SteveRF
The relay is the best choice to prevent
your pump to restart after a power failure,
but I would else investigate why the motor
will not start.
Is the voltage within specification? Here
in Canada there is a lot of bad
installation with 220Volts motors, building
supplied by 3 phases power have 110/208 ,
single family duelling are supplied by
110/220 Volts split phase, I had 2 enviro
chambers wired for 220 installed in our
building, the electrician assumed that the
lower voltage was OK, but that cause over-
heating and hard starting; a simple low
cost auto-transformer solved our problem.