To answer this question the voltage value and whether the system is three phase or single phase needs to be given.
#2 aluminum for 100 amp
A #1 copper wire with an insulation rating of 90 degrees C is rated at 140 amps.
20Sqmm
A #1 aluminum wire with a insulation factor of 90 degrees C is rated at 105 amps. Three #1 wires can be installed into an 1 1/2" conduit.
1/0 copper thhn covering. 3/0 aluminum again thhn covering
#2 aluminum for 100 amp
3/0 or250 aluminum
A #1 copper wire with an insulation rating of 90 degrees C is rated at 140 amps.
A 3/0 aluminum conductor will limit the voltage drop to3% or less when supplying 125 amps for 175 feet on a 220 volt system. If the 125 amp load is a sub distribution panel that is not going to be fully loaded to 125 amps then using the exact connected load, which might be smaller than 125 amps will effect the wire sizing. The grounding conductor for that size distribution panel is #6 bare copper.
#6 3 conducter
20Sqmm
For a 100 Amp breaker panel it would be 2 AWG. For 150 Amps it would require 2/0 (2 ought) aluminum wire.
A #1 aluminum wire with a insulation factor of 90 degrees C is rated at 105 amps. Three #1 wires can be installed into an 1 1/2" conduit.
1/0 copper thhn covering. 3/0 aluminum again thhn covering
This type of question usually means you aren't ready to do this yourself. Study some electrical material and the National Electrical Code and work this answer out for yourself. If I were to give you an answer, you might attempt to do something you shouldn't be doing, and that may cost someone a shock, a home fire, or their life.
A piece of aluminium (or aluminum) can come in different sizes.
yes. because you didn't add anything to it or take anything away from it. so it's just a different size.