Negative sequence current calculations
Negative sequence current calculations
(OP)
Hi
Does anyone know where to find a simple spreadsheet that can calculate negative sequence current from a set of 3phase currents?
I am preparing a test of a Siprotec 7UM62 with a Omicron CMC256 and Siemens doesent specify how to test the function.
If I e.g. injects 1.2pu on two phases and 0.8pu on the 3rd I want to calculate I2. With that value I can find the expected tripping time on the curves or by the formulas.
Best Regards
Preben Jakobsen
Does anyone know where to find a simple spreadsheet that can calculate negative sequence current from a set of 3phase currents?
I am preparing a test of a Siprotec 7UM62 with a Omicron CMC256 and Siemens doesent specify how to test the function.
If I e.g. injects 1.2pu on two phases and 0.8pu on the 3rd I want to calculate I2. With that value I can find the expected tripping time on the curves or by the formulas.
Best Regards
Preben Jakobsen





RE: Negative sequence current calculations
RE: Negative sequence current calculations
RE: Negative sequence current calculations
lmgtfy...
h
=====================================
(2B)+(2B)' ?
RE: Negative sequence current calculations
*cough* Rotate phase 2 (W, S, V or whatever you call it where you are) by 240 degrees, rotate phase 3 (B, T, W or whatever you call it where you are) by 120 degrees, add the vectors and divide by 3.
*cough*
RE: Negative sequence current calculations
RE: Negative sequence current calculations
My relay has an instant trip function but also a time dependant function which i would like to test at different points.
I have found a page www.relaytech.com/symcomp_calculator.htm which can do the calculations, but a spreadsheet for quick calculations on site would be nice.
Best Regards
Preben Jakobsen
RE: Negative sequence current calculations
RE: Negative sequence current calculations
Use the help function to look up how to access it.
RE: Negative sequence current calculations
RE: Negative sequence current calculations
Very powerful.. Just enter the magnitude and degrees you are looking for, click convert and it will tell you to input into the test set.
FYI if everything says #NAME and it doesn't work, see the instructions on the first tab to enable the "Analysis ToolPak"
RE: Negative sequence current calculations