Check the listing for details. SAMGOLD Speed Control DC-51 90V Untested. Condition: Used, Made in United States. Listed at 200.00 USD. The SAMGOLD Speed Control DC-51 90V is a motor control designed for industrial automation and motion control applications. Made by the brand Samgold, this speed control operates at a maximum amperage of 2 amps and a voltage of 110 V. With a power source of AC, this model (DC51) is manufactured in the United States, offering reliable control for your motor-driven systems.