QK010R5

Thyristors - TRIACs

A TRIAC, or Triode for Alternating Current, is a type of thyristor which enables a single device to control current flowing in both directions. The QK010R5 is a zero-crossing type TRIAC, which is triggered when the current flow reaches zero. It features a moderate voltage rating (800V), and a relatively low current rating (10A).

Application Field

The QK010R5 is designed to be used in applications such as AC motor control, temperature and humidity control, static switching devices, lighting, power control in heating and lightning systems, etc. The device can also be used to construct AC digital signal interfaces, and in small electrical tools. Its zero-crossing feature is especially useful for controlling high power electric motors.

Working Principle

TRIACs require a bi-directional neutral current to be applied to their main terminals (MT1 and MT2). The gate voltage applied to their gate terminal (G) turns the TRIAC on and off. When the gate voltage is below a certain value (<1.6V voltage drops), the TRIAC\'s conduction channel is blocked. When the gate voltage is above this value, the conduction channel between MT1 and MT2 turns on. This conduction channel then turns off when the main current reaches zero.

The QK010R5 has a special feature which allows the gate current to be reduced by a factor of 10. Thus, it is suitable for controlling large loads with relatively small gate voltage. As the QK010R5 is zero-crossing enabled, it helps to avoid electrical hazards, increases the lifetime of the device and provides higher level of accuracy.