Article 240

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Overcurrent Protection 240.20 Ungrounded Conductors Part II. Location The word “approved” was replaced with “identified for the purpose.” The result… nails, screws, or wire are no longer permitted to be used for circuit breaker handle ties. Handle ties must be identified for the purpose, which means designed by the manufacturer to perform this function. (B) Circuit Breaker as Overcurrent Device. Circuit breakers must open all ungrounded conductors of the circuit, unless otherwise permitted in 240.20(B)(1), (B)(2), and (B)(3). (1) Multiwire Branch Circuit. Except where limited by 210.4(B), individual single-pole breakers are permitted on each ungrounded conductor of a multiwire branch circuit that supplies line-to-neutral loads. Figure 240-1 (2) Single-Phase, Line-to-Line Loads. Individual single-pole circuit breakers with handle ties identified for the purpose are permitted on each ungrounded conductor of a branch circuit that supplies single-phase, line-to-line loads. Figure 240-2 (3) Three-Phase, Line-to-Line Loads. Individual single-pole breakers with handle ties identified for the purpose are permitted on each ungrounded conductor of a branch circuit that serves three-phase, line-to-line loads. Figure 240-3 Author’s Comment: Handle ties made from nails, screws, wires, or other nonconforming methods are not permitted. Figure 240-4

Figure 240-1 (Click on image to enlarge) Figure 240-2 (Click on image to enlarge) Figure 240-3 (Click on image to enlarge) Figure 240-4 (Click on image to enlarge)