Final answer:
The minimum conductor size on the secondary of the control transformer is 24 AWG.
Step-by-step explanation:
The minimum conductor size on the secondary of the control transformer can be determined using the information given. Since the transformer is a step-down transformer, the current on the secondary side is higher than the current on the primary side.
We need to find the maximum current on the secondary side, which is equal to the maximum input current divided by the turns ratio. The turns ratio can be calculated by dividing the primary voltage by the secondary voltage.
In this case, the turns ratio is 480/24 = 20.
The maximum current on the secondary side is then 5A / 20 = 0.25A.
To determine the minimum conductor size, we can use the 60 C column of the 28.1 table.
Looking up the current rating for a 0.25A current in the 60 C column, we find that the minimum conductor size is 24 AWG.