Where do you plot protection device TCCs?

[Dvhez]

Is around there an open source software, excel sheet, etc to plot at least the standard curves that protection devices often utilize? I use ETAP but sometimes is time consuming to just check a TCC for an specific relay. Also I wanted to ask if it's the same to use an Extremely Inverse curve for two different relays that support this standard curve but they are from different brands. It should be the same right? At most the trip ranges will change.

Thanks!

 

[davidbeach]

If you're dealing with curves based on formulas it should be easy to plot them in excel or Mathcad. If you have to deal with EM relays a program intended for the purpose will be much easier than otherwise. There's a variety of different curve formulas that meet the definition of Extremely Inverse but are not the same and are not interchangeable.