Arc flash question

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ablogix

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Hello, my company is trying to follow NFPA70e without any training or pay for an analysis. The question i have in the table 130.7(c)(9), 600v class MCC it says working on control circuits 120v or below is cat 0. Is that with the 480 off or is it permissible as long as you dont touch the 480 circuit.

Thanks
 
ablogix said:
Hello, my company is trying to follow NFPA70e without any training or pay for an analysis. The question i have in the table 130.7(c)(9), 600v class MCC it says working on control circuits 120v or below is cat 0. Is that with the 480 off or is it permissible as long as you dont touch the 480 circuit.

Thanks
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The control circuits need to be in a sepreate compartment or if in the same the 480 would need to be off. But the real question here is how are they justifing doing this work energized?

You need to do part of the analysis to follow the 70E, in order to use the tables you need to know the available fault current and the clearing time of the protective device and be withing the limits listed in the notes of the tables or the 70E requires you do an analysis. Also you can't follow the 70E without training, it is required. I suggest you learn the requirements (The FAQ's in the safety area of this forum will get you started) and present them to your company, if they don't change thier mind, consider a new employer. THe phrase knowing enough to be dangerous applies here.
 
yes i totally agree. The boss was told by a electrical supplier that if he used the Ferraz Shawmut A6D fuse he didn't have to do an expensive analysis. Anybody hiring?
 
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