Facility management system with improved return to automatic control

A control system of the type which controls a parameter to maintain said parameter at a given set point, said control system comprising:

• device means responsive to an automatic control signal when under automatic control or a manually selected control signal when under manual control for effecting said parameter;
• sensor means for sensing the level of said parameter and providing a feedback signal responsive to said sensed parameter level;
• automatic control means coupled to said sensor means and being responsive to being coupled to said device means for generating an automatic control signal for said device means having a level derived from the sum of integral, derivative, and proportional actions to said feedback signal for automatically controlling said device means;
• interface means coupled between said automatic control means and said device means for coupling said automatic control means to said device means to place said device means under automatic control and for decoupling said automatic control means from said device means for placing said device means under manual control of a manually selected control signal;
• and
• said automatic control means being responsive to being decoupled from said device means by said interface means for terminating the generation of said automatic control signal and arranged for storing the last level of said automatic control signal provided to said device means prior to being decoupled from said device means from said interface means and for storing the last level of said feedback signal received from said sensor means prior to being decoupled from said device means by said interface means wherein said automatic control means is responsive to being recoupled to said device means by said interface means for providing said automatic control signal to said device means at an initial level based upon said stored level of said automatic control signal plus a proportionality factor multiplied by the current feedback signal minus the stored level of said feedback signal.

A control system of the type which controls a parameter to maintain said parameter at a given set point, said control system comprising:

• device means responsive to an automatic control signal when under automatic control or a manually selected control signal when under manual control for effecting said parameter;
• sensor means for sensing the level of said parameter and providing a feedback signal responsive to said sensed parameter level;
• automatic control means coupled to said sensor means and being responsive to being coupled to said device means for generating an automatic control signal for said device means having a level derived from the sum of integral, derivative, and proportional actions to said feedback signal for automatically controlling said device means;
• interface means coupled between said automatic control means and said device means for coupling said automatic control means to said device means to place said device means under automatic control and for decoupling said automatic control means from said device means for placing said device means under manual control of a manually selected control signal;
• and
• said automatic control means being responsive to being decoupled from said device means by said interface means for terminating the generation of said automatic control signal, and arranged for storing the last level of said automatic control signal provided to said device means prior to being decoupled from said device means by said interface means and wherein said automatic control means is responsive to being recoupled to said device means by said interface means for providing said automatic control signal to said device means at an initial level based upon said stored level of said automatic control signal, and arranged to determine the level of said automatic control signal at periodic time intervals, and wherein said initial level is equal to the sum of said stored level and said proportional action during the current time interval.

A facility management system of the type which controls a parameter to maintain said parameter at a given set point, said control system comprising:

• a field device responsive to an automatic control signal when under automatic control or a manually selected control signal when under manual control for effecting said parameter;
• a remote sensor for sensing the level of said parameter and providing a feedback signal responsive to said sensed parameter level;
• automatic control means coupled to said remote sensor and being responsive to being coupled to said field device for generating an automatic control signal for said field device having a level derived from the sum of integral, derivative, and proportional actions to said feedback signal for automatically controlling said field device;
• interface means coupled between said automatic control means and said device means for coupling said automatic control means to said device means to place said device means under automatic control and for decoupling said automatic control means from said device means for placing said device means under manual control of a manually selected control signal;
• and
• said automatic control means being responsive to being decoupled from said field device by said interface means for terminating the generation of said automatic control signal and arranged for providing said automatic control signal to said field device at an initial level based upon the level of said manually selected control signal upon being recoupled to said field device by said interface means.

A facility management system of the type which controls a parameter to maintain said parameter at a given set point, said control system comprising:

• a field device responsive to an automatic control signal when under automatic control or a manually selected control signal when under manual control for effecting said parameter;
• a remote sensor for sensing the level of said parameter and providing a feedback signal responsive to said sensed parameter level;
• automatic control means coupled to said remote sensor and being responsive to being coupled to said field device for generating an automatic control signal for said field device having a level derived from the sum of integral, derivative, and proportional actions to said feedback signal for automatically controlling said field device;
• interface means coupled between said automatic control means and said device means for coupling said automatic control means to said device means to place said device means under automatic control and for decoupling said automatic control means from said device means for placing said device means under manual control of a manually selected control signal;
• and
• said automatic control means being responsive to being decoupled from said field device by said interface means for terminating the generation of said automatic control signal and arranged for storing the last level of said automatic control signal provided to said device means prior to being decoupled from said device means by said interface means and for storing the last level of said feedback signal received from said sensor means prior to being decoupled from said device means from said interface means wherein said automatic control means is responsive to being recoupled to said device means by said interface means for providing said automatic control signal to said device means at an initial level based upon said stored level of said automatic control signal plus a proportionality factor multiplied by the current feedback signal minus the stored level of said feedback signal.

A facility management system of the type which controls a parameter to maintain said parameter at a given set point, said control system comprising:

• a field device responsive to an automatic control signal when under automatic control or a manually selected control signal when under manual control for effecting said parameter;
• a remote sensor for sensing the level of said parameter and providing a feedback signal responsive to said sensed parameter level;
• automatic control means coupled to said remote sensor and being responsive to being coupled to said field device for generating an automatic control signal for said field device having a level derived from the sum of integral, derivative, and proportional actions to said feedback signal for automatically controlling said field device;
• and
• interface means coupled between said automatic control means and said device means for coupling said automatic control means to said device means to place said device means under automatic control and for decoupling said automatic control means from said device means for placing said device means under manual control of a manually selected control signal;
• said automatic control means being responsive to being decoupled from said field device by said interface means for terminating the generation of said automatic control signal, arranged for storing the last level of said automatic control signal provided to said field device prior to being decoupled from said field device by said interface means and wherein said automatic control means is responsive to being recoupled to said field device by said interface means for providing said automatic control signal to said device means at an initial level based upon said stored level of said automatic control signal, and arranged to determine the level of said automatic control signal at periodic time intervals, and wherein said initial level is equal to the sum of said stored level and said proportional action during the current time interval.

A facility management system of the type which controls an environment parameter to maintain said parameter at a given set point, said facility management system comprising:

• a field device responsive to an automatic control signal when under automatic control or a manually selected control signal when under manual control for effecting said environmental parameter;
• a remote sensor for sensing the level of said environmental parameter and providing a feedback signal responsive to the sensed parameter level;
• automatic control means coupled to said remote sensor and responsive to being coupled to said field device for generating an automatic control signal for said field device having a level derived from the sum of integral, derivative, and proportional actions to said feedback signal to place said field device under automatic control;
• first interface means for coupling said automatic control means to and decoupling said automatic control means from said field device, said first interface means being arranged to provide said field device with said manually selected control signals upon decoupling said automatic control means from said field device;
• said automatic control means being responsive to being decoupled from said field device by said first interface means when said field device is under manual control for terminatng the generation of said automatic control signal and being responsive to being recoupled to said field device by said first interface means for providing said automatic control signal to said field device at a first initial level based upon the level of said manually selected control signal upon being recoupled to said field device;
• and second interface means coupled between said first interface means and said field device for coupling said first interface means to said field device, said second interface means being arranged for converting said automatic control signals to analog automatic control signals and including decoupling means for decoupling said first interface means and said automatic control means from said field device, and wherein said automatic control means is responsive to being decoupled from said field device by said second interface means for providing said automatic control signals to said second interface means during periodic intervals at levels based upon the level of said automatic control signal provide to said field device at the time said automatic control means was decoupled from said field device plus a proportionality factor multiplied by the current feedback signal minus the feedback signal at the time said automatic control means was decoupled from said field device.