I have bought a Wifi controlled device to control a 3KW, 240V water heater (immersion heater) wirelessly but despite being advertised as 15A, it actually has a 13A relay which has "push fit" contacts. I'm not sure I trust it to run for several hours at its maximum rating. I want to replace the relay with a 25 or 30 amp rated relay which will therefore be operating well below it's rated load.
However the original isolator switch to the immersion heater is dual pole. Should I therefore use a dual pole relay behind the isolator switch, or is this not necessary? Is there any advantage of using dual pole in this scenario? Given it's just a resistive load, I'm not sure if there's any particular merit of using a dual-pole relay in this situation?
Best Answer
OK, I've been informed the your supply voltage is 240v to ground. Your isolation switch that is a double pole. They either switched the neutral or left the second pole vacant. There is no reason to use a double pole relay, a single pole will be just fine.
Just make sure your Wifi control device can deliver the necessary coil voltage/current for your new relay.