I am not familiar with the Indian Electrical Code but in North America a #14 copper conductor with an insulation factor of 90 degrees C is rated at 15 amps. The CEC and NEC do not rate wires smaller than #14 for home or commercial construction.
For a 30 amp breaker, you will need a wire that is at least 10 gauge in size.
For a 50 amp breaker, you would typically need a 6-gauge wire.
For a 50 amp breaker, you will need a wire that is at least 6 gauge in size to safely handle the electrical load.
You will need to use #8 wire.
8 AWG is typical.
2AWG.
For a 100-amp service, you will typically need a wire size of 2/0 or 3/0 copper or 4/0 aluminum. It is recommended to consult with a licensed electrician to determine the exact wire size needed for your specific installation.
The recommended wire size for a 20 amp breaker is typically 12-gauge wire.
The recommended wire size for a 30 amp circuit is typically 10 gauge wire.
The recommended wire size for a 60 amp circuit is typically 6-gauge wire.
The appropriate wire size for a 20 amp circuit is typically 12-gauge wire.
The appropriate wire size for a 25 amp breaker is typically 10 gauge wire.