What gauge wire from 60 amp ckt breaker feeding 100 amp sub panel in detached garage 70 feet away?

Answer 1

6AWG copper wire should be suitable for this need if being run underground in either conduit or direct burial cable. If you go underground I would recommend using 6AWG wire type "THHN/THHW". If this is to be an overhead installation I would also use 6AWG wire but use aluminum type "XHHW". If running underground in conduit you can use 1" schedule 40 PVC conduit but for ease of pull and future expansion I would run 1.25" conduit.

Answer 2

A 3/0 copper conductor with an insulation factor of 75 or 90 degree C is rated at 200 and 225 amps respectively.A 250 MCM aluminium conductor with an insulation factor of 75 or 90 degrees C is rated for 205 and 230 amps respectively.

Answer 3

Answer for USA, Canada and countries running a 60 Hertz supply service.

This calculation is for a voltage of 240 volts since one was not listed. A #6 copper wire with a insulation factor of 75 or 90 degrees C has an amperage capacity of 65 amps.

To calculate for voltage drop over the distance a #4 copper conductor will limit the voltage drop to 2% or less when supplying 60 amps for 100 feet on a 240 volt system.

Before you do any work yourself,

on electrical circuits, equipment or appliances,

always use a test meter to ensure the circuit is, in fact, de-energized

IF YOU ARE NOT REALLY SURE YOU CAN DO THIS JOB

SAFELY AND COMPETENTLY

REFER THIS WORK TO QUALIFIED PROFESSIONALS.

Answer 4

This is a voltage drop question. The voltage has to be stated before an answer can be given.

Answer 5

For 200 amps the cable size is 0000 or 4/0 which would be OK for a distance up to about 300 ft.

Answer 6

AWG #2 copper