I have seen conflicting reports about whether or not the secondary of a single phase transformer feeding a lighting panel board must have secondary over current protection. I can't find it in the most recent NEC. I realize that if the primary overcurrent is sized at 125%, the secondary protection isn't usually necessary. But, is a lighting panelboard an exception that requires this secondary protection?
Single phase transformer with lighting panelboard
- Thread starter crawfj
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- Logan, Utah
The secondary windings of the transformer would not need individual protection if you follow the overcurrent protection requirements of 450.3(B) and the primary overcurrent protective device is rated at not over 125%.
You are required though, to have secondary conductor protection in accordance with 240.21(C) and 408.36(D) (2005) or 408.36(B) (2008).
Chris
You are required though, to have secondary conductor protection in accordance with 240.21(C) and 408.36(D) (2005) or 408.36(B) (2008).
Chris
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