TCC Based on Formulas

In some digital relays, formulas are used to generate the TCC. EasyPower includes the following formulas in the library:

    IEC Formula

    Multilin ANSI Formula

    Basler / Siemens Formula

    Schweitzer Formula.

    ABB PCD2000 Formula

    RXIDG Formula

    Locked Rotor Constant I^2t Formula (Westinghouse IQ-1000 formula)

To enter TCC data for formulas select the applicable formula name from the Model box in Section 2 of Relay Info as shown in the figure below.

Figure 1: Model Box for Relays

The figure below is an example of the Basler formula. The formula used for calculating the TCC appears below the model name. The values used in the formula are entered in the spreadsheet and edit fields.

Figure 2: Basler Formula

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