Real time remote sensing pressure control system using periodically sampled remote sensors

A water system of the type that includes at least one primary pump, at least one heat exchanging device, at least one variable speed secondary pump, a return pipe connected to the suction side of said primary pump, a supply pipe connected to the discharge side of said variable speed secondary pump, at least one system load having a supply and return line, said water system comprising:

• (a) a local differential pressure sensor connected to said supply pipe and to said return pipe, said local differential pressure sensor including an output that generates a first signal related to the differential pressure across the local differential pressure sensor,
• (b) a remote differential pressure sensor connected to the supply and return line at each of said at least one system load, said remote differential pressure including an output that generates a second signal related to the differential pressure across the remote differential pressure sensor;
• (c) a remote control panel located near each of said at least one system load, said remote control panel having a second processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said second processing circuit being configured to receive the second signal generated by the output of said remote differential pressure sensor, said second processing circuit additionally having a communications output device that transmits information corresponding to said second signal;
• and
• (d) a local control panel having a first processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said first processing circuit further including a controller that controls the speed of a pump, said first processing circuit being configured to receive the first signal generated by the output of said local differential pressure sensor, said first processing circuit additionally having a communications input device that receives said information transmitted by said communications output device at the remote control panel, said first processing circuit being configured to provide a setpoint for each of said at least one system load, wherein the setpoint represents the desired pressure for that system load, said first processing circuit being configured to determine the magnitude of deviation between the actual differential pressure sensed by each said remote differential pressure sensor and said setpoint for each corresponding system load based upon the information received from said communications output device at the remote control panel and its associated setpoint, said deviation creating a third signal, said first processing circuit using said third signal to modify said first signal to create a fourth signal, said first processing circuit being configured to control the speed of said at least one variable speed secondary pump based upon the value of said fourth signal.

A water system of the type that includes at least one primary pump, at least one heat exchanging device, at least one variable speed secondary pump, a return pipe connected to the suction side of said primary pump, a supply pipe connected to the discharge side of said variable speed secondary pump, at least one zone containing a system load having a supply and return line, said water system comprising:

• (a) a local differential pressure sensor connected to said supply pipe and to said return pipe, said local differential pressure sensor including an output that generates a first signal related to the differential pressure across the local differential pressure sensor;
• (b) a remote differential pressure sensor connected to the supply and return line at each of said at least one zone, said remote differential pressure including and output that generates a second signal related to the differential pressure across the remote differential pressure sensor;
• (c) a remote control panel located near each of said at least one zone, said remote control panel having a second processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said second processing circuit being configured to receive the second signal generated by the output of said remote differential pressure sensor, said second processing circuit additionally having a communications output device that transmits information corresponding to said second signal;
• and
• (d) a local control panel having a first processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said first processing circuit further including a controller that controls the speed of a pump, said first processing circuit being configured to receive the first signal generated by the output of said local differential pressure sensor, said first processing circuit additionally having a communications input device that receives said information transmitted by said communications output device at the remote control panel, said first processing circuit being configured to provide a setpoint for each of said at least one zone, wherein the setpoint represents the desired pressure for that zone, said first processing circuit being configured to determine the zone requiring the greatest amount of correction to bring the actual differential pressure of a particular zone to its set point, and to create a third signal corresponding to the magnitude of said greatest amount of correction required based upon the information received form said communications output device at the remote control panel and its associated setpoint, said first processing circuit using said third signal to modify said first signal to create a fourth signal, said first processing circuit being configured to control the speed of said at least one variable speed secondary pump based upon the value of said fourth signal.

A water system of the type that includes at least one primary pump, at least one heat exchanging device, at least one variable speed secondary pump, a return pipe connected to the suction side of said primary pump, a supply pipe connected to the discharge side of said variable speed secondary pump, at least one zone containing a system load having a supply and return line, said water system comprising:

• (a) a local differential pressure sensor connected to said supply pipe and to said return pipe, said local differential pressure sensor including an output that generates a first signal related to the differential pressure across the local differential pressure sensor.
• (b) a remote differential pressure sensor connected to the supply and return line at each of said at least one zone, said remote differential pressure including an output that generates a second signal related to the differential pressure across the remote differential pressure sensor;
• (c) a remote control panel located near each of said at least one zone, said remote control panel having a second processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said second processing circuit being configured to receive the second signal generated by the output of said remote differential pressure sensor, said second processing circuit additionally having a communications output device that transmits information corresponding to said second signal;
• and
• (d) a local control panel having a first processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said first processing circuit further including a controller that controls the speed of a pump, said first processing circuit being configured to receive the first signal generated by the output of said local differential pressure sensor, said first processing circuit additionally having a communications input device that receives said information transmitted by said communications output device at the remote control panel, said first processing circuit being configured to provide a setpoint for each of said at least one zone, wherein the setpoint represents the desired pressure for that zone, said first processing circuit being configured to determine the zone having the highest load, and to create a third signal corresponding to the magnitude of said highest load based upon the information received from said communications output device at the remote control panel, said first processing circuit using said third signal to modify said first signal to create a fourth signal, said first processing circuit being configured to control the speed of said at least one variable speed secondary pump based upon the value of said fourth signal.

A water system of the type that includes at least one primary pump, at least one heat exchanging device, at least one variable speed secondary pump, a supply pipe connected to the discharge side of said variable speed secondary pump, at least one system load having a supply line, said water system comprising:

• (a) a local pressure sensor connected to said supply pipe, said local pressure sensor including an output that generated a first signal related to the pressure at the local pressure sensor;
• (b) a remote pressure sensor connected to the supply line at each of said at least one system load, said remote pressure including an output that generates a second signal related to the pressure at the remote pressure sensor;
• (c) a remote control panel located near each of said at least one system load, said remote control panel having a second processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said second processing circuit being configured to receive the second signal generated by the output of said remote pressure sensor, said second processing circuit additionally having a communications output device that periodically transmits information corresponding to said second signal;
• and
• (d) a local control panel having a first processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said first processing circuit further including a controller that controls the speed of a pump, said first processing circuit being configured to receive in real time the first signal generated by the output of said local pressure sensor, said first processing circuit additionally having a communications input device that periodically receives said information transmitted by said communications output device at the remote control panel, said first processing circuit being configured to control the speed of said at least one variable speed secondary pump based upon the values of said first and second signals.

A method for controlling a water system of the type that includes at least one primary pump, at least one heat exchanging device, at least one variable speed secondary pump, a return pipe connected to the suction side of said primary pump, a supply pipe connected to the discharge side of said variable speed secondary pump, at least one system load having a supply and return line, said water system comprising:

• (a) measuring the differential pressure across said supply and return pipes and creating a first signal related to this local differential pressure;
• (b) measuring the differential pressure across said supply and return lines at each of said at least one system load and creating a second signal related to this remote differential pressure;
• (c) communicating said second signal at periodic intervals to a control panel;
• (d) communicating said first signal in real time to said control panel;
• and
• (e) controlling the speed of said at least one variable speed secondary pump based upon the values of said first and second signals.

A method for controlling a water system of the type that includes at least one primary pump, at least one heat exchanging device, at least one variable speed secondary pump, a supply pipe connected to the discharge side of said variable speed secondary pump, at least one system load having a supply line, said water system comprising:

• (a) measuring the pressure at said supply pipe and creating a first signal related to this local pressure;
• (b) measuring the pressure at said supply line at each of said at least one system load and creating a second signal related to this remote pressure;
• (c) communicating said second signal at periodic intervals to a control panel;
• (d) communicating said first signal in real time to said control panel;
• and
• (e) controlling the speed of said at least one variable speed secondary pump based upon the values of said first and second signals.

A water system of the type that includes a plurality of zones each containing a water source, at least one variable speed pump per said water source, at least one system load, a pipe from each of said plurality of water sources to said at least one system load, said water system comprising:

• (a) a first pressure sensor connected to one of said pipes, said first pressure sensor having an output that generates a first signal related to the pressure at said first pressure sensor;
• (b) a master control panel associated with a first one of said zones, said master control panel having a first processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said processing circuit further including a controller that controls the speed of a pump, said first processing circuit being configured to receive said first signal, said first processing circuit having a communications input/output device that transmits and receives information related to said water system, said first processing circuit being configured to provide a setpoint for said first zone;
• (c) a second pressure sensor connected to another of said pipes, said second pressure sensor having an output that generates a second signal related to the pressure at said second pressure sensor;
• (d) at least one slave control panel, the first one of said slave control panels being associated with a second one of said zones, said first slave control panel having a second processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said second processing circuit further including a controller that controls the speed of a pump, said second processing circuit being configured to receive said second signal, said second processing circuit having a communications input/output device that transmits and receives information related to said water system, said second processing circuit being configured to provide a setpoint for said second zone;
• (e) a data highway that communicates information to and from each of said master and slave control panels;
• (f) said first processing circuit additionally being configured to determine each of the setpoints and actual pressures for all zones within said water system, then to determine a bias value needed by said water system so that said at least one variable speed pump that is presently operating is controlled in a manner to satisfy the setpoints at all of said zones, said first processing circuit being configured to transmit said bias value to said at least one slave control panel via the data highway, said first processing circuit using said bias value to modify the setpoint for said first zone accordingly to control said at least one variable speed pump associated with said first zone;
• and
• (g) each of said at least one slave control panel's second processing circuit additionally being configured to receive said bias value from the data highway, said second processing circuit using said bias value to modify the setpoint for said second zone accordingly to control said at least one variable speed pump associated with said second zone.

A method for controlling a water system of the type that includes a plurality of zones each containing a water source, at least one variable speed pump per said water source, at least one system load, a pipe from each of said plurality of water sources to said at least one system load, said method comprising the steps of:

• (a) measuring the pressure at one of said pipes associated with a first one of said zones and providing a first setpoint for said first zone;
• (b) measuring the pressure at another of said pipes associated with a second of said zones and providing a second setpoint for said second zone;
• and
• (c) determining each of the setpoints and actual pressures for all zones within said water system, then determining a bias value needed by said water system so that said at least one variable speed pump that is presently operating is controlled in a manner to satisfy the setpoints at all of said zones, and modifying the setpoint for each of said zones accordingly, utilizing said bias value.

A fluid pumping system of the type having a pumping station that includes at least one variable speed pump, a discharge pipe connected to said pumping station, a system load having a supply line, said discharge pipe being connected to said supply line, said fluid pumping system comprising:

• (a) a first pressure sensor connected to said discharge pipe, said first pressure sensor including an output that generates a first signal related to the pressure across the first pressure sensor;
• (b) a second pressure sensor connected to the supply line at said system load, said second pressure sensor including an output that generates a second signal related to the pressure across the second pressure sensor;
• (c) a second control panel located near said system load, said second control panel having a second processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said second processing circuit being configured to receive the second signal generated by the output of said second pressure sensor, said second processing circuit additionally having a communications output device that transmits information corresponding to said second signal;
• and
• (d) a first control panel having a first processing circuit which includes a memory circuit, input/output circuits, and a clock circuit that measures real time, said first processing circuit further including a controller that controls the speed of a pump, said first processing circuit being configured to receive the first signal generated by the output of said first pressure sensor, said first processing circuit additionally having a communications input device that receives said information transmitted by said communications output device at the second control panel, said first processing circuit being configured to control the speed of said at least one variable speed secondary pump based upon the values of said first and second signals, said first processing circuit using a predetermined setpoint at which the desired pressure of the system load is to be maintained, said first signal being used as a bias for said setpoint.