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Generac does have a 2 wire function. Never used it . Let me look at a kohler RDT for you. They have start stop terminals and they are the brain as far as detecting utility failure.
 

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Discussion Starter #23
Just to confirm it has 2 coils and the plungers move in a straight line like Generac?

On the outside, it looks just like the one Cummins sells which is a GE/Zenith?

I just like dealing with Cummins better, maybe I will have them send me a picture.
 

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To the question of the contractor.

Trust me when I tell you, get a mechanically latched contactor. An electrically held contactor will hum, and eventually the HO will hear it and complain. That's why lighting contractors are often latched. The thing is, it means a different kind of switch, because you have a latch and unlatch coil. But they make toggle switches for that, they are 3 position, momentary up and down for on and off, spring return to center.

Good source? Asco actually. They make them up to 200A,
http://www.emersonnetworkpower.com/en-US/Products/PowerSwitchingandControls/IndustrialControls/LightingControls/Pages/default.aspx
 
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That is basically what I would like to do but there is no provision for that in the genset controller, to start and stop on command. You can convert the genset to start and stop on a 2 wire contact closure input but once you do that your utility monitoring goes away and you can't use the Generac cheaptransfer switch any more.

Maybe I could do the same thing with the Asco style switch but I don't have one in front of me to play with and not knowing how they are wired ahead of time, it is too risky to go and buy one and then see if it works for me or not.

Fortunately I have a job on Monday where there is a Thomson transfer switch of the same style so we will see how that one works internally.

Thanks for the ideas.
Trying to stay cheap on highly specialized setup may be part of the difficulty?
 

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Trying to stay cheap on highly specialized setup may be part of the difficulty?
I wouldn't say cheap has anything to do with it other then this person just doesn't want to waste gas if no ones home so wants the ability to disengage load and turn off . This can normally be dome on generator by switching breaker and pressing off. It prevents the brushes from getting damaged. It is the proper procedure for shutomg down to check oil too.
 

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I wouldn't say cheap has anything to do with it other then this person just doesn't want to waste gas if no ones home so wants the ability to disengage load and turn off . This can normally be dome on generator by switching breaker and pressing off. It prevents the brushes from getting damaged. It is the proper procedure for shutomg down to check oil too.
so forget about using cheap generac switch?
 

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Sounds like a terribly stupid idea, and you're re-inventing the wheel. It's been said already, but kill the engine, cutting the load won't do much as the machine will still be idling. Also, using a toggle switch isn't very bright either. If he forgets to close the switch for whatever reason and leaves, the generator will start, but the contactor won't be closed and he won't get any power. I wouldn't do this, but if I did, I would use something with no voltage protection and a small NC contactor.
 

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To the question of the contractor.

Trust me when I tell you, get a mechanically latched contactor. An electrically held contactor will hum, and eventually the HO will hear it and complain. That's why lighting contractors are often latched. The thing is, it means a different kind of switch, because you have a latch and unlatch coil. But they make toggle switches for that, they are 3 position, momentary up and down for on and off, spring return to center.

Good source? Asco actually. They make them up to 200A,
http://www.emersonnetworkpower.com/en-US/Products/PowerSwitchingandControls/IndustrialControls/LightingControls/Pages/default.aspx

Good point, add that to my list in the post I made yesterday. :thumbup:
 

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Discussion Starter #35
Does the ASCO 920 need to have momentary open/close (coil) voltage, or can you leave the operating voltage on the terminal indefinitely?
 

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Good point, add that to my list in the post I made yesterday.
Generators generally like to be run unloaded for several minutes to allow for engine cool down rather than being shutdown immediately. This is genrally a function of the transfer switch, so keep that in mind
 
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