Dual Transfer Switches

[bullman]

I have two buildings on my property. Each has its own 200A (240/120 single phase) service and meter. The Power company has a pad mounted transformer on the premises that supplies both buildings. My goal is; to have the ability to connect both buildings to a mobile (trailer mounted) 35KW generator in the event of power lose.

I plan to use a 200A 3 pole service entrance rated manual transfer switch at each building. 3rd pole is for switching the neutral. Each transfer switch will have a receptacle to allow generator connection via 4 conductor mining cable.

If the connection scheme above makes since then my questions are as follows:

Do I need to bond the neutral and ground at the generator?
Do I need to bond the equipment ground from the generator to the transfer switch?
Do I need to bond the transfer switch, meter base and load centers together?
When the transfer switch is in neutral position how is the transfer switch and other enclosures grounded? I assume that is where the proper equipment grounding will come into play.
Since this is a mobile generator, Will I need to have a ground rod connection where the generator is parked?
Will this be a separately derived system?
Is there such a thing as a manual transfer switch with overlapping neutral connection to avoid the arcing at engagement? I know they have automatic ones that can do this.

Thanks

 

[tortuga]

Do I need to bond the neutral and ground at the generator?

No, bond at the service panel.

Do I need to bond the equipment ground from the generator to the transfer switch?

Yes

Do I need to bond the transfer switch, meter base and load centers together?

yes

When the transfer switch is in neutral position how is the transfer switch and other enclosures grounded? I assume that is where the proper equipment grounding will come into play.

There should be no off or neutral position. Its a on-on switch.

Since this is a mobile generator, Will I need to have a ground rod connection where the generator is parked?

No

Will this be a separately derived system?

No

 

[bullman]

Thanks for the replay. It sounds like you are in agreement with both transfer switches having switched neutrals. I need to clarify that I am using service rated 200 amp DTDT safety switches as the transfer switches, so there is an instant where there is no connection to the utility company or the generator. Does this fact change any of the answers given to my questions?

 

[tortuga]

I typically float the neutral at the generator, then I use a two pole transfer switch at each building.
I usually use a 'breaker interlock kit' in the service panel,
For portable or trailer mounted generators I use a California Standard CS6375 twist lock inlet 50Amp 125/250V .
Bond an ECG to the frame of the generator.