the power supply.
To comply with the 1000 volt-ampere limitation of
725.41(A), the maximum output (VA max) of power sources other than transformers shall be limited to 2500
volt-amperes, and the product of the maximum current
(/max) and maximum voltage (V max) shall not exceed
10,000 volt-amperes. These ratings shall be determined
with any overcurrent-protective device bypassed.

VAmax is the maximum volt-ampere output after one minute of operation regardless of load and with overcurrent protection bypassed, if used. Current- limiting impedance shall not be bypassed when determining VAmax.

Anax is me maximum output current under any nonca- pacitive load, including short circuit, and with overcurrent protection bypassed, if used. Current- limiting impedance should not be bypassed when determining / max. Where a current-limiting impedance, listed for the purpose or as part of a listed product, is used in combination with a stored energy source, for example, storage battery, to limit the output current,
7max limits apply after 5 seconds.
Vmax is the maximum output voltage regardless of load with rated input applied.

(B) Class 1 Remote-Control and Signaling Circuits. These circuits shall not exceed 600 volts. The power output of the source shall not be required to be limited.

725.43 Class 1 Circuit Overcurrent Protection. Overcur- rent protection for conductors 14 AWG and larger shall be provided in accordance with the conductor ampacity, without applying the derating factors of

310.15 to the ampacity calculation. Overcurrent protection shall not exceed 7 amperes for 18 AWG conductors and 10 amperes for 16 AWG.

Exception: Where other articles of this Code permit or require other overcurrent protection.

FPN: For example, see 430.72 for motors, 610.53 for cranes and hoists, and 517.74(B) and 660.9 for X-ray equipment.

725.45 Class 1 Circuit Overcurrent Device Location.

Overcurrent devices shall be located as specified in
725.45(A), (B), (C), (D), or (E).

(A) Point of Supply. Overcurrent devices shall be located at the point where the conductor to be protected receives its supply.

(B) Feeder Taps. Class 1 circuit conductors shall be per- mitted to be tapped, without overcurrent protection at the tap, where the overcurrent device protecting the circuit conductor is sized to protect the tap conductor.

(C) Branch-Circuit Taps. Class 1 circuit conductors 14

AWG and larger that are tapped from the load side of
the overcurrent protective device(s) of a controlled
light and power circuit shall require only short-circuit and
ground-fault protection and shall be permitted to be
protected by the branch-circuit overcurrent protective
device(s) where the rating of the protective device(s) is
not more than 300 percent of the ampacity of the Class 1
circuit conductor.

(D) Primary Side of Transformer. Class 1 circuit conduc tors supplied by the secondary of a single-phase trans former having only a 2-wire (single-voltage) secondary shall be permitted to be protected by overcurrent protection provided on the primary side of the transformer, provided this protection is in accordance with 450.3 and does not exceed the value determined by multiplying the secondary conductor ampacity by the secondary-to-primary trans former voltage ratio.