The S19 on the right takes two 220V (double hot lead) C-19 plugs, IIRC. Doesn’t matter which order you plug them. 20A circuit.
The S9 on the left just takes regular 110V. 15A circuit is fine.
I was also told that the S9 could run on 110V, but when I plugged it in it didn't work. When I plugged it into 220V it ran perfectly. Now I use it as a heater during the winter.
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