How you can switch off a 220volt AC equpmend by 24volt DC SUPLY?

Answer 1

First off a word of warning.

230 v is dangerous if badly handled and CAN KILL YOU.

Do not tamper with it whilst the equipment is connected to the mains.

ALWAYS UNPLUG SWITCH OFF AND ISOLATE THE EQUIPMENT BEFORE YOU TOUCH ANYTHING INSIDE.

IF YOU DON'T KNOW WHAT YOU'RE DOING DON'T DO IT! GET SOMEONE IN WHO DOES KNOW!

Assuming you do know how to work safely you will need a DOUBLE POLE relay who's contacts are rated at a minimum 300v (to ensure reliabilityand component life), and which has a coil rated at 24v DC and a switch to control the 24vDC (which must be rated to at least 24v. A higher rating will improve its life and its reliability)

The live and neutral supply should be fed to one side of each set of contacts, whilst the load is taken from the second side of each set.

The coil is controlled by a 24v supply (normally +ve) from a switch being fed to one end of the coil whilst the other end of the coil is returned to the opposite supply pole (normally -ve).

When the switch is "made" the relay coil "pulls in" and both AC poles are switched at the same time.

Turning the switch off de- energises the coil and the relay releases the contacts and thus isolating both AC poles which turns the output side off.