Use common sense and a calculator to decide HOW many contactor's you need. I was not saying to put all the lights in a grocery store on the same contactor. A common lighting contactor has two poles. You can light two circuits with it. if you need more, then add more. The protection is at the breaker, not the contactor. Contactors are dirt cheap these days. Material will not be the issue, only labor. If you mount an enclosure right next to the main panel for the contactors it should be a very reasonable proposition to the store owner.
I think it is important to keep store personnel out of panels anyway.
Yeah, mate,
That was what I was thinking when I made the comment above.
I didn't mean one switch/contactor = whole lighting installation.
