Vacuum Pumps The installation of a Variable Velocity Drive (VSD), sometimes called a adjustable frequency drive, usually saves between 50 and 65% in electrical power costs with the same or better regulation of vacuum. The number of energy savings could be from 30 to 80 percent. They can be adapted to blower or in some cases rotary vane type vacuum pumps. They function by changing the speed of the vacuum pump based on the reading from a pressure sensor that’s installed on the vacuum line near the receiver jar. The VSD is basically a dedicated pc with many adjustments so it could be possible to boost vacuum regulation over the typical pneumatic vacuum regulator that just has a 
vacuum level adjustment. A VSD for a vacuum pump is usually economical for a dairy that milks a complete of 8 hours or more per day. Typically a VSD will not be a cost-effective option for little dairies because of less milking time and therefore shorter vacuum pump operate times but there are Energy-Conserving Vacuum Pump several other choices to save energy costs.
