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Once the short-circuit levels are known, rated values and settings are determined for all protective devices of the power network. The protection devices include protective relays, trip units and fuses. Short-circuit and normal load currents allow determining the protection devices size, type and their characteristic time-current. Similarly, the settings are shown in time-current characteristics so that equipment is protected against overload and short circuits.
The settings are made according to industry accepted standards such as CSA, ANSI / IEEE, IEC and others. The protection coordination study optimizes equipment protection, selectivity and this ensures backup protection in the event of failure of the main protection. Our experts can characterize special equipment to protect – such as transformers, motors, capacitor banks, lines, cables, reclosers, etc. – CYMTCC, SKM and ETAP software are used for modeling typical equipment and for the protection coordination of time-current curves. Specific settings for transformers, generators, motors, among others – e.g. the differential protection – are also part of the protection study.