Wiring a freestanding cooker

[clownshat]

I have recently done up my kitchen and have opted to change my integrated electric hob and oven for a free standing electric cooker. The old appliances seemed to use two wires, which were fed off the same 'cooker switch' on the wall above the hob.
Do I need to use both of these cables to wire up my cooker, or can I just use one of these and terminate the other with some connector block and insulating tape.
I have tried the afore mentioned method but am getting no power to the cooker. I have metered the wires and am getting no voltage. I am using 30A fuses in the consumer unit and have checked that they are working ok.
I cannot see where the wires come out from the wall as they are behind the cupboards, Is there a possibility that the guys refurbidshing my kitchen have done some damage to the wiring when removing the old hob and oven? (BTW the cupboards/layout have not been changed, only the doors and worktops have been replaced)

 

[conny]

If you are not getting any voltage at either cable end then it seems you have damaged cables, a blown fuse or disconnected wires somewhere between the cooker and the CU.
Remove the fuse and check again, if it is ok then with the power off remove the live wire(s) from the fuse holder in the CU. Remove the neutral(s) from the neutral bar and twist together with its corresponding live wire. Go back to the cooker end and set your meter to 'continuity' now test across the live and neutral of each cable. If it reads zero you do not have a circuit and will have to investigate further. If one of the cables shows a circuit then twist the ends together and go back to the CU. Now untwist these cables and test for continuity at this end. The pair that show a circuit are the ones you should use to connect the cooker to. Isolate the other cable and either remove it completely or insulate it from all other cables etc at both ends. Connect the live to the fuse terminal and the neutral to the neutral bar. Replace the fuse and check for voltage at the cooker end, if you have voltage remove the fuse and connect up to cooker. Refit fuse and test cooker is working. Be careful as cooker will need at least 6mm2 T&E, preferably 10mm 2 and make sure your earth is connected at both ends!
If cooker has a timer/clock make sure it is set or cooker may not function until it is.
(willing to accept corrections by someone more upto date or better method )