What is the typical current rating of a standard 40 VA transformer?

To determine the typical current rating of a standard 40 VA transformer, it's important to understand how the volt-amperes (VA) rating relates to voltage and current. The formula used to calculate current is:

Current (in Amps) = VA Rating / Voltage (in Volts)

For a standard transformer used in HVAC applications, the common secondary voltage is typically 24 volts. Using the formula:

Current = 40 VA / 24 V

Calculating this gives:

Current = 1.67 Amps

This calculation explains why 1.67 Amps is the typical current rating for a standard 40 VA transformer. The other options represent current ratings that do not align with this calculation based on the common voltage used for these transformers.