While they're rated at 200 W, the Series 1721 dc-dc converters are designed for critical dc power applications that require the back-up/redundant features often only provided in larger dc power systems. They include two independent converters housed in a single 1.75-in. high rack-mount enclosure, with integral output OR-ing diodes for each converter. These dual-converter units can be operated from a single dc source, yet provisions also were made for dual input feeds. Users then can provide truly redundant power to radio transceivers, telecommunications equipment, supervisory control systems, and other critical electronic loads. Nine standard models are available with different combinations of dc input voltage (24, 48, or 130 V dc) and dc output voltage (13, 24, or 48 V dc). Other combinations are available by special request. Key specs include a well-regulated dc output; mutual electrical isolation between input, output, and chassis; 30°C to 60°C operating ambient temperature range; and auxiliary Form C contacts for remote monitoring of converter status. The single-piece price is $594. Units are typically available from stock.