1 question, what is the formula of the ampers to the size of the wire? the total amper of my workshop is 158 amps. the total loads...i just want to know the size of the cable wire will i use from the transformer to the breaker to be safe.

 

According to NEC table 310.16, the smallest conductor you could use is 1/0. However you might want to go bigger than that, so that in the future you could plug in a microwave or vacuum cleaner and not have to worry.

 

What kind of shop are you running? What kind of equipment? How did you come up with 158 amps?

 

I have a new fabrication shop, with 3 welding machine and 2 grinding machine. a welding machine has 47 amps x 3 = 141 amps plus the grinding machine .. almost 150 amps the total laods...what is the size of the cable will i use from my work shop's breaker to the transformer?

 

Shouldn´t the power company be taking care of the line between their transformer and the panel with the meter and breaker?