Modify ATS to Manual transfer only?

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tortuga

tortuga

Code Historian
Location
Oregon
Occupation
Electrical Design
Greetings all customer has a ATS for a 14kw generator on a 200A single phase service, but as things change they no longer need the 'automatic' part and are adding loads. I was asked to disable the automatic transfer function of an ATS and just make a manual transfer circuit, like and 'transfer' trigger switch next to the ATS?
I know you can get all fancy with a load management system or split the loads out of the panel to a critical loads panel.
I am just wondering if anyone has done this?
Thanks
 
In my situation, my generator can be heard by the neighbor when she is in bed, so we don't want it to run then. Also, we spend half the time at our other house on the coast, and don't want it to just keep running when we are not there. So I put a simple toggle switch in the line from the ATS that starts the generator.
 
Should be as simple as a SPDT switch. Most of them use micro switches to cut power to the transfer magnets once the switchover is complete, so you just need to energize them manually and they will de-energize themselves automatically.
 
What brand?

On Generac, you could put a switch inline with Wire 23, but the genny would still start automatically on utility sense loss.

Easiest would be to set the gen to off, and when they want to start it, turn it to manual, or auto, if they want it to automatically transfer over when utility is restored.
 
Seven-Delta-FortyOne said:
What brand?

On Generac, you could put a switch inline with Wire 23, but the genny would still start automatically on utility sense loss.

Easiest would be to set the gen to off, and when they want to start it, turn it to manual, or auto, if they want it to automatically transfer over when utility is restored.
Click to expand...
Easy enough it is a Generac
Thanks 41!
 
Since the ATS sends the signal to start the gen (when gen control is in auto position) a simple way is to install a toggle switch in one of the start wires (of the pair of wires) to disable the gen from starting on a PF. This would not allow the gen to start and hence prevent transfer of the ATS. Closing the TS would resume normal automatic operation. This is common logic on all ATS/ gen systems since an ATS will not transfer to Emer without gen power to the ATS.
 
Seven-Delta-FortyOne said:
What brand?

On Generac, you could put a switch inline with Wire 23, but the genny would still start automatically on utility sense loss.

Easiest would be to set the gen to off, and when they want to start it, turn it to manual, or auto, if they want it to automatically transfer over when utility is restored.
Click to expand...
I think what you meant to say is "if they want it to automatically transfer over (to gen) when utility is LOST." Please see my post #6.
 
ATSman said:
Since the ATS sends the signal to start the gen (when gen control is in auto position) a simple way is to install a toggle switch in one of the start wires (of the pair of wires) to disable the gen from starting on a PF. This would not allow the gen to start and hence prevent transfer of the ATS. Closing the TS would resume normal automatic operation. This is common logic on all ATS/ gen systems since an ATS will not transfer to Emer without gen power to the ATS.
Click to expand...
Generac doesn’t work like other generators, the ats does not send a signal to start like everybody else. The sense circuit is at the generator, which in turn sends a signal for the switch to transfer. Breaking the power wire starts the generator, which the generator sends 12 vdc to a relay to transfer.
 
ATSman said:
I think what you meant to say is "if they want it to automatically transfer over (to gen) when utility is LOST." Please see my post #6.
Click to expand...

I make little sense speaking, and even less when I type out what’s in my head. 😳

I was saying, easiest way is set it to off. When power is out and they want gen power, push “manual”, or, if they want the genny to shut off when utility comes back on, set it to “auto”.

They’ll have to come back out at some point to set it back to “off” so it doesnt auto start.
 
hillbilly1 said:
Generac doesn’t work like other generators, the ats does not send a signal to start like everybody else. The sense circuit is at the generator, which in turn sends a signal for the switch to transfer. Breaking the power wire starts the generator, which the generator sends 12 vdc to a relay to transfer.
Click to expand...
Ok, tks hillbilly for that bit of knowledge! Sounds like Generac operates as an exception rather than the rule. But I still think it would work by having the toggle switch interrupt the power wire preventing gen start and ATS transfer. I don't do residential so never work on Generac systems. My world is commercial/ industrial with ATSs by ASCO, Kohler, Zenith (ABB), Onan (Cummins), Russelectric (Siemens), Westinghouse (Eaton), etc.
 
ATSman said:
Ok, tks hillbilly for that bit of knowledge! Sounds like Generac operates as an exception rather than the rule. But I still think it would work by having the toggle switch interrupt the power wire preventing gen start and ATS transfer. I don't do residential so never work on Generac systems. My world is commercial/ industrial with ATSs by ASCO, Kohler, Zenith (ABB), Onan (Cummins), Russelectric (Siemens), Westinghouse (Eaton), etc.
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Yeah, your post works for everybody except Generac residential, they are built as cheap as possible, with homeowner installation in mind.
 
Generac uses two utility sense wires, so if you switch one off, the generator will never transfer to utility.

I had that on a service call the other day, one of the fuses was blown on one of the utility sense wires.

Code said “utility sense lost” and it wouldnt Transfer to utility.
 
Seven-Delta-FortyOne said:
Generac uses two utility sense wires, so if you switch one off, the generator will never transfer to utility.

I had that on a service call the other day, one of the fuses was blown on one of the utility sense wires.

Code said “utility sense lost” and it wouldnt Transfer to utility.
Click to expand...
Who in their right mind would design a system that puts a fuse in the V sensing circuit!?!? o_O That's why in these parts we use the
term "Junk-er-Rac" in place of Generac ;)
 
They are made for homeowners and residential electricians that are not fluent in controls. I’ve installed several generators for local electrical contractors, whose customers went with better quality generators. Remote annunciation panels and hardwired load sheds stump them.
 
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