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#204272 - 11/25/11 11:03 AM Automating Manual Gen Transfer Swtich...
johnmixdecn Offline
New Member

Registered: 11/25/11
Posts: 1
Loc: NY
Hi all. I have a setup with a diesel genset. This genset feeds a 3 phase panel (120/120/120). This panel has 4 double breakers, each feed a single phase panel, each of which has a manual transfer switch that switchs the panel between line power and the 3 phase gen panel. This has worked well for years.

What im looking to do is to automate this. Installing 3 auto transfer switchs is beyond my budget.

What im thinking is I will write a program that runs on a dedicated PC (on battery backup of course) that will watch the incoming power, and when we lose power, or a even lose a single will start and warm up the genset. Then it will wait a few minutes then flip each transfer switch over. I have writen a similar program for a smaller application that was in a communications shed in the woods. It worked great.

This is where my question comes in. Would it violate code in any way to have an electric actuator push/pull the handle of the transfer switchs from "Line" to "Gen"? I cant see how it would since this is external from any electrics and is doing this same thing as a human fliping the switch.


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#204273 - 11/25/11 12:20 PM Re: Automating Manual Gen Transfer Swtich... [Re: johnmixdecn]
gfretwell Offline


Registered: 07/20/04
Posts: 9023
Loc: Estero,Fl,usa
When you change a manual transfer switch to automatic (any way you do it) you do bring in the requirement that the generator now must be capable of maintaining the entire connected load.
Does your program do load management?
Other than that you might bump into 110.3(B) about using equipment the way the manufacturer's instructions specify.
Greg Fretwell


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