Air Compressors
Heaters & Ventilation
Air Dryers
Variable Frequency Drives
Cooling Systems & Pump Stations
Replacement Parts

Rockwell Equipment
and Supply

216 Fourth St.
Wilmerding, PA 15148
Ph: 412-824-9903
Fax: 412-824-9271

Variable Frequency Drives

Rockwell Equipment sells and services a large selection of engineered products. We offer a variety of variable frequency drives by major manufacturers.

Call us or contact us to request a quote
for specific variable frequency drive product.

Variable frequency drives accomplish part load control by varying electric motor speed, significantly reducing energy waste.


Please feel free to contact us for any of your equipment needs.

Variable frequency drives can be cost effective on a very large range of applications

Variable frequency drives can be installed with manual or automatic bypasses. In the early days of the variable frequency drives, bypasses were more common since variable frequency drives were not as reliable as they are at the present time. The bypasses were installed in the event of a drive failure to ensure the system or process would remain on line. Bypasses are still available but not always installed. The criticality of the application must be considered in each case to determine whether the added cost and security of a bypass is warranted. Harmonic filtering may be necessary in some applications. Variable frequency drives can produce harmonics that can make their way back to the rest of the building and interfere with sensitive electronic equipment and machines. Line reactors can be used on smaller drives of 20 hp and less to dampen and mitigate harmonics. For larger applications, an isolation transformer may be warranted. The isolation transformer can be installed either on the drive or on the piece of equipment to be protected from the harmonics. Because the equipment being protected may be much lower in power, it may be most economical to isolate the piece of equipment from the building supply.

Rockwell Equipment settles into its new home in Wilmerding PA

New HVAC Predictive Maintenance Agreement Reduces Down-time and saves $$$$

Pumps • Air Compressors • Heaters and Ventilation • Lubricants
and more!