Siemens Building Technologies Inc.: VFD Enclosure
November 19, 2004
The NEMA 3R enclosure package for the line of SED2 variable frequency drives (VFDs) is equipped with a main input fused disconnect and optional two- or three contactor bypass and line reactor. The enclosures allow outdoor mounting of VFDs near the controlled mechanical equipment and permit short motor lead lengths for optimum performance, the company states. The enclosure package protects the VFD and bypass components from rain, snow, and ice, and the cabinet is provided with a shield that protects the unit from heating effects of indirect sunlight, the manufacturer says. A filtered inlet, fan-controlled exhaust and thermostatically controlled heater are supplied to ensure that required enclosure ambient conditions are maintained between 32 degrees and 104 degrees F (0 degrees to 40 degrees C). A high-temperature option is available for locations that can reach up to 122 degrees (50 degrees C).
Siemens Building Technologies Inc., Buffalo Grove, IL; www.sbt.siemens.com/hvp.