Abstract:
A method for sequentially monitoring a level of a sanitation agent comprises the step of providing a supply tube having a first portion and a second portion. The method includes the step of linking the supply tube first portion and the supply tube second portion with a pipe. An optical sensor is situated adjacent the pipe, and is used to take a reference reading and a fault check reading. A controller imposes a warning signal when a difference between the reference reading and the fault check reading is greater than a threshold. The reference reading is taken when the sanitation agent is in direct contact with the pipe.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 13/969,348 filed Aug. 16, 2013, which claims priority to U.S. Provisional Patent Application No. 61/683,876 filed Aug. 16, 2012. The disclosure of each is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates generally to the field of alarm units for dishwashers. More specifically, the invention relates to the field of alarm units that monitor the amount of sanitation agents in dishwashing systems. 
     SUMMARY 
     Systems and methods for monitoring sanitation agents in dishwashing systems are disclosed herein. According to an embodiment, an alarm system for monitoring a level of a sanitation agent in a dishwasher having a sanitation agent supply vessel associated with a supply tube comprises a hollow pipe. The supply tube has a first portion adjacent the supply vessel and a second portion. The supply tube first portion conveys the sanitation agent to the supply tube second portion via the hollow pipe. The alarm system includes an optical sensor configured for sequentially taking a reference reading, a first reading, and a second reading. The first and the second readings are averaged to compute a fault check reading. The alarm system includes a first output device, and a controller in electronic communication with the optical sensor and the first output device. The controller causes the first output device to output a warning signal upon detecting an air bubble in the pipe when a magnitude of the difference between the reference reading and the fault check reading exceeds a threshold. 
     According to another embodiment, a method for monitoring a level of a sanitation agent in a dishwashing system having a sanitation agent supply vessel includes the step of providing a supply tube having a first portion and a second portion. The supply tube first and second portions are unconnected to one another. The supply tube first portion and second portion are linked with a pipe. An optical sensor is situated adjacent the pipe, and a reference reading, a first reading, and a second reading is sequentially taken with the optical sensor. The first reading and the second reading is averaged to form a fault check reading. The method further includes the step of imposing a warning signal by a controller when a magnitude of the difference between the reference reading and the fault check reading exceeds a threshold. The warning signal includes at least one item selected from the group consisting of a flashing light and an audible alarm. 
     According to yet another embodiment, a method for sequentially monitoring a level of a sanitation agent comprises the step of providing a supply tube having a first portion and a second portion. The method includes the step of linking the supply tube first portion and the supply tube second portion with a pipe. An optical sensor is situated adjacent the pipe, and is used to take a reference reading and a fault check reading. A controller imposes a warning signal when a difference between the reference reading and the fault check reading is greater than a threshold. The reference reading is taken when the sanitation agent is in direct contact with the pipe. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       Illustrative embodiments of the present invention are described in detail below with reference to the attached drawing figures and wherein: 
         FIG. 1  is a perspective view of a PRIOR ART dishwashing system; 
         FIG. 2  is a perspective view of an alarm unit according to an embodiment of the present invention; 
         FIG. 3  is a perspective view of the alarm unit of  FIG. 2  with a front side of a case removed; 
         FIG. 4  is a schematic illustrating electronic communication between various components of the alarm unit of  FIG. 2 ; 
         FIG. 5A  is a perspective view of the dishwashing system of  FIG. 1  after a portion of a tube has been cut out to allow the alarm system  200  of  FIG. 2  to be operatively coupled to the dishwashing system; 
         FIG. 5B  is a perspective view of the alarm unit of  FIG. 2  after it is operatively coupled to the dishwashing system of  FIG. 5A ; 
         FIG. 6  is a flowchart illustrating a method performed by the alarm unit of  FIG. 2 ; 
         FIG. 7  is a perspective view of an alternate embodiment of the alarm unit of  FIG. 2 ; and 
         FIG. 8  is a schematic illustrating a software for use with the alarm unit of  FIG. 7 . 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the present invention provide systems and methods for monitoring sanitation agents in dishwashing systems. Dishwashing systems provide a convenient and efficient alternative to washing dirty dishes by hand and are particularly ubiquitous in commercial settings (e.g., restaurants, bars, hotels, et cetera), where a large number of dirty dishes must be cleaned and sanitized on a regular basis. 
     Generally speaking, commercial dishwashers clean and sanitize dirty dishes placed therein as follows. The dirty dishes are first “prewashed”, i.e., flushed with cold or warm water under moderate pressure to remove food particles. The dishes are then cleaned or washed with a cleaning compound (e.g., by soaking the dishes in the cleaning compound, by spraying the dishes with the cleaning compound, by foaming or jelling, et cetera). After the cleaning process, the dishes are rinsed with clean potable water to remove substantially all traces of the cleaning compound. Finally, the dishes are sanitized to destroy any organisms which may be present on the dishes after the cleaning and rinsing cycles. 
     The sanitation process is key to the effective operation of dishwashing systems, as it prevents disease, spoilage of foods, interference of microorganisms, et cetera. Commercial dishwashing systems generally utilize either high temperatures or sanitation agents to sanitize the dishes. Using high temperatures (i.e., hot water or steam) to sanitize the dishes has its advantages, as water is generally inexpensive, nontoxic and readily available. However, some organisms may remain alive on the dishes even after being subjected to hours of boiling temperatures. Furthermore, sanitation by high temperatures may be somewhat inefficient, as dishes generally have to be immersed in hot water or treated with steam for at least fifteen minutes to effectuate proper sanitation. Additionally, dishwashing systems that use high temperatures for their sanitation cycles are generally more expensive to purchase and require more energy than dishwashers utilizing sanitation agents. 
     Low temperature dishwashing systems (i.e., dishwashers that use sanitation agents for sanitation), hence, are becoming increasingly popular. These dishwashing systems may employ a chlorine solution as the sanitation agent, as chlorine is effective against a wide variety of microorganisms, is not affected by water hardness, is non-staining, non-film forming, and generally inexpensive. Alternatively, iodophors (i.e., loosely bound complexes of iodine and non-ionic surface active agents) and quaternary ammonium compounds may be used as sanitation agents in low temperature dishwashing systems. 
     Technological advancements have improved the efficiency and durability of low temperature dishwashers. Low temperature dishwashing systems have a large drawback, however: the sanitation agent may run out without anyone&#39;s knowledge, leading to the use of unsanitary dishes that look clean to the naked eye. 
     Many prior art alarm systems, utilizing vacuum sensors, probes, and/or impedance sensors have been developed and marketed to address this issue, though with little or no success. For example, alarm systems using vacuum sensors have proven to be unsatisfactory because they are prone to giving false alerts, and alarm systems utilizing probes have proven to be ineffective because the probes corrode quickly and require continual replacement. Similarly, alarm units using impedance sensors generally work only for a specific solution and do not allow for other types of sanitation agents and brands from being used. The present invention is directed to an alarm unit that can effectively be used with different types and brands of sanitation agents and low temperature dishwashing systems, to apprise users that the respective sanitation agent has run out and needs to be replenished or that undesirable air bubbles are present. 
     Attention is now directed to  FIG. 1 , which shows an exemplary prior art commercial dishwashing system  100 . The dishwashing system  100  may have a housing  102 H having a front side  102 F, a right side  102 R, and a top side  102 T. While not clearly visible in the figures, the housing  102 H of the dishwashing system  100  may also have a left side  102 L opposite the right side  102 R and a back side  102 B opposite the front side  102 F. 
     The housing  102 H may have at the front side  102 F a handle  104  secured to a door  106 . The handle  104  may be used to pull the door  106  open to reveal one or more dish racks, which may be filled with dirty dishes that need to be cleaned. The dishwashing system  100  may also have one or more inputs  108  (e.g., knobs, push buttons, et cetera) for allowing users to control the various settings of the dish washing system  100 , such as cycle duration, temperature, et cetera, and outputs  110  (e.g., lights, cycle alarms, et cetera) to convey information about the workings of the dishwashing system  100  to the users. 
     A sanitation agent supply vessel  112  (a bucket, box, et cetera) may be adhered to the dishwashing system  100  on the right side  102 R of the housing  102 H. The supply vessel  112  may be configured to retain a sanitation agent  114 , and may dispense the sanitation agent  114  during the sanitation cycles via a supply tube  116 . The supply tube  116  may be made of plastic or other desirable materials, and may have a proximal end  116 P which may be coupled to (or be adjacent or otherwise associated with) the supply vessel  112  and a distal end  116 D which may terminate at an inside of the housing  102 H (e.g., through the back side  102 B). While the sanitation agent supply vessel  112  is shown in the figures as being on the right side  102 R, people of skill in the art will appreciate that the supply vessel  112  could be adhered to any location on the housing  102 H of dishwashing system  100  (e.g., the top side  102 T, the left side  102 L, et cetera). Further, in some commercial dishwashers, the supply vessel  112  may be detached from the housing  102 H, or may be internal to the housing  102 H. The alarm system disclosed herein may be used with each of these (and any other) types of low temperature dishwashing systems, so long as they utilize a supply tube  116  to furnish the sanitation agent  114  from the supply vessel  112  to the dishes. 
     Attention is directed now to  FIG. 2 , which shows an alarm system  200  according to one embodiment of the present invention. The alarm system  200  may have a case or housing  202 C comprising plastic, metal, metal alloys, or other desirable materials. The case  202 C may have a top side  202 T, a right side  202 R, and a front side  202 F. While not clearly shown in the figures, the case  202 C may also have a left side  202 L opposite the right side  202 R, a back side  202 B opposite the front side  202 F, and a bottom side  202 M opposite the top side  202 T. 
     A generally hollow pipe  204  having a first end  204 A and a second end  204 B may extend through the case  202 C such that the first and second pipe ends  204 A,  204 B are outside the case  202 C and adjacent the case left side  202 L and right side  202 R, respectively. The pipe  204  may be made of clear glass or other desirable materials. People of skill in the art will appreciate that while the pipe  204  is shown in the figures as extending through the case left side  202 L and the right side  202 R, the pipe  204  may similarly extend through the case top side  202 T and the bottom side  202 B. Further, while the first and second pipe ends  204 A and  204 B are shown in the figures as extending past the case left side  202 L and the case right side  202 R, respectively, the pipe ends  204 A,  204 B may also be inset with respect to or be flush with the case  202 C. In other embodiments still, the first end  204 A of the pipe  204  may extend into the case  202 C through one side (e.g., the left side  202 L, the top side  202 T, the right side  202 R, et cetera) and the second end  204 B of the pipe  204  may extend out of the case  202 C through the same side; in these embodiments, the pipe  204  may extend at least partway into the case  202 C. 
     A first output device  206  and a second output device  208  may be located on the case front side  202 F. The first output device  206  and the second output device  208  may each be, for example, a light emitting diode or another kind of illuminating device, and may for example be green and red in color, respectively. People of skill in the art will appreciate that the placement, number, and color of the first and second output devices  206 ,  208  is exemplary only, and that the alarm system  200  may include multiple devices (e.g., lights) of varying (or the same) colors and/or other output devices (e.g., gauges, meters, electronic display screens, et cetera). The case  202 C may include a third output device  210 , which may be, for example, an alarm speaker. Speaker holes  210   h  for the speaker  210  may be provided on the case top side  202 T, or at another surface of the case  202 C (e.g., the case right side or left side  202 R,  202 L, et cetera). 
     The case top side  202 T may also include a first input device  212 , which may be, for example, a button  212  as shown or another input device (e.g., a switch, knob, biometric sensor, et cetera). The first input device  212  may be used (e.g., pressed) to silence the third output device (i.e., the alarm speaker)  210 , as discussed in further detail below. 
     The alarm system  200  may be powered by standard AC power (e.g., at 120 volts, 240 volts, et cetera) using an AC adapter  214 . Some embodiments of the alarm system  200  may be configured to be powered by a lower voltage (e.g., 12 volts, 5 volts, et cetera) to conserve energy during use, and in these embodiments, a step down transformer may be associated with the AC adapter  214  to step down the voltage from the standard voltage to the lower operating voltage. In other embodiments, the AC adapter  214  may be omitted and the system  200  may be powered by DC power instead (e.g., by using lithium ion or other batteries, which may for example be rechargeable). Embodiments of the alarm system  200  that may be powered by either AC power or DC power are also contemplated. 
     Attention is now directed to  FIG. 3 , which shows the alarm system  200  without the case front side  202 F. As can be seen, an optical sensor  216  may be enclosed within the case  202 . The optical sensor  216  may comprise a photo-resistor, a photodiode, a phototransistor, et cetera. And while not clearly shown in the figures, the optical sensor  216  may include an energy emitting portion  216 E and an energy sensing portion  216 S. The optical sensor  216  may be programmable, and the energy sensing portion  216 S may be configured to measure light energy emitted by the emitting portion  216 E after the light energy is reflected off a surface. 
     A circuit board (e.g., a single or dual layer printed circuit board)  220  may be located adjacent the optical sensor  216 , or at another location within the case  202 . The contents of the circuit board  220  are shown in  FIG. 4 . The circuit board  220  may include a processor (or controller)  222  that is in data communication with a storage unit  224  (located on a microchip on the circuit board  220 , for example). The storage unit  224  may comprise volatile memory (e.g., random access memory such as DRAM, SRAM, SDRAM, FLASH, EEPROM, et cetera) and non-volatile memory (e.g., ROM, hard drive memory, et cetera), and may be configured for storage of a program  226  that embodies and causes to be executed the steps outlined herein. Each of the first output device  206 , the second output device  208 , the third output device  210 , the first input device  212 , the low voltage adapter  214  and the optical sensor  216  may be in electronic communication with the processor  222 . 
       FIGS. 5A-5B  show the alarm system  200  being operatively coupled to the dishwashing system  100  (and specifically, the supply tube  116 ). To operatively couple the alarm system  200  to the dishwashing system  100 , a part of the sanitation agent supply vessel tube  116  may first be cut out (or the tube  116  may simply be cut) to divide the supply tube  116  into a first portion  118  having an end  118 A and a second portion  120  having an end  120 A that faces the first portion end  118 A (see  FIG. 5A ). Or, of course, two independent tubes may be provided (e.g., along with the alarm system  200 ) to function as portions  118 ,  120 . Then, as shown in  FIG. 5B , the supply tube first portion end  118 A may be placed within (or adjacent) the hollow pipe end  204 A of the alarm system  200 , and the supply tube second portion end  120 A may be placed within (or adjacent) the hollow pipe end  204 B (see  FIG. 5B ). The sanitation agent  114 , thus, may travel from the supply vessel  112  through the tube first portion  118  to the pipe  204 , and then through the pipe  204  to the tube second portion  120  (and thereafter to the dishes, as configured by the manufacturer of the dishwashing system  100 ). It will be appreciated that this arrangement may not alter or impede in any significant way the workings of the dishwashing system  100 , as the sanitation agent  114  simply flows through the hollow pipe  204  but does not come into contact with any other component of the alarm system  200 . If desired, fittings or seals may used to ensure that the tube first and second portion ends  118 A,  120 A form a leak-proof pathway with the pipe  204  without substantially impeding the flow of the sanitation agent  114 . Further, in some embodiments, the tube  116  may be passed through the glass pipe  204  intact (i.e., with the pipe overlaying the continuous tube  116 ). 
     Attention is directed now to  FIG. 6 , which illustrates a method  300  effectuated by the processor  222  (via, for example, execution of the program  226 ). The method  300  may begin at step  302 , and at step  304 , a user wishing to utilize the dishwashing system  100  to clean and sanitize dishes may power the dishwashing system  100 . At step  306 , the user may plug the AC adapter  214  into a power source to power the alarm system  200 . If the alarm system  200  uses DC power (e.g., batteries), the user may plug the batteries in (or, for example, set an on/off switch to an “on” position) to power the alarm system  200 . People of skill in the art will appreciate that while the alarm system  200  is being illustrated in  FIG. 6  as being powered after the dishwashing system  100  is powered, that the alarm system  200  may in fact be powered at any appropriate time (e.g., before the dishwashing system  100  is powered). 
     Upon being powered, the processor  222  of the alarm system  200  may cause the program  226  to be executed at step  308 . At step  310 , the processor  222  may cause the first output device  206  to illuminate. As discussed above, the first output device  206  may be, for example, a green colored light, and may serve to apprise the user that the system  200  is powered on. 
     At step  312 , after the sanitation agent  114  has begun to travel through the pipe  204  via the tube first portion  118 , the processor  222  may cause the optical sensor  216  to take a reference reading (or measurement)  228 . Specifically, the processor  222  may cause the energy emitting portion  216 E of the optical sensor  216  to emit light energy and cause the energy sensing portion  216 S of the optical sensor  216  to measure the same after this light energy has reflected off the sanitation agent  114  within the clear glass pipe  204 . When taking the reference reading  228 , the processor  222  may assume that the reserve of the sanitation agent  114  in the sanitation agent supply vessel  112  has not depleted and that the supply tube  116  and pipe  204  are supplying the sanitation agent  114  to the dishwashing system  200 . In some embodiments, the program  226  may incorporate a waiting time (i.e., wait for a certain time period after the alarm system  200  is plugged in before taking the reference reading  228 ) to ensure that the reference reading  228  is being taken during the sanitation cycle of the dishwashing system  100 . The processor  222  may then cause the reference reading  228  to be stored in the storage unit  224  at step  314 . 
     At step  316 , the processor  222  may cause the optical sensor  216  to take a “fault check” reading  229  and store the fault check reading  229  in the storage unit  224 . At step  318 , the processor  222  may compare the reference reading  228  with the fault check reading  229 . Specifically, the processor  228  may ascertain the magnitude of the difference between the reference reading  228  and the fault check reading  229 . At step  320 , the processor  222  may check whether this magnitude of the difference between the reference reading  228  and the fault check reading  229  is less than a predefined threshold  230 . If the magnitude of the difference between the reference reading  228  and the fault check reading  229  is less than the predefined threshold  230 , the processor  222  may assume that the pipe  204  continues to have the sanitation agent  114  in it and infer therefrom that the sanitation agent supply vessel  112  is not empty. That is, where the magnitude of the difference between the reference reading  228  and the fault check reading  229  is less than the predefined threshold  230 , the processor  222  may determine that both the reference and the fault check readings  228 ,  229  incorporate light energy reflected off the sanitation agent  114  within the pipe  204 . The processor  222  may then wait a first time unit  232 , which may be for example, a tenth of a second, a second, a minute, et cetera, and return to step  316  to take a new fault check reading  229  for comparison with the reference reading  228 . 
     If, however, the processor  222  determines at step  320  that the magnitude of the difference between the reference reading  228  and the fault check reading  229  is greater than (and in some embodiments, equal to) the predefined threshold  230 , the processor  222  may assume that the fault check reading  229  incorporates light energy that has reflected off an air bubble  231  within the pipe  214 , which in turn has caused the magnitude of the difference between the two readings to exceed the threshold  230 . The air bubble  231  in the pipe  114  may indicate that the supply vessel  112  has (or is about to) run out of the sanitation agent  114 . Alternatively, the air bubble  231  may have simply been a byproduct of the flow of the sanitation agent  114  within the pipe  214  in line with the commands of the dishwashing system  100 . 
     It has been found that the air bubble  231  formed upon depletion of the sanitation agent  114  will generally be longer than the air bubble  231  formed within the pipe  214  during normal operation (i.e., where the sanitation agent supply vessel  112  is not depleted). Therefore, to ensure that the air bubble  231  was created because of the depletion of the sanitation agent  114 , the processor  222  may wait a second time unit  236  (e.g., a microsecond, a milli-second, et cetera) before taking a fault confirmation reading  234  with the optical sensor  216  at step  324 . If the magnitude of the difference between the reference reading  228  and the fault confirmation reading  234  is less than the predefined threshold, the processor  222  may assume that the fault check reading  229  incorporated light energy reflected off the air bubble  231  that was formed during normal operation of the dishwashing system  100  and return to step  316  to take additional fault check readings  229 . If, on the other hand, the processor determines at step  326  that the magnitude of the difference between the reference reading  228  and the fault check reading  229  continues to exceed the threshold  230 , the processor  222  may assume that the air bubble  231  was formed upon depletion of the sanitation agent  114 . The processor  222  may therefore output a warning signal  238  at step  328 . 
     The warning signal  238  may be of various types. In one embodiment, the warning signal  238  may comprise the flashing of both the first and second output devices  206 ,  208  (i.e., the green and red lights), and the sounding of an alarm via the third output device  210  (i.e., the alarm speaker  210 ). Where the alarm system  200  is being used in a setting where the sound from the speaker  210  is undesirable, the warning signal  238  may include only the flashing of the first and second output devices  206 ,  208 . Further, the user may utilize the first input device  212  (e.g., a button) to silence the audible alarm. In some embodiments, the user may use the first input device  212  to silence the audible alarm only for a period of time (e.g., three minutes, five minutes, et cetera) to allow the user to refill the sanitation agent supply vessel  112 . 
     The processor  222  may then at step  330  take a post-fault confirmation reading  240 , and compare the post-fault confirmation reading  240  with the reference reading  228  at step  332 . If the magnitude of the difference between the post-fault confirmation reading  240  and the reference reading  228  is less than the predefined threshold  230 , the processor  222  may assume that the sanitation agent  114  in the sanitation agent supply vessel  112  has been replenished and terminate the warning signal  238  at step  334 . The program  116  may then loop back to step  322 , where it may wait the first time unit  232  and then take another fault check reading  229  at step  316 . If, on the other hand, the magnitude of the difference between the post-fault confirmation reading  240  and the reference reading  228  is greater than the predefined threshold  230 , the program  226  may assume that the supply vessel  112  continues to have an insufficient quantity of the sanitation agent  114  and return to step  330  to take another post-fault confirmation reading  240 . The program  226  may continue in this fashion, and end when the user powers down the system  200  (e.g., by disconnecting the adapter  214 ). 
     Thus, as has been described, the alarm system  200  may utilize the optical sensor  216  to determine if an air bubble  231  has been formed within the pipe  204 , distinguish between relatively insignificant air bubbles  231  that are formed during normal operation of the dishwashing system  100  and larger air bubbles  231  that are formed upon depletion of the sanitation agent  114 , and warn the user when the sanitation agent  114  needs to be replenished without interfering with the workings of the dishwashing system  100 . Further, because the reference reading  228  (and the remaining readings such as the fault check reading  234 , the fault confirmation reading  234 , et cetera) are taken anew each time the alarm system  200  is powered on, users may use the alarm system  200  to monitor different types of sanitation agents. 
     Advantageously, various types of existing low temperature dishwashing systems may be easily and conveniently retrofitted to incorporate the alarm system  200 . Of course, the alarm system  200  may also be provided as part of new dishwashing systems. Various types of fasteners (e.g., hooks, Velcro®, nuts and bolts, et cetera) may be used to situate the alarm system  200  at a desirable location (e.g., above or behind the dishwashing system  100 , on a surface of a dishwashing machine control box, et cetera). 
     In some embodiments, instead of successively comparing each of the fault check reading  229  and the fault confirmation reading  234  with the reference reading  228  in the method  300 , the processor  222  may first compare the fault check reading  229  with the reference reading  228  to ensure that the magnitude of their difference is less than the threshold  230 , and then compare the fault check reading  229  with the fault confirmation reading  234  (instead of comparing the fault confirmation reading  234  with the reference reading  228 ). In these embodiments, the warning signal  238  may be outputted if a magnitude of a difference between the fault check reading  239  and the fault confirmation reading  234  exceeds a second threshold  230 A (which may be of a different numerical value than the threshold  230 ). People of skill in the art will appreciate that a difference between the magnitudes of the fault check reading  239  and the fault confirmation reading  234  in excess of the second threshold  230 A may indicate that the fault confirmation reading  234  incorporates light energy that has reflected off the air bubble  231 , which may in turn indicate that the supply vessel  112  needs to be replenished with the sanitation agent  114 . 
     In other embodiments still, the fault check reading  229  may be representative of several readings taken with the optical sensor  216 . For example, in some embodiments, instead of comparing the reference reading  228  with an isolated fault check reading  229  at steps  318  and  320 , and then with an isolated fault confirmation reading  234  at steps  324  and  326 , the program  226  may instead first cause several sequential fault check readings  229  to be taken and averaged, and then compare this averaged fault check reading  229  with the reference reading at steps  318  and  320 . The average value of the various fault check reading  229  may be determined using any appropriate technique, such as a root mean square, a weighted mean, et cetera. In these embodiments, the subsequent comparison between the fault confirmation reading  234  and the threshold reading  228  may be omitted. The program  226  may also compute other information about the readings, such as the variance of the sequential fault check readings  229 , and store this information in the storage unit  224 . 
     Attention is directed now to  FIG. 7 , which shows an alternate embodiment  400  of the alarm system  200 . For uniformity and brevity, corresponding numbers may be used to indicate corresponding parts, though with any noted deviations. Further, people of skill in the art will appreciate that the alarm system  200  (and hence the alarm system  400 ) may be modified in various ways, such as by incorporating all or part of the disclosures herein. 
     One of the main differences between the alarm system  200  and the alarm system  400  is that the alarm system  400  may include a connection means  402  (e.g., a USB port, an SD or other card reader, a wired or wireless networking port such as a WIFI port a Bluetooth port, et cetera) for allowing the user to change the various settings of the alarm system  400 . The connection means  402  may be in data communication with the processor  222 . The user may electronically couple the alarm system  400  with a computer or other device using the connection means  402 , and then use a software  404  to make changes to the settings of the alarm  400 .  FIG. 8  shows an exemplary interface  406  of the software  404 . As can be seen, the user may use this interface  406  for trouble shooting, to adjust the numerical values of the threshold  230 , the first time unit  232  and the second time unit  236 , to configure the warning signal  238  (e.g., change the volume of the audible alarm or the frequency of the flashing lights), et cetera, based on the type of sanitation agent  114  being employed and other relevant considerations (e.g., dishwasher type and/or manufacturer, and location of the dishwashing system  100 ). The software  404  may also include a database  408  that includes optimal settings for use with particular sanitation agents  114  and/or dishwashing systems  100 . In some embodiments, the user may be allowed to store in the storage unit  224  multiple settings configured for use with varying dishwashing systems  100 ; the user may then apply one of the multiple settings (by pushing a button, for example) depending on the sanitation agent  114  being used, the type and brand of the dishwashing system  100 , the location of the dishwashing system  100 , et cetera. In some embodiments, the interface  406  may include a mute function  260 . Like the first input device  212 , a user may use the mute function  260  to, for example, silence the third output device  210 , which may desirably allow a user to silence the alarm  210  remotely. In some embodiments, the mute function  260  may also allow a user to cancel the audible alarm  210 , or to set a duration for which the alarm  210  is to be muted (e.g., about five minutes). The alarm system  400  may thus provide the user with increased flexibility. 
     Many different arrangements of the various components depicted, as well as components not shown, are possible without departing from the spirit and scope of the present invention. Embodiments of the present invention have been described with the intent to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art that do not depart from its scope. A skilled artisan may develop alternative means of implementing the aforementioned improvements without departing from the scope of the present invention. 
     It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations and are contemplated within the scope of the claims. Not all steps listed in the various figures need be carried out in the specific order described.