15mm approx.
A wire size of at least 250 MCM (thousands of circular mils) is typically recommended for a current of 312 amps. Using wire size calculators or consulting with an electrician is advisable for specific installations to ensure the correct wire gauge is used for safety and efficiency.
The appropriate wire size for a circuit requiring 60 amps is typically 6-gauge wire.
The wire rating for a # 12 wire is 20 amps. If you are going to continuously load the circuit you need to de-rate the wire by 80%. This brings the current down to 20 x .8 = 16 amps. The wire rating of a # 10 wire is 30 amps. 30 x .8 = 24 amps.
You would need to use a wire size that is rated for at least 40 amps to be safe and to meet the requirements of the air conditioner. A common wire size for this application would be 8 AWG copper wire, which is rated for 40 amps.
The appropriate wire size for a circuit that requires 30 amps of current is typically 10-gauge wire.
AWG 10.
The recommended wire size for a circuit carrying 35 amps of current is typically 8 AWG (American Wire Gauge).
The recommended wire size for a circuit carrying 80 amps of current is typically 4 AWG (American Wire Gauge).
15 amps.
4/0 (4 ought) in copper will handle 250 amps. The voltage drop at 175 ft. is about 2.14 volts which should be okay.
# 4 copper wire short distance.
300 Amps if used for service entrance conductors. Table 310.15