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	Subject - generator to transfer panel connection ajb I recently bought a Generac Generator which came with a pre-wired transfer panel with a 30' run of conduit with the wires. My problem is I have to go about 90 feet to connect from the transfer box to the generator. I was told I may have to use a junction box to splice into the wires to add the extra length. I was also told I may have to go with thicker wires when I connect. I have a few questions. How do I know if I have to go with thicker wires and how much thicker? These are the wires in the conduit: one black 6 AWG type MTW, one Red 6 AWG type MTW, one beige 8 AWG, one green 10 AWG MTW. There are also 4 thin wires about the thickness of a wooden toothpick in colors orange, yellow, brown and blue that are connected into a plastic piece (connector) that is supposed to connect to the female plastic side at the box at the generator. What do I do with these wires to extend them? If I have to make them thicker, how do I get them on the plastic piece that is on the end now? Thanks. Jan Scott Vickrey When you run a wire a long distance you have to take into consideration the resistance and voltage drop of the wire. This done via a voltage drop calculation. However, voltage drop generally doesn't become a factor until you get into lengths longer 100 feet. Was this 30' of conduit flexible? There is a world of considerations here to be cleared up. Is this going to be routed underground? Is this an auto start generator? An electrician is going to be needed to insure the wiring and the warranty of the generator. As for the 4 thin wires. I assume these are control wires for the generator. I'm not comfortable advising you on the proper way to extend these without seeing them. I'm thinking they will have to be replaced with longer wires and the end connectors remade. Maybe the dealer has a kit for this or a longer assemble. Electricman Its been awhile since I installed one of generacs transfer switches but usually if you read the manual they are pretty self explanatary. Like Scott said volt drop isnt a problem till runs are 100 ft. Is this an auto switch? You may consider a different location for your generator if that isnt an option you could contact generac for help.The smaller wires are control wires to start the generator when utility power is interupted so I really dont see a problem with extending them but you should contact generac to see if this voids your warrenty. It sounds like you should probably consult an electrician also so that the installation doesm not violate any codes. Sorry if this doesnt clear anything up but there are alot of things to take into consideration when hooking up any standby systems.Happy Easter He is risen bryan sorry i missed your need for help with the generac generator I own my own electrical company and install many generac and other generators from coleman,briggs,kohler.I dont know if you still need help but if so please write. Scott Vickrey Well, what did you find? jdcastle4ttu I know this thread appears dead, but I joined this board looking for an answer to a question relating to these same transfer panels, so here it is. It is for a 15kW Automatic Standby System. My AHJ seems to think that the generator's built-in sub-panel constitutes a "new service" and therfore should have the neutral/ground bonded. I believe it to be a sub-panel like any other and NOT bonded, especially, as mentioned above, since the flexible conduit included with the generator has 4 wires. Does anyone have an opinion or 2002 code on point here. PS: I too am extending the wire, and I am simply starting over with new conduit and wire cut to the needed length and replacing the ends with the same as the origional. Energreen I'm not familiar with the system or panel you're referring to. However, there's a rule which takes precedence. You must install it according to the manufacturer's instructions. Does the manual indicate how it should be hooked up? If you do it differently from the manufacturer's instructions, you may violate the units UL listing. And the AHJ shouldn't accept such a violation. If the manual supports your position, show it to the AHJ. Ryan_J It is all a function of the transfer switch, and whether or not the nuetral is switched. If it is switched, it is a seperatley derived system, and the rules of 250.30 apply. If it is not switched, the rule of 250.24(A)(5) applies. jdcastle4ttu Thanks Ryan, that hit the nail on the head. I am 99.9% sure that the transfer switch is DPDT and does not switch the neutral. Energreen, I have not yet seen the actual unit, but the manual available on Generac's website only says this: "The standby generator is equipped with an UNGROUNDED neutral. The neutral lug in the transfer swicth is isolated from the switch enclosure." lctrc789 We have to isolate the neutrals or it is switched just as the hots in a two poles two throw switch, the neutral of the generator must be isolated from the main service so the generator becomes a seperately derived system, you can use the same ground system.