What is the role of the SCR? One role is controlled thyristor rectifier, which is the most basic and most important SCR role. We know it can be done only diode rectifier circuit thyristor rectifier function BTA216, not controllable, but do change once the diode SCR, they constitute a controlled rectifier circuit. In a basic single-phase half-wave controlled rectifier circuit, when a sinusoidal AC voltage in the positive half cycle, the control electrode is applied only when the trigger pulse, SCR was only triggered thyristor conduction, the load will have voltage output, so you can trigger pulse arrival time on the pole by changing the control to further regulate the average value of the output voltage to the load, to the role of controlled rectifier. SCR polarity determination multimeter R × 1K range measuring positive and negative resistance SCR poles, positive and negative resistance to elect two very big difference, which that measure the resistance measured in smaller In the black pen connects to a control electrode (G), red table pen connects to the cathode (K), the rest of a pole on the anode (A). By determining the polarity of thyristor also be qualitatively determined that the SCR is good or bad. If you test positive and negative resistance in any small difference between the poles of both SCR BTA316, its resistance are large SCR BTA208, instructions G, open-circuit fault exists between K; if there are positive and negative poles between resistance is very small, and close to zero, the SCR internal short circuit fault exists between the poles. SCR T435-600T | are fertile Electronics (certified) | SCR Dongguan City is provided by Wal-Electronic Technology Co., Ltd. Dongguan City is Wal-Electronic Technology Co., Ltd. (www.dgmydz.com) (www.dgmydz.com) is Dongguan, FET leader, over the years, the company is implementing the scientific management, innovation and development, the principle of honesty and trustworthiness, the maximum limits to meet customer needs. Wal-electronics leader in the positive with the staff warmly welcome all inquiries negotiations to create a positive future Wal-electron better.