Yes they are essentially a single pole relay, powered by 24VAC. IIRC common from each bay goes to the little connections 24 V hot goes to one of the big terminal. I think all bays have to derive 24V power from the same source. They are commonly used to power procons, or other electric pumps. They have a 20 amp max rating, but if the motor shorts it will take it out. I have fused the output in the past, I prefer to use them to power contactors.