The wires from the meter terminate at a double pole switch (double pole switches break both the live and neutral) inside the consumer unit. On the other side of the switch, the neutral is joined to a connector block which accommodates all the neutral, blue (old cable colour = black) wires from your circuits. The live, brown (old cable colour = red) goes to a bar, which sits behind one end of all the fuses. The link from here to the terminal of each circuit is protected by a fuse mounted between the two. Another connector block accommodates all the earth (green and yellow) wires from your circuits and connects them back to the main earth terminal. *NEMA 3R rating is specified for outdoor use, primarily to provide a degree of protection against falling rain or sleet; and to be undamaged by the formation of ice on the enclosure.