Kyle Kubs Posted June 13, 2008 Report Posted June 13, 2008 Sorry, my brain is fried and I'm just tired of looking through books. Today's panel started out as the sole, main panel. 2006 they added a propane powered generator on an auto start switch and moved all the geny powered circuit feeds to the lower panel through a close nipple between the two, odd thing is they left all the circuit neutrals and grounds hooked up to the bus bars on the main panel. Now the whole thing is a work of art obviously done by somebody smarter than me, it's got it's Twp. sticker and all but it just doesn't sit right with me. I feel like something somewhere requires the neutrals and grounds to originate in the same panel as the feeds but maybe I just have a loose neutral today cause I can't figure out why. Anyone? Image Insert: 1360.34 KB
Brandon Whitmore Posted June 13, 2008 Report Posted June 13, 2008 Kyle, I am racking my brain trying to figure out why this would be a problem and can not. Now for the code guru's answers. Sorry-- this wasn't any help.
hausdok Posted June 13, 2008 Report Posted June 13, 2008 It's because power generated by the gentran goes through those breakers in the lower box to where they are spliced into the appropriate circuits in the upper panel downstream from their breakers. From there, power goes through those circuits and must return to earth via the grounded conductors (neutrals) on those circuits. Those end where they should on the neutral bus in the upper panel. The neutral and ground bars in the lower panel are bonded with that copper cable to the bonded bar in the upper panel. I don't see an issue with it. ONE TEAM - ONE FIGHT!!! Mike
Speedy Petey Posted June 13, 2008 Report Posted June 13, 2008 It certainly IS a violation, only I don't have time to look it up right now. Even panels that come with generators and have leads to splice the branch circuit have both hot and neutral leads for each circuit.
Billy_Bob Posted June 13, 2008 Report Posted June 13, 2008 So far as codes go, there is the "letter of the law" and then there is the "intention" behind a rule. With the NEC it is safety and fire prevention basically. Codes aside, I can't imagine any potential safety or fire danger with the way these panels are wired. Part of my thinking here is that the two panels are mechanically and electrically attached to each other as well as to the wall. This is a different situation than say if you had a sub panel some distance away. In that case you have central point of ground issues and potential problems with loss a conductor in the cable if someone drilled through it or whatever.
Brian G Posted June 13, 2008 Report Posted June 13, 2008 I think it's exactly the same as having a sub panel, and distance means nothing in those cases (as covered in a couple of recent threads). I can't cite the NEC offhand, but I'd bet you can't have the overcurrent/feed devices in one panel and the equipment grounds and neutrals terminated in another (for the same circuits). That's nuts. Brian G. Move One Side, Move the Other [:-magnify
Chad Fabry Posted June 13, 2008 Report Posted June 13, 2008 All wiring for a circuit must be run together
ghentjr Posted June 14, 2008 Report Posted June 14, 2008 Originally posted by Kyle Kubs Sorry, my brain is fried and I'm just tired of looking through books. Today's panel started out as the sole, main panel. 2006 they added a propane powered generator on an auto start switch and moved all the geny powered circuit feeds to the lower panel through a close nipple between the two, odd thing is they left all the circuit neutrals and grounds hooked up to the bus bars on the main panel. Now the whole thing is a work of art obviously done by somebody smarter than me, it's got it's Twp. sticker and all but it just doesn't sit right with me. I feel like something somewhere requires the neutrals and grounds to originate in the same panel as the feeds but maybe I just have a loose neutral today cause I can't figure out why. Anyone? Image 751_EasyDay.JPG[/img] 1360.34 KB Lotsa comments, many not accurate. My two cents. The street power is fed from the right side of the main panel into the generator control. During normal power times the flow goes through to the lower (sub) panel. The generator control automatically cuts off street power when the generator activates, and feeds power to the lower panel. The lower panel is 4 wire as a sub panel should be. When street power returns the generator shuts down and the feed to the lower sub panel is restored from the main panel. No magic, just follow the wires.
Kyle Kubs Posted June 14, 2008 Author Report Posted June 14, 2008 Originally posted by ghentjr Originally posted by Kyle Kubs Sorry, my brain is fried and I'm just tired of looking through books. Today's panel started out as the sole, main panel. 2006 they added a propane powered generator on an auto start switch and moved all the geny powered circuit feeds to the lower panel through a close nipple between the two, odd thing is they left all the circuit neutrals and grounds hooked up to the bus bars on the main panel. Now the whole thing is a work of art obviously done by somebody smarter than me, it's got it's Twp. sticker and all but it just doesn't sit right with me. I feel like something somewhere requires the neutrals and grounds to originate in the same panel as the feeds but maybe I just have a loose neutral today cause I can't figure out why. Anyone? Image 751_EasyDay.JPG[/img] 1360.34 KB Lotsa comments, many not accurate. My two cents. The street power is fed from the right side of the main panel into the generator control. During normal power times the flow goes through to the lower (sub) panel. The generator control automatically cuts off street power when the generator activates, and feeds power to the lower panel. The lower panel is 4 wire as a sub panel should be. When street power returns the generator shuts down and the feed to the lower sub panel is restored from the main panel. No magic, just follow the wires. While I appreciate the effort, that was all totally understood and not at all the question I was asking... While I don't think it is a big issue at all, especially in this configuration, I'm fairly certain it is technically wrong. Now that I'm not as sleep deprived as I was yesterday I'm beginning to be able to wrap my head around the mechanics of why I think it's wrong. The first thing that came to mind is, as Chad said, all members of a circuit must be run together. While this really applies more to cable and conduit applications it certainly can apply here as well. Main issue with it being the imbalance of the magnetic fields, without the neutrals to cancel the field from the feeds this leaves a potential for induction heating, albeit very, very small in this case. Keep in mind, I'm saying this as a point of discussion, not that I'm certain I'm right defending my position. Any and all opinions are welcome. Where is the almighty Katen when you need him... or Mr. Abernathy? I hate having to call out stuff like this. It's so minuscule, yet on a technical note just wrong, I think. My brain is hurting again.
Inspectorjoe Posted June 14, 2008 Report Posted June 14, 2008 I don't think that's wrong. Although I have a manual transfer switch, it's wired the same way. When first I went to install it, I looked at the wiring diagram, and thought, "no way, this can't be right". I did some research on the net, ruminated on it for a few days, then took the plunge and did it. The generator panel is fed from a two pole breaker in the main panel. The branch circuit hots are disconnected from the breakers in the main panel and wire nutted to pigtails that connect to the breakers in the generator panel. The two panels are bonded. The only neutral in the generator panel is from the generator as it passes through the enclosure and on to the neutral/ground bus bar in the main panel. Outside Inside Installation manual
Speedy Petey Posted June 15, 2008 Report Posted June 15, 2008 Originally posted by ghentjr Lotsa comments, many not accurate. Such as ???
Speedy Petey Posted June 16, 2008 Report Posted June 16, 2008 Originally posted by Inspectorjoe I don't think that's wrong. Although I have a manual transfer switch, it's wired the same way. It is certainly NOT wired the same way. What you have is a "Gen-Tran" type panel. The circuits are fixed and that is NOT a sub-panel. What the OP has IS a sub-panel, and the neutrals of the circuit MUST originate from the same panel as the circuit conductors.
Tom Raymond Posted June 16, 2008 Report Posted June 16, 2008 I think this is a case when the installation manual should be required to determine if this is a correct installation or not. This is a transfer switch after all, not the typical sub panel we are accustomed to. I'll bet the AHJ that blessed it had to read the manual. Speedy, why are you so convinced that the automatic switch is wrong when the manual switch is obviously not? A switch is a switch, doesn't matter who trips it. Bottom line is this is a set up we will be seeing more and more, we should take the time to educate ourselves and stop making WAG's. Tom If all else fails, read the directions!
Chad Fabry Posted June 16, 2008 Report Posted June 16, 2008 I'll bet the AHJ that blessed it had to read the manual. Tom, I do PV installation inspections. It is not even close to being safe to assume that an AHJ takes the time to understand how new or unusual installations are to be installed so that they're compliant and safe. It's been my experience that, in fact, it's mostly opposite.
Tom Raymond Posted June 16, 2008 Report Posted June 16, 2008 That was kinda my point, the AHJ either did his job and read the manual (pretty funny, huh?) or passed it on looks alone. Either way I'm sure he had no idea how it was supposed to be wired. I don't think most of the people who have responded do either. I see these systems popping up all over around here, and when I finally run into one on an inspection I will have to punt, or break down and read the manual so I know what the hell I'm looking at. We HI's call ourselves professionals, If we were we would read the flippin' manual and learn something. Tom Aw, forget the manual, it's only manufacturers opinion anyway[]
Speedy Petey Posted June 17, 2008 Report Posted June 17, 2008 Originally posted by Tom RaymondSpeedy, why are you so convinced that the automatic switch is wrong when the manual switch is obviously not? A switch is a switch, doesn't matter who trips it. It has absolutely nothing to do with automatic or manual. It has to do with how they are wired. A "Gen-Tran" type panel is a fixed wired panel. You cannot add circuits or change the sizes of the existing circuits. Also, the breakers in the existing panel are being used. The little plunger breakers in the transfer panel are ONLY for when the circuit is on the "GEN" setting. The panel in the OP's situation IS a sub panel with it's OWN branch circuit breakers.
Inspectorjoe Posted June 17, 2008 Report Posted June 17, 2008 Originally posted by Speedy Petey It has absolutely nothing to do with automatic or manual. It has to do with how they are wired. A "Gen-Tran" type panel is a fixed wired panel. You cannot add circuits or change the sizes of the existing circuits. Also, the breakers in the existing panel are being used. The little plunger breakers in the transfer panel are ONLY for when the circuit is on the "GEN" setting. The panel in the OP's situation IS a sub panel with it's OWN branch circuit breakers. Uh, Speedy, they're BOTH sub panels with their OWN branch circuit breakers. Did you look at the pictures? Did you look at the installation manual? Here it is again, in case you didn't see it before: Gen-Tran installation manual You certainly can add circuits or change the size of existing circuits. Mine came with four 15 amp and four 20 amp Siemens breakers. I configured it with eight 20 amp breakers, the other four being Square D. Here are the breakers the panel accepts: â⬢ Siemens QP, QT, QPH, HQP, QPF, QPHF, QFP, QE, QEH â⬢ Westinghouse Series BD, BR, BQ, GFC â⬢ Challenger Type A, C, HAGF â⬢ Square D Series HOM â⬢ GE Series THQL The breakers in the original panel are no longer used, as I mentioned in post #10: "The branch circuit hots are disconnected from the breakers in the main panel and wire nutted to pigtails that connect to the breakers in the generator panel." The breakers in the Gen-Tran panel are the ONLY breakers for those circuits and are used under both line and generator power.
Kyle Kubs Posted June 17, 2008 Author Report Posted June 17, 2008 InspectorJoe, Thanks for taking the time and trouble to post the pics and manual, it was helpful. Still not sure why the manual allows it this way but it's something. I tried to get the manual for what I am dealing with, a Kohler unit, but their web site is not what I would call user friendly... Originally posted by Speedy Petey Originally posted by Tom RaymondSpeedy, why are you so convinced that the automatic switch is wrong when the manual switch is obviously not? A switch is a switch, doesn't matter who trips it. It has absolutely nothing to do with automatic or manual. It has to do with how they are wired. A "Gen-Tran" type panel is a fixed wired panel. You cannot add circuits or change the sizes of the existing circuits. Also, the breakers in the existing panel are being used. The little plunger breakers in the transfer panel are ONLY for when the circuit is on the "GEN" setting. The panel in the OP's situation IS a sub panel with it's OWN branch circuit breakers. Pete, While I do agree with you that in my situation the neutrals and grounds should originate in the sub panel, I disagree that the set up Joe is presenting is different and NOT a sub panel. I have seen his setup before but just made up by an electrician using a common breaker fed panel with the lockout that only allows one of the disconnects to be on. Joe's gen panel is taking power from a breaker on the main panel and using a four wire feed. It is a sub panel. The power for the generator circuits is fed through the breakers in that sub panel. I don't see where you think the breakers in the existing panel are being used. The existing main panel feeds the sub panel, the sub feed the circuits connected to it through it's breakers, regardless of the whether the panel is being fed from the main panel or from the generator. The feeds from the breakers in the sub are wire nutted to the original leads in the main panel... Also not sure why you are saying the panel is "fixed". They are just breakers...snap in and out like anything else. Looks like it comes as kind of a pre-assembled kit that will handle most common setups, nothing you couldn't make up yourself with the right parts, but it is still just a loadcenter. Chad, I agree wholeheartedly and I don't expect you or anyone to believe it but I was on site at a job just recently where the AHJ came in told the contractor it was wrong and then picked up the manual off the boiler and showed him where the manufacturer called for the drain T in the vent pipe he didn't install and said wasn't needed. I'm sure it will never happen again.
Speedy Petey Posted June 17, 2008 Report Posted June 17, 2008 OK hold it! Looking at it again I see that I am totally wrong about Joe's panel. I only looked at that pic once and quick and saw those little watt meters. I never noticed that they were actual breakers. Sorry guys. Like I said though, I have seen pre-wired panels like this where each circuit has a hot AND a neutral tail that gets spliced into the main panel's circuits. There are two hots, a ground AND a neutral that feed the generator panel. I just did a customer supplied Generac unit that was this way.
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