The S19 on the right takes two 220V (double hot lead) C-19 plugs, IIRC. Doesnβt matter which order you plug them. 20A circuit.
The S9 on the left just takes regular 110V. 15A circuit is fine.
No problem! Neither unit is probably profitable right now, unless your electricity is super super cheap. But booting them up could still be a useful educational exercise.
Or if you can make use of the waste heat.
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.