# Transfer switch



## Southeast Power (Jan 18, 2009)

tmessner said:


> Has anyone ever seen a transfer switch with 1 normal and 2 emergency inputs? I have an install with 2 generators on site one for each barn. The owner wants to have a back up power to the backup. In the past I did one with 2 switches by feeding the load from sw #1 to normal on sw 2 and feeding the 2nd genset to the emergency on sw 2, then the load to my panel in the barn. Then repeating this set up for the 2nd barn.


That's exactly how I would do it. Feed both barns with output of SW #2


----------



## Cow (Jan 16, 2008)

What is so important he needs two backups to the utility source? Is he buying crappy generators from an auction that are unreliable?

Is it for a dairy or something else?

We do work for some HUGE (3,000-15,000 cow) dairies that run 24/7 and none of the services have more than one backup generator.


----------



## 3DDesign (Oct 25, 2014)

Usually on a farm, I install transfer switches for portable generators that are powered by a tractor's power take off.


----------



## tmessner (Apr 1, 2013)

This is a boar stud unit where they collect semen. 1 outage where the utility and genset die would pay for this many times over. Last summer we had the regulator go out on the generator during a load control period so it went back to utility, The owner is very concerned that it could happen again. Now he is adding a second barn on the same site so we will have 2 gensets available. the generators are 100 kw 120/240 single phase Blue Star units. They have been very good units with excellent local support. They are also used for poco load mgmt so there is a substantial rate break for the site also. These barns are also air-conditioned so when power fails you have minutes like in 10 or less to get power on or you will have dead hogs from the heat.


----------



## Cow (Jan 16, 2008)

That makes sense. At least they're thinking ahead. I don't care for customers that don't plan and everything is a Chinese fire drill when something breaks down...


----------



## tmessner (Apr 1, 2013)

I just found out that they are getting 2 new gensets with 2 400 amp breakers on each one to feed each barn back up transfer.


----------



## tmessner (Apr 1, 2013)

https://www.electriciantalk.com/attachment.php?attachmentid=133782&stc=1&d=1556073916








Here is a rough sketch of we intend to do.


----------



## Cow (Jan 16, 2008)

I haven't done one like that yet.

That's going to take some time to get that piped and wired!

Grounding and bonding for all that should be fun!!

Do you have it figured out yet how you're going to rework all this gear and still keep them online?

Asco also offers a 3 source ATS.

https://www.ascopower.com/en-us/pro...r-transfer-switches/asco-three-source-system/


----------

