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    Class 2 Voltage Drop Calculator (24V)

    Is there an NEC voltage-drop limit for Class 2 circuits?

    No. NEC Article 725 governs Class 2 wiring methods but sets no percentage limit on voltage drop. The real constraint is the powered device's operating-voltage tolerance, which is why the Allowable drop is a field you enter (default 10%) rather than a fixed code value.

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    Use the Class 2 Voltage Drop Calculator (24V) to get an exact answer for your inputs.

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    Related questions

    Estimates and general guidance only. Verify against your local code and AHJ before any installation. Gas, electrical, and refrigerant work is hazardous to untrained users.

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