Question: Under what conditions is a torque wrench required when terminating a wire to a lug?
See the answer below.
Answer: Whenever the manufacturer provides a specific tightening torque value.
Explanation: Section 110.14 (D) was added to the 2017 NEC and requires the use of a calibrated torque tool whenever the manufacturer provides a specific torque value. The manufacturer may also provide an alternative method of achieving the proper torque.
Lupacchino is a senior design engineer with Gaylor Electric, Inc. in Noblesville, Ind. and serves as an alternate on NEC Code-Making Panel No. 3. He is currently licensed in more than 80 jurisdictions. He can be reached at [email protected].