AIC and Arc Flash study

[Davebones]

Looks like management is going to get a Arc Flash Study done in our plant . As this facility has been here since the early 80's would it not be prudent to also verify the ( AIC ) ratings of the breakers in the panel at the same time.I understand we have the series rated method in the plant . I know a lot of work has been done with no engineer input over the years .Does a Arc Flash study look at that at the same time ??????

 

[zog]

If it is done right they will look at the AIC's to ensure they are adequate, but I have seen some very scary arc flash studies being done by self proclaimed experts.

 

[skeshesh]

The engineer that I personally know and consider an expert pretty much always does. Usually it's a power system study that's conducted in its entirety. The only case that I can think of where he accepted to do an arc flash study on its own was when a short circuit study done very recently (a year or two prior) was provided to him.

 

[Pierre C Belarge]

If it is done right they will look at the AIC's to ensure they are adequate, but I have seen some very scary arc flash studies being done by self proclaimed experts.

Maybe the brightness of the arc gets in flash's eyes keeping him from performing a good study....

 

[ron]

Short circuit calculations are required in order to do an arc flash study.
In the world of competitive bidding (if that is your case), the calculated fault current at each bus might not be compared to the AIC or withstand rating of your equipment.
It is an additional step, and if it is not in the scope, it is not necessarily done.

 

[Davebones]

Keep the information coming . I want to be able to give management the information of why all of this should be done at the same time . I do appreciate all of the information everyone has given me on this and many other questions . Again thank you for the help .

 

[zog]

Just like most things, you need to do your homework on who will be doing your study, get references, ask questions, etc... Low bid is usually not the best idea.

Ask what software they are using, SKM, easy power, Etap, etc.. There are lowballers out there using outdated free arc flash calulators, saw 2 of those last week.

Really it comes down to your spec, what your company requires to be on the analysis. I can send you some samples if you like so you know what to ask for.