Thermal dispersion flow meter with fluid leak detection and freeze burst prevention
11608618 · 2023-03-21
Assignee
Inventors
- Robert Trescott (San Marcos, CA, US)
- Scott Shaw (Brentwood, TN, US)
- Scott Pallais (Escondido, CA, US)
- Kenneth Fox (Escondido, CA, US)
Cpc classification
E03B7/08
FIXED CONSTRUCTIONS
E03B7/071
FIXED CONSTRUCTIONS
G01F1/6847
PHYSICS
E03B7/078
FIXED CONSTRUCTIONS
G01K13/02
PHYSICS
Y02A20/15
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
E03B7/07
FIXED CONSTRUCTIONS
E03B7/08
FIXED CONSTRUCTIONS
G01M3/28
PHYSICS
G01K13/02
PHYSICS
G01F1/684
PHYSICS
G01F1/688
PHYSICS
Abstract
A non-invasive thermal dispersion flow meter with chronometric monitor for fluid leak detection includes a heater, an ambient temperature sensor and a flow rate sensor which are configured to sense the temperature of a fluid in a conduit, and then monitor the flow of that fluid through the conduit. Based upon the ambient temperature sensor readings, the flow rate sensor and heater may be adjusted to optimize the operation of the system to detect leaks. Based on the sensor readings, the flow may be adjusted to prevent damage and leaks by relieving the system of excess pressure. Geographic location, occupancy sensors and occupant identifiers are used to control the system to facilitate operation and minimize leak damage when occupants are away.
Claims
1. A fluid leak detection and freeze prevention system, comprising: a heating system thermally coupled to a fluid conduit system having a fluid; a primary sensor package configured to measure a primary sensor package fluid flow rate and a primary sensor package fluid temperature of said fluid in said fluid conduit system; and a secondary sensor package configured to measure a secondary sensor package fluid flow rate and a secondary sensor package fluid temperature of said fluid in said fluid conduit system, wherein detection of a freeze condition activates said heating system to add heat energy to said fluid in said fluid conduit to prevent said fluid from freezing, wherein said freeze condition exists when said primary sensor package fluid temperature is at a primary sensor package first threshold temperature and said freeze condition exists when said primary sensor package fluid temperature is at or below a primary sensor package second threshold temperature for an elapsed time, said primary sensor package first threshold temperature is lower than said primary sensor package second threshold temperature, wherein a leak condition exists when said primary sensor package fluid flow rate exceeds a threshold fluid flow rate for an elapsed trip time, wherein said freeze condition exists when said secondary sensor package fluid temperature is at a secondary sensor package first threshold temperature and said freeze condition exists when said secondary sensor package fluid temperature is at or below a secondary sensor package threshold temperature for an elapsed time, said secondary sensor package first threshold temperature is lower than said secondary sensor package second threshold temperature, wherein said primary sensor package comprises a primary sensor package temperature sensing element and a primary sensor package heating element, and wherein said heating system comprises said primary sensor package heating element, and wherein said secondary sensor package comprises a secondary sensor package temperature sensing element and a secondary sensor package heating element, and wherein said heating system further comprises said secondary sensor package heating element.
2. The fluid leak detection and freeze prevention system of claim 1, further comprising: an external environment temperature sensor configured to measure an outdoor temperature of a structure housing said fluid conduit system; and wherein said freeze condition exists when said outdoor temperature is at an external environment temperature sensor first threshold temperature and said freeze condition exists when said outdoor temperature is at or below an external environment temperature sensor second threshold temperature for an elapsed time, said external environment temperature sensor first threshold temperature is lower than said external environment temperature sensor second threshold temperature.
3. The fluid leak detection and freeze prevention system of claim 2, further comprising: a local environment temperature sensor configured to measure an indoor temperature of said structure housing said fluid conduit system; and wherein said freeze condition exists when said indoor temperature is at a local environment temperature sensor first threshold temperature and said freeze condition exists when said indoor temperature is at or below a local environment temperature sensor second threshold temperature for an elapsed time, said first threshold temperature is lower than said second threshold temperature.
4. The fluid leak detection and freeze prevention system of claim 1, wherein said heating system comprises: a heated recirculation circuit configured to heat and circulate said fluid within said fluid conduit system.
5. The fluid leak detection and freeze prevention system of claim 4, wherein said heated recirculation circuit comprises: an exhaust solenoid in fluid communication with said fluid conduit system; a return solenoid in fluid communication with said fluid conduit system; a recirculation conduit between said exhaust solenoid and said return solenoid, said recirculation conduit is in fluid communication with said fluid conduit system; a heating element thermally coupled to said recirculation conduit; and a recirculation pump in fluid communication with said recirculation conduit and said fluid conduit system.
6. The fluid leak detection and freeze prevention system of claim 1, further comprising: a fluid leak detector comprising a probe and a controller, said controller is configured to monitor a fluid flow rate of said fluid and increasing a timeout counter when the fluid flow rate monitored by the controller is above a trip level fluid flow rate and resetting the timeout counter to zero when the fluid flow rate monitored by the controller is below the trip level fluid flow rate, wherein a leak is detected when the timeout counter exceeds a timeout value.
Description
BRIEF DESCRIPTION OF THE FIGURES
(1) The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which reference characters refer to similar parts, and in which:
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DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
(33) This invention relates to an electronic thermal monitor system intended to measure fluid flow within a conduit or pipe, by clamping directly to the outside of a pipe or onto a thermally conductive heat transfer medium between the fluid and the system.
(34) Referring to
(35) In an exemplary embodiment, this invention is discussed in conjunction with a typical thin wall copper pipe section commonly found in commercial and residential plumbing systems that form the water supply line. Since copper is an excellent conductor of temperature, this meter infers the water temperature by measuring the outside skin temperature of the pipe section. Another embodiment is to measure fluid flow within a confined conduit whereby the thermally conductive transfer medium is embedded within the conduit and allows for unimpeded and low heat measurements of fluids such as gasoline, diesel oil, liquid slurries, as well as gases such as air or nitrogen.
(36) The thermal conduction means in the exemplary embodiment are clamps which mount to the pipe and form not only a mechanical connection between the meter and the pipe, but a thermal connection as well. The clamps are designed to transfer heat to and from the meter and the water within the pipe. The pipe may be any shape to contain the fluid and allow a thermal conduction means to the fluid within.
(37) In the exemplary embodiment there is one upstream temperature reference clamp that contains an integrated temperature sensing element, such as a thermistor, thermocouple, or resistance temperature detector (“RTD”), which reads the current temperature of the pipe and fluid within. A second sensor clamp, mounted downstream from the reference, also contains an integrated temperature sensing element and a resistive heater which transfers heat energy into the pipe and the water within. This clamp performs the actual flow rate measurement.
(38) Referring to
(39) While
(40) Additionally,
(41) Referring to
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(46) If the temperature has been calibrated 258, then the system will check for the presence of a time delay 266. If the delay time value has not been reached, the system will return to step 256 to continue heating the RTD. If the delay time value has been reached 266, the system will add time to the accumulator and record flow 268. If the accumulator has not reached its maximum value 270, the system will return to step 256 where it will continue to heat the RTD. If the accumulator has reached its maximum value 270, the system will compare the calculated flow to the flow trip point 272. If the trip point has not been reached 272, the system will return to step 268 where it will add time to the accumulator and record flow. If the trip point has been reached 272, the system will activate functions such as an alarm, an indicator, and automatic valve closure 274. It should be appreciated by someone skilled in the art that many different functions may be controlled by the system and the functions listed above are not the exclusive functions of the system.
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(48) The present invention as shown in
(49) Specifically, one aspect of occupant detection includes geo-fencing detection using standard portable electronics such as a cellular telephone having an application which senses the geographic location of an occupant, and compares that location with a user-determined geographical range about the property being controlled. When the occupant is within the user-determined geographical range, the system will operate as the occupant is present. On the other hand, when the geographic location of an occupant is outside the user-determined geographical range, the system will automatically switch to an AWAY mode, thereby providing a heightened level of leak detection and interruption as preset by the occupant.
(50) In use, customers of system 900 (shown in
(51) If enabled, the server would then perform an automatic action that selects the appropriate HOME/AWAY selection according to GPS data passed on to the server, from the occupant's cell phone device.
(52) In this configuration, the application would be running as a background task reading the GPS location service of the cell phone every few minutes. The occupant can set localization GPS coordinates of the leak detection system 900 and then pass those values on to the host database and system 900. An algorithm reads the localized GPS data and forms a virtual perimeter around those coordinates which are also saved with that occupant's data; this has been referred herein as the “geo-fencing boundary.” The occupant's mobile application's background task routinely sends identification and present GPS values. The database runs a service that compares the present GPS data to the geo-fencing boundary perimeter coordinates, and determines an inclusive or exclusive relationship of the virtual boundary; the occupant is either within the boundary or outside the boundary.
(53) Home Mode would be transmitted to the leak detection system 900 if the following conditions exist:
(54) 1—This function is activated and enabled;
(55) 2—The GPS data is available;
(56) 3—The cell phone can make internet connectivity;
(57) 4—The system can identify the occupant's system 900;
(58) 5—The system 900 must have previously stored its GPS local data;
(59) 6—The database determines an inclusive relationship within the virtual boundary;
(60) 7—According to the running database, the HOME mode must not already be selected; and
(61) 8—Any other registered occupant is already recorded to be within the virtual boundary.
(62) Similarly Away Mode would be transmitted to the leak detection system 900 if the following conditions exist:
(63) 1—This function is activated and enabled;
(64) 2—The GPS data is available;
(65) 3—The cell phone can make internet connectivity;
(66) 4—The system can identify the occupant's LDS system;
(67) 5—The system 900 must have previously stored its GPS local data;
(68) 6—The database determines an exclusive relationship outside the virtual boundary;
(69) 7—According to the running database, the AWAY mode must not already be selected; and
(70) 8—All registered occupants are outside of the virtual boundary.
(71) In addition to the portable electronics geographic location, the leak detection system may incorporate alternative occupant detectors. For instance, the system may incorporate Radio Frequency Identification (RFID) tags coupled with RFID readers. In use, an occupant simply scans the RFID tag when entering a property to activate the system in the HOME mode. Similarly, when the occupant leaves the property, another scan of the RFID tag switches the system to the AWAY mode. Alternatively, multiple RFID readers may be placed throughout the property which, during the normal use of the property by the occupant, will sense the RFID tag presence and maintain the HOME mode. When the RFID tag is no longer readable by any RFID reader within the property, the system will automatically switch to AWAY mode.
(72) Another alternative occupant detection system input into the display 304 may include an optical or infrared sensor which senses the physical presence of an occupant within the property. This sensor will simply alert the system of the presence of a person within the property and enter the HOME mode of operation.
(73) Yet another input into the display 304 which can assist in the determination of the presence of an occupant is a temporary bypass timer which can be manually set or triggered. This physical timer may have a fixed time period such as a pushbutton that triggers a 30 minute timer, or may be adjustable such as a dial timer that can be set from 0 to 60 minutes. The timer will allow an occupant, such as a service person (housekeeper, gardener, service technician, etc.), to manually switch the system to the HOME mode as needed, and the timer will automatically return to the AWAY mode with no further action needed. This process can be repeated multiple times of the timer period is insufficient for that particular occupant, but absent an affirmative retriggering of the timer, the system will automatically return to the AWAY mode when the timer expires. a geolocation system input to display 304. Additionally, a manual override controller such as a manually activated timer device may be incorporated to provide a manual temporary bypass feature to place the system in the HOME mode.
An Alternative Embodiment
(74) Now referring to
(75) This alternative embodiment uses heat conduction, propagation, and time to determine if there is liquid flow within an enclosed metallic conduit 524.
(76) In normal operation, this embodiment works in an intermittent operation. After a calibrated tune has elapsed, the heater 518 becomes energized, which forces heat energy into the conduit 524. The controller 502 would read the temperature sensor 520 just prior to heater 518 activation, and stored that value for further calculations. Conducted heat from the metallic conduit 524 will readily propagate from the center of the heat source 518 and outward eventually reaching the temperature sensor 522. The amount of time it takes for the heat to propagate to the temperature sensor 520 is recorded in the controller 502 and is a direct function of the liquid flow 534 within the conduit 524. Long propagation times reflect large effective flow rates.
(77) The heater power is removed after a predetermined “no-flow” condition timer expires. The controller 502 will continue to read the temperature sensor 520 to continually analyze the heat propagation and lock onto a value that represents the peak temperature attained. This value is also a direct function of the liquid flow 534 within the conduit 524. Higher peak temperatures represent low effective flow rates, as the heater 518 is simply creating a no flow “pocket” of liquid, with little to no convective forces to carry away the applied heat energy.
(78) Finally, after a predetermined amount of time has elapsed, the controller 502 acquires one final reading from the temperature sensor 520 and compares it to the previously saved value before the heater 518 was activated. The ratio of the before and after temperature readings is also a direct function of the liquid flow 534 within the conduit 524. The closer the two values are, the greater the effective flow rate is within the conduit 524 as the flowing liquid 534 is restoring the ambient fluid temperature to nullify the effects of the previously added heat energy.
(79) All of the calculated temperature and time variables are scored within an algorithm that normalizes the effective flow rate with respect to ambient temperature and conduit/heater 524/518 thermal conductivity. The calculated score determines the liquid flow 534 rate, then the controller 502 records that rate, powers down for a short period of time as determined by the Master Time value 526, and allows the heater 518 and temperature sensor 520 to return to ambient conditions through natural convection.
(80) As the system continues to move through heating and cooling cycles, the running status is accumulated. If the flow rate over all the cycles has not provided a single “no-flow” score, the system will enter an alarm state where it will either activate a relay 514, create an audible alert 512, or do both. The alarm may be cancelled by stopping the fluid flow or by switching to another mode of operation 510, either HOME or AWAY, which effectively resets all timers and scoring status results.
(81) The heater 518 and temperature sensor 520 must be properly affixed to the conduit 524 to ensure consistent results over a long period of time measured in years. The heater 518 is a flexible silicone band which can wrap around the conduit 524 and be held in place with a self-adhesive vulcanizing wrapping tape specifically designed to seal out moisture and provide continuous pressure on the heater 518 ensuring optimal thermal conductivity over time. It is to be appreciated by someone skilled in the art that many heater 518 designs exist that will satisfy the requirements of the system. The temperature sensor 520 also requires the same treatment during installation to ensure that the conduit 524 temperature is properly reported. It is also imperative that the entire heater/sensor 518/520 section, and a few inches beyond, be enclosed in thermal insulation 516. This prevents ambient or environmental air currents from affecting the calibrated flow readings by heating or cooling effects that are not the direct result of the fluid flow 534 within the conduit 524.
(82) Intermittent operation of the heater 518 is required to provide the extended “no-flow” time period with an opportunity equilibrate with ambient conditions. Otherwise, the heater 518 and temperature sensor 520 would create a localized “hot water heater” within the test section of the conduit 524. Therefore, this device may not be used to measure flow rate or flow total as do other technologies, such as Thermal Mass Flow Meters. While this system is currently described to operate through a closed section of copper tubing/pipe 524, it may also operate through plastic conduit provided that the test section has in-molded metal plates or “shoes” within. The heater 518 and temperature sensor 520 requires direct thermal conduction of the fluid within in order to perform the same operation of an all-metal design.
(83) An AC/DC power supply 504 may be used since the heater 518 requires significant energy output (>12 Watts) to perform its tests accurately and reliably. Alarm panel interfacing may also be expanded to include both wired and/or wireless operation for command/control facilities.
Installation and Calibration
(84) This alternative embodiment of the present invention requires about 8″-10″ of clean copper pipe 524 to properly assemble the test section. The section of water pipe 524 selected should pass all incoming supply to the entire structure and should not be located outside where protecting the heater 518 and temperature sensor 520 elements would be impossible,
(85) Once the heater 518 and temperature sensor 520 have been properly installed and the wiring and power have been completed, the device must be calibrated to the particular installation. Before activating the calibration function, all water flow in the test section must be halted.
(86) The calibration function can be activated by an on-board switch, or wireless command, or a unique mode selection. During calibration, the unit will activate the heater 518. When the temperature sensor 520 records a temperature increase of 4.degree. F.-10.degree. F., the time which passes during this test is recorded by the controller 502 and stored for all future heater timing variables. Calibration finishes automatically and the system will be able to alert the installer if there is a problem or start performing normal operations if all is well.
(87) This invention is a fluid flow meter with many applications and embodiments incorporating a unique method of flow measurement utilizing noninvasive thermal anemometry. The use of a Wheatstone Bridge greatly increases the system sensitivity and accuracy allowing it to be used in many applications.
Freeze Burst Detection and Prevention
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(89) The external environment temperature sensor 704 detects temperature changes in the external, or ambient, environment. The sensor 704 feeds the resistance measurements to the signal processor 710 to create a digital signal of the temperature data which is fed to a microprocessor 712 where it is analyzed to determine the temperature by comparing the temperature data to the data stored in the control ROM and flash memory 716.
(90) The flow and temperature data from the sensors are further analyzed by the microprocessor 712 to determine the state of the fluid by comparing the flow and temperature data of the sensors to the user-inputted data stored in the control ROM and flash memory 716. The microprocessor 712 will perform various functions 714, such as open a valve, energize a relay, illuminate an LED, or create an audible alarm, when the measured flow and temperature data triggers a response based on the user data stored in memory 716.
(91) The diagram shows an isolation valve 722 for interrupting fluid flow into the conduit system 720, a relief valve 724 for releasing the flow of fluid in the system through a drainage pipe 726, and an air valve 728 to allow atmospheric air to enter into the system. Air valve 728 is located at a high point in the system and relief valve 724 is located at a low point near the end of the system, The microprocessor 712 will open relief valve 724 when a value stored in control ROM or flash memory 716 is reached by the sensors 702, 704, and/or 706, For example, at 32 degrees Fahrenheit water freezes and expands, increasing its volume. Therefore if the fluid is water and the temperature is at 32 degrees Fahrenheit a determination that the water is expanding will be made and the relief valve 724 will be opened. If the value is at or below a secondary value stored in control ROM or flash memory 716, such as severe freezing conditions for water, microprocessor 712 will close isolation valve 722 to prevent water from entering the system and open relief valve 724 to evacuate the water in the system. The air valve 726 is then opened to allow atmospheric air to enter the system to aid the evacuation of fluid and prevent the formation of a vacuum. The valves will be installed in locations to allow the most efficient fluid flow through the system. The control ROM and flash memory 716 can store several values for different trigger points such as the temperature difference between inlet and outlet fluid temperatures.
(92) In addition, the primary temperature sensor package 702 and the secondary temperature sensor package 706 may be utilized to raise the temperature of the fluid to prevent the fluid within the fluid conduit system 720 from freezing. It is contemplated that the primary temperature sensor package 702 and secondary temperature sensor package 706 includes a temperature sensing element and a heating element, as shown in
(93) The flow and temperature data from the sensors are further analyzed by the microprocessor 712 to determine the state of the fluid by comparing the flow and temperature data of the sensors to the user-inputted data stored in the control ROM and flash memory 716. The microprocessor 712 will turn on the heating element of the primary temperature sensor package 702 and the secondary temperature sensor package 706, when the measured flow and temperature data triggers a response based on the user data stored in memory 716. The microprocessor 712 will add heat energy to the fluid within the fluid conduit system 720 when a value stored in control ROM or flash memory 716 is reached by the sensors 702, 704, and/or 706.
(94) For example, at 32 degrees Fahrenheit water freezes and expands, increasing its volume. Thus, a temperature or temperature range may be chosen at which the microprocessor 712 will add heat energy to the fluid in the fluid conduit system 720 before the water reaches 32 degrees Fahrenheit to prevent it from freezing. If the value is at or below a secondary value stored in control ROM or flash memory 716, such as severe freezing conditions for water, and requires higher heat energy from the heating element, the microprocessor 712 may additionally open the relief valve 724 to evacuate the water in the system and any gas formed in the system due to the addition of the heat energy. The air valve 726 may also be open to allow atmospheric air to enter and any gas to evacuate.
(95) The controller 802 has an internal power supply 821, a microprocessor 814 with memory 816, and interface circuits to control such things as the isolation valve 808, relief valve 809, air valve 846, primary temperature sensor package 806, secondary temperature sensor package 840, external environment temperature sensor 827, and the display unit 804. The display unit 804 utilizes a microcontroller 831 to control the user display panel 830, and external interfaces 832 such as telephone, internet, and alarm.
(96) In addition, the primary temperature sensor package 806 and the secondary temperature sensor package 840 may be utilized to raise the temperature of the fluid to prevent the fluid within the fluid conduit system 810 from freezing. It is contemplated that the primary temperature sensor package 806 and secondary temperature sensor package 840 includes a temperature sensing element and a heating element, as shown in
(97) Referring now to
(98) The system 1100 includes a primary sensor package 1110 including temperature sensing element 1110A (shown in
(99) The system 1100 also includes an external environment temperature sensor 1114 located outside of structure 1101, a first local environment temperature sensor 1116, and a second environment temperature sensor 1118 within structure 1101. The external environment temperature sensor 1114 is configured to measure the temperature outside of the structure 1101. The first local environment temperature sensor 1116 and the second local environment temperature sensor 1118 is configured to measure local temperature within the structure 1101, such as in the basement area 1105 and the attic area 1106. Typically, the basement, attic, and living space are at different temperatures with the basement and the attic generally colder than the living space. As a result, the fluid conduit system 1102 located in the basement area 1105 and in the attic area 1106 are more susceptible to freezing. The external environment temperature sensor 1114, first local environment temperature sensor 1116, and second local environment temperature sensor 1118 is also capable of measuring air temperature, humidity, wind chill, and other measurements. Multiple local environment temperature sensors may be utilized within the structure 1101 to provide a more accurate temperature reading of the structure 1101.
(100) The system 1100 further includes a primary heating element 1120 attached to a portion of the fluid conduit system 1102 located in the basement area 1105 and a secondary heating element 1122 attached to a portion of the fluid conduit system 1102 located in the attic area 1106 of the structure 1101. The primary heating element 1120 and secondary heating element 1122 are removably attached to the fluid conduit system 1102 and may be non-invasively installed on the fluid conduit. The heating elements may be heating blankets, nozzle heaters, or various other heater types. The primary heating element 1120 and secondary heating element 1122 is configured to heat the fluid conduit it is attached to, which in turn heats up the fluid within the fluid conduit system 1102. By placing the primary heating element 1120 and secondary heating element 1122 at the areas of the fluid conduit system 1102 with the coldest temperatures, the heating element may be turned on to prevent the fluid within the conduit from freezing or defrost already frozen fluid within the fluid conduit.
(101) The system 1100 further includes an isolation valve 1136 for interrupting fluid flow into the conduit system 1102, a drainage valve 1134 for releasing fluid in the system, a first relief valve 1130 to allow gas within the system to evacuate the system, and a second relief valve 1132 to allow gas within the system to evacuate the system. The second relief valve 1132 is located at a high point in the system to also allow atmospheric air to enter the system to aid in drainage and release of any negative pressure in the system. It is contemplated that the number of valves are not meant to be limiting and that a user may choose zero or more valves to meet the user's needs.
(102) The system 1100 further includes a control system 1140 with a user interface 1142. The control system 1140 is in communication with the sensor packages, the environment temperature sensors, the heating elements, and the valves. The control system 1140 receives fluid temperature data and fluid flow rate data from the primary sensor package 1110 and the secondary sensor package 1112. The control system 1140 receives environment temperature data from the external environment temperature sensor 1114, the first local environment temperature sensor 1116, and the second environment temperature sensor 1118. The control system 1140 controls the operation of the primary heating element 1120 and the secondary heating element 1122. The control system 1140 also controls the operation of the first relief valve 1130, the second relief valve 1132, the drainage valve 1134, and the isolation valve 1136. The user interface 1142 allows a user to control the operation of the system 1100.
(103) The flow and temperature data from the various sensors are analyzed by the control system 1140 to determine the state of the fluid within the conduit and the temperature of the environment the fluid conduit is exposed to. Based on the temperature and flow of the fluid, the control system 1140 determines whether the fluid in the fluid conduit system 1102 is close to freezing. If the fluid in the conduit system 1102 is close to freezing, the control system turns on the heating elements to heat up the pipes to prevent the fluid within from freezing. The control system 1140 may also turn on the heating elements to heat up the pipes when the external environment temperature or the local environment temperature reaches a predetermined value to prevent the fluid within the conduit from freezing.
(104) For example, at 32 degrees Fahrenheit water freezes and expands, increasing its volume. Thus, a temperature or temperature range may be chosen for the fluid temperature and the environment temperature at which the control system 1140 will add heat energy to the fluid in the fluid conduit system 1102 before the water reaches 32 degrees Fahrenheit to prevent it from freezing. If the value is at or below a secondary value, such as severe freezing conditions for water, and requires higher heat energy from the heating element, the control system 1140 may additionally open the drainage valve 1134 to evacuate the water in the system and any gas formed in the system due to the addition of the heat energy. The relief valves 1130 and 1132 may also be open to allow atmospheric air to enter and any gas to evacuate.
(105) Referring now to
(106) The control system 1140 is configured to operate the primary heating element 1120 and the secondary heating element 1122 upon detection of freezing and near freezing conditions for the fluid within the fluid conduit system 1102. The primary sensor package 1110 and the secondary sensor package 1112 is configured to measure the temperature of the fluid within the fluid conduit system 1102. The control system 1140 may turn on the heating elements 1120 and 1122 to prevent fluid within the fluid conduit system 1102 from freezing when the temperature of the fluid reaches a certain value and if the temperature is at or below a certain value for a predetermined period of time.
(107) The control system 1140 is also configured to operate the primary heating element 1120 and the secondary heating element 1122 upon detection of freezing and near freezing temperatures of the environment in which the fluid conduit system 1102 is located. The external environment temperature sensor 1114 is configured to measure the air temperature outside of the structure 1101. It is also contemplated that the external environment temperature sensor 1114 may also measure wind speed and humidity to determine wind chill. The first local environment temperature sensor 1116 and the second environment temperature sensor 1118 are located in areas in the structure 1101 that are prone to cold spots, such as the basement area 1105 and the attic area 1106. The first local environment temperature sensor 1116 and the second environment temperature sensor 1118 are configured to measure the air temperature of the local area. The data from the external environment temperature 1114, first local environment temperature sensor 1116, and the second environment temperature sensor 1118 is utilized by the control system 1140 to determine the operation of the primary heating element 1120 and the secondary heating element 1122. The control system 1140 may turn on the heating elements 1120 and 1122 to prevent fluid within the fluid conduit system 1102 from freezing when the temperature reaches a certain value, the temperature is at or below a certain value for a predetermined period of time, and the temperature is at or below a certain value and the wind speed is at a certain value.
(108) Referring now to
(109) The system 1200 also includes an external environment temperature sensor 1214 located outside of structure 1101, a first local environment temperature sensor 1216, and a second environment temperature sensor 1218 within structure 1101. The external environment temperature sensor 1214 is configured to measure the temperature outside of the structure 1101. The first local environment temperature sensor 1216 and the second local environment temperature sensor 1218 is configured to measure local temperature within the basement area 1105 and the attic area 1106, respectively. The external environment temperature sensor 1214, first local environment temperature sensor 1216, and second local environment temperature sensor 1218 is also capable of measuring air temperature, humidity, wind chill, and other measurements. Multiple local environment temperature sensors may be utilized within the structure 1101 to provide a more accurate temperature reading of the structure 1101.
(110) The system 1200 further includes a heated recirculation circuit 1220, which includes an exhaust solenoid 1222, a return solenoid 1223, a recirculation conduit 1224, a heating element 1226, and a recirculation pump 1228. The recirculation solenoid 1222 is in communication with the fluid conduit system 1102, near the termination point 1104, and the return solenoid 1223 is in communication with the fluid conduit system 1102 near the inlet 1103. The recirculation conduit 1224 connects between the exhaust solenoid 1222 and the return solenoid 1223 and creates a loop for the fluid conduit system 1102 when the exhaust solenoid 1222 and the return solenoid 1223 are both open. In line with the recirculation conduit 1224 is the heating element 1226 and the recirculation pump 1228. When the heating element 1226 and the recirculation pump 1228 are turned on, the fluid within the fluid conduit system 1102 is heated and circulated by the heated recirculation circuit 1220.
(111) The system 1200 further includes a control system 1230 with a user interface 1240. The control system 1230 is in communication with the sensor packages, the environment temperature sensors, the heating element, the recirculation pump, and the valves. The control system 1230 receives fluid temperature data and fluid flow rate data from the primary sensor package 1210 and the secondary sensor package 1212. The control system 1230 receives environment temperature data from the external environment temperature sensor 1214, the first local environment temperature sensor 1216, and the second environment temperature sensor 1218. The control system 1230 controls the operation of the exhaust solenoid 1222, the return solenoid 1223, the heating element 1226, and the recirculation pump 1228. The user interface 1240 allows a user to control the operation of the system 1200.
(112) The flow and temperature data from the various sensors are analyzed by the control system 1230 to determine the state of the fluid within the conduit and the temperature of the environment the fluid conduit is exposed to. Based on the temperature and flow of the fluid, the control system 1230 determines whether the fluid in the fluid conduit system 1102 is close to freezing. If the fluid in the conduit system 1102 is close to freezing, the control system 1230 turns on the heated recirculation circuit 1220 to heat up the fluid and the pipes to prevent the fluid within from freezing. The control system 1230 may also turn on the heating element to heat up the fluid and pipes when the external environment temperature or the local environment temperature reaches a predetermined value to prevent the fluid within the conduit from freezing.
(113) Referring now to
(114) The control system 1230 is configured to operate the heated recirculation circuit 1220, including the exhaust solenoid 1222, the return solenoid 1223, the heating element 1226, and the recirculation pump 1228, upon detection of freezing and near freezing conditions for the fluid within the fluid conduit system 1102. The control system 1230 may turn on the heated recirculation circuit 1220 to prevent fluid within the fluid conduit system 1102 from freezing when the temperature of the fluid reaches a certain value and if the environment temperature is at or below a certain value for a predetermined period of time. The control system 1230 may turn on the heated recirculation circuit 1220 to prevent fluid within the fluid conduit system 1102 from freezing when the temperature reaches a certain value, the temperature is at or below a certain value for a predetermined period of time, and the temperature is at or below a certain value and the wind speed is at a certain value.
(115) Referring now to
(116) Operation 1150 begins in step 1152 and proceeds to step 1154, which resets all counters, timers, and outputs of the system 1100 to an initial state where a freeze condition is not present and the valves and heating elements are not active. After the system 1100 resets all counters, timers, and outputs, the system 1100 then reads for a freeze condition in step 1155. In step 1155, an operation “Read Freeze Condition” 1300 is performed to determine the freeze condition, which is shown in
(117) Referring now to
(118) Operation 1250 begins in step 1252 and proceeds to step 1254, which resets all counters, timers, and outputs of the system 1200 to an initial state where a freeze condition is not present and the heated recirculation circuit 1220 is not active. After the system 1200 resets all counters, timers, and outputs, the system 1200 then reads for a freeze condition in step 1255, which performs operation “Read Freeze Condition” 1300. After reading for a freeze condition in step 1255, in step 1256 the system 1200 determines if a freeze condition is present. If a freeze condition is not present, the heated recirculation circuit is turned off in step 1258 and loops back to step 1254. If a freeze condition is detected in step 1256, in step 1260 the system 1200 then checks to see if heated recirculation circuit is active due to an earlier loop. If heated recirculation circuit is not active, the heated recirculation circuit is turned on in step 1262 and then loops back to step 1255. If the heated recirculation circuit is active, the system 1200 loops back to step 1255. The operation 1250 for system 1200 allows the heated recirculation circuit to remain active as long as the system 1200 detects a freeze condition. Once a freeze condition is no longer present, the system 1200 deactivates the heated recirculation circuit.
(119) Referring now to
(120) If a freeze condition exists for the first environment temperature sensor (1116 or 1216), the operation outputs a YES for freeze condition in operation 1306. If a freeze condition does not exist for the first environment temperature sensor (1116 or 1216), the second environment temperature sensor (1118 or 1218) is then checked in operation 1304. If a freeze condition exists for the second environment temperature sensor (1118 or 1218), the operation outputs a YES for freeze condition in operation 1306. If a freeze condition does not exist for the second environment temperature sensor (1118 or 1218), the external environment temperature sensor (1114 or 1214) is then checked in operation 1305. If a freeze condition exists for the external environment temperature sensor (1114 or 1214), the operation outputs a YES for freeze condition in operation 1306. If a freeze condition does not exist for the external environment temperature sensor (1114 or 1214), the operation outputs a NO for freeze condition in operation 1307.
(121) Referring now to
(122) If the fluid temperature reading at the primary sensor package (1110 or 1210) is above the first threshold temperature T.sub.PS1, then the fluid temperature reading at the primary sensor package (1110 or 1210) is then compared to the second threshold temperature T.sub.PS2 in step 1313. If the fluid temperature reading at the primary sensor package (1110 or 1210) is above the second threshold temperature T.sub.PS2, then the operation outputs a NO freeze condition in step 1317, the time counter t.sub.PS1 is then reset in step 1318, and then looped back to step 1310. If the fluid temperature reading at the primary sensor package (1110 or 1210) is below or equal to the second threshold temperature T.sub.PS2, then the time counter t.sub.PS1 is compared to the max time at second threshold temperature t.sub.PSmax in step 1314. If t.sub.PS1 is greater than tPSmax, a YES freeze condition is output in step 1315, the time counter t.sub.PS1 is then reset in step 1318, and then looped back to step 1310. if t.sub.PS1 is less than t.sub.PSmax, the time counter t.sub.PS1 is increased in step 1316, then is looped back to step 1312. The second threshold temperature T.sub.PS2 and max time at second threshold temperature t.sub.PSmax provides a factor of safety to prevent possible freezing of fluid due to unexpected wind, dips in temperature, or other unaccounted factors that may affect the temperature of the fluid within the fluid conduit system 1102.
(123) Referring now to
(124) If the fluid temperature reading at the secondary sensor package (1112 or 1212) is above the first threshold temperature T.sub.SS1, then the fluid temperature reading at the secondary sensor package (1112 or 1212) is then compared to the second threshold temperature T.sub.SS2 in step 1323. If the fluid temperature reading at the secondary sensor package (1112 or 1212) is above the second threshold temperature T.sub.SS2, then the operation outputs a NO freeze condition in step 1327, the time counter t.sub.SS1 is then reset in step 1328, and then looped back to step 1320. If the fluid temperature reading at the secondary sensor package (1112 or 1212) is below or equal to the second threshold temperature T.sub.SS2, then the time counter tssi is compared to the max time at second threshold temperature t.sub.SSmax in step 1324. If t.sub.SS1 is greater than t.sub.SSmax, a YES freeze condition is output in step 1325, the time counter t.sub.SS1 is then reset in step 1328, and then looped back to step 1320. If t.sub.SS1 is less than t.sub.SSmax, the time counter t.sub.PS1 is increased in step 1326, then is looped back to step 1322. The second threshold temperature T.sub.SS2 and max time at second threshold temperature t.sub.SSmax provides a factor of safety to prevent possible freezing of fluid due to unexpected wind, dips in temperature, or other unaccounted factors that may affect the temperature of the fluid within the fluid conduit system 1102.
(125) Referring now to
(126) If the fluid temperature reading at the first environment temperature sensor (1116 or 1216) is above the first threshold temperature T.sub.LE11, then the fluid temperature reading at first environment temperature sensor (1116 or 1216) is then compared to the second threshold temperature T.sub.LE12 in step 1333. If the fluid temperature reading at the first environment temperature sensor (1116 or 1216) is above the second threshold temperature T.sub.LE12, then the operation outputs a NO freeze condition in step 1337, the time counter t.sub.LE1 is then reset in step 1338, and then looped back to step 1330. If the fluid temperature reading at the first environment temperature sensor (1116 and 1216) is below or equal to the second threshold temperature T.sub.LE12, then the time counter t.sub.LE1 is compared to the max time at second threshold temperature t.sub.LE1max in step 1334. If t.sub.LE1 is greater than t.sub.LE1max, a YES freeze condition is output in step 1335, the time counter t.sub.LE1 is then reset in step 1338, and then looped back to step 1330. If t.sub.LE1 is less than t.sub.LE1max, the time counter t.sub.LE1 is increased in step 1336, then is looped back to step 1332. The second threshold temperature T.sub.LE12 and max time at second threshold temperature t.sub.LE1max provides a factor of safety to prevent possible freezing of fluid due to unexpected wind, dips in temperature, or other unaccounted factors that may affect the temperature of the fluid within the fluid conduit system 1102.
(127) Referring now to
(128) If the fluid temperature reading at the second environment temperature sensor (1118 and 1218) is above the first threshold temperature T.sub.LE21, then the fluid temperature reading at second environment temperature sensor (1118 or 1218) is then compared to the second threshold temperature T.sub.LE22 in step 1343. If the fluid temperature reading at the second environment temperature sensor (1118 or 1218) is above the second threshold temperature T.sub.LE22, then the operation outputs a NO freeze condition in step 1347, the time counter t.sub.LE2 is then reset in step 1348, and then looped back to step 1340. If the fluid temperature reading at the second environment temperature sensor (1118 and 1218) is below or equal to the second threshold temperature T.sub.LE22, then the time counter t.sub.LE2 is compared to the max time at second threshold temperature t.sub.LE2max in step 1344. If t.sub.LE2 is greater than t.sub.LE2max, a YES freeze condition is output in step 1345, the time counter t.sub.LE2 is then reset in step 1348, and then looped back to step 1340. If t.sub.LE2 is less than t.sub.LE2max, the time counter t.sub.LE2 is increased in step 1346, then is looped back to step 1342. The second threshold temperature T.sub.LE22 and max time at second threshold temperature t.sub.LE2max provides a factor of safety to prevent possible freezing of fluid due to unexpected wind, dips in temperature, or other unaccounted factors that may affect the temperature of the fluid within the fluid conduit system 1102.
(129) Referring now to
(130) If the fluid temperature reading at the external environment temperature sensor (1114 or 1214) is above the second threshold temperature T.sub.ET2, then the operation outputs a NO freeze condition in step 1357, the time counter t.sub.ET1 is then reset in step 1358, and then looped back to step 1350. If the fluid temperature reading at the external environment temperature sensor (1114 and 1214) is below or equal to the second threshold temperature T.sub.ET2, then the time counter t.sub.ET1 is compared to the max time at second threshold temperature t.sub.ETmax in step 1354. If t.sub.ET1 is greater than t.sub.ETmax, a YES freeze condition is output in step 1356, the time counter t.sub.ET1 is then reset in step 1358, and then looped back to step 1350. If t.sub.ET1 is less than t.sub.ETmax, the time counter t.sub.ET1 is increased in step 1355, then is looped back to step 1352. The second threshold temperature T.sub.ET2 and max time at second threshold temperature t.sub.ETmax provides a factor of safety to prevent possible freezing of fluid due to unexpected wind, dips in temperature, or other unaccounted factors that may affect the temperature of the fluid within the fluid conduit system 1102.
(131) Referring now to
(132) The actuator 1402, valve 1404, and leak detector 1410 are in communication with the controller 1401. The actuator 1402 and valve 1404 are mechanically coupled to form an electronically controlled motorized valve. The valve 1404 is a ball valve and is controlled by action of the actuator 1402. Connected to the valve 1404 is the flowbody 1406. The flowbody 1406 is a conduit with a known length 1407 and diameter 1408. The flowbody 1406 is preferably constructed of stainless steel in order to inhibit rust and deposit build-up, which negatively affects the properties of the flowbody 1406. The flowbody 1406 is characterized for use with the leak detector 14010 based on its material properties and dimensions. Attached to the flowbody 1406 is the leak detector 1410 at a known distance 1411 and 1412 from a point on the flowbody 1406. The leak detector 1410 detects a leak by detecting irregular fluid flow within the flowbody 1406 and may be any of the fluid flow sensors described herein. As described above, when a fluid flow rate is exceeded for a period of time, a leak is detected by the system. It is contemplated that Leak Defense System 1400 may have different dimensions for use in particular conduit systems. Each Leak Defense System 1400 is capable of characterizing the valve 1404, flowbody 1406, and leak detector 1410 for use with that particular conduit system before installation.
(133) Referring now to
(134) In operation, the first RTD probe 1414 is actively heated, while the second RTD probe 1416 reports the reference temperature of the water. The first RTD probe 1414 both heats and monitors its own temperature. The second RTD probe 1416 reports the ambient water temperature. In this particular embodiment, the second RTD probe 1416 is not intended to measure the heating effects of the first RTD probe 1414. Utilizing a Wheatstone Bridge circuit with the first RID probe 1414 and the second RTD probe 1416, the controller 1401 is able to set the first RTD probe 1414 to read the second RTD probe 1416 and add extra power (overheat) to the first RTD probe 1414 to maintain a balance condition defined as: ambient and ambient+overheat. The overheat value is determined during the sensor pair characterization process called “temperature compensation.” Because the ambient temperature is always known, the water flow is determined by how much energy the first RTD probe 1414 requires to maintain balance of the circuit. Warm or cold ambient water does not contribute to the flow rate measurement because the ambient condition establishes the reference baseline. Therefore, flow rate is inferred by the system's ability to maintain the overheat temperature.
Another Alternative Embodiment for Geo-Fencing Control
(135) Referring now to
(136) System 904 may be equipped with an antenna 912 which provides wireless communication to other components within the system 900, or to systems or services outside the specific system of the present invention, such as outside service providers (fire, county water services, alarm companies, etc.). Wireless communication may be accomplished using any wireless communication technique or protocol known in the art.
(137) System 900 includes a location based area 914 which is often referred to as a geographical location area, geo-fencing boundary, or geo-fencing area, that determines a range within which the system may be operated or the presence of an occupant may be sensed. For instance, in a preferred embodiment of the present invention, geo-fencing area 914 may have an outer limit one mile from the structure 902 such that the system can switch from AWAY mode to HOME mode when the occupant approaches. In other circumstances, the system may be set such that the geo-fencing area 914 outer limit is minimal, such as when an occupant enters the structure 902 or comes within 100 feet to ensure that there is only minimal time elapsing between the system switching to the HOME mode and the occupant actually entering the property 902.
(138) In this embodiment, a personal electronic device 916A, such as a cellular telephone or other portable electronic device, receives a Global Positioning Satellite (GPS) signal from a GPS Satellite 920 from which the device can determine its location. This GPS location for device 916 is then compared to the geo-fencing boundary 914 and it is determined whether the device 916 is within the geo-fencing boundary, indicating whether the occupant with the device 916 is within the boundary 914. If the occupant is within the boundary, the system enters the HOME mode, and if not, the system will remain in the AWAY mode.
(139) As shown in
(140) As shown in
(141) Also shown in
(142) In a preferred embodiment, property 902 may be equipped with additional RFID readers, such as RFID reader 924A. This allows for the distributed sensing of the presence of an RFID tag 922 within the geo-fencing boundary 914. Using this approach, an occupant need not specifically present the RFID tag 922 to a RFID reader 924; instead, the multiple RFID readers 924, 924A, etc. can sense the presence of the RFID tag 922 anywhere within the geo-fencing boundary maintaining the system in the HOME mode. When an RFID tag is no longer sensed within the geo-fencing boundary 914, the system will switch to the AWAY mode until an RFID tag is again detected within the boundary 914.
(143) The system 900 shown in
(144) An additional occupancy sensor used in the present invention 900 which can assist in the determination of the presence of an occupant is a temporary bypass timer 935 which can be manually set or triggered. This physical timer may have a fixed time period such as a pushbutton that triggers a 30 minute timer, or may be adjustable such as a dial timer that can be set from 0 to 60 minutes. The timer will allow an occupant, such as a service person (housekeeper, gardener, service technician, etc.), to manually switch the system to the HOME mode as needed, and the timer will automatically return to the AWAY mode with no further action needed. This process can be repeated multiple times of the timer period is insufficient for that particular occupant, but absent an affirmative retriggering of the timer, the system will automatically return to the AWAY mode when the timer expires. Additionally, a manual override controller such as a manually activated timer device may be incorporated to provide a manual temporary bypass feature to place the system in the HOME mode.
(145) In addition to occupant-based detection, system 900 also includes point-of-leak detectors 933. In use, point-of-leak detectors are placed adjacent water-using appliances or fixtures, and detect the presence of water, such as when a laundry supply hose bursts, a toilet tank cracks, or other leak events. The input from these detectors 933 are provided to display 304 and utilized to control the valves and associated flow of water to the leak.
(146) Referring now to
(147) Flow chart 1000 begins in step 1002 and proceeds to the configuration of members in step 1004. Specifically, the members that are configured to communicate with a specific system 900 are identified using a portable electronic device 916 (e. g. cellular telephone), or RFID tag 922. Next, the geo-fencing range, or geographical boundary 914, is determined for system 900. This range can be user-determined, and may vary based on the type of property incorporating system 900.
(148) Once each member is configured in step 1004, the location of each member is determined in step 1008. As outlined above, this location determination may be made using GPS data, RFID data, or a combination of such data.
(149) At this point in the flow chart 1000, the location of each member is determined in step 1004, and the geo-fence range has been determined in step 1006. In step 1010, it is determined whether there is any member within the range of the geo-fencing boundary. If no member was determined to be in range in step 1010, step 1011 determines whether a person was detected within the geo-fencing boundary 914, or within the property 902 depending on how the system 900 is configured.
(150) If no person is detected an integrating timer is incremented in step 1024 to avoid false AWAY mode setting by system 900. Specifically, a delay timer is used in flow chart 1000 to require the absence of an occupant for a set period of time before the system switches to an AWAY mode in order to provide for brief instances where the system 900 does not sense the person even though the personhas not left the premises, such as if the personentered a closet, bathroom, or was briefly out-of-range of the occupant sensor. If the time delay is not at its maximum, the delay count is increased in step 1026, and the operation returns along path 1028 to continue to check for the presence of members or occupants.
(151) This process repeats until a member is in range in step 1010, a person is detected in step 1011, or the maximum count has been reached as determined in step 1024. If no member is present, no personis detected, and the timer expires, the system 900 enters the AWAY mode in step 1030. If, on the other hand, a member is in range in step 1010, or a person is detected in step 1011, data path 1012 leads to step 1014 where the system is placed in the HOME mode.
(152) Flow chart 1000 steps 1014 and 1030 both lead to the step 1016 where it is determined whether a flow trip point has been reached. This trip point, as described herein, is user-determined and can be set to various limits throughout the day and week to accommodate scheduled activity and consumptions, such setting higher flow limits during periods of laundry, showers, dishwashing, or garden watering, and at lower flow limits during periods of absence, such as working hours or overnight during sleeping hours. If no flow trip point is reached in step 1016, control returns along line 1018 to the main control path and step 1008. On the other hand, if the flow trip point has been reached in step 1016, the system checks to determine whether the manual temporary bypass has been set in step 1020. If the manual temporary bypass has not been set, the system activates flow lock in step 1022, may notify alarms or other responses based on the configuration of system 900, and ends in step 1024. If the temporary bypass has been set as determined in step 1020, the system returns along path 1018 to step 1008 and resumes as described above.
(153) Referring now to
(154) System 950 includes units 900A, 900B, 900C, 900D, 900E, and 900F. Each of these units may be a system 900 of the present invention as described above, or a system having a combination or one or more features and components of system 900. While each unit 900A-F are shown to be duplicates, it is to be appreciated that the configuration of each unit may differ, and no limitations on the applicability of the present invention to various configurations is intended.
(155) Referring to unit 900A, an optical motion and infrared sensor 934 is combined with an RFID tag 922A and corresponding sensor 924. Also, unit 950A is provided with a manual timer 936. As described above, the optical motion and infrared sensor 934, RFID tag and sensor 922A and 924, and timer 936 provide a unit-specific measure of security and operation of system 900. Also provided is a personal electronic device 916A which corresponds to unit 950A such that when the device 916A is within the geo-fencing boundary (not shown this figure), the system 900 activates to place the system in the HOME mode. Similarly, when personal electronic device 916F leaves the property 952 and no other occupant is detected, the system 900F enters the AWAY mode.
(156) In the event that the system 900 detects a leak or an over-flow condition using flow meter and valve combination 908A, the water flowing from main supply line 954 through branch line 956 can be interrupted using the valve within 908A. In such circumstance, the flow of water to the other unites 900B-F will not be interrupted, with only the water to unit 900A bring interrupted due to the over flow condition. It is to be appreciated that using the same system 900, each of the units 900B-F can be monitored and protected from water damage using the same method and system configuration.
(157) As used herein, RFID tags 922 are identified to communicate with a specific RFID reader 924. As is known in the field of RFID access control, a single RFID tag may be configured to be accepted by more than one RFID reader. For instance, a building maintenance technician may have an RFID tag that is configured to access all RFID readers in property 952, whereas a specific tenant of a single unit will have an RFID tag that is configured to access only that tenant's unit RFID reader.
(158) The system 900 of the present invention can also sense, in a particular configuration, excessive flow to more than one unit, such as the flow through branch line 956 to units 900A, 900C, and 900E. In the event that flow through branch 956 exceeds a predetermined limit and no occupancy is determined in the units it services, flow meter and valve 962 may be activated to shut off water to the entire branch line 956. Similarly, if excessive flow is sensed in branch 958 which services units 900B, 900D, and 900F, flow meter and valve 964 may be activated to shut off flow through branch line 958. Also, in the event that excessive flow is determined to occur in main line 954, flow meter and valve 960 may be activated to shut off supply to the entire building 952.
(159) While
(160) The system 950 may also be scaled up to accommodate large buildings with multiple units over multiple floors to provide a high degree of location specific over-flow detection. Likewise, this system 950 may be scaled larger to provide for building to building level flow monitoring, and even block to block levels of measurement and control depending on the environment of the system and its installation purpose.
(161) While there have been shown what are presently considered to be preferred embodiments of the present invention, it will be apparent to those skilled in the art that various changes and modifications can be made herein without departing from the scope and spirit of the invention.