Patent Publication Number: US-2018038895-A1

Title: Metering System Tamper Detection

Description:
TECHNICAL FIELD 
     The present invention relates to a metering system and method, and more particularly, to systems and methods for detecting abnormal conditions in a metering device. 
     BACKGROUND 
     Metering systems are subject to tamper events. Tamper events may include anything from bypassing a disconnect switch within a meter to interchanging meters from one consumer location to another. Because metering systems can be tampered with in many ways, there are many ways in which a meter can react. Current metering systems have a variety of tamper detection methods available; however, generally a single tamper sensor results in a single meter response. 
     The foregoing background discussion is intended solely to aid the reader. It is not intended to limit the innovations described herein. Thus, the foregoing discussion should not be taken to indicate that any particular element of a prior system is unsuitable for use with the innovations described herein, nor is it intended to indicate that any element is essential in implementing the innovations described herein. The implementations and application of the innovations described herein are defined by the appended claims. 
     SUMMARY 
     An improved metering system for determining whether a tamper condition is present in a metering device is desired to more effectively determine what corrective actions to carry out. 
     An aspect of the present disclosure provides a metering system comprising a meter socket and a meter. The meter is configured to couple to the meter socket. The meter comprises a memory, a plurality of sensors, and a processor. Each of the plurality of sensors are configured to detect a different condition of the meter. The processor is configured to: determine a plurality of events that have occurred based on the conditions detected by the sensors; compare the plurality of events to a table stored in the memory of the meter, the table defining an action to be performed by the meter for each of a plurality of different combinations of the plurality of events; select an action from the table for which the plurality of events match a corresponding combination of events stored in the table; and perform the selected action. 
     Another aspect of the present disclosure provides a method for controlling a meter. The meter and a meter socket composing a metering system. The method comprising: detecting a plurality of different conditions of the meter; determining a plurality of events that have occurred based on the detected plurality of different conditions; comparing the plurality of events to a table stored in a memory of the meter, the table defining an action to be performed by the meter for each of different combinations of the plurality of events; selecting an action from the table for which the plurality of events match a corresponding combination of events stored in the table; and performing the selected action. 
     Another aspect of the present disclosure provides a meter comprising a memory, a plurality of sensors, and a processor. Each of the plurality of sensors is configured to detect a different condition of the meter. The processor is configured to: determine a plurality of events that have occurred based on the conditions detected by the sensors; compare the plurality of events to a table stored in the memory of the meter, the table defining an action to be performed by the meter for each of a plurality of different combinations of the plurality of events; select an action from the table for which the plurality of events match a corresponding combination of events stored in the table; and perform the selected action. 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Description of the Invention section. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. Furthermore, the claimed subject matter is not constrained to limitations that solve any or all disadvantages noted in any part of this disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       A more detailed understanding may be had from the following description, given by way of example in conjunction with the accompanying drawings, wherein: 
         FIG. 1  illustrates a metering system in which the systems, methods, and apparatus disclosed herein may be embodied. 
         FIG. 2  illustrates a schematic of the metering system of  FIG. 1 , according to an aspect of the disclosure. 
         FIG. 3  illustrates a schematic of a controller, according to an aspect of the disclosure. 
         FIG. 4  illustrates a flow diagram for monitoring metering operations within a metering system, according to an aspect of the disclosure. 
         FIG. 5  illustrates a table of example scenarios for meter responses, according to an aspect of this disclosure. 
     
    
    
     DESCRIPTION OF THE INVENTION 
     The disclosure relates generally to metering systems and methods for monitoring consumption of a commodity, such as electricity. Although the system and methods are described herein in the context of a system for metering electrical energy consumption, it is understood that the system and methods described herein may be implemented in systems that monitor consumption of other commodities, such as, for example, water or gas. In one embodiment, the metering system includes a meter and a meter socket located at a customer location. The metering system includes a means for obtaining information from the meter and meter socket. This could be a physical connection such as a cable between the meter and device in the socket, a wireless RF connection, or other means. In this description, the meter includes at least one sensor, and the meter socket includes an information storage device comprising identification information. As used herein, the term “information storage device” will be understood to include a means to store identification information in the meter socket and a means to communicate that information to the meter as described in further detail below. When the meter is coupled to the meter socket, at least one sensor may obtain information from the metering system, such as the identification information from the information storage device, a movement of the meter, a magnetic field, a power interruption, a reverse energy, an excessive number of security access failures, a current transformer saturation, or still other meter information. Based on the information obtained from the at least one sensor, the metering system may determine an appropriate response or action. 
       FIG. 1  provides a perspective view of a metering system  90  having a meter  100  and a meter socket  112  that may be installed at a utility customer location. The meter socket  112  may, in turn, be connected to one or more electrical loads at the customer location. In one embodiment, the meter socket  112  is configured to receive and electrically connect with blades  101  of the meter  100 . Meter  100  may include a meter cover  103  and may be any type of meter configured to measure and indicate the amount of energy consumption at a customer location, such as a residence, industry or business. 
     Meter  100  may be part of a metering network in which the methods, systems, and apparatus disclosed herein may be employed. The metering network may comprise a plurality of meters  100 , which are operable to sense and record consumption or usage of a service or commodity. Meters  100  may be located at customer premises, such as a home or place of business. Meters  100  comprise circuitry for measuring the consumption of the service or commodity being consumed at their respective locations and for generating data reflecting the consumption, as well as other data related thereto. Meters  100  may also comprise circuitry for wirelessly transmitting data generated by the meter to a remote location. Meters  100  may further comprise circuitry for receiving data, commands or instructions wirelessly as well. Meters that are operable to both receive and transmit data may be referred to as “two-way” meters, while meters that are only capable of transmitting data may be referred to as “transmit-only” or “one-way” meters. In bi-directional meters, the circuitry for transmitting and receiving may comprise a transceiver. 
     The meter socket  112  may further comprise an information storage device or tag  116 . The tag  116  may be attached to any part of the meter socket  112  with adhesive glue, double-sided or single-sided tape, soldering, or other similar adhesive commonly used by those skilled in the art. 
     The tag  116  may be a radio frequency identification (RFID) tag, such as a near field communication (NFC) tag. The tag  116  may contain electronically stored identification information that is unique to tag  116  and may be identified by using radio waves at, for example, a 13.56 MHz frequency. The tag  116  may contain an induction coil (not shown), that through excitation generated by a variable electromagnetic field generated by a reader, powers a small circuit (not shown) that is read by the reader through RF waves. In one embodiment, the tag  116  comprises an NFC tag, which is a subset of RFID tags. In one embodiment, the tag  116  is a passive device. In other embodiments, the tag  116  may be an active device. 
     In an aspect, every meter socket  112  within a metering network may be equipped with a tag  116  that includes identification information that uniquely identifies that meter socket. The identification information may include, for example, a geographic location of the meter socket  112 . Each tag  116  may be supplied in bulk, supplied with every meter  100 , or pre-installed in the meter socket  112 . For example, the tag  116  may be taped onto a cover of the meter  100  using a peel-off sticker. When a meter technician installs the meter  100  with the socket  112 , the tag  116  may be peeled off and coupled to the socket  112 . Each tag  116  may be pre-encoded or may be encoded by a technician installing the tag  116 . 
       FIG. 2  illustrates an embodiment of a meter  100 , according to an aspect of this disclosure. The meter  100  is interposed into electricity distribution lines  120 , and the meter  100  is disposed between an electrical energy source  102  and an electrical load(s)  114  at a utility customer location. In the embodiment shown, the meter  100  meters electrical energy delivered from the source  102  to the load  114  via distribution lines  120 . In particular, the meter  100  connects to a source-side of the distribution lines at contacts  120 A and  120 B and to a load-side at contacts  120 C and  120 D. The meter  100  measures the consumption of electrical energy by the load  114 . 
     As further shown, the meter  100  comprises a disconnect switch  104 , a controller  140 , and an optional communications interface  150 . The meter  100  may further comprise other components commonly used in metering devices. This description is specific to a single phase meter, but the principles are also applicable to polyphase electricity meters as well. 
     The disconnect switch  104  is interposed into the distribution lines  120  and is configured to switch between an open position, in which electrical energy is not supplied to the electrical load  114 , and a closed position, in which electrical energy is supplied to the electrical load  114 . Electrical energy (at meter inputs “L1 IN” and “L2 IN”) is supplied by the source  102  and delivered, via source side distribution lines  120 A and  120 B, through meter  100 , to the electrical load at the customer location  114  (via meter outputs “L1 OUT” and “L2 OUT”). Disconnect switch or electrical relay  104  is interposed into the distribution lines  120 , effectively separating the distribution lines into source side distribution lines  120 A and  120 B, and load-side distribution lines  120 C and  120 D. As shown, in this embodiment, the disconnect switch or relay  104  comprises two switches  106 ,  108 —one for each distribution line. When disconnect switch  104  is closed, electrical energy should be supplied to customer location  114 , and when disconnect switch  104  is open, no electrical energy should be supplied to customer location  114 . The switches  106 ,  108  may be driven by a motor, a solenoid, or other means commonly used to drive a disconnect switch. 
     The optional communications interface  150  may be configured to communicate with the controller  140  and a remote utility monitoring location  170 . The optional communications interface  150  may be a two-way communications interface to the remote utility monitoring location  170  (e.g. head-end system) and may comprise any suitable communications interface technology, such as a radio frequency (RF) transceiver, or an interface to the telephone lines or power lines at the customer location  114 , etc. The optional communication interface  150  may communicate with remote utility monitoring location  170  via communications link  175 . Communications link  175  may be a private or public network, such as a subnet/LAN. 
     The controller  140  may be configured to record data reflecting energy consumption measured by the meter  100  and to control various internal functions of the meter  100 . The controller  140  may be an electronic control unit, computing device, central processing unit, or other data manipulation device that may be used to facilitate control and coordination of any of the methods or procedures described herein. 
     In one embodiment, the controller  140  comprises a processor  142 , such as a microprocessor, microcontroller, or the like, a memory  144 , and sensors  146 . The processor  142  may be operatively coupled to the sensors  146 , the disconnect switch  104 , the memory  144 , and the optional communications interface  150 . The processor  142  may be configured to receive signals from the sensors  146 , the disconnect switch  104 , the memory  144 , and the optional communications interface  150 , to process the signals, and to store the signals in memory  144 . 
     The utility monitoring station  170  may send and receive commands to and from the meter  100  via communications link  175 . In response to a command, the controller  140  may operate the meter  100  by, for example, operating the disconnect switch  104  to open or close position, reading measured current or voltage information within the distribution lines  120 , or performing other metering operations. Information received by the controller  140  from the utility monitoring station  170 , sensors  146 , or other metering components may be stored in memory  144 . Information received by the controller  140  may also be provided to the remote utility monitoring location  170  to be stored remotely. 
       FIG. 3  illustrates a block diagram of an embodiment of the components that may comprise the controller  140 . Sensors  146  may include a current sensor  302 , a voltage sensor,  304 , an identification sensor  306 , a motion sensor  308 , a cover removal sensor  310 , a magnetic sensor  312 , or still other sensors. While the controller  140  is represented as a single unit, in other aspects the controller  140  may be distributed as a plurality of distinct but interoperating units, incorporated into another component, or located at different locations on or off the meter  100 . 
     The current sensor  302  and the voltage sensor  304  are configured to measure current flow and voltage, respectively, at contacts  120 A and  120 B on the source-side of the distribution lines  120 . In alternative aspects, the current sensor  302  and the voltage sensor  304  may be further configured to measure current and voltage, respectively, at contacts  120 C and  120 D on the load-side of the distribution lines  120 . The current sensor  302  and the voltage sensor  304  may provide signals to the processor  142  indicative of the current flow and voltage, respectively. 
     The identification sensor  306 , also referred to as a reader, may be coupled to the processor  142 . The identification sensor  306  is configured to obtain (e.g., read) the identification information from the tag  116  and provide a signal indicative of the identification information to the processor  142 . The sensor  306  may be an RFID reader and/or a NFC reader. 
     The motion sensor  308  may be coupled to the processor  142  and configured to sense a motion of the meter  100 . For example, the motion sensor  308  may be configured to sense a tilt or vibration of the meter  100  relative to the meter socket  112  due to, for instance, removal of the meter  100  from the socket  112  or an external force applied to the meter  100 . The motion sensor  308  may provide a signal indicative of the motion to the processor  142 . 
     The cover removal sensor  310  and the magnetic field sensor  312  may be coupled to the processor  142  and configured to sense whether the meter cover  103  has been removed from the meter  100  and whether a magnetic field exists at the meter  100  location, respectively. 
     Sensors  146  may further include devices capable of sensing reverse energy, detecting excessive security access failures, power interruption, detecting current transformer saturation, or still other metering parameters. 
     In accordance with an aspect of the system and method described herein, during installation of meter  100  into the meter socket  112  at a given customer location, the meter  100  may be paired with identification information of the tag  116  of the meter socket  112 . In one embodiment, a technician may use an installation tool (not shown) equipped with a tag reader to read the tag  116  of the meter socket and then  112  to input the identification information to the meter  100 . In other embodiments, the sensor  302  of the meter  100  may automatically read the identification information from the tag  116  upon insertion of the meter  100  into the socket  112  during initial installation. The meter  100  may then store information indicative of its pairing with the identification information for the socket  112 . In this respect, the stored identification information obtained from the tag  116  of the meter becomes the “expected” identification information for that meter. This pairing of the meter  100  with the identification information of the tag  116  may also be recorded by the technician using the installation tool, or the pairing may be reported by the meter  100  to the remote utility monitoring location  170  via the communication interface  150 . 
     Thereafter, in operation, upon power up of the meter  100 , the sensor  302  may read the tag  116  attached to the meter socket  112  to obtain its identification information and may compare the identification information read from the tag  116  to the “expected” identification information recorded during the initial meter pairing. 
       FIG. 4  illustrates a method  400  for determining a meter response based on conditions of the meter  100  (e.g. a tamper event), according to an aspect of this disclosure. The method  400  may begin by power cycling the meter  100  (e.g., power up after a power down). At step  402 , the meter  100  determines whether the motion sensor  308  is enabled. If the motion sensor  308  is enabled, then at step  404 , a condition of the meter  100  is sensed, for example, a motion of the meter  100 , by the motion sensor  308 . The condition of the meter  100  may be stored in memory  144 . At step  406 , the processor  142  determines whether a motion of the meter  100  has been detected. Determining whether motion has been detected may include a motion test. The motion test may include, for example, sensing a frequency of the motion (e.g. 4 movements/tilts) of the meter  100  over a certain time period (e.g. 2 minutes). If 4 movements/tilts of the meter  100  are sensed within the 2 minute time period, the meter  100  fails the motion test, indicating that motion of the meter  100  has been detected. At step  408 , if motion has been detected, the processor  142  may log this in memory  144  as a ‘fail’ event and may send an alert to the remote utility monitoring location  170 . Conversely, if motion of the meter  100  has not been detected, the processor  142  may log this in memory  122  as a ‘pass’ event. 
     If the motion sensor  308  has not been enabled, or after motion detection has occurred, then at step  410 , the meter  100  determines whether the identification sensor  306  is enabled. If the identification sensor  306  is enabled, then at step  412 , the identification information is read from tag  116  by the identification sensor  306 . The identification sensor  306  provides a signal to the processor  142  indicative of the identification information. The processor  142  may store the identification information from the tag  116  in memory  144 . At step  414 , the processor  142  compares the signal indicative of the identification information read from the tag  116  with the expected tag  116  identification information stored during the initial pairing of the meter  100  with the socket  112 . At step  416 , if the signal indicative of the identification information read from the tag  116  of the meter socket  112  does not match the expected identification information recorded during the pairing process, or the identification sensor  306  fails to read the tag  116  of the meter socket  112 , then the processor  142  may log this condition as a ‘fail’ event in memory  144  and may send an alert to the remote utility monitoring location  170 . Conversely, if the identification information read from the tag  116  does match the expected identification information recorded during the pairing process, the processor  142  may log this condition as a ‘pass’ event in memory  144 . 
     If the identification sensor  306  has not been enabled, or after identification detection has occurred, then at step  418 , the meter  100  determines whether the voltage sensor  304  is enabled. If the voltage sensor  304  is enabled, then at step  420 , a condition (e.g. a source-side voltage or a load-side voltage) at the meter  100  is detected by the voltage sensor  304  and stored in memory  144 . At step  422 , the processor  142  determines whether a voltage of the meter  100  has been detected. Determining whether voltage has been detected may include a power fail test. The power fail test may include, for example, sensing a source-side voltage of the meter  100  over a certain time period (e.g. 2 minutes). If there is no source-side voltage sensed for more than the 2 minute time period, the meter  100  fails the power fail test, indicating that voltage has not been detected at the meter  100 . At step  424 , if voltage has not been detected, the processor  142  may log this event in memory  144  and may send an alert to the remote utility monitoring location  170 . 
     If the voltage sensor  304  has not been enabled, or after voltage detection has occurred, then at step  426 , the meter  100  determines whether the cover removal sensor  310  is enabled. If the cover removal sensor  310  is enabled, then at step  428 , the cover removal sensor  310  senses a condition (e.g. whether the meter cover  103  has been removed from the meter  100 ) and stores an indication of whether the cover  113  has been removed from the meter  100  in memory  144 . If the processor  142  determines the cover  113  has been removed ( 430 ) from the meter, at step  432 , the processor  142  may log this event in memory  144  and may send an alert to the remote utility monitoring location  170 . 
     The method  400  only illustrates one example of detecting an abnormal condition. Fewer sensors  146  may be used, or more sensors  146  may be used, for example, the magnetic field sensor  312 . Additionally, the order in which the sensors are checked to determine whether they are enabled may vary. For example, the status of the cover removal sensor  310  may be checked prior to the status of the motion sensor  308 . 
     If the magnetic field sensor  312  is enabled, the magnetic field sensor  312  may sense a condition (e.g. a magnetic field) at the meter  100 . The processor  142  may determine whether a magnetic field has been detected using a magnetic field test. The magnetic field test may include, for example, a magnetic field sensor threshold (e.g. 1.2 Volts) and a time duration that the magnetic field sensor&#39;s output is above the threshold (e.g. 10 seconds). If the sensed magnetic field sensor&#39;s output is above 1.2 Volts for more than 10 seconds, the meter  100  fails the magnetic field test. An indication of this failure event may also be used in determining whether an appropriate response of the meter  100 . 
     Each of the sensors  146  may be configured to provide a set of inputs to the processor  142 . For example, the following indicators for the conditions detected by the sensors  146  may be provided to the processor  142  during the method  400 : an indication of whether the sensor  146  is enabled, whether a threshold has been exceeded, a frequency with which the threshold has been exceeded, and the time duration the threshold has been exceeded. Each of the indicators provided to the processor  142  may be used to determine whether each test (e.g. motion test, power fail test, identification test, cover removal test, and magnetic field test) has failed or passed. The result of each test or the status of the particular sensor  146  (e.g. pass, fail, or not enabled) may be stored in memory  144  as an event. 
     Based on each of the indicators for the conditions sensed by the sensors  146  logged in memory  144 , at step  434 , the meter  100  may determine an appropriate response. For example, the meter may respond by recording billing information to an alternate register, taking a billing snapshot, logging the abnormal condition in memory  144 , disabling the optional communications module  150 , controlling the disconnect switch  104  to the open position, sending alarms to the remote utility monitoring location  170 , or still other responses. 
       FIG. 5  illustrates a table  500  stored in the memory  144  of the meter  100  in accordance with one embodiment. As shown, the table comprises a plurality of entries  502 ,  503 ,  504 ,  505 , and  506 , each of which defines an action to be performed. For example, for a particular combination of detected events, the detected events are compared to the events stored in table  500 , and an action is selected for the meter  100  to perform based on how the detected events align with the stored events. Table  500  is merely exemplary and only shows an example of five different combinations of events stored in memory  144  and their corresponding meter  100  responses. 
     Each sensor  146  may either be enabled or not enabled. If the sensor  146  is enabled, then the processor  142  may determine whether the test corresponding to the particular sensor  146  has passed or failed. For example, the first entry  502  of the table  500  illustrates a first plurality of events that indicate that the motion detect test, tag detection, voltage detection, and cover removal tests have all been enabled and have all passed. The magnetic field test has not been enabled, and therefore, has neither passed nor failed. Based on the results of each enabled test, the first entry  502  indicates that the meter  100  has no response and continues to monitor consumption. The second entry  503  of the table  500  illustrates a second plurality of events that indicates that the motion detect test and the voltage detection have been enabled and have both failed. The tag detection, cover removal, and magnetic field detection tests have not been enabled, and therefore, have neither passed nor failed. Based on the results of each enabled test, the second entry  503  indicates that the meter  100  response is to send an alarm to the remote utility monitoring location  170 . The remaining entries  504  through  506  in table  500  each illustrate additional examples of various events of test results and corresponding meter responses. 
     It will be appreciated that the list of scenarios  502  through  506  is merely demonstrative, and more scenarios and corresponding responses may be contemplated and stored in memory  144 . Further, additional or fewer tests may be incorporated into each scenario in order to determine the appropriate meter  100  response. 
     It will be appreciated that the method  400  may be repeated at a desired frequency. For example, the method  400  may repeat after every power cycle of the meter  100 , or the method  400  may repeat on an hourly, daily, or weekly basis. 
     While the disclosure is described herein using a limited number of embodiments, these specific embodiments are for illustrative purposes and are not intended to limit the scope of the disclosure as otherwise described and claimed herein. Modification and variations from the described embodiments exist. The scope of the invention is defined by the appended claims.