In the first of a pair of articles on motor fundamentals for HVACR, the author gets into everything from industry standards and service conditions to changing speeds, enclosures, and the often misunderstood service factor. You’ll want to save this one for your team’s reference library.
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.
Retrieving every last bit of performance from the system while stopping short of the surge line is no small feat. Dig into sizing, tower selection, chilled water loads and stability, and condenser water management to leave no efficiency stone unturned. Read more in April issue