SHORT CIRCUIT CURRENTS CALCULATION FOR RING MAIN UNIT

[arnsam]

Can anyone help me with the accurate calculations on shortcircuit currents for RING MAIN UNIT. I have 8 Nos 800kVA 11/0.415kVA transformers which are supposed to be installed in ring circuit.

I would like to get a spreadsheet or something similar together for the design of shortcircuit currents so as I can get appropriate circuit breakers and isolators.

Some help from you experts would be very much appreciated.

Thanks in advance.
Eng. Arnold J. Samugabo

 

[davidbeach]

I'd model it in a software system like SKM, Etap, Easypower, Aspen, etc. rather than trying to keep track of everything by hand.

 

[matwong]

We haven't done any calculation like that before but it may not be a concern since most of the RMU easily rated higher than 20kA@1s.