Phillip Posted April 7, 2007 Report Share Posted April 7, 2007 Take a look at this panel and tell me what you see. Download Attachment: 04-06-07 074.jpg 131.62 KB Download Attachment: 04-06-07 076.jpg 94.57 KB Quote Link to comment Share on other sites More sharing options...
Jim Katen Posted April 7, 2007 Report Share Posted April 7, 2007 Take a look at this panel and tell me what you see. I see an MLO subpanel with what seems to be an EGC landing on the neutral terminal bar instead of the grounding terminal bar. Inattentive electrician? - Jim Katen, Oregon Quote Link to comment Share on other sites More sharing options...
Brian G Posted April 7, 2007 Report Share Posted April 7, 2007 Aside from what Jim said, I see only 3 equipment ground wires for 8 single pole breakers. [:-?help] I also see that you need a camera with better macro features for close-ups. [] Brian G. Certfied Smart-A** [:-paperba Quote Link to comment Share on other sites More sharing options...
Jim Katen Posted April 7, 2007 Report Share Posted April 7, 2007 Originally posted by Brian G. . . . I also see that you need a camera with better macro features for close-ups. [] I thought the wiring was just fuzzy. - Jim Katen, Oregon Quote Link to comment Share on other sites More sharing options...
ozofprev Posted April 7, 2007 Report Share Posted April 7, 2007 If that's a subpanel, it shouldn't be. Doesn't look like a floating neutral. Originally posted by Jim Katen I see an MLO subpanel with what seems to be an EGC landing on the neutral terminal bar instead of the grounding terminal bar. Inattentive electrician? - Jim Katen, Oregon Quote Link to comment Share on other sites More sharing options...
Brian G Posted April 7, 2007 Report Share Posted April 7, 2007 Originally posted by ozofprev If that's a subpanel, it shouldn't be. Doesn't look like a floating neutral. I can't see well enough to be sure whether there might be a bonding screw on one of those neutral bars, but all of the mounting hardware looks to be plastic (oh excuse me...resin). The jumper is defintely insulated. Brian G. Resin-ating With My Clients [] Quote Link to comment Share on other sites More sharing options...
chicago Posted April 7, 2007 Report Share Posted April 7, 2007 Is it the fuzzy picture or are a couple of those grounds running past the bar?. Quote Link to comment Share on other sites More sharing options...
Phillip Posted April 8, 2007 Author Report Share Posted April 8, 2007 It is a sub panel. I should of turn off the flash when I took the photo The neural is floating. yes the grounds ends run past the bar. The EGC runs to the water lines just like the exterior panel does. The interior panel has been replaced. Most of the house has a 2 wire system. Quote Link to comment Share on other sites More sharing options...
ozofprev Posted April 8, 2007 Report Share Posted April 8, 2007 So that tie bar at the top of the bars is not connecting the bars? Originally posted by Phillip It is a sub panel. I should of turn off the flash when I took the photo The neural is floating. yes the grounds ends run past the bar. The EGC runs to the water lines just like the exterior panel does. The interior panel has been replaced. Most of the house has a 2 wire system. Quote Link to comment Share on other sites More sharing options...
hausdok Posted April 8, 2007 Report Share Posted April 8, 2007 Hi, No, it connects those two buses, which are themselves isolated from the panel by resin mounting blocks. The installation would have been fine if a 4-wire cable had been used and the equipment grounding conductor was connected to the mounting lug at the top of that equipment grounding bus that's almost concealed by the left bank and that heavy grounding conductor were eliminated. That looks like a newer panel, which means that the electrician screwed up. It's not unusual to see that on old panels but on a newer one? Uh uh. The NEC does not recognize running a separate equipment grounding conductor outside the feeder or in a separate path to that sub-panel, so that heavy bare grounding conductor has to go. It's gonna be costly to pull a new 4-wire feed to that panel. ONE TEAM - ONE FIGHT!!! Mike Quote Link to comment Share on other sites More sharing options...
chicago Posted April 8, 2007 Report Share Posted April 8, 2007 That must be why conduit is better than NMC.Knew there had to be a reason Quote Link to comment Share on other sites More sharing options...
ozofprev Posted April 8, 2007 Report Share Posted April 8, 2007 Correct. There is no floating neutral. If the bars are tied - as they are - then a separate ground bus is needed. This should not be a subpanel. I think people mistakenly believe that an isolated panel equates to floating neutral. Big mistake. And you are right Mike, it will require some $$$. Originally posted by hausdok Hi, No, it connects those two buses, which are themselves isolated from the panel by resin mounting blocks. The installation would have been fine if a 4-wire cable had been used and the equipment grounding conductor was connected to the mounting lug at the top of that equipment grounding bus that's almost concealed by the left bank and that heavy grounding conductor were eliminated. That looks like a newer panel, which means that the electrician screwed up. It's not unusual to see that on old panels but on a newer one? Uh uh. The NEC does not recognize running a separate equipment grounding conductor outside the feeder or in a separate path to that sub-panel, so that heavy bare grounding conductor has to go. It's gonna be costly to pull a new 4-wire feed to that panel. ONE TEAM - ONE FIGHT!!! Mike Quote Link to comment Share on other sites More sharing options...
hausdok Posted April 8, 2007 Report Share Posted April 8, 2007 Hi Bob, I know very little about conduit because I hardly see it. If that cable were fed with a 3-wire feed through conduit I suppose you could use the conduit itself as the grounding conductor back to the main panel but it would be almost impossible, wouldn't it, to push a fishtape back through a conduit past 3 wires, in order to pull a 4th conductor - saying that's what you wanted to do instead of using the conduit itself as the grounding path? ONE TEAM - ONE FIGHT!!! Mike Quote Link to comment Share on other sites More sharing options...
Jim Katen Posted April 8, 2007 Report Share Posted April 8, 2007 Originally posted by hausdok Hi, No, it connects those two buses, which are themselves isolated from the panel by resin mounting blocks. The installation would have been fine if a 4-wire cable had been used and the equipment grounding conductor was connected to the mounting lug at the top of that equipment grounding bus that's almost concealed by the left bank and that heavy grounding conductor were eliminated. Look more carefully. That is a 4-wire feeder. The two hots go to the main lugs. The white neutral goes to the right neutral terminal. The bare grounding wire snakes along the bottom of the enclosure and connects to the grounding bar. It connects at the bottom of the bar. As far as I can see, the only problem here is that the heavy wire that leads to the water pipe is connected to the neutral terminal bar instead of the grounding terminal bar. That looks like a newer panel, which means that the electrician screwed up. It's not unusual to see that on old panels but on a newer one? . . . For the record, it doesn't matter. The rules haven't changed. The neutral was supposed to be floated at least as far back as 1947. - Jim Katen, Oregon Quote Link to comment Share on other sites More sharing options...
ozofprev Posted April 8, 2007 Report Share Posted April 8, 2007 Good eyes, Katen. That is a four wire. But the tie bar still has to go, yes? Quote Link to comment Share on other sites More sharing options...
hausdok Posted April 8, 2007 Report Share Posted April 8, 2007 Wow, You have got good eyes Jim. I had to open that thing is PhotoShop, blow it up and tweak the contrast to see that aluminum conductor against that shiny galvanized background. Sorry, I stand corrected. Still, if you've got the 4th conductor, why would you even want that grounding conductor, which is connected to the water piping, when you've got the grounding conductor as your path? ONE TEAM - ONE FIGHT!!! Mike Quote Link to comment Share on other sites More sharing options...
Jim Katen Posted April 8, 2007 Report Share Posted April 8, 2007 Originally posted by ozofprev Good eyes, Katen. That is a four wire. But the tie bar still has to go, yes? No. There's no reason for it to go. The tie bar just connects the two neutral conductors. The whole neutral shebang is insulated from the panel enclosure. The grounding terminal bar is bonded to the enclosure and it handles the few EGCs that land in this panel. - Jim in Oregon Quote Link to comment Share on other sites More sharing options...
Jim Katen Posted April 8, 2007 Report Share Posted April 8, 2007 Originally posted by hausdok . . . Still, if you've got the 4th conductor, why would you even want that grounding conductor, which is connected to the water piping, when you've got the grounding conductor as your path? ONE TEAM - ONE FIGHT!!! Mike If the sub-panel's in the same building as the service panel, there's no need for the water-pipe-conductor but I don't see any particular problem with it either. - Jim Katen, Oregon Quote Link to comment Share on other sites More sharing options...
hausdok Posted April 8, 2007 Report Share Posted April 8, 2007 Hmmm, Okay, maybe I'm just cornfoozed then. I based the above on what I'd read in Hansen's book. Guess I need to go back and re-read it again, and again, and again. Don't know why, but even after 11 years I still struggle with understanding electrical systems and grounding and bonding paths. It still confuses the hell out of me. Sigh. OT - OF!!! M. Quote Link to comment Share on other sites More sharing options...
Brian G Posted April 8, 2007 Report Share Posted April 8, 2007 Originally posted by Jim Katen If the sub-panel's in the same building as the service panel, there's no need for the water-pipe-conductor but I don't see any particular problem with it either. I had a thread about this somewhere, where I was trying to figure out if the code allowed a separate grounding electrode on a sub panel in the same building as the service equipment (needed or not). It does, so long as it's bonded with the other grounding system. If the sub panel is in a separate building the grounding electrode is required, whether it needs a 3 or 4 wire arrangement, and also must be bonded to the other grounding system. Gary, are you missing the small equipment ground bar half-hidden by the left-hand row of breakers? Brian G. Bonded...James Bonded [:-paperba Quote Link to comment Share on other sites More sharing options...
Phillip Posted April 8, 2007 Author Report Share Posted April 8, 2007 The panel is inside the home as the exterior panel is on. My main concern is the large copper wire on the neutral bar going to the water pipe. Thanks for the input from everyone. It is the first time I have seen it this way. To me there is no need for the large copper wire. Quote Link to comment Share on other sites More sharing options...
chicago Posted April 8, 2007 Report Share Posted April 8, 2007 HI Mike jumping in a little late now that the TIJ electrical guru has figured it out. My thinking actually was to pull a fourth wire and yes you maybe right about the difficulty of pulling it through depending on the gauge wire and diameter of conduit.Guess thats why they make the wire lube.Personaly I used to just yank it all out tying it to the old stuff , half the time. Because in the city the old covering would deteriorate soon as you touched it. Quote Link to comment Share on other sites More sharing options...
ozofprev Posted April 9, 2007 Report Share Posted April 9, 2007 Brian, Thank you!!! I thought I was losing my mind (not a huge loss, but still). I knew Katen wasn't gonna flub, so I was really stumped on why that tie bar was not the elephant in the room. NOOOO I did not see that little ground bar. Thanks, it's all good now. This is a great bunch of HIs. Originally posted by Brian G. Originally posted by Jim Katen If the sub-panel's in the same building as the service panel, there's no need for the water-pipe-conductor but I don't see any particular problem with it either. I had a thread about this somewhere, where I was trying to figure out if the code allowed a separate grounding electrode on a sub panel in the same building as the service equipment (needed or not). It does, so long as it's bonded with the other grounding system. If the sub panel is in a separate building the grounding electrode is required, whether it needs a 3 or 4 wire arrangement, and also must be bonded to the other grounding system. Gary, are you missing the small equipment ground bar half-hidden by the left-hand row of breakers? Brian G. Bonded...James Bonded [:-paperba Quote Link to comment Share on other sites More sharing options...
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