's shielding is not the EGC, and for any further afforded reply with respect to my questioning the indirect grounding means which is really what I am dealing with and asking about. I'd send you a picture of supply panel, but you'd moan in disbelief in it having so many other problems. lctrc789 Steven T If I am reading your article right you have a main panel and a sub panel. with the sub panel having A/C cable or M/C cable as the feeds. IMO you should have a fourth wire for a bond between the 2 panles and cannot rely solely on the shield as a ground. Then your sub panel must have a seperate ground bar for the grounds as well as a seperate neutral bar too. If you cannot add a fourth wire then add a ground rod perhaps 2 at 8 feet apart with a bond wire between them for your ground at the sub panel. using the same principle that this is a sub panel with a seperate ground. As far as the bonds or grounds with the A/C cable you would not have to do anything with them to the ground bar other then make sure your A/C cable is attached to the panel correct, and it is bonded to the panel via the connectors and the panel itself is bonded properly. All metallic objects must be bonded together for a proper bond back to the bullseye or the main neutral bar. Steven T. Hi Pat, thanks for the skimmy. As I read it, I understand what you're saying except for the part about "IMO you should have a fourth wire for a bond between the 2 panels and cannot rely solely on the shield as a ground." I see your IMO (in my opinion) as meaning that you agree with my use of the code rqmt [250.130(A)], and that I am correct in interpretating that the AC shield (used for a ground between the two panels) and it's landing simply at the panel bodies which then otherwise relies on the panel's integrity for a reliable and code worthy grounding connection, DOES NOT meet that 250.130(A) and as that rqmt. seem to clearly indicate that "the connection shall be made by bonding the equipment grounding conductor to the grounded service conductor and the grounding electrode conductor". As such, I see this particular system's EGC as being the cable going from the panel to the ground rod (i.e.; the EGC to GEC) and that the panel is not considered as either the EGC or the GSC. And accordingly the GSC must be bonded only to the EGC. In other words this shield must be bonded directly to the EGC, which while it in itself alone is bonded to the panel, the shield itself must be landed at the EGC's terminal and not rely on the panel as the EGC, no? lctrc789 Steven let me rephrase this sorry, If you are relying on the shielding of the M/C or A/C cable alone for the bond to this panel then you have to run the fourth wire as a bond path between the 2 panels. That would be your bonding source then the 4 th wire not the sheilding. If you cannot run a 4th wire then you have an option to ground the system with a ground rod and that would be your grounding system. DO NOT RELY ON THE SHEILDING as your bond between the panels. The fourth wire is your bond if you have an EGC at the main panel no more are required, but the sheilding should not be used as the bond between them. Does this clarify it any better for you. Steven T. PANELS: Each box has it's very own ground rod and each box has it's very own "EGC" (a copper wire) connecting each panel to each ground rod). SERVICE CABLE: A single phase system's direct burial cable (i.e.; a 3 wire conductor with 'aluminum or tinned copper' armor shielding). MY COMMENT: Regardless that there's an EGC and GR installed on and for each panel, I see the code as requiring a "bonding jumper"(a dedicated conductor) and not the panels alone, to connect the shields to each EGC terminal at each respective panel. MY QUESTION: Does not the code [ 250.130(A)] require this scenario's shield to be bonded to more than just the panel body's (e.g.; the shield connected directly to the EGC's terminal)?