Conductors smaller than 1/0 AWG can be connected in parallel to supply control power provided which conditions are met?

• A. They are all contained within the same raceway or cable
• B. Each parallel conductor has an ampacity sufficient to carry the entire load
• C. The overcurrent protection is such that the ampacity of each individual conductor will not be exceeded if one or more of the parallel conductors becomes disconnected
• D. All of these

Answer: (D)

When you parallel conductors smaller than 1/0 AWG for control power, three safety and performance criteria must be met to keep the circuit safe and reliable. First, all the parallel conductors must be inside the same raceway or cable so they operate in the same thermal environment and share heat similarly. Second, every parallel conductor must have enough ampacity to carry the entire load by itself, so if some parallel paths are disconnected, the remaining ones can still handle the load without overheating. Third, the overcurrent protection must be chosen so that the current in any individual conductor will not be exceeded if one or more parallel conductors are removed, ensuring the remaining conductors aren’t overloaded. When all of these conditions are satisfied, paralleling conductors for control power is permitted.