The Vishay VS-30TPS12L-M3 is a standard-recovery SCR (silicon-controlled rectifier) in a through-hole TO-247AD package, rated for 1.2 kV off-state voltage and 30 A RMS on-state current. It is designed for line-frequency phase-control applications such as motor drives, power supplies, industrial heating, and battery chargers where a rugged, high-voltage thyristor is needed.
The 1.2 kV off-state voltage (Vdrm/Vrrm) gives headroom for 480 VAC line applications with margin for transients. The 30 A RMS on-state current (It(RMS)) and 20 A average (It(AV)) define the continuous load capability; a heatsink sized for the application's worst-case dissipation is required. The 300 A non-repetitive surge current (Itsm) at 50 Hz covers inrush from motor starts or capacitor charging. Gate trigger current (Igt) is 45 mA max, and gate trigger voltage (Vgt) is 2 V max — these are standard drive levels compatible with common optocoupler or pulse-transformer gate drivers. The 150 mA holding current (Ih) means the SCR will stay latched once triggered as long as the load current stays above that threshold; designs with very light loads should verify commutation.
Package and mounting — TO-247AD
The TO-247AD (TO-247-3 variant) is a widely used through-hole power package with a large metal tab for heatsink attachment. The three-lead form factor is standard for medium-current SCRs, and the isolated mounting hole simplifies thermal management with a mica or silicone pad.