Manual Transfer Switch

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BAHTAH

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We have installed a 2" EMT conduit for a 200amp Single-Phase feeder from the service to a Junction box and from the junction box to our sub-panel. We did this because there was talk of a possible generator installation and we wanted to be able to run from the j-box to a xfr switch, back to the j-box and then to the sub-panel. After our conduit installation was comleted, we were told that a manual transfer switch was to be added. The question is, if we run our feeder to the xfer switch and back to the j-box, is there any requirement that the neutral conductor be run to and from the xfr switch since it is not switched in this installation? :?: Thanks Grant
 
Re: neutral

Re: neutral

augie47 said:
I see it widely ignored, but check 300.3(B)
Click to expand...

I was looking more at the requirements for switches and the exception that switch loops do not require a grounded conductor. That may be a stretch for this installation as I cannot find anything specific to this application. Thanks for your input.

Grant
 
lectriclee said:
How do you intend to tie the neutral from the generator the normal power neutral?
Click to expand...

We orginially were going to run (2) 2" conduits to the xfer switch and install the neutral going to and from the xfer switch in each conduit and the generator neutral would be connected as a solid connection in the xfr switch and not switched. Then we thought since the neutral is not switched, why run it into the xfr switch and then back to the j-box? Our thought was to run just one 2" conduit and install the neutral from the j-box to the xfr switch along with the line and load phase conductors. The run is fairly short and the load is calculated at just over 100amps so using a single conduit and (5) 3/0's would work fine. We are trying to determine if the code requires the neutral to run for both the line and load circuits or if we can just use the single neutral thereby allowing us to use a single conduit.
 
Grant
I think you are okay so long as all conductors enter and leave the transfer switch through that same 2" conduit (not including the generator feed). By doing it this way, your switch leg from the main panel cancels itself in that single conduit and the presence of the neutral conductor from the main panel is not needed. So only the generator neutral is required. You should be fine! If anyone out there sees a problem with this installation, please tell us because I do it this way as well!!!
Oh, by the way, rule 300.3(B) states that "all conductors of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained in the same raceway.... " In this case, then grounded conductor (neutral) is not used at the transfer switch and , in my opinion, is not required to be present in the raceway to the switch.
 
Agreed that the neutral must be run from the x-fer switch to the junction box, because the generatot's neutral must hit the panel for the line-to-neutral loads.

I do also wonder if there is any prohibition to running the feeder from the j-box to, and back from, the x-fer switch in a single raceway. I don't see any, but . . .
 
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