Abstract—In some electronics devices, such as SCRs and TRIACs, it is necessary that a current flows through its gate in order to control them. To limit this current, a resistor is used in the gate (RG) to provide the TRIAC with the necessary current to control it. This current should not be so large to avoid damaging the device. In practice these resistors are not calculated, they are proposing, this produces insufficient or dangerous currents, which causes in time and money losses. In this work, a designed apparatus solves this problem which consists on a test bank with a PIC18F452 microcontroller and its software allows calculating the RG value automatically in a short time and without damaging the TRIAC. This is possible because the prototype contains a graphic interface and a data acquisition interface which allow the user to introduce the desired current value. The system varies its internal resistance by means of resistors arrangements and it measures the value of the current. If the measured current and the wanted current are different, then the system varies its internal resistance again, this process is repeated until both currents are same; offering to the user the value of the best resistance for the wanted current.

Index Terms—Software, current measurement, microcontroller, TRIAC, SCR.

Miguel Rocha, Leonardo Orozco, Rafael Navarrete, César A. Calva andMa. Del Rosario Osnaya are with the Escuela Superior de Ingeniería Mecánica y Eléctrica, Instituto Politécnico Nacional, México (e-mail:mrocha@ipn.mx).

Cite: M. F. Rocha, L. Orozco, R. Navarrete, C. A. Calva, and M. R. Osnaya, "Software to Determine the Optimal Value of Resistance byCurrent Measurements for TRIACs and SCRs Control," International Journal of Computer and Communication Engineering vol. 1, no. 4, pp. 293-296 , 2012.