CONSTANT TORQUE VFDS Requirements: • Complete Table I1 of the “Process Systems Incentive Catalog Supplemental Data Sheet” for this measure. • Only constant torque VFDs for existing building applications are eligible for incentives below. Use of constant torque VFDs for new construction may qualify for custom incentives. • VFDs must be installed on constant torque equipment (e.g., conveyors, positive displacement pumps, extruders, mixers, crusher/shredders). VFDs installed on a centrifugal or axial flow pump or fan, i.e., a variable torque load should use the Variable Torque VFD offer on page 20. If neither offer is applicable, the project may qualify for a custom incentive. • The system using the VFD must operate a minimum of 2,000 hours annually. • If VFD is going on a motor greater than 500 HP, please fill out table I2 to provide the estimated load profile for the piece of equipment. Please also provide the motor nameplate efficiency (motor specification or nameplate photo) for large motor over 500 HP. • VFD speed can be automatically controlled by differential pressure, flow, temperature or other variable signal, or be manually controlled. • Air compressors are not eligible for this offer. Instead, use the Variable Speed Drive Air Compressors on page 11. • For VSD vacuum pumps ≤ 30 HP, see Compressed Air and Vacuum section of this catalog. VSD vacuum pumps > 30 HP may qualify for a custom incentive. EQUIPMENT UPGRADES AND RETROFITS Measure Description Code Incentive Unit Constant Torque VFD PS3280* $35 HP
PRO TIP Constant torque loads are defined as the torque requirement being constant at all speeds. Equipment such as cranes, hoists, conveyors, or mixers are constant torque. Constant torque power varies linearly with speed.
PRO TIP The power requirement of the fan or pump varies as the third power of the speed ratio. Therefore small decreases in speed by using a VFD will result in large savings.
21
Powered by FlippingBook