The BT151-500R,127 is a bidirectional thyristor module manufactured by NXP. It is used in applications such as motor control, lighting, and testing and measurement. This module has a nominal blocking voltage of 500V with a load current of 127A. It also has an adjustable trip current from 5 to 20A, a surge withstand current of 300A and an operating temperature range from -40 to 105°C. The center gate provides an internal temperature protection for the thyristor and the integrated snubber network provides excellent arc suppression and sensitive gate triggering.