Short Circuit, ARC Flash and Coordination Studies

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Protection Coordination Studies And On Site Adjustments

The protective device coordination study is performed to develop optimal settings for selectable circuit breakers, protective relays, and fuse sizes. These settings are selected to isolate faults and/or overloads at the closest point to the abnormal condition in the system. The objective of this study is to provide protection to system components and personnel by removing the fault condition as quickly as possible.

The overcurrent device time-current coordination analysis determines the suggested settings and where appropriate, the ampere ratings and types for the electrical power system protective devices to achieve the desired system protection and electrical service continuity goals.

ITD offers the following services for protection coordination:

  • A reference one-line diagram identifying components.
  • Proper NEC, ANSI, and IEEE protection/selectivity parameters.
  • Appropriate current scales.
  • Graph reference voltage.

Arc Flash And Risk Analisys In Electrical Equipment

We offer to perform this analysis in accordance with the calculations defined by the NFPA-70E and supply the warning labels with the information obtained as result of the study such as equipment's flash protection boundary, its incident energy level, and the required personal protective equipment (PPE).

Arc Flash is the result of a rapid release of energy due to an arcing fault between a phase bus bar and another phase bus bar, neutral or a ground. During an arc fault the air is the conductor. Arc faults are generally limited to systems where the bus voltage is in excess of 120 volts. Lower voltage levels normally will not sustain an arc. An arc fault is similar to the arc obtained during electric welding and the fault has to be manually started by something creating the path of conduction or a failure such as a breakdown in insulation.