Home switches and sockets can not tell the red and yellow three lines so how to get it ah
It is best not to open the hole from the bottom of the bridge, if necessary, do the mouth to do sealing treatment to prevent the bridge from the mouth of the water poured into the power distribution device.
Recommend you look at this: wire gauge wire diameter table
Power cable and control cable in a bridge laying, too close will be affected, especially in the automation of the instrument, the speed accuracy is not too high for the inverter is not big, will not burn potentiometer
