Generally, when we think about BAS, it is in the context of large commercial buildings, those well over 25,000 sq ft. According to the latest government data though (from the 2012 Commercial Building Energy Consumption Survey), 88% of all commercial buildings are 25,000 sq ft or less.
Reactors for AC drives are available as either AC reactors or DC reactors (DC link chokes). Both serve the same main purpose: to smooth the current flow to the AC drive, and reduce damaging harmonics produced on the power line.
The VARIOspeed® VFD is designed specifically for pressure control applications. As the flow and head conditions change in the pumping system, the VARIOspeed® VFD is able to automatically control the pump speed and maintain a constant discharge pressure.