Concerning the Field Representatives: Frequently Asked Questions (FAQs)
Question: When using wire nuts to make joints, is it necessary to twist the conductors together before applying the wire nuts and is it necessary to use insulating tape over the wire nuts? (01 Aug 2004)
Answer: No, see 2002 NEC Section 110.3(B). They are not pre twisted during UL tests and in fact, pre twisting can possibly alter the torque effect of the connector’s design. Also, incidentally pre-twisting wires negates the benefit of these connectors. They do not have to be pre twisted as you would for wrapping with electrical tape. Installation instructions for such connectors are usually found on the smallest unit container and do not state to pre twist the connectors. Also, see UL 486A, section 20.11(d).
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