The ampacity of conductors that connect a capacitor to motor terminals or to motor circuit conductors shall not be less than what percent of the capacitor's rated current?

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Multiple Choice

The ampacity of conductors that connect a capacitor to motor terminals or to motor circuit conductors shall not be less than what percent of the capacitor's rated current?

Explanation:
When a capacitor is connected to motor terminals, the wire carrying the capacitor current must handle more than the steady running current of the motor. Capacitors can draw a high charging surge and create reactive current that can peak well above the rated running current, especially during startup or when capacitor values are larger. To protect the conductor from overheating and to provide a safe margin for these peaks, the ampacity is specified as at least 1.35 times the capacitor’s rated current. This 135% allowance accounts for possible variations in capacitor values, voltage changes, and real-world worst‑case conditions, giving a practical safety buffer. Other percentages either don’t provide enough margin for these inrush and reactive effects (125% might be used in other motor conductor contexts, 110% is inadequate) or are more conservative than necessary (150%). Hence, the conductors should be sized for 135% of the capacitor current.

When a capacitor is connected to motor terminals, the wire carrying the capacitor current must handle more than the steady running current of the motor. Capacitors can draw a high charging surge and create reactive current that can peak well above the rated running current, especially during startup or when capacitor values are larger. To protect the conductor from overheating and to provide a safe margin for these peaks, the ampacity is specified as at least 1.35 times the capacitor’s rated current. This 135% allowance accounts for possible variations in capacitor values, voltage changes, and real-world worst‑case conditions, giving a practical safety buffer. Other percentages either don’t provide enough margin for these inrush and reactive effects (125% might be used in other motor conductor contexts, 110% is inadequate) or are more conservative than necessary (150%). Hence, the conductors should be sized for 135% of the capacitor current.

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