The only twist lock , code wise, that i'm aware of is in 680, otherwise it's a matter of location, vibration, # of prongs.... [Linked Image]

The 'circuit that broke the panel's back' is much more interesting, seems like i'm always there myself, looking for non-coincidental loads,dead circuit runs, wondering if they can run it for 179 min's at a time,maybe a fancy T-switch,,,,etc.

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