MJM
I am reviewing the wiring diagram for the 200 Amp generac transfer switch. I see in the diagram that it only shows 3 wires coming into the switch from the utility (2 hot - 1 neutral - no ground). My service panel has 4 wires (2 hot, 1 neutral and ground). I would think that all 4 wires would need to be moved from the service panel to the transfer switch. Am I missing something or do I "NOT" bring the ground wire from the utility service entrance cable into the transfer switch? I also see in the diagram that there is a jumper between the neutral bar and ground bar in the transfer switch. Can anyone spec the wire size of the jumper? 16KW with 200amp transfer switch. 
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Brian Baughman
The service rated ATS is designed to be installed as service equipment between the existing meter socket enclosure and the existing service panelbaord, with the downstream panelboard being re-wired as a subpanel .   Since you have a 4 wire feeder in distribution panelboard, you have a subpanel and not a service panel.  I'm guessing that your home has the main service disconnect within or adjacent to the meter socket enclosure.  Service entrance conductors do not utilize an equipment grounding conductor, feeder conductors are required to have either an equipment grounding conductor or a supply-side bonding jumper.

You can still use the service rated disconnect, however the green bonding jumper between the grounded conductor terminal bar and the equipment grounding conductor terminal has to be removed.
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MJM
Thank you for the reply. You are correct, my main service disconnect is adjacent to my meter, the wiring then travels from the disconnect across my homes attic and down into my panel. I did find another diagram that shows my situation, 4 wires coming from my disconnect into the transfer switch, 2 hot legs into n1 and n2, 1 leg to the neutral bar and 1 to the ground bar. It then shows the wiring from the transfer switch to my panel (again 4 wires) and yes, the diagram does not show a jumper from neutral to ground in the transfer switch like the other diagram i referred to initially. Once again thanks for the clarification.
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Cobranut
MJM,

The reason for the outside disconnect is the length of feeder between that and your panel.
The feeder is usually not protected by an over-current device, so if it's over a certain length, code requires your setup.

Your installation may be simplified by mounting your SE rated transfer switch in place of your outside disconnect.
This would eliminate the need for your generator feeder to enter the house, which may greatly simplify the install.
The utility breaker in the switch would then be your service disconnect.
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MJM
Cobranut wrote:
MJM,
I have to set the generator on the side of my home where my current sub panel is (opposite side of the home from where my meter and disconnect is). My HOA had a rule in place for years that no generators were allowed. The rule was finally overturned, but the new modified rule is that the generator can not be set on the side of the home that adjoins the neighbors bedroom space. If there's no issue with bringing my utility feed into the transfer switch, then that's what I'll do. The bonus for me is that my gas supply is less than 10 feet from where I'll set the generator. I guess I'll have to ask the question "is there an issue with having the 2 disconnects and hopefully I'll be able to land my service cable in the transfer switch panel", I'm not sure what the largest size wire that the lugs will accept in the switch. My past experience (4 generators installed), was always with prewired dedicated circuit transfer switches and service panels with the disconnect in the panel. My current situation is new to me. The generator and switch will be delivered tomorrow, so I guess I'll find out. Thanks for the reply.



The reason for the outside disconnect is the length of feeder between that and your panel.
The feeder is usually not protected by an over-current device, so if it's over a certain length, code requires your setup.

Your installation may be simplified by mounting your SE rated transfer switch in place of your outside disconnect.
This would eliminate the need for your generator feeder to enter the house, which may greatly simplify the install.
The utility breaker in the switch would then be your service disconnect.
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Cobranut

MJM,

Wow, no generators.  That's quite a restriction.  Glad they finally came to their senses.

The 200a transfer switch lugs will accept at least 4/0 cable.
There should be no problem with doing it that way, and yes, it does make sense in your application.
I was just pointing out the possibility in case you hadn't thought of it. 😊

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MJM
Cobranut wrote:

MJM,

Wow, no generators.  That's quite a restriction.  Glad they finally came to their senses.

The 200a transfer switch lugs will accept at least 4/0 cable.
There should be no problem with doing it that way, and yes, it does make sense in your application.
I was just pointing out the possibility in case you hadn't thought of it. 😊

So yesterday I may have been thrown a curveball on my install. One of my neighbors son is an electrician. He stopped by by yesterday to give me some liquidtite conduit that he picked up for me. He was checking out my generator and switch that was delivered to my home on Friday. He installed the identical generator at his parents home about a year ago. He says to me "I think you're going to have a problem with your installation", I ask why, and he says "I don't think the inspector is going to let you have 2 disconnects". He also said if he won't let me have the 2 disconnects, I can replace my present disconnect with the transfer switch. My situation as discussed above is my meter and disconnect are on one side of my home and my sub panel is on the other. My intention was to install the service rated transfer switch adjacent to the sub panel and the generator would be set directly outside that location. I'll guess I'll be discussing my issue with the inspector on Monday. If he won't allow the 2 disconnects, I'll probably just bite the bullet and purchased the 200 amp non service rated switch to make things easy. All I can say is keep an eye out in the generac generator classifieds at the bottom of the page for 1 brand new 200 amp transfer switch. 

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Cobranut
I assume your current disconnect is a breaker and not just a switch. 

You should have no trouble getting enough out of your SE rated switch to pay for a non SE switch. 
In fact your dealer may trade. 
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