Schneider Electric (Viconics) R851B-8 8 Stage AC/DC Step Controller

The Schneider Electric (Viconics) R851B-8 is an 8-stage step controller designed for precise control of multi-stage applications, commonly seen in HVAC equipment. It works by controlling the mains' alternating current (AC) power and transforming it into direct current (DC). The controller then uses a technique known as "chopping," in which it quickly flips this DC voltage on and off to produce a variable voltage output that is fed back to the AC side. There are various advantages to this exact control over the electricity supplied to HVAC equipment. It improves efficiency and lowers operating costs by adapting energy consumption to actual demand.Additionally, by allowing fans and motors to run at lower speeds, it lessens the noise they produce.