The below was in the can when your next message came through. There are any number of bad reasons to do it the way you suggest. Relays have their issues, and they tend to fail at the worst possible time under the worst possible conditions. I understand that you are not in downtown Seattle, nor even close to it, so surety and/or redundancy is a big concern. So, if you must use a relay-switch, use one rated for short-cycling and for heavy currents. Also known as a Definite-Purpose Contactor-Switch.

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Of many, many options. This will let you control a 240 VAC line from a 120 VAC line. The activator coil options are many, from 12V to 240V. One bit of advice - DO NOT cheap out on these parts.

Peter Wieck
Melrose Park, PA


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And you do understand what happens to SS (any, actually) relays when they get stuttered power? Such as when a transfer switch kicks in and out? Nothing solid-state likes to be short-cycled unless designed specifically for that. And even mechanical relays wear heavily if short-cycled.

Repeat: Bite the proverbial bullet, run a new heavy-gauge line to the well system, and be done with it. The first time you do not have to go schlepping out to the shop in a howling windstorm you will bless that decision.

Peter Wieck
Melrose Park, PA