I, too, have a portable hospital on a rolling cart. This is the order I use to shut down:
1) Software Program
2) Spooky Central
3) Spooky Generator(s)
5) Unplug and move!
I'm sure that you, as I, have a power strip on your cart. I just flip the switch to shut off the generators...the laptop runs on battery for the next few seconds. As Trevor suggested, the generators can be unplugged.
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