Can a General Duty or Heavy Duty safety switch be back fed(or Reverse fed) attaching the incoming Line wires to the Load side of the switch)?
Heavy Duty Safety Switches
Back(or Reverse) Feeding
No, Back feeding of a General Duty or Heavy Duty safety switch is not recommended. This application may be in violation of the National Electrical Code (NEC) Article 240.40. Regardless of the NEC interpretation, backfeeding of a Heavy Duty safety switch would not be considered a safe practice, considering the following:
1. In a fusible device, the fuses and Blades would be "hot", regardless of operating handle position.
2. In a non-fusible device, the blades would be "hot", regardless of operating handle position.
3. In a receptacle switch application, the pins of the plug would be accessible and "hot", regardless of the operating handle position.
The wiring diagrams provided on the safety switches are marked with LINE and LOAD markings. Wiring other than the direction shown on the wiring diagram would be considered a violation of the NEC Article 110.3(B).