Patent US 5,651,264

A flexible process controller for coordinating the operations of various equipment is disclosed. Briefly stated, in the preferred embodiment of the present invention, various parameters of the sub-systems in a HVAC system are monitored and made alterable or changeable. These parameters are transmitted to and controlled by a flexible process controller which thereafter cooperates with a motor drive controller. Logic incident to and resident in the flexible process controller consider the various parameters monitored and allow the user or the system to minimize power consumption amongst one or more of the sub-systems while maximizing efficiency and operability.