Adding a 2nd transfer or interlock

Automatic standby generator installation questions. Wiring, placement, code requirements, etc.
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xpert66
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Morning..I currently have an 8kw standby with a 10 circuit ATS. I was thinking of adding a power inlet box to the house so I can run my portable generator at times to give my standby unit a rest and avoid running several extensions cords throughout the house. Can this be done?
grsthegreat
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i dont see why not, but you will need a different manual interlock on the panel. one that locks out the main breaker when feeding from generator. since its a manually configured device, it would be up to you to make sure 8kw unit is turned off before engaging the other source. you cant simply tie the portable generator into the existing generator transfer switch feed.
xpert66
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grsthegreat wrote:
Sat Aug 08, 2020 5:27 pm
i dont see why not, but you will need a different manual interlock on the panel. one that locks out the main breaker when feeding from generator. since its a manually configured device, it would be up to you to make sure 8kw unit is turned off before engaging the other source. you cant simply tie the portable generator into the existing generator transfer switch feed.
That's what i was thinking. So could I use my existing Generac transfer switch that has the circuits I need powered? I am guessing I need to wire the inlet box to the main but do I need another breaker added to the main?
Chris
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There would be a lot to making this correct and safe I think. You'd need to manually isolate the standby generator feed from the optional portable feed with some type of interlock and breaker setup. I would consult with a local electrical inspector before taking this one on. You want to make sure that if someone were working on the auto standby (if it was down) that the neutral feed from the portable isn't passing through the auto standby gen, or someone could be killed if taking something on the electrical side apart.
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xpert66
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Chris wrote:
Mon Aug 10, 2020 12:08 pm
There would be a lot to making this correct and safe I think. You'd need to manually isolate the standby generator feed from the optional portable feed with some type of interlock and breaker setup. I would consult with a local electrical inspector before taking this one on. You want to make sure that if someone were working on the auto standby (if it was down) that the neutral feed from the portable isn't passing through the auto standby gen, or someone could be killed if taking something on the electrical side apart.
Thanks will do further research!
johhen
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I know it varies by inspector/county/city, but was curious if you ever finished this project? I had a similar thought, for redundancy / fuel efficiency during long outages when we consume only a few hundred watts.
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