ATS Control wiring

Automatic standby generator installation questions. Wiring, placement, code requirements, etc.
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NorthernABTech
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Hello all. I just purchased a Honeywell Generac RXSW100A3CULH. This is my first time wiring in an ATS and I'm not familiar with what exactly "T1" to "23 Transfer Control" terminations do.

Here's my best guesses. I believe is T1 would be an optional +12VDC supply to charge your battery. N1&N2 say "Utility sense" so I'm guessing a sensing line from each 120VAC line runs here to allow the ATS to sense utility power. "0 Ground" would be ground from your generator. "194 +12vdc" connection sounds like the generator starer wire. Finally, "23 transfer control" I've read on this forum is a ground connection too. What is this grounding/bonded to?

Please let me know if I'm right on my guesses and feel free to elaborate on any that I'm wrong about.

Thanks in advance!
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grsthegreat
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T1 supplies 120 VAC for powering controller and battery charge circuits.

N1&N2 are current sensing circuits. These are reading utility 240 VAC power to tell controller when utility power is present, and to,provide power for winter kit options.

0 is ground wire used mainly for load shedding by the onboard SACM unit.

194 is powered 12VDC continuously

Wire 23 is used by controller to take circuit to ground to cause transfer mechanism to move during power outage and removed from ground to move transfer mechanism back to normal when power is restored.
NorthernABTech
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Thank you very much for answering all my questions.
NorthernABTech
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grsthegreat wrote:
Fri Aug 13, 2021 12:25 pm
T1 supplies 120 VAC for powering controller and battery charge circuits.

N1&N2 are current sensing circuits. These are reading utility 240 VAC power to tell controller when utility power is present, and to,provide power for winter kit options.

0 is ground wire used mainly for load shedding by the onboard SACM unit.

194 is powered 12VDC continuously

Wire 23 is used by controller to take circuit to ground to cause transfer mechanism to move during power outage and removed from ground to move transfer mechanism back to normal when power is restored.
Couple questions:

-T1 is 120vac in? so a guy should take power from utility power side? Or how does it get a constant 120vac power to power the controller? If this is the case there is a rectifier in the controller to output 12vdc?

-194 termination power out?

-so does termination 23 basically a negative for 194? Or does it have 12vdc supply going through it and then just grounds out when line power is lost?

-what is the negative termination connection for 194 and 23 if they output 12vdc?

Thanks!
grsthegreat
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T1 gets its power from the T1 terminal of the transfer mechanism. The T1 terminal is where the leg that feed the house power lands. That way it has 120v either under utility power or under generator power.

Circuit 194 is positive 12VDC all the time, provided by generator battery. It gets the negative side by landing wire 23 to ground within the controller. This completes the circuit when utility is lost and generator has warmed up.
NorthernABTech
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Just to hopefully clear things up. I dont have a generac controller or generator package. I have a different brand generator and a custom built control panel that I made with how a fellow electrician described how he believe units work. I see now that T1, N1&N2 have constant power associated with the main power terminations.

Basically how I have my control panel setup is that it requires 12vdc constantly. When the line power drops a 2nd 12vdc circuit completes and energises relays.

Sounds like from what you describe I will also need a 120vac to 12vdc rectifier, and a battery charger.

0 should be connected to the ground connection in my ATS?

So 23 only completes the 194 to 23 circuit once the generator is started? My understanding was that the ATS will transfer power once it senses proper voltage on E1/E2.

I have spoken to a master electrician, and multiple other journeyman electricians and none of us are able to get any of this information from Generac. They all state it is high risk. Do they only give this information out if you take some sort of Generac specific course?!?
grsthegreat
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well, i dont know how any of our info pertains to a non generac generator or custom made switch. On the generac transfer switch the generator decides when to transfer power by taking wire 23 to ground thus completing 12vdc circuit to transfer switch. the generator has to be producing 240 VAC to cause the actual transfer mechanism to activate though.

when power return and N1 & N2 are sensing 240 VAC, the generator waits about 30 seconds to see if power remains steady, then it removes 23 from ground, allowing the 240V utility power to throw transfer mechanism back to utility.

on Generac switches, 0 wire is a ground wire that is used by the old style (before nexus,evolution controllers) battery chargers and on newer switches is only required if there is a load shed module (SACM) installed and in use in the switch.
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