Short Circuit Analysis

What this covers

• Maximum fault levels — three-phase and phase-to-phase currents used to verify equipment withstand and breaking capacity.
• Minimum fault levels — the cases that determine whether protection will reliably pick up a genuine fault.
• Earth fault currents — single phase to earth and double phase to earth, including the effect of the earthing arrangement.
• Equipment rating verification — breaking, making and short-time withstand ratings against calculated duties.
• Motor and generator contribution — the sub-transient contribution from rotating plant that is often underestimated.
• DC component and asymmetry — peak and asymmetrical duties for breaker rating checks.

What you receive

• Short circuit study report with the method and assumptions stated
• Fault level tables at every relevant bus
• Equipment rating verification with any exceedances identified
• Fault data formatted for use in protection setting calculations
• Validated network model for reuse

Standards and references

Calculations follow IEC 60909 or ANSI/IEEE C37.010 depending on the project basis, with equipment duties assessed against IEC 62271 and the relevant IEEE C37 series ratings.