Single Phase generator on a 3 phase service

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T74

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Has anyone has a problem with installing a single phase generator with ATS as part of a back up for a 3 phase system?

All the loads are single phase, mostly refrigerators and freezers.
 
If there are any MWBCs connected to the three phase panel downstream of the transfer switch you will not be able to simply parallel all three lines to the generator output.
If the generator output is 120/240 single phase and your service is 208Y/120 it gets more complicated, since it will be harder to balance loads to the two sides of the generator.
 
GoldDigger said:
If there are any MWBCs connected to the three phase panel downstream of the transfer switch you will not be able to simply parallel all three lines to the generator output.
If the generator output is 120/240 single phase and your service is 208Y/120 it gets more complicated, since it will be harder to balance loads to the two sides of the generator.
Click to expand...

The main panel is 3 phase but all the branch circuits are fed from 100 amp 1 phase panels. My plan was to make one of the sub panels into a generator panel with an ATS between the main panel and sub panel.
 
T74 said:
The main panel is 3 phase but all the branch circuits are fed from 100 amp 1 phase panels. My plan was to make one of the sub panels into a generator panel with an ATS between the main panel and sub panel.
Click to expand...
Really single phase, as in only one ungrounded bus? Or "single phase" as in two out of three phases brought to two ungrounded buses?
The latter should fit in fine with a 120/240 generator.
 
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Two potential problems:

1) Any line-line loads must be able to function at both 208 and 240V.
2) No load must depend on the phasing between the two line-neutral sides of the panel. (This is _very_ unlikely to be a problem)

-Jon
 
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