300A UG Service with two 200A ATS Generac

[pkelectrical]

Has anyone done similar installation weather 300 or 400A UG service with two 200A ATS Generac?

You use one ATS to get power from generator and the other is just connected through 23& 194 low voltage from the 1st ATS? do you run wire for the 0 Ground too or just 23 & 194. Can't seem to find answer for this anywhere.

 

[LarryFine]

Yes, I've done a few dual-ATS installs. If I remember correctly, the ground is required for the load-shedding in the slave ATS to operate. It can't hurt to run it anyway.

 

[electrofelon]

Do you really need 2 ATS's? How big is the genny?

 

[LarryFine]

Do you really need 2 ATS's?

It's an alternative to relocating circuits to create a single gen-fed panel.

Added: Above presumes there are two panels.

 

[Chamuit]

Why don't you go from generator to 300A/400A ATS and then tie the panels and meter into the ATS?

Generac makes those. This is a Kohler but you should get the idea.

 

[pkelectrical]

Why don't you go from generator to 300A/400A ATS and then tie the panels and meter into the ATS?

Generac makes those. This is a Kohler but you should get the idea.

View attachment 21771

The 400A or 300A ATS from Generac costs 2.7k, while 1 200A ATS is around 0.7k. If I use two 200A ATS it will cost 1.4k vs 2.7k
I know Briggs and Stratton makes 400A split 200A ATS where you can tie two 200A distribution panels directly into the ATS, eliminating the need for trough, it costs around 1.7k, but the customer wants Generac

 

[Chamuit]

So, your T1 circuit and the voltage sensing can come from one of the ATS', but your control would have to go to both (23 & 194? can't remember the numbers) to make sure they both switched. SMMs would work automatically as the sense voltage and frequency. Run the generator circuit to both ATS'.

 

[GentekPower]

The only wires you'll need in your 2nd 'slave' switch for controls are the 23 and 194 wires. The T1 is nothing more than the A phase of the load side of the switch and the load shed module should only be used in the first switch anyways. They work on timing and 2 load shed modules used together would connect and disconnect loads at the same time (not desirable). I see this type of installation A LOT, especially for homes with interruptible services for A/C or hot water tanks and dual panel services as mentioned here. MUCH cheaper than using the 400A Generac ATS since they get into commercial W style contractors (which are amazing, but not worth it)...