Electronically Controlled Bypass (ECB) packages provide improved protection and operation through a bypass 24-vdc switch mode power supply. The company says the package integrates the most desired bypass system control features, including automatic bypass, common start/stop in drive or bypass modes, and advanced firefighter’s override, which works in coordination with the drive and bypass for improved protection. Contactor operation is unaffected in harsh conditions; drive operation can be maintained at reduced output with input as low as 70 percent of nominal voltage, or even with one input phase missing. According to the manufacturer, this improves operation when compared with standard transformer power supplies, or power supplies that only operate off of two legs of input power. Packages are available in two- or three-contactor configurations, from 1/2-350 hp at 460 and 600 vac, or 1/2-60 hp at 208 and 230 vac.
Danfoss Drives, 8800 W. Bradley Rd., Milwaukee, WI 53224; 800-621-8806; 414-355-6117 (fax); email@example.com; www.namc.danfoss.com