초록 ▼

An electronic process controller is disclosed having automatically bumpless operation. Changes such as transfer between manual and automatic modes, switching between set point sources and adjustment of control parameter values are all accomplished bumplessly with the aid of a settle circuit which ad

An electronic process controller is disclosed having automatically bumpless operation. Changes such as transfer between manual and automatic modes, switching between set point sources and adjustment of control parameter values are all accomplished bumplessly with the aid of a settle circuit which adjusts the automatic control signal for bumpless switching while the manual memory freezes the process control signal at its last value before the change was initiated.

대표청구항 ▼

An improved automatic process controller having adjustable parameters operable in manual and automatic modes of the type having: automatic control means for generating an automatic control signal during the automatic mode related to the deviation of a process value signal from a set-point signal, ma

An improved automatic process controller having adjustable parameters operable in manual and automatic modes of the type having: automatic control means for generating an automatic control signal during the automatic mode related to the deviation of a process value signal from a set-point signal, manual memory means for generating an adjustable manual control signal during the manual mode, an output switch for selectively applying one of the control signals to the process to be controlled, means to cause the automatic control signal to track the signal applied to the process during the manual mode, and means to cause the manual control signal to track the signal applied to the process during the automatic mode, wherein the improvement comprises: bumpless adjust means for initiating a change in the operation of the automatic control means; first logic means responsive to actuation of the bumpless adjust means to operate the output switch to apply the manual control signal to the process; a settle circuit for causing the automatic control signal to become equal to the signal applied to the process only when actuated; second logic means responsive to actuation of the bumpless adjust means for generating a settle time period and for activating the settle circuit during the settle time period; and third logic means for operating the output switch to apply the automatic control signal to the process at the end of the settle time period.