On Sun, 18 Aug 2019 22:03:16 +0100, Adrian Brentnall
wrote:

HI Folks
As the subject says - can't seem to find a contact that operates off
12volts on the coil, and is rated to switch 40+ amps @ 240v a/c.

Does such a thing exist - or do I have to use a a slave relay from the
12v to switch a 240v coil?

Yes as others have already said, at a price.

Many industrial contactors in more recent years have been modular and you could
mix and match coil voltages into a common contact base, easily adding auxiliary
contacts and indicators.

For the coil 24v 48v 110v and 240v are common across a wide range of
manufacturers, 12v remains extremely rare.

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