SCR also called thyristors, semiconductor thyristors short, SCR T435-600T, it is a small current-controlled high-current switching type semiconductor device, commonly used are ordinary thyristor (also known as one-way SCR) and triac two categories, because of small size, light weight, high efficiency, long life, resistance to vibration, no noise, ease of use. So in a very short period of time to cause the various sectors of domestic, foreign, industrial and agricultural production and great attention it has been widely applied to a variety of production equipment and household appliances. According to trigger pulse voltage and the voltage u gate on the main electrode polarity u combined current characteristic, SCR BT137S-600E, triac trigger can be divided into four types, defined as follows: (1 ) I Trigger: the characteristic curve section Ⅰ quadrant (A positive), relative to the control electrode A positive trigger. (2) I trigger: in Ⅰ quadrant of the characteristic (A positive), SCR, gate opposite A negative trigger. (3) Ⅲ trigger: the characteristic curve section Ⅲ quadrant (A negative), a gate opposite A positive trigger. (4) Ⅲ trigger: the characteristic curve section Ⅲ quadrant (A negative), a gate opposite A negative trigger. SCR, SCR, is provided by Wal-electronic Dongguan City is fertile Electronic Technology Co., Dongguan City is Wo Electronic Technology Co., Ltd (www.dgmydz.com) (www.dgmydz.com) strong, credible, FET and other industries in Dongguan, Guangdong has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead positive fertile electronic and you hand into the brilliant, for a better future!