US20080144238A1 - Controller system for pool and/or spa - Google Patents

Abstract

A control system for a pool and spa. Main line voltage is provided through a single line voltage service and a single ground fault circuit interrupter circuit, facilitating a ground fault test and simplifying installation. The control system acts as a power distribution system for controlling the pool and spa equipment, with a circuit board assembly including individual fuse protection devices and switching circuits. A test algorithm is included, wherein the control system is disabled from normal operation if the GFCI test fails. The pool operator manually enters a water fill command, and the controller system automatically opens the fill valve for a predetermined time interval, and then automatically closes the valve. An emergency disconnect switch is mounted near the bathing area, connected by low voltage wiring to the controller system cabinet. The controller system senses the emergency switch closure and disconnects line voltage to the line voltage loads. The emergency switch closure also remotely induces a ground fault, tripping the GFCI. A sensing circuit allows the controller system to sense the presence of the emergency switch system, and issues a warning and prevents normal operation of the pool and spa system if not connected. A gas pressure sensor monitors the natural gas line, and the heater is disabled and a warning given under low pressure conditions. Abnormal filter backpressure triggers a warning when the filter needs service. A temperature sensor has parallel sensing elements in a common housing to provide separate sensing circuits.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS
• This application claims priority from application Ser. No. 10/860,392, filed Jun. 1, 2004, which in turn was a divisional application of application Ser. No. 10/066,868, filed Feb. 4, 2002, which in turn was a division of application Ser. No. 09/451,561, filed Nov. 30, 1999, now U.S. Pat. No. 6,407,469, the entire contents of which applications are incorporated herein by this reference.
BACKGROUND
• Electronic control systems have been employed to control various functions. Typically, however, the power hookups for the different components associated with the pool or spa have been run directly through circuit breakers in a main or auxiliary panel to the various components, such as the pump, heater and lights. This is a time consuming task, and one which can lead to wiring mistakes, in view of the number of wiring connections which need to be made. There is therefore a need to simplify the power hookups to the various components, in order to control costs and provide more reliable installations.
• A problem with pools is maintaining the level of water within the pool. Evaporation losses can be significant, and so it is advantageous to have an automated system for keeping the water level at a given desired level. Stand alone systems for doing this are known, but tend to be somewhat complex. It would be advantageous to integrate such a system with the pool controller, for reliability, ease of installation and cost savings.
• Emergency shutoff switches are typically mounted close to the spa, to enable quick shutoff of pumps and other functions in an emergency. It would be an advantage to provide an electrical shutoff switch which did not require high power connections to the switch, and whose installation could be verified by the controller.
• Ground fault circuit interruption devices are typically employed in pool and spa controls. It would be an advantage to provide a technique for testing for proper operation and installation of these circuits.
• The pool plumbing system typically includes a filter system for removing particulates from the pool or spa water. These commonly use diatomaceous earth or other filtering agents. As the filter becomes filled with particulates removed from the water, the filter back pressure rises, and ultimately for proper operation the filter must be cleaned, e.g. by backflushing the filter. Presently, a sight pressure gauge is mounted on the filter, so that the pool maintenance technician can visually check the back pressure status. It would improve the maintenance of the filter operation to automate the pressure reading.
• The water circulation system for the pool/spa also includes a heater for warming the pool and/or spa water for the user's comfort. This heater is typically gas-operated, and does not operate properly when the gas pressure is too low. It would therefore improve the reliability and operation of the water circulation system if a technique could be found to monitor the gas pressure and provide a message and/or control signals in the event of a low gas pressure condition.
• Power loads imposed by the pool system's electrical components can be considerable. Techniques for efficiently using the power load rating of the control system are therefore needed.
BRIEF DESCRIPTION OF THE DRAWING
• These and other features and advantages of the present invention will become more apparent from the following detailed description of an exemplary embodiment thereof, as illustrated in the accompanying drawings, in which:
• FIG. 1 is a diagrammatic view of a pool and spa system utilizing aspects of this invention.
• FIG. 2 is a simplified block diagram of elements of a pool service system embodying this invention.
• FIG. 3 illustrates a control panel cabinet for housing the pool controller and power distribution system of the pool service system, and the service control panel mounted on the cabinet.
• FIG. 4 is a diagrammatic view of the pool control panel comprising the system ofFIG. 2.
• FIG. 5 is a diagrammatic view of the spa control panel comprising the system ofFIG. 2.
• FIG. 6 is a detailed block diagram of the pool service ofFIG. 2.
• FIG. 7 is a top view illustrating a portion of the multilayer conductive trace pattern of the controller circuit board.
• FIG. 8 is a cross-sectional view taken along line8-8 ofFIG. 7.
• FIG. 9 is an isometric view of the connector terminal block used in the control cabinet for connecting line voltage wiring.
• FIG. 10 is a top view of the control cabinet ofFIG. 3, which the cover in a open position illustrate the controller circuit board and line voltage and low voltage connections, and the main compartment bay and the two side compartments through which low voltage wiring is passed.
• FIG. 11 is a cross-sectional view taken along line11-11 ofFIG. 10.
• FIG. 12 is a cross-sectional view taken along line12-12 ofFIG. 10.
• FIG. 13 is a schematic diagram of a simplified pool service system in accordance with the invention.
• FIGS. 14A-14F are simplified flow diagrams illustrating salient program features of the controller comprising the system ofFIG. 2.
• FIG. 15 is a simplified schematic diagram illustrating the GFCI test circuit comprising the system ofFIG. 2.
• FIG. 16 is a schematic diagram of an emergency disconnect switch in accordance with an aspect of the invention.
• FIG. 17 is a schematic diagram of a temperature sensor in accordance with an aspect of the invention.
• FIG. 18 is a diagrammatic view of the temperature sensor ofFIG. 17.
• FIG. 19 is a bottom view of the circuit board comprising the temperature sensor ofFIG. 17.
• FIGS. 20A-20C are circuit schematics of an exemplary embodiment of a controller board comprising the system ofFIG. 2.
• FIG. 21 illustrates connection of two 120 Amp line voltage loads using a 240VAC 50 Amp service.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
• FIG. 1 is a diagrammatic view of a pool and spa system utilizing aspects of this invention. In this embodiment, thepool1 andspa2share filter77 and heater78 through a plumbing arrangement including three-way valves70 and72, although other arrangements can be employed, such as separate heaters and filters for thepool1 andspa2. Aconventional skimmer3 is included, and itsdrain line7 and the pool drain line6 are joined at a junction tee before connection to one input of thevalve70. The drain line5 from the spa is connected to the other input ofvalve70. The valve output is connected to the input side of thefilter pump80 throughwater line8. Awater line9 runs from the pump output to the filter input. The filter output is connected bywater line10 to the heater input. The heater output11 is connected to the input of the three-way valve72. One output of the valve is connected towater line12 leading to a pool inlet. The other output ofvalve72 is connected towater line13 leading to a spa inlet.
• The system includes pool andspa lights90A, yard lights90B, and a decorative fiberoptic lighting system88 typically mounted along the pool coping.
• To the extent just described, the pool and spa system is conventional. In accordance with aspects of the invention, a controller andpower distribution system100 is provided, which controls operation of thesystem50, and which receives AC line voltage service, and distributes line voltage to the line voltage loads, including the heater, pump, lights and fiber optic lighting. Thecontroller100 further controls the operation of the line voltage loads, and thevalves70 and72. Moreover, thecontroller100 receives input data from a variety of sensors, including a gateopen alarm218, apool cover alarm216, water pressure sensors208A (filter input pressure) and208B (filter output pressure),gas pressure224 for thegas supply line15 to the heater, temperature sensor204 (temperature of water entering the heater), temperature sensor206 (temperature of water leaving the heater), and water ph and oxygen reduction potential (ORP)sensors212 and214 in thewater line8. Amaster control panel102 is coupled to thecontroller100 for providing a display and command and data input device by which thesystem100 communicates with a user. The locations of the various sensors may vary depending on the installation. For example, thewater temperature sensor204 may alternatively be placed at the inlet to thepump80, in the water line between thevalve70 and thepump80.
• FIG. 2 is a simplified block diagram of apool service system50 embodying this invention. This embodiment will be described in the context of a residential pool with spa as illustrated inFIG. 1, although it is to be understood that the system can be utilized with larger pool installations, such as hotel/motel pool systems and the like. The system includes the controller andpower distribution system100, which receives AC line power from the main or sub linevoltage distribution panel102. In this example, thepanel102 supplies 50 Amp service online voltage wiring60A, which is connected to a ground fault circuit interrupter (GFCI)circuit62, and then throughline voltage wiring60B to the controller andpower distribution system100. As will be described in further detail below, thesystem100 distributes line voltage power to various line voltage loads, and also includes a low voltage transforming function to provide low voltage AC and DC power at various low voltages need by the electronic devices and low voltage loads.
• In contrast to prior techniques for wiring up pool equipment, the main line voltage power is provided through a single main linevoltage service connection60A,60B andGFCI62 tosystem100, rather than through a plurality of line voltage service connections each with its own GFCI circuit and circuit breaker circuit. This simplifies the wiring effort and labor involved in a new installation. Thesystem100 is not limited to the 50 Amp main line service, and can include auxiliary line services64 and66, which can be used to power auxiliary loads through conventional circuit breaker-protected connections. Typically these auxiliary connections are made on auxiliary circuit boards mounted in the control cabinet.
• Thesystem50 will typically also include the masterpool control panel102 as well as aspa control panel104. The pool control panel can be located inside the residence, adjacent a door leading out to the pool, or in other locations convenient for the user. The pool control panel could also be installed on the cover of thecontroller cabinet112. Thespa control panel104 is typically located adjacent the spa for convenient access by spa users.
• FIG. 3 illustrates acontrol panel cabinet110 for housing thesystem100, and which also includes aservice control panel112, which includesseveral touch switches112A and status indicator lights112B. Techniques for constructing a suitable control panel are described in U.S. Pat. No. 5,332,944. The switches permit user commands to be entered at thecabinet110. If the pool control panel is mounted on the cover of thecabinet110, the service panel would be omitted. Theservice panel112 in this exemplary embodiment includes eight manually actuated control switches/buttons. These are used to turn on or enable the filter pump, the pool and spa lights, the heater, and five auxiliary buttons which can be used for such features as the cleaner pump, yard lights, an auxiliary valve, a fiber optic decorative lighting system and an auxiliary pump. The service panel is located on the exterior of the hinged lockable cover for thecabinet110, and is fully water resistant. This mounting provides a significant safety benefit, since the pool service professional or homeowner does not need to open thesystem cabinet112, exposing line voltage wiring, in order to do routine pool maintenance.
• FIG. 4 illustrates themaster control panel102, which in this exemplary embodiment includes an LCD orother display102A, panel switches102B and indicator lights102C. Thispanel102 includes a display for displaying to the operator various status information and messages, and controls which permit the operator to enter commands or input data to thesystem100. The switches accept user commands and inputs, to initiate system actions or enter information into thecontroller100. For example, the switches or buttons can include up and down buttons for temperature control and programming, a filter button for activating the filter pump, a light button for controlling the pool and spa lights, a spa button which controls thevalves70 and72, turns on the spa jet pump, and turns off the cleaner pump if the system is so equipped, a heater enable button to enable operation of the heater, a program button to put the system in a programming mode, and five auxiliary buttons which can be used for such features as the cleaner pump, yard lights, an auxiliary valve, a fiber optic decorative lighting system and an auxiliary pump.
• FIG. 5 is a similar view of thespa control panel104, which also includes an LCD orother display104A, panel switches/buttons104B and indicator lights104C, which accepts user commands and inputs, to initiate systems actions or enter information into thecontroller100. In an exemplary embodiment, there are four buttons, one button for temperature control, one button to control the spa jets (valves and filter pump) and an optional jet pump, a spa light button, and an auxiliary button. Thepanel104 is mounted in or near thespa2, above the water line. A low voltage cable runs from the panel to thecontroller system100.
• FIG. 6 is a schematic block diagram of thepool service system50. The service system includes a number of components which require electrical power for operation and/or control. In accordance with an aspect of this invention, the electrical power at line voltage is routed through a pool controller andpower distribution system100. Primary electrical power is by the 50 Amp primary service60 from the main panel or 100Amp sub panel40. Of course, the particular ampere ratings for the circuits of this system are merely exemplary, and could be varied in accordance with the demands of particular applications. The primary service60 is provided with a ground fault continuity interrupt (GFCI)circuit62, to provide ground fault protection for the primary power service to the system. Auxiliary electrical power service is provided in this example by a 20 Amp service line64 and a 30 Amp service line66, although the auxiliary service can be omitted for many applications.
• The primary line voltage service60 is provided by a 240 VAC line feed, comprising in a typical installation a neutral conductor, a ground conductor, a first voltage phase conductor and a second voltage phase conductor. These conductors are conventionally color coded, so that according to the coding convention, the ground conductor has green insulation, the neutral conductor has white insulation, the first voltage phase conductor has black insulation and the second voltage phase conductor has red insulation. The black conductor has a first polarity phase with respect to the neutral conductor, and the red conductor has a second polarity phase with respect to the neutral conductor, and 180 degrees different from the phase of the first polarity phase, such that 120 VAC is developed between the neutral and the black conductors, 120 VAC is developed between the neutral and the red conductors, and 240 VAC is developed between the black and the red conductors. In the embodiments described below, the 50Amp service60B includes red conductor60B1, black conductor60B2, white (neutral) conductor60B3, and green (ground) conductor60B4 (seeFIG. 9).
• Various components which are controlled and/or receive electrical operating power through thesystem100 are shown inFIG. 6. These components can include thevalves70,72,74, the pool fillspout valve76, thepool water heater78, thefilter pump80, thecleaner pump82, an auxiliary pump84, aspa jet pump86, the decorativefiber optic system88,lighting system90,spa blower92 andauxiliary lights94. The foregoing particular components is an illustrative listing; for any given pool installation, some of the components will be omitted, and other components may be added, all depending on the design of the particular installation.
• Thepool controller100 receives input data signals from various sensors and input sources. These include several temperature sensors, theair temperature sensor202 for providing ambient air temperature, thewater temperature sensor204 for providing the temperature of the water at the input to the heater, and thewater temperature206 for providing the temperature of the water at the output of the heater. Other sensors include the filterbackpressure sensor system208 comprising pressure sensors208A and208B,ORP sensor210,pH sensor212, water level sensor214 for providing a pool water level indication, a “cover off”sensor216, a “gate locked”sensor218, asolar sensor220 for detecting the temperature at a solar heater, and anemergency stop switch350, to be described in greater detail below. As is known in the art, the controller can respond to the solar temperature, to actuate a valve to divert water to pass through a solar heater, if the installation is so equipped, instead of through the gas water heater. The water level sensor for example can include a probe which extends into an area at which the water level will reach at a desired fill level, and sense the presence or absence of water at this level.
• In accordance with an aspect of the invention, a direct 50 Amp line power connection is made between themain panel40 for the residence directly to the pool controller anddistribution system100, through the 50Amp GFCI circuit62. Thesystem100 has thereon the necessary terminal connections for direct connection of the line voltage service conductors (black, red, white, green) for the 50 Amp service. Circuit protection for the various devices such as theheater78,filter pump80,cleaner pump82 and auxiliary pump84 is provided by circuit protection devices, e.g. fuses, mounted on the pool controller circuit board in the pool controller cabinet. This results in substantial savings and cost and in assembly time and effort.
• A typical power connection in accordance with this aspect of the invention is illustrated inFIGS. 8-12. To facilitate the connection of power to the controller board, an insulatingterminal block240 is employed within thecontroller cabinet110, which carriespressure connectors242 and24 to which the red and black line voltage conductors are attached. Theconnectors242,244 each include aframe242B,244B into which the end of the respective line voltage conductor is inserted. A threaded device such asset screw242C,244C is then advanced into the frame, capturing the end of the line voltage conductor in the frame by a pressure connection.
• Theterminal block body240A is fabricated of an electrically insulating material, i.e. a dielectric, and is mounted to the floor of the cabinet. The terminal block includes mounting surfaces which receive threadedfasteners251 to secure the controller circuit board to the terminal block, and through pressure contact, make electrical contact with the red and black line voltage connectors. Anupstanding wall portion240B protrudes upwardly, through a slot250A formed in the edge of thecircuit board250. Thewall portion240B registers the position of the terminal block in relation to the circuit board, and also physically provides dielectric isolation between the line voltages carried by theconnectors242 and244 carry.
• Conductive traces on thecircuit board250 contact respective linevoltage connector surfaces242A and244A (FIG. 9) of theconnectors242 and244 to provide electrical continuity between the circuit board traces and the red and black line voltage conductors. Representative circuit board traces are shown inFIGS. 7 and 8.
• FIG. 7 is a simplified bottom view of thecircuit board250, and illustrates printed wiring conductor patterns for carrying line voltage at 120V, at the respective first phase and the second phase.Circuit trace252 is connected to thered wiring connector242, and includes pad252A exposed on thebottom surface250B of the board, for contacting connector surface242A upon assembly of the board to theterminal block240.
• In this embodiment, thecircuit board250 is a multiple-layer structure, with conductor traces formed on the top surface, the bottom surface and in a buried intermediate layer, using known photolithographic techniques, with conductive vias interconnecting the circuit traces on the different layers as required to form the desired circuit. Thecircuit trace252 is mostly formed in the buried layer, and is shown in phantom lines inFIG. 7. Thus, thecircuit trace pattern252 is generally a buried layer, except for conductive pad252A formed on thebottom surface250B. Thetrace pattern252 then transitions through a conductive via to a buried layer, sandwiched between layers of dielectric comprising theboard250. This is shown in the cross-sectional view ofFIG. 8, whereintrace252 is sandwiched between boarddielectric layers250C and250D. Thecircuit trace254, connected to the black conductor60B3 throughconnector244, is a surface trace pattern, and is shown in solid line inFIG. 7.
• Thecircuit board250 thus includes layers of printed wiring patterns, which route the line voltage and low voltage signals to respective devices mounted on the board, and to the connectors to which are connected wiring running to the line voltage loads and low voltage devices. By use of this circuit board arrangement, the labor involved in wiring a given installation is substantially reduced, and the circuit board can be easily removed for servicing, if necessary.
• To facilitate the safe routing and separation of low voltage conductors from high voltage conductors, thecabinet110 for thesystem100 is separated into three compartments or bays, twolow voltage compartments110J and110K on either side of the middle compartment110I. Thecabinet110 in this embodiment is a metal housing structure having a hingedcover110A, side walls110B-110E and floor110F. Interior metal wall partitions116G and110H of the cabinet define the three compartments. All line voltage wiring enters the cabinet at the bottom wall through holes formed in wall110B, and remain in the main compartment. The ends of the line voltage wiring are captured in pressure connectors, including theconnectors242,244. Pressure connectors suitable for the purpose are commercially available, e.g., a pressure connector marketed by Connector Mfg. Co. of Alabama, Grenville, Ala., as part number CA-66. Low voltage wiring is brought from the main compartment through openings in the side walls and through wall110B at openings in the side compartments. This results in improved safety, since any failure of insulation on a line voltage line could cause a dangerous voltage on the low voltage lines.
• FIG. 13 is a simplified wiring diagram for an exemplary pool and spa installation. For some installations, not all sensors and controlled devices may be needed or desired by the owner, and the system shown inFIG. 13 does not explicitly show the identical complement of controlled devices and sensors as shown for the system ofFIG. 6. It is contemplated that the same controller circuit board will be used in this installation as well as in the system shown inFIG. 6. The exemplary installation ofFIG. 13 includes controlledvalves70 and72,air temperature sensor202,water temperature sensor204 which measures the temperature at the inlet to the heater, which should be the same as the water temperature in the pool or spa,spa jet pump86,filter pump80,water heater78,spa lights90A andyard lights90B.
• Thecircuit board250 is diagrammatically depicted inFIG. 13, and is connected to theline voltage connectors242 and244, attached to theterminal block connector240. Theneutral bus246 is attached to the terminal block, and a neutral connection246A is made to the circuit board. The neutral (white) conductor60B3 from the 240 VAC,50A service is connected to the neutral bus. The ground (green) conductor60B4 from the50A service is connected to aground bus248 attached to themetal cabinet110. Theboard250 includes printed wiring conductor patterns which connect the various circuit devices mounted on the board and the connector terminals.
• Theboard250 is supported on themetal cabinet110, and ground is connected through metal threaded fasteners258 (FIGS. 10-12) which secure the board in place. Extending from thesidewall partitions110H and110G are metal brackets comprisingshelf portions110L and110N, supported bymetal leg portions110M and110P, respectively. Thefasteners258 secure theboard250 to the shelf portions. Thus, the board is physically connected to thecabinet110 by four threadedfasteners258, and to theterminal block240 by four threadedfasteners251, in this exemplary embodiment. This attachment technique facilitates the installation and removal of theboard250 relative to the cabinet. Of course, other types of removable fastener structure could alternatively be employed instead of screw fasteners, including clamps, spring clips, friction connectors, and the like.
• The exemplary installation illustrated inFIG. 13 includes two 240 VAC loads, thespa jet pump86 and thefilter pump80. These loads are connected to 240 VAC service through a 240 VAC connector260 comprising afirst connector structure260A (FIG. 10) mounted on the top surface of the circuit board, and a removable connector structure260B (FIG. 13) to which insulated conductors or wires are connected running to the loads. The respective connector structures have respective pins and corresponding plug receptacles which mate together when the connector structure are mated. Such connectors are well known; a suitable connector is the connector marketed by RIA Electronics, Inc., Etherton, N.J., as mating parts 31041208 (pin connector) and 31007208 (plug connector). Use of this type of connector structure facilitates field wiring of the line voltage loads.
• Respective terminals of theconnector structure260A are electrically connected to printedwiring trace252 running to theconnector242, and other connections to other terminals of theconnector structure260A are made through switching relays and fuses towiring trace254 to theconnector244. By appropriate connection to respective terminals of the connector structure, 240V service is available.Insulated conductor86A is connected to a “red” terminal connection, i.e. a connection which is electrically connected toconnector242, to which the red conductor of the 240V service is connected.Conductor86B is connected to a “black” terminal connection, i.e. a connection which is electrically connected through a relay and fuse toconnector244, to which the black conductor of the 240V service is connected. Conductor86C connects theground bus248 to the spa jet pump.
• Similar connections are made to thefilter pump80 to provide 240V service. Thus,wire80A is connected to another “red” terminal connection on connector260B,wire80B is connected to a “black” terminal connection on connector260B, and wire80C connects theground bus248 to the filter pump.
• The 240 VAC loads are controlled by respective switch devices, e.g. non-latching relays, in turn controlled by the system controller. Each load circuit is also protected from excessive current draw by a fuse device. Thus, the spa jet pump is controlled byrelay280 and circuit protection is provided byfuse286, respectively mounted on thecircuit board250. To accomplish this, a series circuit connection is made between thecircuit trace254,relay280 and fuse286 to the corresponding terminal onconnector structure260A, using solder connections to wiring traces formed as part of theboard250. Thefilter pump80 is controlled byrelay282 and circuit protection is provided byfuse288. A spare 240V service circuit is provided, withrelay284 andfuse290.
• Thecircuit board250 further has a 120V service connector270, also comprising a fixedconnector structure270A mounted to the board, and aremovable connector structure270B (FIG. 13) connectable to the fixed connector structure. These connector structures can be implemented in the same manner as theconnector structures260A and260B, further facilitating field wiring of the controller system. Insulated wires running to the load devices are attached to theremovable connector structure270B. Respective terminals of theconnector structure270A are electrically connected via wiring traces of the circuit board to thered connector242, theblack connector244 and theneutral connector272 in turn connected to theneutral bus246 via wire246A. Thus, 120V service of either phase (red or black) is available at the connector270. Theheater78 is wired to the connector270 by wires78A,78B. When the controller system calls for heat, 120 VAC power to activate the heater is supplied, which enables all ignition and temperature regulating functions of the heater. The heater in turn ignites gas supplied to its internal gas valve and burner, heating the water which is flowing from the pump and filter. Thespa light circuit90A are connected to a black polarity connection at connector270 by wire90AA, and to theneutral bus246 by wire90AB. The yard lights90B are connected to a red polarity connection at connector270 by wire90BA, and to theneutral bus246 by wire90BB. Provision is made for an optional120V load device238, which can be connected to connector270 bywire238A, and to theneutral bus246 by wire238B.
• Each 120 VAC circuit connected through the connector270 is controlled by a switch device actuated by thecontroller402, with circuit protection provided by a corresponding fuse, respectively mounted on thecircuit board250. The switch device and a corresponding fuse are connected in series between a corresponding line voltage wiring trace (i.e., black, red, white) and a terminal of the connector270. The heater is controlled byrelay300, with circuit protection provided byfuse292. Theoptional load238 is controlled byrelay302 and protected byfuse294. Theyard light circuit90B is controlled by relay304, and protected byfuse296. Thespa light circuit90A is controlled byrelay306, and protected byfuse298.
• The various electrically-powered components controlled and powered through the pool control system can give rise to power load issues, where the total current available through the pool control system could be insufficient to meet all load conditions. To provide power to the120V lighting90, two different120V light circuits90A and90B are hardwired on the control board. One circuit, say90A, is powered by connection to the black and white conductors of the 240 AC service. The second circuit is powered by connection to red and white conductors of the 240 VAC service, thus using a different phase of the 240 VAC service. With this arrangement, even though both circuits each draw up to 10 Amps at 120 VAC, the total power rating for both circuits is 10 Amps at 240 VAC.
• This feature of the invention is described with respect to the simplified schematic ofFIG. 21. The rating of a 50Amp 240 VAC circuit in the United States is achieved with two 120 VAC waveforms, which are 180 degrees out of phase. Thus, consider the node RAC (which could be connected to the red conductor of the 50 Amp service) to be at +120VAC, and the node BLAC (which could be connected to the black conductor of the 50 Amp service) to be at −120 VAC. The voltage difference between the two nodes is thus the 240 VAC service, and the load L1 is a 240 VAC load. Current can flow through the load L1 to a maximum of 50 Amps in this 50 Amp circuit. However, if the total current through the load L1 is less than 50 Amps, the balance can be directed through loads L2 and L3, connected between RAC and the neutral conductor, and between BLAC and the neutral conductor, respectively. Loads L2 and L3 may or may not be equal, and the return path is through the neutral conductor, unused if all 50 Amps is not passed through the load L1. However, the total current passing through plane P-P is always 50 Amp. When loads L2 and L3 are equal, they act as virtual grounds for each other, and no current flows through the neutral leg. If these loads are unbalanced, the difference flows in the neutral leg to make up the 50 Amp current.
• Thesystem100 further includes a transformer coupled to the 120V AC to provide low voltage DC power at 5V and 15V to provide power to the electronic components including the controller, and to operate the low voltage load devices, such as thevalves70,72. The transformer is connected to thecircuit board250 to receiveinput 120V AC, and to provide the low voltage AC and DC supply voltage levels.
• To further facilitate field wiring of thecontroller system100, theservice control panel112, thecontrol panel102 and thespa control panel104, the sensors, and the low voltage loads such as the valves, are connected to thecircuit board250 by low voltage cables and modular, telephone-jack-type connectors. In this way, the low voltage cables can be connected or disconnected easily by simply detaching removable connector portions from corresponding connector portions mounted on the board. Thus, referring toFIG. 13, for example, thecontrol panel102 is connected to the board20 by a low voltage,multiple conductor cable102D and amodular connector102E having a male portion connected to the cable end and a female portion mounted to theboard250. The male portion is latched in place in the female portion, making electrical contact with the respective conductors, and can be detached by pressing a plastic latch tab and pulling the male portion away. Similar connections are made to thespa panel104 and theservice panel112, through respective cables104C,112C andmodular connectors104D,112D. Modular board connectors suitable for the purpose are commercially available, e.g. the telephone/data type connectors marketed by Berg as part numbers 93899-001 (6 position board connector) and 69255-001 (eight position board connector). The mating male connector structures attached to the cabling are also commercially available.
• Similarly, the sensors and low voltage loads are also connected to the boards using modular connectors. The leads for these devices are connected to male connector structures, which are mated to respective female connector structure mounted on the board. For example, the wiring forvalve70 is connected to the board bymodular connector structure70A, and the wiring forsensor204 is connected to the board bymodular connector204A. Suitable connector structures forsensor connector70A include the Molex part numbers 705-43-0106 (board connector structure) and 14-56-8022 (wire connector structure). Suitable connector structures for valve wiring connectors include JST part numbers JST-32B-XH-4 (board connector structure) and JST-02NR-E2R (wire connector structure).
• The low voltage cabling for the control panels is routed from the main bay110F of the control cabinet, through window opening110H1 formed in sidewall110H and into the low voltage secondary bay110K of the cabinet, as shown inFIG. 10. Thecable112D can be connected to thepanel112 on the front cover, and thecables102D,104D can be passed through service opening(s) formed in the bottom wall110B of the cabinet and then routed to therespective panels102 and104. Similarly, the low voltage wiring for the low voltage loads is passed from the main bay110F through window110G1 ofsidewall110G into the right low voltagesecondary bay110J, and then routed through service opening(s) formed in the bottom wall110B of the cabinet for routing to the low voltage loads and sensors.
• An aspect of this invention is the use of a controller system which is readily field wired, providing significant saving in installation labor. Theboard250 can be removed from thecabinet110 easily, without disconnecting the line voltage conductors60B1-60B4. This is accomplished by removing thefasteners258 which secure the board to the cabinet, removing thefasteners251 which connect the board to theterminal block240, and disconnecting the line voltage and low voltage connectors. This can be done in a matter of minutes, and thus facilitates servicing thesystem100. If aboard250 is malfunctioning, it is a simple matter to remove it for repair or replacement in the field. Moreover, because the line voltage conductors60B1-60B4 need not be physically disconnected, the safety hazards involved in such work are reduced.
• In an exemplary embodiment, thecontroller system100 includes amicroprocessor402 such as a Pic 16C65A CMOS microcomputer marketed by Microchip, which accepts information from a variety of sensors and acts on the information, thereby operating according to instructions described more fully inFIGS. 14A-14F. The invention is not limited to the use of a controller including a microcomputer or microprocessor, whose functions can instead be performed by other circuitry, including, by way of example only, an ASIC, or by discrete logic circuitry.
• An exemplary main operational routine700 illustrating the programmed operation of themicroprocessor402 is shown inFIG. 14A. After system powerup (702), a “check GFCI”subroutine704 is performed. This subroutine has for its purpose to electronically test whether theGFCI62 is properly operational, and is described more fully with respect toFIGS. 14B and 15. Upon successful completion of GFCI test, the main program is run (706). The main program performs the control functions needed for running the various pool and spa functions, including running the heater and pump. The primary function of the main program is to monitor safety issues, such as over-temperature conditions. Thus, the main program will manage water temperature in the pool and spa. Other functions performed in the main program are to monitor the clock and real time to determine when to activate features, e.g. lights, heater, and the like in accordance with a programmed time schedule. The microprocessor is user-programmable to set up the schedule. U.S. Pat. Nos. 5,361,265 and 5,559,720 describe techniques for programming microprocessors in a spa environment.
• The routine700 performs an interrupt (708) of the main program every 16 milliseconds in this embodiment. As part of the interrupt routine, the system time, kept by an incremental timer, is incremented (710) by adding one to the internal stack of the counter, and the control panel buttons are checked (712) to see for activation. If none of the buttons have been pressed or otherwise activated, operation returns (714) to the main program at the point of interrupt. If any control panel switches have been activated, then thepanel service subroutine716 is entered. This panel service subroutine activates features, and accepts and inputs and alarms entered via panel switches. The panel push-button impulse, generated by the electronic panel circuitry, is several hundred milliseconds long. Since the interrupt is every cycle of the line power supply, or approximately every 16 milliseconds, the processor has ample time to detect a button push and respond accordingly. The processor loads the data represented by a button push, and loads that data into a register. This register is then accessed by the microcomputer every few milliseconds and appropriate action is taken. After completion of the panel service subroutine, the emergency disconnect routine is entered (718), and thereafter operation returns (714) to the main program to the point of interrupt.
• TheGFCI test routine704 is described further with respect toFIGS. 14B and 15. According to this aspect of the invention, thesystem100 will test for proper connection and operation of theGFCI62. This is done in the exemplary embodiment by inducing a ground fault shortly after power up of the system, and then looking for GFCI interrupt within a specific short time. If this does not occur, thecontroller100 will display a type of “GFCI absent” message and accept no further inputs from the control panels, preventing further operation of thesystem50. If an interrupt does occur, this event will be stored in a nonvolatile memory as a flag. Then, when the system is re-powered up, the stored flag information will be read, the system will know a GFCI is installed, and thesystem100 will operate normally.
• Thus, when thesystem100 is powered up the first time after installation, it will wait a short time, say five seconds to ten seconds, and conduct a GFCI test to determine whether theGFCI62 is operational.FIG. 15 illustrates schematically circuit elements employed for this test. TheGFCI62 is a well known apparatus, and includessense coil62A,relay62B and control circuit62C. Thesense coil62A is coupled to conductors of the 50Amp service60A. In the event of a current imbalance between the incoming and outgoing current in the line voltage service, the control circuit will sense this condition throughcoil62A, and open therelay62B, interrupting power. The function of a GFCI is well known in the art.
• Thecontroller100 includes avoltage transformer circuit480 will transforms the 120 VAC input line voltage to a 12 VAC level. This 12 VAC is applied to a voltage divider, and the sinusoidal divider voltage drives the input to gate484, which converts the sinusoidal input signal to a square wave signal between 0 V and +5 V. The microprocessor monitors the square wave signal, and will sense nulls in the power waveform to switch the relays at zero crossings in the power waveform to minimize arcing in the relays.
• An output port of themicroprocessor402 is coupled to arelay358. One switched port of the relay is connected atnode368 to one 120 VAC wire; the other switched port is connected to earth ground. Apower supply406 provides a dc power supply voltage from the line voltage transformer to power the microprocessor. Also connected to the microprocessor is a nonvolatile random access memory (RAM), e.g. anEEPROM memory404.
• The GFCI test is performed by themicroprocessor402 providing a control signal to turn ontransistor405, closing therelay switch358B and shorting the line voltage atnode368 to earth ground through a 10Kohm resistor362. This will create an imbalance in the power supply lines60A1 and60A2. If theGFCI62 is present and properly connected, theGFCI relay switch62B will be opened, interrupting power to thetransformer480. Themicroprocessor402 will sense this condition, through its monitoring of thegate482 output, and in response to lack of a square wave signal will store a flag bit in theEEPROM404. This will occur before the microprocessor loses power. The next time thesystem100 is powered up, the startup program routine will look for this bit, and if set will proceed to execute the main program. However, if the flag is not set, the GFCI test will be performed.
• TheGFCI62 must open the circuit within a certain time period after a short or imbalance is detected. For example, for a Class A GFCI, the rated time period is 7 milliseconds, and for a Class B GFCI the rated time period is 20 milliseconds. Therefore, there must be a start time for the test and a finite period of time after therelay358 is closed to indicate a successful test. Because each cycle of the60 cycle line voltage supply is 16 milliseconds long, the microprocessor must wait a certain time period, time A, before closingrelay358. The signal input for the start of the time period A is the square wave fromgate482, connected to thetransformer480, which generates an AC signal proportional to the line voltage supply, but isolated from the line voltage supply.
• The time period A can vary from 1 millisecond to 15 milliseconds in this embodiment. Time interval B is the time period before checking for another input from the gate, i.e. a rising edge or high state on the square wave signal. Time interval B can vary from 1 millisecond to several hundred milliseconds, but will generally not exceed 100 milliseconds.
• When themicroprocessor402 has begun the time B countdown, it looks for one input on the gate waveform. If it continues to see rising or high inputs on the gate waveform, indicating that the GFCI relay has not opened, the microprocessor will wait the entire time B, and then branch to a lockout program. This program will set an error message to the main control display panel such as “GFCI FAIL,” and stop further input or operation.
• If there is a power shutdown during this wait time B, the microprocessor will write a flag bit to thememory404, to indicate a successful test. As the power to the microprocessor is shut off, a short term power supply back supply, shown schematically ascapacitor408 andresistor410, will give themicroprocessor402 sufficient time to finish the wait time B, and set the GFCI flag in thememory404 before shutdown.
• FIG. 14B shows theGFCI subroutine704 in further detail. After system powerup at702, the GFCI flag bit memory location in thememory404 is checked (704A), and if set, operation returns to the main program (704B). If the bit is not set, then at704C, the microprocessor monitors the gate output to detect a rising input from the gate. Once this is detected, after a wait of time interval A, therelay358 is closed (704D). Now the microprocessor waits for time interval B (704E), and then checks for a rising input from the gate (704F). If a rising input is not detected, then the GFCI flag bit is set (704G), and thesystem100 will shut down. If a rising input is detected, indicated that the power was not interrupted, then a “GFCI FAIL” message is displayed (704H), and the system is locked (704I), preventing further operation or input. Typically, all functions are disconnected or disabled, except the water pump, which is needed for freeze protection.
• An aspect of the invention is to integrate with thepool controller system100 the circuitry or logic necessary to respond to user commands to activate thefill valve76 to dispense water into the pool from the water line. The controller is responsive to a manual control panel selection by the user to actuate the fill valve, say by actuation of panel button102B1 (FIG. 4), and release water into the pool to replenish the water. The controller starts an internal timer, and then after a predetermined timer interval elapses, or a time desired by the user, shuts off the valve to stop filling the pool with water. This will address the problem of the pool owner manually turning on a fill valve, and then forgetting to later turn off the valve. Alternatively, a water level sensor detects a low water level condition, and automatically activates the fill valve for a predetermined time interval. As an additional optional protection against overfilling, the water level sensor can sense an overfill level, and provide a signal to the controller indicative of this condition. The controller acts on the overfill signal to close the fill valve, even though the predetermined timer interval has not elapsed.
• The pool fill feature is illustrated in the flow diagram ofFIG. 14C. During an interrupt (708) from the main program, the “activate features”subroutine718 is entered. One of the features is the “pool fill” feature; of course there can be other features activated during this interrupt, not pertinent to the fill routine. If the user enters a pool fill command through one of the control panels, by activating one of the panel switches, for example, then the pool fill feature is selected (718A). If the pool fill feature is not selected, operation returns to the main program, or to another feature. At718B, the fill time is selected. The user can enter this data through the control panel, e.g. in increments of minutes, or a default fill time can be used, e.g. 30 minutes. In the later event, operation can proceed fromstep718A immediately to step718C, to open the valve. Otherwise, the time is set, and then the valve is opened, with the microprocessor starting a timer for timing out the selected or default fill time interval. At this point, operation returns to the main program.
• A function of themain program706 is to monitor the fill activity once started. Thus, atperiodic step718D, a check will be made for the status that a fill has already been activated. If not, operation returns to the main program. If a fill operation has been started, the timer is checked atstep718E. If the fill time has not expired, operation returns to the main program. If the fill time has expired at718E, the fill valve is closed (718F), and operation returns to the main program.
• Another feature is the use of a water level sensor for detecting whether the pool water level has reached a low level, at which water should be added. Thus, duringsubroutine720, for accepting sensor inputs and alarms, thewater level sensor224 is checked at720A. If the water level is above the low level, operation returns to the main program. If the pool level is at the low level, thepool fill valve74 is opened, and operation returns to the main program. The pool fill valve can be subsequently closed when the water level sensor probe again makes contact with water. Alternatively, the processor can be programmed to close the valve a predetermined time interval after it is opened, say one hour. Also, the overfill condition can be sensed, and this information triggers closing the fill valve even though the time interval has not yet elapsed.
• Another aspect of the invention is an emergency disconnect switch for the pool/spa, implemented without the need for bringing line voltage to the emergency disconnect switch, but rather using low voltage signals and the intelligence of thespa controller100. The emergency disconnect switch when closed will cause a grounding resistor to be connected between the earth ground line and line voltage, inducing a ground fault which will be detected by theGFCI62, thus providing a level of redundancy.
• This feature is illustrated inFIG. 16. Theemergency disconnect switch350 is on ahousing352, which is mounted near the spa, to be accessible in the event of a need to immediately shut down the pool/spa equipment powered by line voltage through thesystem100.Conductor wires354,356 run between thecircuit board250 of thecontroller system100 and respective terminals of the normallyopen switch350. Thewire354 is connected to one terminal of thecoil358A of arelay358 on thecircuit board250; the other terminal of the relay coil is connected to a 15V supply. Therelay switch358B is connected between earth ground and through a 10 Kohm resistor362 to one phase of the line voltage service, e.g. the black 120 VAC line, atnode368. The other terminal of theswitch350 is connected to wire356, which is connected tonode362 at theboard250. A 50 Kohm resistor is mounted in thehousing352 between thewires354 and356, and in parallel with theswitch350. A 10 Kohm resistor366 is connected fromnode362 to ground, forming a voltage divider with theresistor360. An analog-to-digital converter (ADC)364 is also connected tonode362 on thecircuit board250, and provides a digital voltage value to thesystem controller402 mounted on theboard250.
• The closing of theemergency stop switch350 will close therelay switch358B, connecting the 120VAC black line voltage atnode368 throughresistor362 to earth ground. This is a ground fault, which is detected byGFCI circuit62, and which is tripped, interrupting line voltage service to the pool controller andpower distribution system100. Thus, all power tosystem100 will be interrupted. As a redundant power disconnect feature, the voltage at thevoltage divider node362 is monitored through theADC364 by thecontroller402 under normal operating conditions. If theswitch350 is closed, theresistor360 is bypassed, and the voltage atnode362 read by the ADC changes. Thecontroller402 detects this condition, and immediately opens the relays providing line voltage to all line voltage loads. Thus, even if theGFCI62 were to fail, and therefore not interrupt line voltage service tosystem100, thecontroller402 would take action to open shut down the line voltage loads.
• Thecontroller402 can also detect that theemergency disconnect switch350 is not properly installed. In thiscase node362 will be at an open circuit voltage condition. Thecontroller402 monitors the voltage atnode362, and if an open condition is detected, this is recognized as an error or fault condition. The controller can then prevent operation of thesystem100, prevent line voltage from being connected to the line voltage loads, or take other action needed to address the lack of proper connection of the stop switch, such as providing an error message on the control panel display.
• FIG. 14D illustrates the “ESTOP disconnect” subroutine722 (FIG. 15) in further detail, wherein theemergency stop switch350 is monitored. At722A, a check is made to determine whether this feature is enabled, and if not, operation returns to the main program (722G). If the feature is enabled, then themicroprocessor402 reads the voltage atnode362 through theADC364. If a value indicating the presence of the switch andresistor360 is not read, an error message is displayed on the control panel (722C) and operation returns to the main program. If the microprocessor senses that the emergency switch system is installed, then atstep722E, if the voltage atnode362 indicates that theswitch350 is closed, then all line voltage loads and features are shut down (722F), and thecontroller100 will wait for power off and reset. If theswitch350 is not closed, operation returns to the main program (722G).
• When the pool filter becomes clogged, the filter pressure rises. As shown inFIG. 1, filter pressure sensors208A and208B are mounted in the filter inlet andoutlet lines9 and10 to monitor the back pressure, i.e. the difference between the input water pressure and the output water pressure, and when it reaches a certain level, the controller causes a warning or error signal to be displayed on the control panel, such as “Back Flush the Filter” or “Clean Filter.”
• Another aspect of this invention is the monitoring of the natural gas supply pressure to the pool heater system. Agas pressure sensor224 is placed in the gas line to thepool heater78 to monitor gas pressure. The sensor includes a sending unit which provides a gas pressure signal. Pressure sensors suitable for the purpose are commercially available; one exemplary sensor is marketed by Omega Engineering Inc., Stamford, CT, as the 30 PSI sensor device, PX182-030-GI. This signal is provided to thecontroller402, which is programmed to provide an error message on the display ofcontrol panel102 when pressure reaches a minimum threshold, and also prevents the heater from operating.
• The gas pressure and backpressure monitoring features are further illustrated in the flow diagram ofFIG. 14E. The subroutine720 (“accept input and alarms”) further includesstep720C, wherein the microprocessor receives as data inputs the gas pressure value, the input water pressure (IP) to the filter, and the output water pressure (OP) from the filter. Atstep720D, if the gas pressure is below the predetermined low threshold value, the heater is disabled and an error message is sent to the panel display (720E). If the filter backpressure (i.e., the difference between the input pressure and the output pressure) exceeds a predetermined threshold value (720F), an alert message is sent to the panel display to indicate that the filter should be cleaned (722N).
• FIG. 14F illustrates additional steps which can be included in the “accept inputs and alarms”subroutine720.Sensors218 and216 respectively detect the condition that the pool cover is open or the gate to the pool area is open. The sensors can be Hall effect switches, or other types of switching devices, as will be apparent to those skilled in the art. The sensor outputs are connected to thecontroller402, which is programmed to interpret the outputs as potential alarm conditions, and generates an audible warning signal using alarm sound speaker or siren96 (FIG. 6) or another warning signal such as a visible message on a panel display, indicating that the pool gate or cover is open. Thus, at step720I, the subroutine checks to see whether an alarm signal has been input from a sensor such as the gateopen sensor218 or thepool cover alarm224. If not, operation returns to the main program (or to other aspects of this subroutine). If an alarm has been received, then an alarm output is activated by thecontroller402, which can initiate an audible and/or visible warning message.
• An improvement in production is obtained by use of an in-circuit-programmable microcontroller. This microcomputer can be programmed by sending suitable signals to an appropriately configured input circuit after the microcomputer has been installed via solder connections onto thecircuit board250. This improved production technique includes the steps of (i) soldering the microcomputer into a circuit board configured for in-circuit programming; (ii) connecting the board to a programmer device using electrical leads, in accordance with the manufacturer's instructions; (iii) loading the program into the microcomputer from the programmer; (iv) power up the circuit board in accordance with normal operating procedures; and (v) verify the proper functioning of the circuit board with the microcomputer. Operation is verified in this embodiment by powering up the board and performing an operational clock, either manually or by a suitable computer test system.
• Temperature sensors that are known in the art utilize a single thermistor sealed inside a case for sensing water temperature, high limit temperatures in a heater, and air temperatures. To facilitate redundancy in these critical components, two thermistors are installed inside one housing. This moderate increase in cost doubles the reliability of a very reliable technology, and removes the need for a more expensive option of dual sensor assemblies dedicated to a single temperature value.
• FIGS. 17-19 illustratetemperature sensor202 in further detail.Temperature sensors204 and206 can have the same circuitry and structure assensor202, and so will not be described further.FIG. 17 is a circuit diagram of thesensor202, which includes two solid statetemperature sensing devices202B,202C, one terminal of each connected towiring202A atnode202D. The solid state temperature sensing devices can be implemented by various devices, including thermistors, thermocouples, temperature-sensing diodes wherein leakage currents are temperature-dependent, or constant current source circuits wherein the current is temperature-dependent. An end of thewiring202A is connected to thecontroller circuit board250 atconnector410. Thewiring202A is connected to a +5VDC supply node412. The second terminal ofthermistor202B is connected by wiring202E, through the connector412 to one terminal ofresistor414, connected to ground. The second terminal ofthermistor202C is connected by wiring202F toresistor416, also connected to ground. Theresistors202B and414 thus form a voltage divider circuit, with the voltage atnode420 dependent on the variable resistance of the thermistor. Similarly,resistors202C and416 provide a voltage divider circuit, with the voltage atnode418 dependent on the variable resistance of the thermistor. The voltages atnodes418 and420 are converted to digital values byADC364 and monitored by thecontroller402. Since the resistance values of the thermistors vary precisely with their temperatures, two temperature readings are provided by thesensor202. The temperature values can be averaged, and in the event of anomalous readings from one or the other thermistor, the anomalous value can be discarded. This temperature sensor provides improved reliability through this redundancy.
• An improved assembly technique is also used in the fabrication of thesensor202. Referring now toFIGS. 19 and 19, the sensor includes a dielectric substrate or circuit board202G. Adistal end202H of the substrate has two notches202I,202J formed therein. Therespective thermistors202B,202C are supported in the notches of the board.FIG. 18 is a diagrammatic view showing one side of the board202G;FIG. 19 shows the reverse side of the board.
• Thesensor202 further includes a metal tubular housing202K having a closed end202L and anopen end202M. Acollared sleeve202N is used, in combination with the length of the sensor circuit board202G, to precisely control the depth of insertion of the circuit board into the housing prior to potting with an epoxy. This eliminates the problem of imprecise circuit board placement, which can lead to disparities in sensed temperatures between sensor units. Thesleeve202N has an opening formed therein through which the wiring leads202A,202E and202F are brought out. In this embodiment, the sleeve is a plastic molded part with a distal end which contacts the circuit board202G, and a collar202O is larger in diameter than the diameter of the housing202K, thus providing a stop surface against which the open end of the housing is brought into contact during assembly. Of course, other arrangements could alternatively be employed to provide a circuit arrangement which is self-registering in insertion depth within the housing. The self-registering feature of the temperature sensor can alternatively be employed with sensors using a single sensing element, such as a single thermistor.
• FIGS. 20A-20C illustrate an exemplary circuit schematic for thecircuit board250. Various sensor inputs to the controller are passed through signal conditioning circuitry and then to the ADC364 (FIG. 20A). Thus, for example,air temperature sensor202 is shown as a two wire device, e.g. with a single thermistor sensor, connected to the signal conditioning circuitry indicated as203, although it is contemplated that an improved sensor as shown inFIGS. 17-19 will alternatively be employed. The improved sensor will utilize two multiplexed inputs to the ADC, so that each circuit can be read by thecontroller402. The output of the signal conditioning circuitry is passed to theADC364, which can process several inputs through a multiplexing arrangement.Illustrative sensor devices204,206,210,212 are similarly connected through signal conditioning circuitry to the ADC. Other sensor devices, e.g. thegate sensor218, may have signal levels at appropriate logic levels, and so may not require the same signal conditioning in order for the ADC to have a desired signal level to convert to digital form. Circuitry for interfacing sensor devices to a microcomputer through an ADC are well known in the microprocessor arts.
• A crystaloscillator clock circuit320 provides clock signals for the microcomputer.
• Thecircuit board assembly250 also includes a power supply322 (FIG. 20A), which converts the line voltage service into 24 VAC for providing power to the water valves, and into 15 VDC, 12 VDC and 5 VDC for providing DC power needs of the controller board assembly, such as relay power and a regulated DC supply for themicrocomputer402.
• Themicroprocessor402 controls the line voltage loads and low voltage loads throughoutput drivers320 and322, which in this exemplary embodiment are Darlington drivers which convert the logic level output signals from the microprocessor into the necessary drive signals for controlling the relays and switches which operate the line voltage loads and the low voltage loads, such as the valves. Exemplary circuitry is illustrated for operating exemplary line voltage loads, including the heater78 (FIG. 20C) and pump80 (FIG. 20B). Exemplary circuitry is further illustrated for operating the low voltage loads, e.g. the fill valve76 (FIG. 20B), and valve74 (FIG. 20C). In this embodiment, thelighting circuits90A and90B are controlled through triac switches. Exemplary circuitry is illustrated for operatinglighting circuit90B, by use oftriac circuit306 which is in turn driven by the driver332 (FIG. 20C).
• Aset402A of wiring connections running to programming pins of themicrocomputer402 is made available for connection to the programmer device used for in-circuit programming as described above.
• Themicroprocessor402 further interfaces with thecontrol panels102,104 and112 through an interface338 andsupport circuit336. The interface supplies panel power at 5 VDC, and power at 12 VDC and 24 VAC for panel lighting functions. Data output, data input and clock signals are provided onlines342,344 and346, respectively. The interface provides three separate connector interfaces, one connector for each panel, so that the panels are connected to the circuit board assembly through respective detachable connector devices.
• It is understood that the above-described embodiments are merely illustrative of the possible specific embodiments which may represent principles of the present invention. Other arrangements may readily be devised in accordance with these principles by those skilled in the art without departing from the scope and spirit of the invention.

Claims (10)

1-53. (canceled)

54. A bathing installation control system, comprising:

a plurality of electrically powered devices associated with operation of the bathing installation;

a microprocessor-based controller system operatively connected to the plurality of electrically powered devices for controlling the operation of said devices;

a ground fault circuit interrupter (GFCI) circuit;

a line voltage service connected to the controller system and the plurality of electrically powered devices through the GFCI circuit, the GFCI circuit adapted to detect ground faults and interrupt the line voltage service to the controller system and the plurality of electrically powered devices upon detection of a ground fault;

a fault inducing circuit for selectively inducing a ground fault condition between line voltage and ground in response to an electronic command signal;

a circuit actuation system responsive to an error or fault condition, the test circuit actuation system connected to said controller and said fault inducing circuit, the circuit actuation system adapted to actuate the fault inducing circuit to induce a ground fault between line voltage and ground in response to the error or fault condition, thereby tripping the GFCI circuit and disconnecting the line voltage service from said plurality of electrically powered devices and said controller system.

55. The system ofclaim 54, wherein the circuit actuation system includes a manually operated switch accessible to a user of the bathing installation.

56. The system ofclaim 55, wherein the error or fault condition includes the condition that the circuit actuation system is not properly installed in said system.

57. The system ofclaim 54, further comprising a plurality of switches each for selectively connecting one of said plurality of devices to said line voltage, the plurality of switches controlled by said controller system, and wherein the controller system is responsive to the circuit actuation system to command said plurality of switches to disconnect the plurality of devices from said line voltage in the event the circuit actuation system actuates the fault inducing circuit and said GFCI circuit fails to disconnect said line voltage service from said controller system and said plurality of devices.

58. The system ofclaim 57, wherein said plurality of switches each comprises a relay switch.

59. The system ofclaim 54, wherein the circuit actuation system includes an algorithm performed by said microprocessor-based controller system and adapted to cause the controller system to generate said electronic command signal in response to an algorithmically-determined fault or error condition.

60. The system ofclaim 59, wherein said algorithmically-determined fault or error condition includes a decision to conduct a GFCI circuit test.

61. The system ofclaim 54, wherein the bathing installation is a pool or spa installation.

62. The system ofclaim 54, wherein the plurality of electrically powered devices includes a water pump for circulating bathing water through a circulating water path, and a bathing water heater.

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