NEC Arc Flash Reduction

[timm333]

I have a question about NEC 240.87(B)(3). We are re-using old circuit breakers which don’t have arc flash reduction maintenance switch (AMS), because these breakers were built in the year 2009 and at that time there was no requirement of 240.87.

Does NEC 240.87 apply to these breakers, if yes then should we use external arc flash reduction maintenance switch (AMS) for these breakers? Thanks

 

[don_resqcapt19]

If you are making a new installation, you have to comply with the currently adopted code.

 

[timm333]

Ok thanks. If the breaker does not have arc flash reduction maintenance switch (AMS) and we want to use the same breaker. Then should we use a different trip unit on the same breaker, or should we install an external AMS switch on the breaker, which of these two options would be better?

 

[don_resqcapt19]

Ok thanks. If the breaker does not have arc flash reduction maintenance switch (AMS) and we want to use the same breaker. Then should we use a different trip unit on the same breaker, or should we install an external AMS switch on the breaker, which of these two options would be better?

Any of the methods listed in the code are fine...with all of the supply issues, it will probably come down to which one you can obtain in time to complete your project.