Two generators, one MTS... Do the same switching rules apply?

[FAZERS]

A while back, I posted a thread about the configuration of a MTS between two neutral-ground bonded 208Y gensets regarding some details about their grounding conductors. I briefly mentioned with the generator being configured how it was, that it would probably be considered a SDS for this application and that I assumed the MTS would be a switched 4Pole. It's been a minute, but I believe we ended up receiving a 4P MTS from our electrician however with the neutral being non-switched.. and it appears it was installed as such.

It's a trailered, off-grid oilfield application that has a backup generator system for high-availability service. The generators don't ever run at the same time. The application is a bit unusual, if only for the fact it's for two SDS gensets and is never grid-tied or grounded to any external equipment/electrodes on location outside of the grounding rod included with the drop-deck trailer it's on. Both gensets are bonded/bolted to the (metal) frame.

Does the off-grid use, common electrode (frame) or guaranteed mutual exclusion of the gensets running change anything within NEC classification, or will we need to get this resolved pretty quickly?

Attached is a photo of the MTS, neutral unswitched. It looks like we extended the ground conductors to join together at the MTS box despite the neutral-ground bond at the genset terminals.

Thanks,

 

[LarryFine]

The wires through individual holes isn't a good idea.

 

[FAZERS]

The wires through individual holes isn't a good idea.

Why? Higher likelihood of induced field currents?

 

[FAZERS]

Would we be better off using a switched neutral MTS as originally intended or does the application seem admissible?

 

[ron]

The switch in the photo is 3 pole. Only one of the gens can have a N-G bond. Sort of like a utility would have a N-G bond and a non-SDS gen would not have a N-G bond when there is only a 3 pole transfer.