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Torque basics for techs: inch-pounds vs foot-pounds, click wrench use and care, and terminal torque (NEC 110.14(D))

1 ft-lb = 12 in-lb: divide inch-pounds by 12 to get foot-pounds, multiply to go back. Small screws and electrical terminals are usually specified in in-lb, so read the unit before setting the wrench. Since the 2017 NEC, section 110.14(D) says that where equipment or instructions give a tightening torque, a calibrated torque tool must be used (unless the maker gives another method). The code panel's reason: testing showed installers got the torque wrong in up to 75% of connections by feel. Loose terminals overheat; over-tight ones crack blocks and strip threads.

Cross-checked ~10 min easyBrands: All

Before you start

  • Power off and verify dead (live-dead-live) before torquing any electrical terminal.
  • Never torque a gas fitting or valve; that is licensed gas-tech work.

Diagnostic steps

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Torque basics for techs: inch-pounds vs foot-pounds, click wrench use and care, and terminal torque (NEC 110.14(D)) · OnCall Tech