Aiee. Vacuum motor @3A = 15A startup at least and inductive spike like
nothing else. You probably want to use a lot of protection like MOVs and a
heavy snubber and a triac rated 10A or so. Even better use a relay rated
10A for inductive load and a snubber on it. If the motor turns very easily
the snubber may not let it spin to a stop after a run. You have to check
...

Peter

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