The T243-500-28 from Proton-Electrotex JSC is a Silicon Controlled Rectifier with Breakover Voltage 2800 V, Breakover Current 10.5 to 12.5 kA, Gate Trigger Voltage 1.50 to 3.00 V, Gate Trigger Current 150 to 400 mA, Temperature Operating Range -60 to 125 Degree C. Tags: Disc. More details for T243-500-28 can be seen below.