In a tunnel wiring, the type of switches used is

4

415 V

TPIC switch works as a main switch for 3-phase AC line. It is used for controlling a 3-phase power with 4-wire system. A fuse and a neutral link is connected in series with each line. The switch switches ON/OFF all the three phase lines simultaneously.
The voltage rating of TPIC switch is 415 Volts.

16 A to 200 A

extend the length of the wire without jointing