CABLE RATINGS

A COOKER IS RATED 2950W IT SAYS IN THE MANUAL TO USE 2.5mm. CAN I USE 1.5mm HEAT RESISTANT CABLE FROM THE COOKER OUTLET TO THE COOKER? AND WHAT SIZE MCB WOULD BE SUITABLE?

Turn your caps lock off mate ,its considered shouting in cyberspace. Then you get told off

If the circuit is supplying ONLY this oven, do as the manual says and use 2.5mm², and fit a 16 amp MCB at the CU.

If there are other appliances on the same circuit or a socket on the cooker switch, which cause a higher rated MCB to be needed, you must fuse down the supply to 13 amps using a 3 pin plug or an FCU, both of which need to be accessible.

Sorry didnt mean to affend anyone. Jus after a bit of help. on the circuit there is a socket and rocker switch together, then it feeds the outlet plate. i thought the socket would be protected by the appliance fuse and the 1.5mm cooker cable by a 16A mcb. am i right to say a 1.5mm cable can carry around 17A?

you could put a 16A mcb on the circuit to protect the oven but that will make trips very likely if you plug anything large (say a fast boil kettle) into the socket while using the oven.

assuming the circuit is wired with 6mm or 10mm cable like a normal cooker circuit a much better bet is to replace the outlet plate with an unswitched FCU (use a good brand like MK and fit the flex first before fitting the thick hard to handle cooker circuit cable then you will be able to protect the circuit with a 32A breaker and therefore use both cooker and socket at full power at once.

as for the flex to the cooker i'd go with the size the manual asks for if only for warranty reasons. (remember if they are specifying heat resistant flex they are probablly doing so for a reason and they may not want too much electrically caused temperature rise added to that)