Feb 26, 2022 · 40-amp 240-volt circuit: 40 amps x 240 volts = 9,600 watts. 50-amp 240-volt circuit: 50 amps x 240 volts = 12,000 watts. 60-amp 240-volt circuit: 60 amps x 240 volts = 14,400 watts. The simple A x V = W formula can be restated in a number of ways, such as W ÷ V = A, or W ÷ A = V. The Spruce / Michela Buttignol.