Claims:1. A method for detecting dry running of a water pump driven by a variable frequency drive motor, the method comprising:
determining ratio ‘k’ of the motor, wherein ‘k’ is ratio between initial voltage V1 and initial frequency f1 while the motor is running at normal speed and load;
determining initial power P1 delivered by the motor;
determining, at an operating frequency f2 at a time of operation, corresponding operating power P2 delivered by the motor by using affinity law P2 =P1/(f1/f2)3 ;
determining operating voltage V2 while keeping ‘k’ constant using formula V2=V1*(f2/f1);
determining operating current I2 at the time of operation using formula I2=P2/(1.732*V2*pf) wherein ‘pf’ is power factor of the motor; and
determining if I2 is greater than a pre-set value IDRYRUN and, upon such determination, detecting that the water pump is running dry.
2. The method of claim 1, wherein the method further includes stopping the motor upon determination that the water pump is running dry.
3. The method of claim 1, wherein the method determines operating current I2 using formula I2=P2/(1.732*V2*pf* ?) wherein ‘?’ is efficiency of the motor.
4. A system to detect dry running of a water pump driven by a variable frequency drive motor, the system configured to:
determine ratio ‘k’ of the motor, wherein ‘k’ is ratio between initial voltage V1 and initial frequency f1 while the motor is running at normal speed and load;
determine initial power P1delivered by the motor;
determine, at an operating frequency f2 at a time of operation, corresponding operating power P2 delivered by the motor by using affinity law P2 =P1/(f1/f2)3 ;
determine operating voltage V2 while keeping ‘k’ constant using formula V2=V1*(f2/f1);
determine operating current I2 at the time of operation using formula I2=P2/(1.732*V2*pf) wherein ‘pf’ is power factor of the motor; and
determine if I2 is greater than a pre-set value IDRYRUN and, upon such determination, detect that the water pump is running dry.
5. The system of claim 4, wherein the system is further configured to stop the motor upon determination that the water pump is running dry.
6. The system of claim 4, wherein the system determines operating current I2 at the time of operation using formula I2=P2/(1.732*V2*pf* ?) wherein ‘?’ is the efficiency of the motor.
, Description:FIELD OF DISCLOSURE
[0001] The present disclosure mainly relates to water pumps. In particular, it relates to protection devices for water pumps to prevent their dry running.

BACKGROUND OF THE DISCLOSURE
[0002] The background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.
[0003] Dry run detection and consequent protection of a water handling pump is one of the most important monitoring and control functions in pump control , as bearings and shaft seal and even the pump motor may be damaged if the pump runs dry, leading to expensive repairs. Almost all pumps employ dry running protection.
[0004] Mostly, dry run protection is provided by flow sensors (that can be pressure switches as well) monitoring the flow of the pump and hence detecting the dry run condition. While several devices exist for flow control in pumps, they all rely on one form or another of water flow sensors. Patent US 7,845,913 B2 for example, uses water flow sensors to control speed of motor driving a pump and so water being delivered by it. Patent “Controller for a motor and a method of controlling the motor
US 8133034 B2” describes a method wherein pressure sensors are deployed on pump inlet side to finally control the motor. Patent “Pump control system and method
US 8540493 B2 ” likewise uses a water flow sensor to sense water pressure and uses this input to control flow of water through the pump. Patent “Pump and pump control circuit apparatus and method US 8641383 B2” includes sensing a pressure in the pump using a water flow sensor and entering a low-flow mode when the sensed pressure is greater than the low flow mode, and patent application “Priming protection US 20070154321 A1” discloses a method and apparatus for sensing the priming status of the pump., using a water flow sensor.
[0005] Flow sensors, however, are costly and generate signals that require expensive filtering and signal conditioning to be used by controller. Further, they are prone to erroneous readings. Hence there is a need in the art for devices that eliminate flow sensors.
[0006] All publications herein are incorporated by reference to the same extent as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.
[0007] In some embodiments, the numbers expressing quantities or dimensions of items, and so forth, used to describe and claim certain embodiments of the invention are to be understood as being modified in some instances by the term “about.” Accordingly, in some embodiments, the numerical parameters set forth in the written description and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by a particular embodiment. In some embodiments, the numerical parameters should be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of some embodiments of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as practicable. The numerical values presented in some embodiments of the invention may contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.
[0008] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[0009] The recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g. “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[00010] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all Markush groups used in the appended claims.

OBJECTS OF THE INVENTION
[00011] Some of the objects of the present disclosure, which at least one embodiment herein satisfies are as listed herein below.
[00012] It is an object of the present disclosure to provide for dry run detection for a water pump.
[00013] It is another object of the present disclosure to provide for protection of a water pump if it starts to run dry.
[00014] It is yet another object of the present disclosure to provide for above detection and protection without using expensive and fault-prone water flow sensors.

SUMMARY OF THE INVENTION
[00015] The present disclosure relates to protection devices for water pumps to prevent their dry running.
[00016] In an aspect, proposed invention discloses a method for detecting dry running of a water pump driven by a variable frequency drive motor, the method comprising: determining ratio ‘k’ of the motor, wherein ‘k’ is ratio between initial voltage V1 and initial frequency f1 while the motor is running at normal speed and load; determining initial power P1 delivered by the motor; determining, at an operating frequency f2 at a time of operation, corresponding operating power P2 delivered by the motor by using affinity law P2 =P1/(f1/f2)3 ; determining operating voltage V2 while keeping ‘k’ constant using formula V2=V1*(f2/f1); determining operating current I2 at the time of operation using formula I2=P2/(1.732*V2*pf) wherein ‘pf’ is power factor of the motor; and determining if I2 is greater than a pre-set value IDRYRUN and, upon such determination, detecting that the water pump is running dry.
[00017] In another aspect, the method can further include stopping the motor upon determination that the water pump is running dry.
[00018] In yet another aspect, the method can determine operating current I2 using formula I2=P2/(1.732*V2*pf* ?) wherein ‘?’ is efficiency of the motor.
[00019] In an aspect, proposed invention discloses a system to detect dry running of a water pump driven by a variable frequency drive motor, the system configured to: determine ratio ‘k’ of the motor, wherein ‘k’ is ratio between initial voltage V1 and initial frequency f1 while the motor is running at normal speed and load; determine initial power P1 delivered by the motor; determine, at an operating frequency f2 at a time of operation, corresponding operating power P2 delivered by the motor by using affinity law P2 =P1/(f1/f2)3 ; determine operating voltage V2 while keeping ‘k’ constant using formula V2=V1*(f2/f1); determine operating current I2 at the time of operation using formula I2=P2/(1.732*V2*pf) wherein ‘pf’ is power factor of the motor; and determine if I2 is greater than a pre-set value IDRYRUN and, upon such determination, detect that the water pump is running dry.
[00020] In another aspect, the system can be further configured to stop the motor upon determination that the water pump is running dry.
[00021] In yet another aspect, the system can determine operating current I2 at the time of operation using formula I2=P2/(1.732*V2*pf* ?) wherein ‘?’ is the efficiency of the motor.
[00022] It can readily be understood that voltage V1 and V2 and frequencies f1 and f2 are those being input to the motor and currents I1 and I2 accordingly being drawn by the motor.
[00023] In an exemplary embodiment, proposed system and method can readily be employed for submersible pumps being operated by variable frequency drive motors.
[00024] Various objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like features.

BRIEF DESCRIPTION OF DRAWINGS
[00025] The accompanying drawings are included to provide a further understanding of the present disclosure, and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure. The diagrams are for illustration only, which thus is not a limitation of the present disclosure, and wherein:
[00026] FIG. 1 illustrates most usual form of dry run pump protection presently employed (prior art).
[00027] FIG. 2 illustrates a block diagram of pump driven by a motor that in turn gets power input from both grid as well as solar (PV Panel), in accordance with an exemplary embodiment of the present disclosure.
[00028] FIG. 3 illustrates by means of a flowchart the algorithm for sensor less dry run protection for a variable frequency drive motor driving a pump, in accordance with an exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION
[00029] The following is a detailed description of embodiments of the disclosure depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the disclosure. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure as defined by the appended claims.
[00030] In the following description, numerous specific details are set forth in order to provide a thorough understanding of embodiments of the present invention. It will be apparent to one skilled in the art that embodiments of the present invention may be practiced without some of these specific details.
[00031] Embodiments of the present invention include various steps, which will be described below. The steps may be performed by hardware components or may be embodied in machine-executable instructions, which may be used to cause a general-purpose or special-purpose processor programmed with the instructions to perform the steps. Alternatively, steps may be performed by a combination of hardware, software, and firmware and/or by human operators.
[00032] Various methods described herein may be practiced by combining one or more machine-readable storage media containing the code according to the present invention with appropriate standard computer hardware to execute the code contained therein. An apparatus for practicing various embodiments of the present invention may involve one or more computers (or one or more processors within a single computer) and storage systems containing or having network access to computer program(s) coded in accordance with various methods described herein, and the method steps of the invention could be accomplished by modules, routines, subroutines, or subparts of a computer program product.
[00033] If the specification states a component or feature “may”, “can”, “could”, or “might” be included or have a characteristic, that particular component or feature is not required to be included or have the characteristic.
[00034] As used in the description herein and throughout the claims that follow, the meaning of “a,” “an,” and “the” includes plural reference unless the context clearly dictates otherwise. Also, as used in the description herein, the meaning of “in” includes “in” and “on” unless the context clearly dictates otherwise.
[00035] Exemplary embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. These exemplary embodiments are provided only for illustrative purposes and so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those of ordinary skill in the art. The invention disclosed may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Various modifications will be readily apparent to persons skilled in the art. The general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Moreover, all statements herein reciting embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure). Also, the terminology and phraseology used is for the purpose of describing exemplary embodiments and should not be considered limiting. Thus, the present invention is to be accorded the widest scope encompassing numerous alternatives, modifications and equivalents consistent with the principles and features disclosed. For purpose of clarity, details relating to technical material that is known in the technical fields related to the invention have not been described in detail so as not to unnecessarily obscure the present invention.
[00036] Thus, for example, it will be appreciated by those of ordinary skill in the art that the diagrams, schematics, illustrations, and the like represent conceptual views or processes illustrating systems and methods embodying this invention. The functions of the various elements shown in the figures may be provided through the use of dedicated hardware as well as hardware capable of executing associated software. Similarly, any switches shown in the figures are conceptual only. Their function may be carried out through the operation of program logic, through dedicated logic, through the interaction of program control and dedicated logic, or even manually, the particular technique being selectable by the entity implementing this invention. Those of ordinary skill in the art further understand that the exemplary hardware, software, processes, methods, and/or operating systems described herein are for illustrative purposes and, thus, are not intended to be limited to any particular named element.
[00037] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.
[00038] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.
[00039] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
[00040] The present disclosure relates to protection devices for water pumps to prevent their dry running.
[00041] In an aspect, proposed invention discloses a method for detecting dry running of a water pump driven by a variable frequency drive motor, the method comprising: determining ratio ‘k’ of the motor, wherein ‘k’ is ratio between initial voltage V1 and initial frequency f1 while the motor is running at normal speed and load; determining initial power P1 delivered by the motor; determining, at an operating frequency f2 at a time of operation, corresponding operating power P2 delivered by the motor by using affinity law P2 =P1/(f1/f2)3 ; determining operating voltage V2 while keeping ‘k’ constant using formula V2=V1*(f2/f1); determining operating current I2 at the time of operation using formula I2=P2/(1.732*V2*pf) wherein ‘pf’ is power factor of the motor; and determining if I2 is greater than a pre-set value IDRYRUN and, upon such determination, detecting that the water pump is running dry.
[00042] In another aspect, the method can further include stopping the motor upon determination that the water pump is running dry.
[00043] In yet another aspect, the method can determine operating current I2 using formula I2=P2/(1.732*V2*pf* ?) wherein ‘?’ is efficiency of the motor.
[00044] In an aspect, proposed invention discloses a system to detect dry running of a water pump driven by a variable frequency drive motor, the system configured to: determine ratio ‘k’ of the motor, wherein ‘k’ is ratio between initial voltage V1 and initial frequency f1 while the motor is running at normal speed and load; determine initial power P1 delivered by the motor; determine, at an operating frequency f2 at a time of operation, corresponding operating power P2 delivered by the motor by using affinity law P2 =P1/(f1/f2)3 ; determine operating voltage V2 while keeping ‘k’ constant using formula V2=V1*(f2/f1); determine operating current I2 at the time of operation using formula I2=P2/(1.732*V2*pf) wherein ‘pf’ is power factor of the motor; and determine if I2 is greater than a pre-set value IDRYRUN and, upon such determination, detect that the water pump is running dry.
[00045] In another aspect, the system can be further configured to stop the motor upon determination that the water pump is running dry.
[00046] In yet another aspect, the system can determine operating current I2 at the time of operation using formula I2=P2/(1.732*V2*pf* ?) wherein ‘?’ is the efficiency of the motor.
[00047] It can readily be understood that voltage V1 and V2 and frequencies f1 and f2 are those being input to the motor and currents I1 and I2 accordingly being drawn by the motor.
[00048] In an exemplary embodiment, proposed system and method can readily be employed for submersible pumps being operated by variable frequency drive motors.
[00049] Various objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like features.
[00050] In an aspect, proposed invention utilizes constant V/F (volts hertz) control method for speed control of variable frequency drive motor (that is an AC induction motor) being used to drive the pump. The purpose of the volts hertz control scheme is to maintain the air gap flux of the motor constant in order to achieve higher run-time efficiency. The magnitude of stator flux is proportional to the ratio of stator voltage and frequency. If this ratio is kept constant the stator flux remains constant and so motor torque will only depends upon slip frequency.
[00051] If, in an induction motor, an attempt is made to reduce the supply frequency at the rated supply voltage, the air gap flux will tend to saturate, causing excessive stator current and distortion of flux wave. Therefore, the region below the base or rated frequency should be accompanied by the proportional reduction of stator voltage so as to maintain the air gap flux constant. By varying the voltage and frequency the torque and speed can be varied. The torque can be maintained constant, while varying the speed.
[00052] A V/F control system has several advantages. The motor usually has low slip characteristics (i.e. low rotor resistance), giving high efficiency. Further, in spite of the low inherent starting torque for base frequency operation, it can always be started at maximum torque. High in-rush starting current can be avoided thereby reducing stress and improving life of the motor. Almost constant torque can be maintained over a wide speed range.
[00053] FIG. 1 illustrates most usual form of dry run pump protection presently employed (prior art).
[00054] As illustrated, motor 104 of a water pump 106 (a submersible pump, for example) is controlled by a controller 102 that controls supply of power from grid 110 to the motor 104. The pump 106 is operatively connected to a flow sensor 108 that provides signals to controller 102. In case the pump 106 is running dry, flow sensor 108 provides appropriate signal to the controller 102 based upon which the controller 102 stops power supply from the grid 110 to the motor 104, thereby stopping the motor 104 and so the pump 106.
[00055] As can be readily appreciated, present system requires a flow sensor with its consequent disadvantages as elaborated above.
[00056] FIG. 2 illustrates a block diagram of pump driven by a motor that in turn gets power input from both grid as well as solar (PV Panel), in accordance with an exemplary embodiment of the present disclosure.
[00057] In an aspect, drive system 210 of the pump can include a three phase rectifier 204, a three phase inverter 202 and a controller 206. Rectifier 204 can get power from grid 212 and send it to inverter 202. Inverter 202 can also get power from Photo Voltaic Panels 220. Inverter 202 can in turn supply AC power to variable frequency drive motor 214 (that is an induction motor) that can in turn drive pump 218. Controller 206 can be operatively connected to inverter 202 and can get inputs from current sensors 216a and 216b that can detect current at output of inverter 202 and can send signals dependent upon such current to controller 206. In turn, controller 206 can provide protection, monitoring and controlling features for pump 218 through its control of motor 214.
[00058] In another aspect, proposed invention uses variable frequency drive motor (214) for energy saving in pumps as compared to throttle controlled pumps wherein pump operates at a fixed speed and a throttle valve is used to control its flow rate.
[00059] In yet another aspect, proposed invention determines operating current at an operating speed using a novel algorithm based on affinity law and V/F control method, as elaborated hereunder. The operating current so found can be compared with a pre-set value and if the operating current exceeds this pre-set value, controller 206 can stop power to the motor 214 and so protect pump 218 from dry run fault. The pre-set value can be provided by a user of the proposed system.
[00060] FIG. 3 illustrates novel algorithm proposed for sensor less dry run protection for a variable frequency drive motor driving a pump, in accordance with an exemplary embodiment of the present disclosure.
[00061] As elaborated above, proposed invention relies upon speed control of pump wherein the speed control of pump is performed keeping flux of the motor driving the pump constant in order to get maximum torque from the motor. For an induction motor used herein, flux can be kept constant by keeping the ratio of Voltage (V) to operating frequency F as constant, i.e.by keeping V/F constant at a value, say ‘k’.
[00062] In another aspect, once a motor start command is given, the system starts the motor and continuously checks further requirements of power and accordingly, current.
[00063] In yet another aspect, input power required by the pump at various pump loads can be calculated according to affinity laws as per below equations:-
Q1/Q2 =N1/N2…. (1)
P1/P2 = (N1/N2)3… (2)
H1/H2=(N1/N2)2…. (3)
Wherein Q is the water discharge, P is the power delivered by the pump, H is the head at which water is pump and N is the shaft speed of the pump.
[00064] In case the pump is being driven by an induction motor, as in present case, shaft speed is directly proportional to input frequency f being supplied to the induction motor. Hence, it can be understood from above that flow is proportional to frequency, motor power is proportional to cube of frequency and head (or pressure) is proportional to square of frequency and the equations can also be expressed as :
Q1/Q2 =f1/f2…. (4)
P1/P2 = (f1/f2)3… (5)
H1/H2=(f1/f2)2…. (6)
[00065] As elaborated in the FIG.3.the motor power P2 at any point of operation of the motor can be calculated using the equation (5) i.e. power and frequency relation. Based upon this, operating current being drawn by the motor at its present operating frequency while flux is being maintained constant per V/F control method elaborated above, can be calculated. In case this operating current is higher than a pre-set value (that can be termed IDRYRUN), proposed system can determine that the pump is running dry and can take further steps to stop the motor and hence protect the pump.
[00066] In an aspect the method can include, at step 302, determining whether pump motor is running and if not, starting the motor.
[00067] In another aspect the method can include, at step 304, operating the motor at normal load with initial frequency f1 and initial voltage V1.
[00068] In yet another aspect, the method can include, at step 306, applying V/F control and determining constant ‘k’=V1/f1 for the motor. In an exemplary embodiment, initial frequency being 50 Hz and Voltage V being 420 volts, ‘k’ can be calculated as 8.4, as illustrated.
[00069] In yet another aspect the method can include, at step 308, determining initial power P1 being delivered by the motor. In an exemplary embodiment, P1 can be rated power of the motor when it is drawing full current and operating at normal frequency, voltage and load.
[00070] As the motor operates, proposed system using V/F control method elaborated above can vary its operating frequency f2 to vary its speed per flow requirements. Since ‘k’ is being kept constant by V/F control method, operating voltage V2 at any operating frequency can be determined as V2= V1*(f2/f1).
[00071] In an aspect the method can include, at step 310, calculating power P2 being delivered by the motor at any operating frequency f2 using affinity laws equations elaborated above, since power delivered by the motor is being taken by the pump it is connected to. As illustrated, power P2 =P1/(f1/f2)3 .
[00072] In another aspect, the method can include, at step 312, determining operating voltage V2 by using formula V2=V1*(f2/f1) since ‘k’ has to remain constant due to V/F control being applied to control the motor.
[00073] In another aspect, the method can include, at step 314, calculating motor operating current I2 using the formula:
I2=P2/(1.732*V2*pf)
wherein pf is power factor of the motor. In this fashion, method of the proposed system can enable determination of current being drawn by the motor at any operating frequency.
[00074] In yet another aspect the method can include, at step 316, determining if I2 is greater than a pre-set value (illustrated as IDRYRUN) and if not, repeating the method from step 310, that is continuously monitoring operating frequency f2 of the pump and finally calculating I2.
[00075] In an exemplary embodiment, value of IDRYRUN can be set by the user depending upon type and construction of the pump. This value can be provided to proposed system using an appropriately configured Human Machine Interface (HMI).
[00076] In an aspect the method can include, at step 318, ramping down the motor and switching it off by stopping gate pulse to inverter supplying power to the motor (as elaborated in FIG. 2) and so enable dry run protection, if I2 is greater than IDRYRUN.
[00077] As used herein, and unless the context dictates otherwise, the term “coupled to” is intended to include both direct coupling (in which two elements that are coupled to each other or in contact each other) and indirect coupling (in which at least one additional element is located between the two elements). Therefore, the terms “coupled to” and “coupled with” are used synonymously. Within the context of this document terms “coupled to” and “coupled with” are also used euphemistically to mean “communicatively coupled with” over a network, where two or more devices are able to exchange data with each other over the network, possibly via one or more intermediary device.
[00078] Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C ….and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.
[00079] While some embodiments of the present disclosure have been illustrated and described, those are completely exemplary in nature. The disclosure is not limited to the embodiments as elaborated herein only and it would be apparent to those skilled in the art that numerous modifications besides those already described are possible without departing from the inventive concepts herein. All such modifications, changes, variations, substitutions, and equivalents are completely within the scope of the present disclosure. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims.

ADVANTAGES OF THE INVENTION
[00080] The present disclosure provides for dry run detection for a water pump.
[00081] The present disclosure provides for protection of a water pump if it starts to run dry.
[00082] The present disclosure provides for above detection and protection without using expensive and fault-prone water flow sensors.