you dont say what model of newhome your changing it for? or if the hotplate in made into the work top, . and the newhome is "free standing" on legs" you will have to cut the worktop out to fit in the freestanding newhome,, the wireing will be the same as it is now , same cable rateing,thats comming from the switch on the wall , if it will reach" (make sure) you have all the power off in the home when your takeing the hotplate out, (turn off all the power in your home) open the cooker socket, look at the power lead that is comming from the hotplate. 3 wires go into the bottom of the socket .red /blue/ green or bare copper wire , thats the earth , unscrew them from were they are in the socket, then take the wire out. replace the socket lid . turn the power back on , to put the new one in you wire it the same way as it was , take a photo of it first , and make sure you have the screws very tight , on the new one , (make sure you haveall (the power off) or the sunday roast wont be the only thing cooking......
tom
July 2010