Crydom dp series 4 channel dc reversing solid state contactors crydom dp4rsa60d20 a 20a 4 channel dc reversing solid state contactor with a 45 to 15v dc control voltage a 1 to 48v dc operating voltage and a soft start02s ramp up operating mode the contactor has a h bridge configuration and is designed for chassis mounting via suitable themal management suitable for use in lighting control magnetic starters vacuum contactor applications crydom dp4rsa60d20 solid state relay h bridge 48