General Designed for either bench or rack use, the typical DCR-B power supply provides a highly regulated, precise dc output, adjustable over a wide range. It operates from a nominal 115 Vat (208/220/230 Vat inputs are available as options) and exhibits a rapid response to transients, both load and line. DCR-B series supplies are phase controlled type with SCR’s (Silicon Controlled Rectifiers) or Triacs at the input to the transformer, followed by a passive LC filter. This design allows for a wide range of output voltages, simplicity of design, and offers large amounts of regulated power at relatively high efficiencies compared to linear regulators. Silicon type semiconductors are used extensively in DCR-B circuitry, and contribute significantly, to the units’ wide ambient temperature range characteristic. Low dissipation transistors and diodes are located on a single printed circuit board while high dissipation devices are heat sinked to aluminum brackets and heatsinks. All controls used during normal operation, except the OVP control, are mounted on the front panel. These include a power circuit breaker, FINE and COARSE VOLTAGE adjust potentiometers, and FINE and COARSE CURRENT adjust potentiometers. The system output is taken across a terminal pair at rear terminal strip TB2. A variety of Sorensen power supply application notes are available through your Sorensen Service Representative. These notes detail many hook-up configurations and special usages available to meet most power supply applications. 1.2.2 Automatic Crossover There are two basic operating modes, voltage and current. In the voltage mode, the voltage is held constant while the current varies with the load.