Variable frequency drives (VFDs), also known as variable speed drives (VSDs), are used to modulate the speed of motors in various applications, from hydronic water pumping to VAV fan units to vacuum ...

Bob is a service technician who is well trained and nationally certified. However, he sometimes suffers from the same confusion that all technicians occasionally do - the facts that he gathers may or ...

Keeping a power plant’s surface condenser in proper working order requires paying attention to balance-of-plant systems as well. Failure to monitor and maintain cooling towers and vacuum pumps in ...