Application Guide

63-70625
Benefits Summary
— Improved control.
— Reduced plant wear.
— Quieter operation at low load.
— Reduced complaints.
— Lower operating costs.
— Typical payback period is less than 2 years.
VFD MARKET
Energy Costs
The forces for industrial automation, requirements for ever increasing efficiencies from plant and machinery, together with
demands for higher performance at a lower cost, continue to fuel rapid VFD market growth.
VFD Costs
Modern manufacturing techniques, using new technology Micro-Controllers, Digital Signal Processors, Application Specific
Integrated Circuits (ASIC) and other highly integrated devices, have substantially reduced the VFD component count. Typically,
VFD component counts have dropped from several thousand for early designs, to around 500 for modern machines. The result
of this is not only smaller physical size, but also substantial reductions in overall cost and increase in reliability (see Fig. 1).
Other factors which have a lowering effect on market prices
— Wide VFD acceptance within industry and commerce.
— Larger volumes, produce benefits of scale: greater purchasing power by manufacturers and suppliers, larger investment in
automated manufacturing processes.
Size
Functions
Reliability
Cost
Fig. 1. Trends in the VFD Marketplace.
What’s New
Another benefit of using advanced technologies in manufacturing and high performance chip sets, has been the availability to
produce controllers with many more features.
In the early VFD days, more than 20 years ago, the machine had simple functionality, produced by the use of basic analogue
technology. These machines had limited functions, providing the basics of speed control and soft start and stop.
Modern control of a general purpose VFD is digital, with what seems to be an ever growing list of functions:
— Multiple programmable digital inputs.
— Multiple programmable digital outputs.
— Multiple programmable analogue inputs.
— Multiple programmable analogue outputs.
— Closed loop high accuracy speed control.
— An array of motor protection functions.
— Simple plc. type functions.
— Simple but effective torque control.
— Communication bus.