#8 would be fine if you ground each panel separately to the ground rod
No. Usually when you get to that size panels the grounds are stranded.
The recommended ground wire size according to the NEC Ground Wire Size Chart is based on the amperage of the circuit.
The size of the ground wire for a circuit is typically based on the size of the circuit breaker protecting that circuit. For a 200 amp circuit breaker, the recommended ground wire size is 4/0 AWG (American Wire Gauge) copper wire. This wire size helps ensure that the ground wire can safely carry any fault currents that may occur in the electrical system.
Yes, there are ground wire gauges. The approiate size ground wire must be matched to the size service you are installing. For instance a 200 amp serivce must be grounded with a # 4 bare copper ground wire.
A Ground or Earth wire is wire used to connect the frames and outer casings of appliances and power supply panels to the Earth.For more information see the answer to the Related Question shown below.
The recommended ground wire size for a 100 amp sub panel installation is typically 8 copper wire.
The recommended size for a 50 amp ground wire in electrical installations is typically 10 AWG (American Wire Gauge).
The recommended size of the ground wire for a 60 amp electrical circuit is typically 10 AWG (American Wire Gauge).
The ground wire in a two or three conductor #12 cable is a #14 bare ground wire.
The ground wire size chart provides guidance on the appropriate size of ground wires to use in electrical installations to ensure safety and compliance with electrical codes.
A #14 wire will do fine for grounding a 20 amp device. That is the size of the ground wire in a 2 conductor # 12 wire building cable.
1/0 copper