ceiling lights?

i want to fit a spot light, i took the old light down and there is one cable with 3 wires,red,black,green/yellow, plus a seperate cable with 1 wire, red. the new spot light has block with 4 connections marked N,E,& L the forth is not marked how should the wires be connocted -i think the black goes to the N ,the green/yellow to the E, but not sure about the reds does the separate wire(red) go to the L and the red wire in the cable with the black and green/yellow go to the unmarked block.what will happen if this is wrong and i switch on.