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Can a neutral be shared when using two 1p CAFI, AFI, GFI, DF, or EPD breakers? (shared neutral)

Issue:
For 1p QO, QOB and HOM breakers, can the neutral for two 120V 1p circuits be shared between two 1p CAFI, AFI, GFI, DF, or EPD breakers?

Product Line:
Circuit Breakers

Environment:
Applies to 1p QO, QOB, and HOM breakers with suffix CAFI, AFI, GFI, DF or EPD

Cause:
Two 120V circuits are sharing the neutral wire.

Resolution:
For 120V circuits that are fed by 1p CAFI, AFI, GFI, DF or EPD breakers, the neutral should NOT be shared between two circuits. Doing so will cause one or both breakers to nuisance trip. The circuits should be wired in such a way that each 120V circuit has its own neutral.
NOTE: If existing wiring already uses shared neutrals between two 120V circuits, and re-wiring is not an option, consider using one 2p breaker in place of the two 1p breakers (if local electrical code allows). The following 2p breakers types are available:
2p CAFI (use on 120/240V system; not for use on 208Y/120V system)
2p GFI (use on 120/240V as well as 208Y/120V systems)
2p EPD (use on 120/240V as well as 208Y/120V systems)
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