225.30-31 questions

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RD35

RD35

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Bloomington, Indiana
New shop building next to existing home. New feeder from panel at existing home to new panel in new building. Easy enough so far right? So, I also need to run a 12/3 W/G out to the new building to operate lights at the building switchable from both the new building and the existing house via 3-way switches.

Question #1: Is this compliant with 225.30 paragraph #2?

I will also be installing two sets of feeders from the new building to the existing home for standby generator power. One feeder circuit will feed power to an automatic transfer switch for a padmounted generator at the building. The other feeder will connect to a manual transfer switch so that a portable generator can be connected at the new shop building in the event the pad-mounted generator fails. (Actually, the pad mount generator is not in the budget yet, but homeowner already has the manual switches and portable generator...and wants to keep them for back-up...of the back-up!)

Question #2: Is there a violation of 225.30 in this instance?

When the building feeder enters the new building, its first stopping point will be an automatic transfer switch that is equipped with a small accessory handle which can be used to manually move the switch from utility to generator.

Question #3: Would this suffice as an acceptable means of disconnect for the feeder entry to satisfy 225.31? (otherwise will need to purchase a more expensive service entrance rated switch with utility circuit breaker disconnect)
 
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For Question 1, if you plan to run a feeder from house to a panel in the new building and also run a branch circuit from the house to a light in the new building, then I think this would violate the "feed a building only once" rule within 225.30. But if the light is powered from the new building's panel, and if the wires running back to the house are essentially for switching only, then I think you would satisfy the second paragraph of 225.30.

For Questions 2 and 3, I don't understand your description. Question 1 tells me there is a standard utility service to the house, and you are adding a feeder from the house panel to the new building. But Questions 2 and 3 seem to be saying that that feeder will land on a transfer switch, not directly on the building's panel. OK so far. So the load side of the ATS can get power either from the house panel or the pad-mounted generator. If it only serves the new building, I would call that OK. But the questions are implying that it somehow provides backup power to the house. I don't get how you plan to wire that. If the utility is providing power, then you are going from the utility, to the house panel, to the feeder, to the ATS, and somehow back to the house. This makes no sense.

Can you clarify your intent?
 
Thank-you charlie b for looking at this! After reading your response I realized I was not accurate in my initial description for this project. As for the branch circuit for switching lights, yes I will be sure to feed it from the new shop building. Now as for questions 2 and 3, I looked at the line diagram I drew up a few weeks ago....and, again, was not accurate on my description in the OP. So, I am submitting this line diagram for your viewing pleasure. Please don't hurt yourself by laughing too hard as you look this over. The ATS (automatic transfer switch) at the shop building is the first means of disconnect once the utility (normal power) feeder enters the building. Just wondering if the transfer switch itself can be considered a disconnecting means without having a utility feed breaker (SE Rated).
House One-Line Diagram.jpg
Now it's confession time! This diagram is for my house. Just purchased this home. It has no garage or shop. Those will be brand new. It has a 200A service mounted on the existing house. I'm planning to add a 2-car garage (attached) and the new shop (70 feet away). I will remove the 200A service from the house and convert the current house panel to a sub panel. That panel will be fed from lugs in a new 200A panel in the garage. New shop will get its own dedicated 200A feed from a 2nd 200A breaker located at the new service entrance in the new 2-car garage. So, I currently have two 3P,DT, 200A manual transfer switches (MTS) that I will be installing per the diagram. My wife wants an automatic system for when I am away on travel. This means I will need two ATS units as well. (Yes, total of four transfer switches...I know it sounds nuts) Since I am getting back in the business of designing electrical systems, I wanted to install both types of switches so that I can show clients how each works...and what is involved to install each type. My concern is that I am, somehow, creating a violation 225.30, 31, or 32 with this system.

Any inputs, opinion, good or bad, are much appreciated. Thanks in advance folks...and again thank-you charlie b for your initial look at my errant description.
 
RD35 said:
Trying to get the photo of this diagram to load with higher detail. Won't go for some reason.
Click to expand...
The reason is likely to be the forum's limit on file size. Can you upload the image to a photo hosting web site, and post a link to its location? If you can't do that, then send me a PM. I will send you my email address. You can then send me the photo in as high a resolution as you can, and I will post it on my photo web site. I could not read the image you posted here, so I don't understand your proposed installation.

That said, I believe you can get an ATS that does have the ability to serve as a disconnecting means. But if the "owner" already has one, it's a question of fact as to whether that ATS has this feature.

 
RD35 said:
Now it's confession time! This diagram is for my house. Just purchased this home. It has no garage or shop. Those will be brand new. It has a 200A service mounted on the existing house. I'm planning to add a 2-car garage (attached) and the new shop (70 feet away).
Click to expand...
I see from your profile that you are an EE, and not an electrician. Forum rules do not allow us to assist a person who is not an electrician in the performance of their own electrical installation work. So please tell me that you are going to have an electrician perform the work that you are discussing in this thread. Otherwise, it will have to be closed before you get your answers.

 
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