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| 1. | Create an account if you don't already have one, and log onto the page where you can add components one by one to build up a radial electrical distribution system. The components can be a power source, transformers, bus ducts, cables, motors and generators, or "special" components whereby the user can define his own X and R values for a non-standard device.
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| 2. | Build a one line diagram of distribution system [example].
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| 3. | Pre-assign each basic component within the industrial electrical distribution system a single short circuit MVA factor (SC MVA) based on the impedance it adds to the system, and X/R ratio [more...].
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| 4. | Perform transformation of delta connected components of power distribution system to wye connection before the MVA method implemented in the calculator can be apppied [more...].
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| 5. | Develop a hierarchical tree in terms of database records [more...] Loads not contributing to system's short circuit current (lighting, heating) are assigned a SC MVA value of 0. Unloaded transformers should also be terminated with the SC MVA = 0 node - this allows to calculate short circuits on the unloaded transformer secondary.
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| 6. | Now, as you have all the required data on hand, login and programm in your power distribution system. When finished, click Display button to calculate symmetrical 3 phase bolted fault short circuit MVA from the data compiled in steps 1 to 3. Divide total SC MVA values by 1.73 * kVLL to get short circuit values in kA, or use accompanying SCMVA to KA converter to do it for you:
By performing short circuit MVA analysis for positive, negative and zero sequences, unsymmetrical fault (Phase to ground, Phase to phase) currents can be resolved (see how):
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