HDC DC Load Solid State Contactors Crydom HDC Solid State Contactors (SSCs) are designed for control of high power DC loads such as brakes, clutches, coils, electromagnets, heaters, lamps, motors, and solenoids, where long life and fast switching are required. These Crydom solid-state relays are designed for applications in which traditional mechanical contactors or relays do not provide the required life, performance, or service levels. The HDC SSCs offer DC solid-state power control due to an advanced high-speed DC switching circuit for on/off or PWM control (up to 1KHz). These devices utilize optically isolated low dissipation FET outputs rated at either 120A or 160A at 48VDC, 72VDC, or 150VDC operating voltage.