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Short Circuit Analysis

What are Short Circuit Currents?

Short-Circuit Currents are currents that introduce large amounts of destructive energy in the forms of heat and magnetic force into a power system.

The reliability and safety of electric power distribution systems depend on accurate and thorough knowledge of short-circuit fault currents that can be present, and on the ability of protective devices to satisfactorily interrupt these currents. Knowledge of the computational methods of power system analysis is essential to engineers responsible for planning, design, operation, and troubleshooting of distribution systems.

Risks Associated With Short Circuit Currents

The building/facility may not be properly protected against short-circuit currents. These currents can damage or deteriorate equipment. Improperly protected short-circuit currents can injure or kill maintenance personnel. Recently, new initiatives have been taken to require facilities to properly identify these dangerous points within the power distribution of the facility.

Why Do I Need a Short Circuit Analysis?

Short Circuit analysis is required to ensure that existing and new equipment ratings are adequate to withstand the available short circuit energy available at each point in the electrical system. A Short Circuit Analysis will help to ensure that personnel and equipment are protected by establishing proper interrupting ratings of protective devices (circuit breaker and fuses). If an electrical fault exceeds the interrupting rating of the protective device, the consequences can be devastating.  It can be a serious threat to human life and is capable of causing injury, extensive equipment damage, and costly downtime.

On large systems, short circuit analysis is required to determine both the switchgear ratings and the relay settings.  No substation equipment can be installed without knowledge of the complete short circuit values for the entire power distribution system.  The short circuit calculations must be maintained and periodically updated to protect the equipment and the lives. It is not safe to assume that new equipment is properly rated.

Benefits of a Short Circuit Analysis

Performing a Short Circuit Study provides the following benefits:

  • Reduces the risk a facility could face and help avoid catastrophic losses.
  • Increases the safety and reliability of the power system and related equipment.
  • Evaluates the application of protective devices and equipment.
  • Identifies problem areas in the system.
  • Identifies recommended solutions to existing problems.

Contact Us for more information on how a Short Circuit Analysis can benefit you.