A distance of 1.5 inches from a nonmetallic conduit containing a high-voltage circuit is required when the circuit operates at 100 Hz or less.

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Multiple Choice

A distance of 1.5 inches from a nonmetallic conduit containing a high-voltage circuit is required when the circuit operates at 100 Hz or less.

The main idea is that separating high-voltage conductors in nonmetallic conduit from nearby surfaces is required to prevent arcing and insulation problems. For circuits operating at 100 Hz or less, the code specifies a minimum clearance of 1.5 inches. This low-frequency rule reflects how creepage and dielectric strength behave in typical power-frequency conditions, providing a safe buffer to reduce the chance of arcing or insulation breakdown along surfaces. The frequency threshold matters because different rules can apply at higher frequencies, so the 1.5-inch requirement specifically targets 100 Hz or less. Therefore, the statement is true.

The main idea is that separating high-voltage conductors in nonmetallic conduit from nearby surfaces is required to prevent arcing and insulation problems. For circuits operating at 100 Hz or less, the code specifies a minimum clearance of 1.5 inches. This low-frequency rule reflects how creepage and dielectric strength behave in typical power-frequency conditions, providing a safe buffer to reduce the chance of arcing or insulation breakdown along surfaces. The frequency threshold matters because different rules can apply at higher frequencies, so the 1.5-inch requirement specifically targets 100 Hz or less. Therefore, the statement is true.

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