Well-known protocols include Profibus DP, DeviceNet and Modbus Plus. Installation and Commissioning Ask your supplier to see a VFD instruction manual. Text keypads are much easier to program than numeric ones. Experiment with the keypad to determine how simple or complex the programming is. Ask about programming options to aid commissioning, such as PC software and application-specific macros.
Service Ask about the warranty and service policy-sometimes an extended warranty is available.
A 24-hour technical assistance number is important as is a local manufacturer s representative. Conclusion VFDs offer many advantages over the traditional methods of pressure control in a distribution network. They provide precise pressure control, reduce water leakage, increase pump life and result in significant energy savings. A careful selection of a VFD supplier should be made for trouble-free operation of the system and to enable you to reap the benefits of the VFD technology to the maximum extent.