Q. Must receptacles be installed so they can be removed without interrupting the power to any downstream receptacles?
A. Continuity of the grounded neutral conductor of a multiwire branch circuit must not be interrupted by the removal of a wiring device. Therefore, the grounded neutral conductors must be spliced together and a pigtail must be provided for the wiring device.
Caution: If the continuity of the grounded neutral conductor of a multiwire circuit is interrupted, the resultant over- or undervoltage could cause a fire and/or destruction of electrical equipment.
The opening of the ungrounded conductors or the grounded neutral conductor of a 2-wire circuit during the replacement of a device doesn’t cause a safety hazard, so pigtailing these conductors isn’t required [110.14(B)].
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