rr
`(12) INTERNATTONAL APP‘IJCAT‘TON PUBLISHER UNBER THE PATENT COOPERATION TREATY (PCT)
`(19) World intellectual Pl‘tlpel’iy
`«C
`Organizatinn
`litterriational Bureau
`
`(43) International Publicatlen Date
`24 September ZillS (24.69.2lll5)
`
`WTPG l PCT
`
`Willi
`
`{10) international Publication Number
`
`‘WO lel S/l 39769 All
`
`(51)
`
`international Patent Classification:
`£038 7/0!) (2006M)
`6011913148 (2006,0l)
`E183 7/!)7(2006ill)
`{9015/13/28 (NORM)-
`F172} 5/02 (2006.0 l)
`G01F15/(i75 (2006.0 1)
`
`(83)
`
`(21)
`
`Tntematinnal Applicatlen Number:
`
`PCT/EPZOM/OSSCSAS
`
`(22)
`
`International Filing Date:
`
`20 March 20M (20.03.2014)
`
`(25)
`
`(25')
`
`(71}
`
`(72)
`
`(74‘)
`
`Filing Language:
`
`Publication Language;
`
`English
`
`English
`
`Applicant: HUSQVARNA All
`’l s-smsz Huskyarna {SE}.
`
`[SE/SE};
`
`Drottrtinggatan
`
`(84)
`
`7. 89079
`Johannes; Briihlsteige
`inventors; GUNGL,
`UlmuEggingen (DE). SOUR, Harlan; Eisenlauerstrasse
`TL 893 l2 Gunzhurg (DE).
`
`Agent: FENKELE, Ralf; c/o GARDENA Manufacturing
`Gmhll, Hans-Lorenser—Strasse 40, 89079 Ulrn (DE).
`
`Designated States (unless otherwise indicated, far away
`kind 4;! nationalpmfecfivn available): AE, AG, AL, AM,
`A0, AT, AU, AZ, BA, BB, BG, BH, 8N, BR, BW, BY,
`BZ, CA, CH CL, CN, CO, CR, CU, CZ, DE, DK, DM,
`DO, DZ, EC, EE, EG, ES El, GB, GD, GE, GH, GM, GT.
`RN, HR, HU, ll), 1L, TN, 1R, l5, TR, KE, KG, KN, KP, KR,
`KZ, LA, LC, LK, LR, LS, LT, LU, LY, MA, NE), NE,
`MG, lvTK, MN, MW, l‘vTX, MY, MZ, NA, NS, NT, NO, NZ,
`OM, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW. SA.
`SC, SD, SE, SG, SK, SL, SM, ST, SV, SY, Tll, Tl, TM,
`TN, TR, TT, T_., UA, UG, US, UZ, VC, VN, ZA, ZM,
`ZW.
`
`Designated States (unless otherwise indicated, far away
`kind if regional protection available): ARTPO (BW, GH,
`GM, RE, LR. LS, MW, MZ, NA, RW, SD, SL, SZ, TZ,
`UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, Tl,
`
`TM European (AL, AT, BE, BG, CH, CY, CZ, DE, DK,
`
`EE, ES, Fl, FR, GB, GR, HR, HU, l'j lS, FT, LT, LU, LV,
`MC, MK. MT, NL, NO, PL, PT, RO, RS, SE, SI, SK, SM.
`TR), OAPI (BF, El, CF, CG, CI, CM, GA. GN, GQ, GW,
`KM, l‘th.., MR NE, SN, TD, TG).
`
`(5-1)
`
`Title: DRIPPING ALERT EUN CTlON
`
`
`
`
`
`‘ wait tor 2 min
`
`
`
`[ti'omimted (m nettpatge}
`
`(57) Abstract: A water distribution sy steni (10) may include
`a pump assembly (30) and a controller (60) that controls op—
`eration of the pump assembly. The controller (60) may be
`configured to control cycling of the pump assembly on and
`off based on pressure and flew cenditicns detected in the
`systeni, track a first period of time, count 3 number of tin/oft
`cycles of the pump assembly, determine whether to make a
`state change based (in the number of cit/till” cycles and the
`first period of time, and, in response to determining to make
`the state change, set a timer ccnfigui‘ed tn ccunt a second
`perictl cftinie that is longer than the first period of time and
`counting tan/off cycles (luring discrete periods oftirne for the
`
`second period of time to initiate a fault resspcnsse in response
`to a predetermined number of tin/eff cycles beingr detected
`during each discrete period cl‘tiine during the second peried
`of time or if the second pericd cl‘tinie has lapsed, or initiate
`a recovery from the state change in iespcnse to the predeter—
`rnmed number of cry/off cycles not being detected during at
`least one discrete period ct‘tiine dining the second period of
`time.
`
`

`

`WG 2615/139760 AE liimlllfixillfixflallHamillnlflifllillElIIEEEIHEEIEIEIIEEEEEEEWEEEIEIEIIEEHEflllflii
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`Published:
`
`-----
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`with international march repart (Art. 21' (3))
`
`

`

`W'O 2hl5/13976ll
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`PC’l‘iEPZUM/llfifihdh
`
`DRlPPlNG ALERT FUNCl‘lON
`
`TECHNICAL FlELD
`
`{tltlttl}
`
`Example embodiments generally relate to water supply equipment and, more
`
`particularly relate to a system for accurately determining when water supply equipment is
`
`experiencing a leak.
`
`BA ’JKGROUND
`
`{CHEM}
`
`Gardening> and various other household tasks require apressurized water supply in
`
`order to deliver water to various consumers of water (tie.a devices that apply or use the
`
`water). Some people receive water from puhlic sources that are pressurized to supply water
`
`to their homes. However. others utilize thy choice or necessity) alternative water supplies
`
`and therefore need a mechanism to pressurize the t rater for distribution.
`
`{8903}
`
`Washing machines, sprinkler systems, hoses, water applicators, water taps (or
`
`spigots) and the like may all he consumers of water within ahome or business. As such,
`
`these devices may he components of a system to which water can be pumped under the
`
`supervision of a controller that can control pimips and/or valves of the system to provide
`
`pressure in the supply line for any of the devices listed above to dispense or use. Water for
`
`such a system may be sourced from a puhlic water supply, from a well, or from a, cistern or
`
`other water sources that may he specific to a home or business.
`
`{@904}
`
`ln son e cases, the system may employ an electronic pressure pump that interfaces
`
`with a pressure sensor and/or llow sensor in the system to control switching, the pump on and
`
`off.
`
`lf no water flow is detected at an outlet line of the pump (or if the pressure increases to
`
`an upper threshold limit), the pump may assume that there is no active consumer (eg, all
`
`water dispensing equipment is off) and stop the motor of the pump. As soon as the pressure
`
`drops below a certain threshold value (eg. due to opening a water dispenser), the pump may
`
`he started to pressurize the system to serve the consumer. Thus, the flow sensor and pressure
`
`sensor may work together to start and stop the pump.
`
`{titltFS}
`
`lf a lealc occurs in the system. the pressure drop maybe detected and the pump
`
`may start.
`
`ln some cases, as the pressure increases in the line Without significant water flow,
`
`the pump may stop and the system may continuously cycle between turning the pump on and
`
`off in response to the lealr situation. Accordingly, it may he desirable to provide some form
`
`ofleak detection to stop the pump from falling into the cycle described alcove.
`
`.17..
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`

`

`W0 2915/139760
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`FCTYEEQlll-l/llifibflid
`
`Billlili‘ SLlhéllt/lAR‘i" OF SOME EXAMPLES
`
`[0006}
`
`Some example embodiments may therefore provide a controller that may be
`
`configured to detect leakage scenarios and stop pump operation accordingly. However, some
`
`example embodiments may further be enabled to detect situations where modern water
`
`consumers might provide confusing indications to the controller that might mistakenly be
`
`identified as lealt situations.
`
`[0007}
`
`A water distribution system may include apump assembly and a controller that
`
`controls operation of the pump assembly. The controller may be configured to control
`
`cycling, of the pump assembly on and off based on pressure and flow conditions detected in
`
`the system, track a first period of time, count a number of on/off cycles of the pump
`
`assembly, determine whether to make a state change based on the number of oil/ell cycles
`
`and the first period of time, and, in response to determining to nialie the state change, set a
`
`timer configured to count a second period of time that is longer than the lirst period ot‘time
`
`and counting (in/off cycles during discrete periods of time for the second period of time to
`
`initiate a fault response in response to a predetermined number of on/ol‘l‘ cycles being
`
`detected during each discrete period of time during the second period of time or if the second
`
`period of time has lapsed, or initiate arecoyery froin the state change in response to the
`
`predetermined num her of on/off cycles not being detected during at least one discrete period
`
`of time during the second period of time.
`
`[0008}
`
`ln another example embodiment, a method of controlling a water distribution
`
`system that includes a pump assembly and a controller that controls operation of the pump
`
`assembly is provided, The method, may include controlling cycling of the puni p assembly on
`
`and ell based on pressure and llow conditions detected in the system, traclting a first period
`
`of time, counting a number of on/off cycles of the pump assembly, and determining whether
`
`to nialie a state change based on the number of on/oll cycles and the first period of time The
`
`method may further include, in response to determining to make the state change, setting a
`
`timer configured to count a second period of time that is longer than the first period of time
`
`and counting on/off cycles during discrete periods of time for the second period of time in
`
`order to a) initiate afault response in response to a, predetermined number of on/off cycles
`
`being detected during each discrete period of time during the second period. of time or if the
`
`second, period ol‘time has lapsed, or b) initiate a recovery from the state change in response to
`
`the predetermined number of on/ol'f cycles not being detected during; at least one discrete
`
`period oftime during the second period oftime.
`
`J),
`
`

`

`W0 2915/139760
`
`FC'lYEEQlJld/llifibfttb
`
`BRIEF DESCRlPTlClN OF THE SEVERAL VIEWS OF THE DRAWlNGCS)
`
`{lllltlll}
`
`Having thus described the invention in general terms, reference will now be made
`
`to the accompanying drawings, which are not necessarily drawn to scale, and wherein:
`
`{lllllll}
`
`Flt}.
`
`l illustrates a blocl; diagram of a water distribution system in accordance
`
`with an example embodiment;
`
`{Gilli}
`
`FlG. 2 illustrates a timing diagram showing a number of cycles of the pump
`
`assembly between on and off states and the timing of operations according to first and second
`
`variations of a, method for leakage detection in accordance with an example embodiment;
`
`{($12}
`
`FlG. 3 illustrates a, timing diagram showing a number of cycles of the pump
`
`assembly between on and off states and the timing of operations according to third and fourth
`
`variations ofa method. for leakage detection in accordance with an example embodiment;
`
`{8913}
`
`FlG. 4 illustrates a block diagram of an algorithm for lealrage detection in
`
`accordance with an example embodiment;
`
`{tibial}
`
`FlG. 5 illustrates a block diagram of an alternative algorithm for leahage detection
`
`in accordance with an example embodiment;
`
`{lllllS}
`
`FlG. 6 illustrates a blocl< diagram of another alternative algorithm for leakage
`
`detection in accordance with an example embodiment;
`
`timid}
`
`FlG. 7 illustrates a, timing diagram showing a number of cycles of the pump
`
`assembly between on and off states and the timing of operations according to algorithms
`
`similar to those of ElGS. 4 and. 5 for leakage detection in accordance with an example
`
`embodiment;
`
`{tllll'l’}
`
`FlG. 8 illustrates a tinting diagram showing; a number of cycles of the pump
`
`assembly between on and off states and the timing of operations according to an algorithm
`
`similar to that ofli‘lG. 6 for leal~:age detection in accordance with an example embodiment;
`
`and
`
`{Gold}
`
`FlG. 9 illustrates a blocl: diagram for a method of lealzage detection in accordance
`
`with an example embodiment.
`
`DETAILED DESCRlFTlON
`
`{@919}
`
`Some example embodiments now will be described more fully hereinafter with
`
`reference to the accompanying drawings in which some, but not all example embodiments
`
`are shown.
`
`Indeed, the examples described. and pictured herein should not be construed as
`
`being limiting as to the scope, applicability or configuration oftlie present disclosure.
`
`-3,
`
`

`

`WC 2915/ l3976lt
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`FC'.l‘/EE’2lJl-’l/ll55648
`
`Rather, these esample embodiments are provided so that this disclosure will satisfy
`
`applicable legal
`
`'equirenients. Like reference :numerals refer to like elements throughout.
`
`Furthermore, as used herein, the term "or” is to be interpreted as a logical operator that results
`
`in true whenever one or more of its operands are true. As used herein, operable coupling
`
`should be understood to relate to direct or indirect connection that, in either case, enables
`
`functional interconnection of components that are operably coupled to each other. As used
`
`herein, the term cycle should be understood as an on/ol‘f cycle that can be measured from an
`
`on event to a next on event, from an off event to a next off event, from an off event to a next
`
`on event, or even from an on event to a next off event.
`
`{tilthl}
`
`Some example embodiments described herein provide an improved design for a
`
`controller and an algorithm for execution by the controller to detect leakage in water supply
`
`system. Referring to the situation described. above, one approach to perloiming leakage
`
`detection may be to monitor the switching operation of the pump to determine whether the
`
`switching of the pump appears to follow a pattern that may he expected if there is a leak.
`
`This may be done a couple ol‘dillerent ways. Generally speaking, however, a controller may
`
`monitor pump operation to determine a number of switching on/ol‘t" operations and a time
`
`period. The comparison of the number of switching on/of’f operations, n, to apredetermine
`
`threshold period of time tl, maybe used to determine whether a leakage situation can be
`
`identified by the controller and the controller may stop pump operations and/or display a
`
`message to the operator (eg, an error message) when leakage is detected.
`
`{99le
`
`FlG.
`
`l illustrates an example system it) in which an example embodiment may be
`
`employed. The system to may include awater source 20, a pump assembly 30, a distribution
`
`system 4-0 and a plurality of consumers St). The pump assembly 30 may be selectively
`
`operated by a controller 60 that interfaces with a pressure sensor 70 and/or a ilow sensor 80.
`
`The pressure sensor 7 O and llow sensor 80 may monitor pressure and flow conditions,
`
`respectively, in the distribution system 40, which may include an outlet of the pump assembly
`
`30 and all distribution piping, headers, hoses, valves or other distribution hardware that
`
`connects the pump assembly 30 to the consumers 50. Accordingly, the pressure sensor '70
`
`and flow sensor 80 could be part of the pump assembly 30, part of the distribution system 40
`
`or separate from such components, but in communication therewith to monitor conditions
`
`therein. The consumers 50 may be any water application devices (eg, sprinkler heads, water
`
`taps, etc) or other users of water within the system to.
`
`{@022}
`
`The pump assembly 30 may include a pump and motor. The motor may be
`
`powered selectively based on control implemented by the controller and when the motor
`
`-4,
`
`

`

`W0 2915/139760
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`PCP/EP2lJ1-l/ll55648
`
`operates, the pump :may pressurize the distribution system 40 responsive to drawing water
`
`from the water source 20. As mentioned above, the water source 2t) may be a public wate
`
`supply, a well, a cistern or other water sources that may be specific to a home or business.
`
`The controller 60 may monitor pressure and flow in the distribution system 40 using the
`
`pressure sensor 70 and the ilow sensor 80 to control the pump assembly 30 as described
`
`above.
`
`ln this regard, when llow is detected and pressure drops, the controller 60 may start
`
`the pump assembly 30 to raise the system pressure and maintain the pressure to support the
`
`llow. When flow is stopped, the pump assembly 30 may be stopped. This maybe detected
`
`as an on/off cycle, and may continue as needed to supply the consumers 50 on a continuous
`
`or intermittent hasis.
`
`{£3923}
`
`lf a leak occurs in the system it), the pressure drop maybe detected and the pump
`
`assembly 30 may be started, but increase to the cutotl' pressure relatively quickly and flow
`
`stops so that the pump is stopped. Meanwhile, shortly after shutdown of the pump assembly
`
`30, the pressure may again drop with flow going out the leali, so the pump assembly 30 may
`
`be triggered by the controller 60 to start again. Thus, on/ofl cycles may occur in relatively
`
`quick succession. To mitigate this situation, it may be desirable to configure the controller 60
`
`to detect the leakage based on considering the number of on/ol‘l‘ cycles and time,
`
`{£3924}
`
`There may be a number of variations on how the controller 60 uses the time
`
`information and pump cit/off cycles to determine a leak. For example, ccording to a first
`
`variation, the controller 60 may be configured to count the num her of on/off cycles until a
`
`predetermined number, n, is reached.
`
`‘When the predetermined number ol‘cycles is reached
`
`tie, when the num her of cycles = n), the time, t, that it has taken to reach the predetermined
`
`number of cycles may be compared to the predetermined threshold period of time, tl.
`
`lft is
`
`greater than tl, then controller 60 may be configured to assume that there is no leahage.
`
`l-loweyer, if t is less than tl,
`
`then the controller 60 may he configured to assume that there is
`
`a leak.
`
`{6&5}
`
`According to a second variation, a series of counting operations may he performed
`
`in parallel on a rolling basis by counters. Counters may be separate components in
`
`communication with the controller 60, or may be programmed functions capable of execution
`
`by the controller 60. Each time a new on/off cycle is detected, one of a plurality of counters
`
`(max. of) will be started. With each of the counters, the elapsed. time, t, for the number of
`
`cycles to reach the predetermined number of cycles, n, is measured.
`
`If any of the counters
`
`reaches the predetermined number of cycles, n, in a time, t, that is less than tl, then a leak is
`
`

`

`W0 ZlBlS/l3976ll
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`FC',l‘/EE’2lJl-l/ll55648
`
`detected by the controller 60. However, il‘t is greater than tl for each counter, no leakage is
`
`detected.
`
`{inns}
`
`As shown in Flt}.
`
`the controller 60 may include one or more instances of a
`
`processor 62 and memory 64, and in some cases may also include auser‘ interface 66. The
`
`processor 62 and memory 64 may define processing circuitry that may be configurable to
`
`perform various functions or tasks as described herein. As such, the control unit 60 may be
`
`configured to perform data processing, control function execution and/or other processing
`
`and management services according to an example embodiment of the present invention.
`
`in
`
`some embodiments, the controller 60 may be embodied as a chip or chip set.
`
`ln other words,
`
`the controller 60 may comprise one or more physical packages (eg, chips) including
`
`materials, components and/or wires on a structural assembly (eg, abaseboard). The
`
`structural assembly may provide physical strength, conservation of size, and/or limitation of
`
`electrical interaction for component circuitry included thereon. The controller 60 may
`
`therefore, in some cases, be configured to implement an embodiment of the present invention
`'1
`on a single chip or as a single "sy stern on a chip.’ As such, in some cases, a chip or chipset’
`
`may constitute means for performing one or more operations for providing the functionalities
`
`described herein.
`
`{£3927
`
`The user interface 66, if employed, may be in communication with the processing
`
`circuitry to receive an indication ofa user input at the user interface 66 and/or to provide an
`
`audible, visual, tactile or other output to the user. As such, the user interface 66 may include,
`
`for example, a display, one or :more levers, switches, buttons or keys (eg, function buttons),
`
`and/or other input/output mechanisms. ln an example embodiment, the user interface 66 may
`
`include one or a plurality oflights, a display, a speaker, a tone generator, a vibration unit
`
`and/or the like, and an input mechanism to enable the user or operator to select various timing
`
`values and/or enable or‘ disable certain functions of the controller 60 as described herein,
`
`{8928}
`
`The processor 62 may be embodied in a number of different ways. For example,
`
`the processor 62 may be embodied as various processing means such as one or more of a
`
`microprocessor or other processing element, a coprocessor, a controller or various other
`
`computing or processing devices including integrated circuits such as for example, an ASlC
`
`(application specific integrated circuit), an FPGA (field programmable gate array), or the
`
`like.
`
`ln an example embodiment, the processor 62 may be configured to execute instructions
`
`stored in the memory 64 or otherwise accessible to the processor 62. As such, Whether
`
`configured by hardware or by a combination ofhardware and software, the processor 62 may
`
`represent an entity (eg, physically embodied in circuitry — in the form ol‘processing
`
`~6—
`
`

`

`WC 2915/ l3976ll
`
`FCllYEEQlJl-l/llifihflid
`
`circuitry) capable ofperlbrniing operations according to embodiments oftlie present
`
`invention Wbil configured accordingly. Thus, for example, when the processor 62 is
`
`embodied as an ASlC, FPGA or the lilte, the processor 62 may be specifically configured
`
`hardware for conducting the operations described herein. Alternatively, as another example,
`
`when the processor 62 is embodied as an executor of software instructions, the instructions
`
`may specifically configure the processor 62 to perform the operations described herein.
`
`{($29}
`
`ln an exemplary embodiment,
`
`the memory 64 may include one or more non-
`
`transitory memory devices such as, for example, volatile and/or non-volatile memory that
`
`may he either fixed or removable The memory 64- may be configured to store information,
`
`data, applications,
`
`instructions or the like for enabling the processing circuitry to carry out
`
`various functions in accordance with exemplary embodiments of the present invention. For
`
`example, the memory 64 could. be configured to buffer input data for processing by the
`
`processor 62. Additionally or alternatively,
`
`the memory 64 could be configured to store
`
`instructions for execution by the processor 62. Among the contents of the memory 64,
`
`applications may be stored for execution by the processor 62 in order to carry out the
`
`functionality associated with each respective application.
`
`ln some cases, the applications
`
`may include instructions for monitoring pressme/i‘lovv to control the pump assembly 30 and
`
`instructions to execute leak detection algorithms as described herein in connection with
`
`FlGS. 2-9 below.
`
`{tltlfitl}
`
`Flt}. 2 illustrates a timing diagram ltlt) showing a number of cycles of the pump
`
`assembly 30 between on and off states.
`
`ln the example of FlG. 2, the predetermined number
`
`ofeyeles, n=6. an indicates an example of the first variation above.
`
`in this regard, when 6
`
`cycles have been experienced, the corresponding time it has taken is examined.
`
`In this
`
`example, 6 cycles occurred in a time tol about 1.75 minutes in the lirst instance ofn cycles
`
`and occurred again in about 1.75 minutes in the second instance of n cycles.
`
`lf the time t
`
`(1.75 minutes) is less than the predetermined threshold period of time, tl,
`
`then leakage is
`
`indicated. Accordingly, for example, if tl is 2 minutes, then 'an indicates a leakage
`
`situation. However, if tl is 1.5 minutes, then an indicates no leakage.
`
`{film}
`
`Vn2 indicates an example of the second variation described above. Thus, there
`
`are multiple rolling counts of cycles from each instance of an on/off cycle (up to a
`
`predetermined maximum numher ofinstances).
`
`If any one ofthe count instances reaches the
`
`predetermined number of cycles (ie, 6 in this example) prior to tl being reached, then a leals,
`
`is indicated.
`
`

`

`W0 2915/139760
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`FC'lYEEQlJld/llifindd
`
`{6932}
`
`According to a third variation? the controller 60 is configured to count cycles for
`
`the period. of time tl.
`
`li' the number ol‘cycles detected in the time period tl is greater than n,
`
`then a lealr is detected.
`
`l-lowever, if the number of cycles detected in the time period tl is less
`
`than n, then there is no lealiage detected.
`
`{iltl33}
`
`According to a fourth variation, arolling series of parallel counting operations are
`
`performed by the controller 60. Thus, each time a new on/ofl‘ cycle is detected, an additional
`
`time measurement is started with the number of cycles counted for the given time period tl.
`
`if any of the parallel measurements achieves the number of cycles detected in the time period
`
`tl that is greater than n, a lealr is detected by the controller 60. For any of the measurements
`
`abovea the controller 60 may stop the pump assembly 30 and/or issue a, notification to the
`
`operator.
`
`ln some cases, the pump assembly 30 may be stopped until the operator initiates a
`
`reset operation? or otherwise takes action to clear the detected, fault (fie, leakage) condition.
`
`{8934}
`
`FlG. 3 illustrates a timing diagram 200 showing a number of cycles of the pump
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`assembly 30 between on and oil states.
`
`in the example of HG. 3, the predetermined
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`threshold period oftime, tl,
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`is 2 minutes. Thus, according to th, which indicates an
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`example of the third variation described above, the number of cycles encountered is counted
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`for 2 minutes (ie, time tl).
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`in this case, 7 cycles were counted in the first instance of
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`counting for 2 minutes. Accordingly, if the predetermined number of cycles, n=6, then more
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`than the predetermined number of cycles was experienced in the time tl, so leakage is
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`indicated, However? if n was aliiglier value (say 8), then th would indicate no leakage.
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`{9935}
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`‘v’tZ indicates an example of the fourth variation described above. Thus there are
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`multiple rolling counts of cycles from each instance of an on/off cycle (up to apredetermined
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`maximum number ofinstances} for a time tl.
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`ll‘ any one of the count instances e *ceeds the
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`predetermined number of cycles tie, 6 in this example) when the time tl is reached, then a
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`leak is indicated.
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`ln some cases, it may he appreciated that a new time measurement could be
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`started at any time and thus, the start of any time measurement period need not be correlated
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`to a particular even such as an on or oil event.
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`{6936}
`
`The above described variations on using the on/off cycles and a measurement of
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`time for leak detection may worlt fairly well in most situations. However, in some cases,
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`some of the consumers 50 may have flow demands that tend to mimic or resemble leakage
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`conditions? which could create a problem for the operator. For example a washing machine
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`maybe the consumer 50 in some cases.
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`In particular, certain newer washing machine models
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`may have water demand, cycles that require short on/off cycles in order to minimize water
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`consumption. Given the potential for demand cycles for water flow being detected at
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`relatively short intervals, it is possible that a newer washing machine (eg, ahigh el‘ficiency
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`machine) may trigger fault detection based on leakage by the controller 60, The operator
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`may become frustrated with continually needing to reset the pump assembly 30 or clear fault
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`conditions at the controller 60.
`
`{tltl37}
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`Clperators dealing with the situation above may deal with the problem by disabling
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`leakage detection if they understand the nature of the problem.
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`l-lowever, it they do not
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`understand what is causing the shutdowns and fault conditions, the operators may return their
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`pump assembly as being defective. Even a sophisticated operator that fully understand the
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`problem and wants to manipulate the operation of the controller 60 (erg, to increase the time
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`period monitored and/or the number of cycles that must be detected for leak indication) may
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`not arrive at a satisfactory solution. For example, if the norrn al detection algorithm detects 6
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`on/otl cycles in 2 minutes to classify a leak, the operator may decide to extend the time and
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`number of cycles to 60 minutes and it’ll cycles. However, it‘ the pump assembly ’50 is
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`connected to an appliance that is opened every 15 seconds and closed again immediately, the
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`pump assembly 30 may be switched on and off according to this cycle.
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`if the cycle is
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`maintained for 45 minutes, 180 switch operations will still be achieved and the controller 60
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`may stop the pump assembly 30 and/or indicate afault condition even if the opening cycle
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`will return to norrn al after the initial 4-5 minute interval, Accordingly, it may he desirable to
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`develop a better way to detect leakage scenarios,
`
`{£3933}
`
`An example embodiment may therefore be provided to. allow any one of the above
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`described leakage determining variations to be employed (or any other version that uses a
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`comparison of the number of cycles in a measurable time period) for an initial status
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`determination.
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`ll' the above described methods indicate a possible leak, then the controller 60
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`may trigger a mode (or state) shift.
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`if there is no state shift, the controller 60 may continue to
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`monitor according to the corresponding variation for leakage determining.
`
`{8939}
`
`in situations where a state shift occurs (_i.e., there is a shift to a ”washer detection"
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`state), a second timer may be started and run for a second time period longer than the first
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`time period tl. The second (longer) time period, tT, maybe used to monitor to determine
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`whether repeated leahage indications are received, or whether at least one non-leakage
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`indication can he received during the time period ti” to indicate that the leakage indication
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`was likely due to equipment used as a consumer 50, instead, of being due to an actual leak.
`
`{6940}
`
`An example embodiment will he described in connection with the flow diagram of
`
`Fit}, 4, Of note, FlG, 4 is based on the first variation above (i.e., th), but it should be
`
`appreciated that the flow diagram could be modified to be based on any of the other
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`variations as well. Referring to FIG. 4, cycles may he counted to determine whether the last
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`6 cycles occurred in a space of time longer than two minutes at operation 300.
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`In other
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`words, a determination may he made as to whether n cycles occurred in time t that was
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`greater than tl.
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`ll it took longer than 2 minutes to achieve 6 cycles, a timer (t) may he
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`stopped at operation 310 and set to tell at operation 305 and operation 300 may he repeated.
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`However, if 6 cycles were achieved in less than two minutes. a state change may occur (to a
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`state that validates a potential leakage condition).
`
`{694]}
`
`The state change may involve modifying the first variation above to test whether
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`any non—leakage indication can he received in a second period of time (egg ti‘ = 60 minutes)
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`that is longer than the first period ol‘tirne (e. a 2 minutes). At operation 320 a determination
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`may he made as to whether t=0 tie, whether the timer is being started or already running).
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`if
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`t=0a then the timer may he started at operation 330 and flow may proceed, to operation 340.
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`if
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`the timer is already running (i.e., t does not
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`0). then flow immediately proceeds to operation
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`340, where it is determined as to whether the longer period of time (eg 60 minutes) has
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`been reached. ll the 60 minute time period has not been reached. then flow returns to
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`operation 300 for another check to see if 6 cycles can he achieved in a period longer than 2
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`minutes.
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`if 6 cycles are ever achieved in the time period longer than 2 minutes while the
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`longer timer count is less than 60 minutes, then flow proceeds to operations 305 and 3] (l and
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`the timer is reset. This may act as a recovery from the state change (i.e., arecoveiy from the
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`validation of the potential leakage condition due to confirmation of no leakage). However? if
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`6 cycles are continually received in less than 2 minutes for the entire 60 minute period, flow
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`will proceed to operation 350 where the timer will he stopped and a fault or error indication is
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`generated at operation 360.
`
`{8942}
`
`FlG. 5 is a modification to the example ol‘ FIG. 4.
`
`in the example of FIG. 5 an
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`additional check may he initiated at operation 370 to indicate that there is no leakage before
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`the timer can he stopped and reset at operations 305 and fill).
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`in other words, two
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`consecutive non-leakage indications must he required to avoid the state change, or to cause
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`the recovery from the state change to be permitted after the state change is triggered (e. g
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`based on receiving a "no" out of operation 300)
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`{illicit};
`
`FlG. 6 is a further modification of the example ofFlG. 5 in which a wait period
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`may he initiated after a first leakage indication is received before checking to see ifa second
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`consecutive non—leakage indication can be achieved. Thus, for example, the :llovv may he the
`
`same as :in Phil. 5 except that a value may he set (eg, x=l) at operation 380 when the long
`
`timer is running and a leakage indication is received (eg, based on receiving a "no" out of
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`~10—
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`operation 300). lfa non—leakage indication isreceived (cg, based. on receiving a "yes" out
`
`of operation 300), while the timer is already running (i,e., x=l) then a wait period may he
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`inserted (eg, 2 rninutes) at operation 390 before performing another lealrage chech at
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`operation 370. However, the