Arc Fault in Assisted Living Unit

[Duncan8943]

I am doing an assisted living unit which is classified as R-4. If I run everything in MC cable from the panelboard, do I need to protect this circuit with an arc fault breaker? The code allows for an arc fault receptacle at the first box if MC cable is ran from the panelboard. One would think that if the entire circuit is MC cable then AFCI would not be necessary.

 

[david]

One would think that if the entire circuit is MC cable then AFCI would not be necessary.

Does the arc fault protect just the branch circuit? Does it protect cords plug into rec?

 

[eprice]

I am doing an assisted living unit which is classified as R-4. If I run everything in MC cable from the panelboard, do I need to protect this circuit with an arc fault breaker? The code allows for an arc fault receptacle at the first box if MC cable is ran from the panelboard. One would think that if the entire circuit is MC cable then AFCI would not be necessary.

Maybe I don't understand your question correctly. You could use an arc fault receptacle at the first box rather than the breaker because that is allowed by code. If you are asking can you omit AFCI protection entirely because the entire circuit is in MC cable, the answer is no. The code doesn't allow that. One likely place for an arc to occur would be at a splice in a box. The use of MC cable doesn't reduce the chance for an arc to occur at at splice in a box.