Patent Description:
<CIT> discloses an electricity larceny prevention circuit for an intelligent electric energy meter based on an MEMS acceleration sensor, and the circuit is characterized in that a single-chipmicrocomputer is electrically connected with a MEMS acceleration sensor circuit, a storage module circuit, and a temperature measurement circuit. The circuit can achieve the monitoring of suspected behaviors no matter whether the intelligent electric energy meter carries out the supply of power or not, and changes the passive electricity larceny prevention into the active electricity larceny prevention.

<CIT> discloses apparatus and methodologies for detecting inversion tamper, removal tamper, and taps using a three-axes accelerometer sensor in a utility meter environment. Inversion tamper is detected upon power up if the acceleration value along Y axis is greater than or equal to some small positive threshold. Removal tamper is detected if the average acceleration change of both Y and Z axes is greater than or equal to the removal threshold. A tap is detected if the average acceleration change along the X axis is greater than or equal to the tap threshold. The initial acceleration values are set upon power up. Removal tamper detection and tap detection are distinguished using a moving average filter. Tap detection uses timing constraints to avoid false tap detections.

In <CIT> devices to detect utility theft are provided, as well as methods of their use. The devices are utility meters that have a positioning detector; a microprocessor connected to receive readings from the positioning detector; a memory storage device in communication with the microprocessor, and at least one power source to provide power to the microprocessor and the memory storage device. Combining positioning readings with theft detection algorithms allows increased accuracy in the automated detection of theft, even when grid power is not available to power the accelerometer or compass.

<CIT> relates to a device for detecting whether power measurement device is attacked or not comprising a main control unit and a detection unit. The main control unit includes a main control module and the detection unit includes a detection control module, a 35kV high-voltage discharge detection module, and vibration and physical displacement. The main control module, the 35kV high voltage discharge detection module, the vibration and physical displacement detection module, and a strong magnetic detection module are respectively electrically connected with the detection control module.

<CIT> describes an electricity larceny prevention method based on a multi-dimensional positioning technology of an electric energy meter. The method comprises adding a positioning chip to an electric energy meter control circuit, wherein the positioning chip automatically communicates with the Beidou or GPS in real time to obtain positioning information of the electric energy meter; an electric energy meter master control CPU reads the positioning information from the positioning chip through a serial communication data interface, and compares the positioning information with the positioning information acquired for the first time when the electric energy meter is installed to generate event information about the position change of the electric energy meter; a court acquiring terminal sends the event information to a main station, and the main station confirms an electricity larceny position and related information through multi-dimensional analysis. The method can also generate an accurate topological map of the location of all the electric energy meters in a province and a distribution network, monitors the changes of the position information of the electric energy meters in real time, ensures the real-time performance of the customer service panorama, can determine the position information of the fault point accurately and quickly when a fault occurs to a certain electric energy meter in the distribution network, and provides real-time information support for rapid repair.

<CIT> relates to a meter reading device and system. A remote unit includes an electronics assembly, a housing, and a fastening member. The electronics assembly includes a communications module and an image sensor, having a lens with a field of view, that captures images of a display of a meter. The housing includes a cover coupled to a base member. The base member couples to the meter and includes an aperture. The electronics assembly is retained between the base member and the cover, such that the lens aligns with the aperture. The fastening member receives a portion of the housing in a hollow section. A mechanism of the fastening member attaches to a portion of the meter, maintaining the display in the field of view. The communications module transmits image data, derived from the captured images, to a hub unit. The hub unit processes the image data, and forwards information extracted from the image data to a remote server.

One issue that utilities face is unreported damage to their assets, of which one such asset is the electric meter. A further challenge for utilities is that many meter installations (meter bases and load side wiring) are the property of the energy consumer (e.g., home owner or landlord). Damage to meter installations can occur suddenly in the case of storm or vehicle damage or slowly in the case of earth settling or heaving over many years and may not be noticed or reported by the energy consumer. Improper orientation can be an indication of damage to the electric meter or the electric meter installation.

Systems and methods for detecting changes in the orientation of an electric meter are provided.

According to various aspects of the present disclosure there is provided a method, as defined in claim <NUM>. Further, when the difference exceeds the threshold value, a timestamped event may be recorded and an alarm flag may be set.

In some cases, determining the initial orientation of the electric meter may include executing a firmware procedure to initiate the initial accelerometer measurements on the electric meter during installation. In some cases, determining the initial orientation of the electric meter may include initiating the initial accelerometer measurements from the accelerometer by the electric meter when the electric meter first registers on a network and transitions to an operational mode at an installation site.

Continuously monitoring the subsequent acceleration measurements from the accelerometer may include receiving acceleration measurements from the accelerometer at predetermined time intervals.

In some cases, determining a difference between the initial orientation and the subsequent orientation comprises determining a difference between the initial acceleration measurements and the subsequent acceleration measurements. In some cases, determining a difference between the initial orientation and the subsequent orientation may include determining an initial tilt angle of the electric meter based on the initial acceleration measurements, determining a subsequent tilt angle of the electric meter based on the subsequent acceleration measurements, and comparing the initial tilt angle to the subsequent tilt angle.

The method may further include determining a tilt angle difference of the electric meter at the predetermined time intervals when the acceleration measurements from the accelerometer are received. The tilt angle of the electric meter may be an angle in a front-to-back direction with respect to a front face of the electric meter, an angle in a side-to-side direction with respect to a front face of the electric meter, or an angle in a rotation direction around a vertical axis of the electric meter.

According to various aspects of the present disclosure there is provided an electric meter, as defined in claim <NUM>. Further, when the difference exceeds the threshold value, a timestamped event may be recorded and an alarm flag may be set.

In some cases, the processor of the electric meter may be further configured to determine a difference between the initial orientation and the subsequent orientation by determining a difference between the initial acceleration measurements and the subsequent acceleration measurements. In some cases, the processor of the electric meter may be further configured to determine a difference between the initial orientation and the subsequent orientation by: determining an initial tilt angle of the electric meter based on the initial acceleration measurements, determining a subsequent tilt angle of the electric meter based on the subsequent acceleration measurements, and comparing the initial tilt angle to the subsequent tilt angle.

The processor may be further configured to receive the subsequent acceleration measurements at predetermined time intervals, and may be further configured to determine a tilt angle difference at the predetermined time intervals when the acceleration measurements from the accelerometer are received. The tilt angle of the electric meter may be an angle in a front-to-back direction with respect to a front face of the electric meter, an angle in a side-to-side direction with respect to a front face of the electric meter, or an angle in a rotation direction around a vertical axisof the electric meter.

According to various aspects of the present disclosure there is provided a system, as defined in claim <NUM>.

Further, when the difference exceeds the threshold value, a timestamped event may be recorded and an alarm flag may be set.

In some cases, the processor may be further configured to determine a difference between the initial orientation and the subsequent orientation by determining a difference between the initial acceleration measurements and the subsequent acceleration measurements. In some cases, the processor may be further configured to determine a difference between the initial orientation and the subsequent orientation by: determining an initial tilt angle of the electric meter based on the initial acceleration measurements, determining a subsequent tilt angle of the electric meter based on the subsequent acceleration measurements, and comparing the initial tilt angle to the subsequent tilt angle.

The processor may be further configured to receive the subsequent acceleration measurements at predetermined time intervals, and may be further configured to determine a tilt angle difference at the predetermined time intervals when the acceleration measurements from the accelerometer are received.

Aspects and features of the various embodiments will be more apparent by describing examples with reference to the accompanying drawings, in which:.

While certain embodiments are described, these embodiments are presented by way of example only, and are not intended to limit the scope of protection. The apparatuses, methods, and systems described herein may be embodied in a variety of other forms. Furthermore, various omissions, substitutions, and changes in the form of the example methods and systems described herein may be made without departing from the scope of protection.

Embodiments according to the present disclosure can detect possible changes to orientations of electric meter installations. Changes such as tilting of an electric meter from an initial orientation when the electric meter was installed can create safety or power quality issues. For example, changes to the orientation of the electric meter installation could create strain on electrical conductors or connectors, or even expose the electrical conductors resulting in shock or fire hazards. Detection of changes in the orientation of the electric meter installation can prevent loss of life as well as damage to structures and electrical equipment.

<FIG> is a block diagram illustrating electrical connections to an electric meter and meter socket. The meter and meter socket are located at the customer premises. The meter measures and controls the electricity delivered to the customer premises via the electric distribution system (i.e., the grid). The meter may be combined with a communications module to enable the meter to communicate with other meters and with the utility. As illustrated in <FIG>, power from the grid <NUM> (i.e., the electric distribution system) is supplied to the meter socket <NUM> via electrical wiring L1 and L2. Electrical wiring L1 and L2 may provide power from two phases of the grid. The neutral wire N, sometimes referred to as ground, is connected between the grid <NUM> and the electrical service <NUM>, for example, at an electrical service panel at a residential or commercial customer premises. In some installations, the neutral wire N may not have a connection within the meter socket. In other installations, the neutral wire N may be connected within the meter socket.

The electrical service <NUM> is also connected to the meter socket <NUM> via corresponding electrical wiring L1 and L2. The meter socket <NUM> includes electrical connectors to provide electrical connections to the meter <NUM> when the meter <NUM> is plugged into the meter socket <NUM>. An electrical connection between the grid <NUM> and the electrical service <NUM> is formed through the meter <NUM> when the meter <NUM> is plugged into the meter socket <NUM>. Within the meter <NUM>, voltage and current provided by the grid <NUM> to the electrical service <NUM> is measured, or metered, by measuring devices <NUM>, for example, voltage transformers and current transformers. Power delivered to the electrical service <NUM> may be calculated based on the voltage and current measurements.

<FIG> is a block diagram illustrating an example implementation of an electric meter according to aspects of the present disclosure. Referring to <FIG>, the electric meter <NUM> may include a processor <NUM>, a memory <NUM>, an accelerometer <NUM>, and a communications module <NUM>.

The processor <NUM> may be a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device. The processor <NUM> may be in electrical communication with the accelerometer <NUM>, the memory <NUM>, and the communications module <NUM>, and may control overall operation of the electric meter <NUM>. The processor <NUM> may receive data generated by various sensors of the electric meter <NUM> including, but not limited to, data generated by the accelerometer <NUM> and may perform operations on, or processing of, the data. In some implementations, the data generated by the accelerometer <NUM> may be timestamped by the accelerometer <NUM> or the processor <NUM>. In some implementations, the accelerometer data may not include a timestamp.

The memory <NUM> may be a storage device such as a solid state storage device or other storage device, and may be a combination of volatile and non-volatile storage or memory. In some implementations, portions of the memory may be included in the processor <NUM>. The memory <NUM> may be configured to store instructions executable by the processor <NUM> as well as data generated by various sensors of the electric meter <NUM> including, but not limited to, data generated by the accelerometer <NUM>.

In accordance with aspects of the present disclosure, when the electric meter <NUM> is installed in a meter socket, the accelerometer <NUM> may monitor vibrations experienced by the electric meter <NUM>. The processor <NUM> may receive timestamped data from the accelerometer <NUM> or may receive and timestamp the accelerometer data. In some implementations, the processor <NUM> may cause the timestamped accelerometer data to be stored, for example in the memory <NUM> or other storage. The accelerometer data may be stored for a specified period of time.

The communications module <NUM> may be a wired or wireless transceiver operable to communicate via various wired or wireless protocols as known in the field. The communications module <NUM> may enable the electric meter <NUM> to communicate with other meters and with the utility provider, for example, with a head-end system. The communications module may be, for example, a radio frequency (RF) transceiver configured to wirelessly communicate with a head-end system and other electric meters and devices in a communications network. Many technologies are available for RF communications, for example, but not limited to, Cat-M, Cat-<NUM>, NB-IoT, ZigBee, Bluetooth, Wi-Fi, Wi-SUN, and cellular, as well as proprietary protocols, and the technologies may use many different frequencies.

The head-end system may be, for example, a server situated in an office location of a utility provider. The head-end system may communicate with the electric meters to collect meter identification information such as serial numbers, advanced metering infrastructure (AMI) identifiers, other utility-specific identifiers, as well as data generated by the electric meters such as global positioning system (GPS) coordinates, voltage and current data, accelerometer data, and notifications. The communications module <NUM> may transmit data and alarm signals to the utility provider head-end system and receive any of updated program instructions, firmware updates, updates to other settings, or other communications.

The accelerometer <NUM> may be a <NUM>-axis accelerometer, a <NUM>-axis accelerometer, or other accelerometer. The accelerometer <NUM> may be operable to detect static acceleration due to gravity. By measuring the amount of static acceleration due to gravity, the accelerometer <NUM> or the processor <NUM> can determine the angle the electric meter <NUM> is tilted at with respect to the earth. In some implementations, the accelerometer <NUM> may be operable to detect vibrations in a range of several hertz to several hundred hertz. Thus, the accelerometer <NUM> may detect vibrations due to insertions and removals of the electric meter.

When an electric meter is installed at a customer premises, for example, on a vertical mounting surface such as pole or on a side of a building, the electric meter is oriented such that a front face of the electric meter is substantially parallel to the vertical mounting surface (e.g., the meter is plumb). The electric meter is thus considered to be mounted in a vertical orientation. Measurements from an accelerometer, for example, the accelerometer <NUM>, positioned in the electric meter can be used to determine the orientation of the electric meter with respect to gravity when the electric is installed.

In some example embodiments, initial orientation measurements may be obtained from the accelerometer by causing the electric meter to execute a firmware procedure. The firmware procedure may be initiated by a technician and may cause the accelerometer to perform the static acceleration measurements, and the initial orientation determination may be performed by the accelerometer and/or the processor of the electric meter based on the accelerometer signals. In some embodiments, the initial orientation measurements may be initiated by the electric meter when the electric meter registers with the utility provider network and transitions to an operational mode at the installation site.

The accelerometer measurements obtained when the electric meter is installed may be stored, for example, in the memory <NUM> of the electric meter, as the baseline orientation. Alternatively or initially, the processor of the electric meter may cause the baseline orientation to be communicated to the head-end system via the communications module. The baseline accelerometer measurements may be compared with subsequently obtained accelerometer measurements to determine whether the orientation of the electric meter has changed. In some cases, the baseline accelerometer measurements may be compared directly with subsequently obtained accelerometer measurements. In other cases, tilt angles of the electric meter determined based on the baseline accelerometer measurements and tilt angles of the electric meter determined based on the subsequently obtained accelerometer measurements may be compared.

<FIG> is a diagram illustrating a change in electric meter orientation in a front-to-back direction. Referring to <FIG>, in an initial installation <NUM>, an electric meter <NUM> may be installed in a substantially vertical orientation. Measurements may be obtained from the accelerometer positioned in the electric meter to establish a baseline orientation of the electric meter in the front-to-back (e.g., pitch) direction with respect to a front face of the electric meter. In some examples, the processor of the electric meter may receive the accelerometer measurements and determine the baseline orientation of the electric meter in the front-to-back direction. In some examples, the accelerometer may determine the baseline orientation of the electric meter in the front-to-back direction from the obtained measurements and communicate the baseline orientation to the processor.

The electric meter orientation in the front-to-back direction may be determined as a tilt angle α (e.g., a difference angle from a true vertical direction) of the electric meter. The baseline front-to-back orientation measurements may be stored, for example, in the memory of the electric meter. Alternatively or additionally, the processor may cause the communications module to communicate the baseline front-to-back orientation measurements to the head end system.

In some example embodiments, the accelerometer may continuously measure the front-to-back orientation of the electric meter and communicate the measurements or the determined front-to-back orientation to the processor. In some example embodiments, the accelerometer may measure the front-to-back orientation of the electric meter at predetermined time intervals, for example, periods of seconds, minutes, hours, days, etc., and communicate measurements or the front-to-back orientation of the electric meter to the processor.

Various external conditions, for example, high wind, structural deterioration, vehicle impact, land settling, etc., can cause the orientation of the electric meter to tilt in a forward direction <NUM> or backward direction <NUM> with respect to a frame of reference of the electric meter <NUM>. In some cases, the change in orientation may be sudden, for example, as a result of a vehicle impact with a pole or wall on which the electric meter <NUM> is mounted. In some cases, the change in orientation may occur over a period of time, for example, as the land around the electric meter <NUM> settles. The accelerometer positioned in the electric meter <NUM> can detect the changes in orientation by determining a change in magnitude of a gravity vector measured along the appropriate axes.

<FIG> is a diagram illustrating a change in electric meter orientation in a side-to-side direction. Referring to <FIG>, in an initial installation <NUM>, an electric meter <NUM> may be installed in a substantially vertical orientation. Measurements may be obtained from the accelerometer positioned in the electric meter to establish a baseline orientation of the electric meter in the side-to-side (e.g., roll) direction with respect to a front face of the electric meter. In some examples, the processor of the electric meter may receive the accelerometer measurements and determine the baseline orientation of the electric meter in the side-to-side direction. In some examples, the accelerometer may determine the baseline orientation of the electric meter in the side-to-side direction from the obtained measurements and communicate the baseline orientation to the processor.

The electric meter orientation in the side-to-side direction may be determined as a tilt angle β (e.g., a difference angle from a true vertical direction) of the electric meter. The baseline side-to-side orientation measurements may be stored, for example, in the memory of the electric meter. Alternatively or additionally, the processor may cause the communications module to communicate the baseline side-to-side orientation measurements to the head end system.

In some example embodiments, the accelerometer may continuously measure the side-to-side orientation of the electric meter and communicate the measurements or the determined side-to-side orientation of the electric meter to the processor. In some example embodiments, the accelerometer may measure the side-to-side orientation of the electric meter at predetermined time intervals, for example, periods of seconds, minutes, hours, days, etc., and communicate measurements or the side-to-side orientation to the processor.

Various external conditions, for example, high wind, structural deterioration, vehicle impact, land settling, etc., can cause the orientation of the electric meter to tilt in a left side direction <NUM> or right side direction <NUM> with respect to a frame of reference of the electric meter <NUM>. In some cases, the change in orientation may be sudden, for example, as a result of a vehicle impact with a pole or wall on which the electric meter <NUM> is mounted. In some cases, the change in orientation may occur over a period of time, for example, as the land around the electric meter <NUM> settles. The measurements from the accelerometer positioned in the electric meter <NUM> can detect the changes in orientation by determining a change in magnitude of a gravity vector measured along the appropriate axes.

<FIG> is a diagram illustrating a change in electric meter orientation in a rotation direction around a vertical axis of the electric meter. Referring to <FIG>, in an initial installation <NUM>, an electric meter <NUM> may be installed in a substantially vertical orientation. Measurements may be obtained from the accelerometer positioned in the electric meter to establish a baseline orientation of the electric meter in the rotation (e.g., yaw) rotation direction around the vertical axis of the electric meter. In some examples, the processor of the electric meter may receive the accelerometer measurements and determine the baseline orientation of the electric meter in the rotation direction. In some examples, the accelerometer may determine the baseline orientation of the electric meter in the rotation direction from the obtained measurements and communicate the baseline orientation to the processor.

The electric meter orientation in the rotation direction may be determined as a tilt angle γ of the electric meter. The tilt angle γ may be taken as an angle of zero degrees rotation around the vertical axis of the electric meter. The baseline rotation orientation measurements may be stored, for example, in the memory of the electric meter. Alternatively or additionally, the processor may cause the communications module to communicate the baseline rotation orientation measurements to the head end system.

In some example embodiments, the accelerometer may continuously measure the rotation orientation of the electric meter and communicate the measurements or the determined rotation orientation of the electric meter to the processor. In some example embodiments, the accelerometer may measure the rotation orientation of the electric meter at predetermined time intervals, for example, periods of seconds, minutes, hours, days, etc., and communicate measurements or the rotation orientation to the processor.

Various external conditions, for example, high wind, structural deterioration, vehicle impact, land settling, etc., can cause the orientation of the electric meter to tilt in a left rotation direction <NUM> or right rotation direction <NUM> with respect to a vertical axis of the electric meter <NUM>. In some cases, the change in orientation may be sudden, for example, as a result of a vehicle impact with a pole or wall on which the electric meter <NUM> is mounted. In some cases, the change in orientation may occur over a period of time, for example, as the land around the electric meter <NUM> settles. The measurements from the accelerometer positioned in the electric meter <NUM> can detect the changes in orientation by determining a change in magnitude of a gravity vector measured along the appropriate axes.

According to aspects of the present disclosure, the change in orientation of the electric meter detected by the accelerometer measurements may be compared to a threshold. For example, the processor of the electric meter may receive the accelerometer signals and calculate a tilt angle α in a front-to-back direction, a tilt angle β in a side-to-side direction or a tilt angle γ in the rotation direction, or tilt angles in all of the front-to-back, side-to-side, and rotation directions compared to the baseline orientation of the electric meter. In some implementations, the threshold value may be specified as a positive value and the absolute values of the tilt angles may be taken for the comparison. In other implementations, the threshold value may be specified as signed values (e.g., ±<NUM> degrees) and the tilt angles compared according to their signed values. When the value of the front-to-back tilt angle α or the side-to side tilt angle β or the rotation tilt angle γ exceeds a threshold, for example <NUM> degrees or another angle from the baseline orientation of the electric meter, the processor may cause the communications module to generate a notification to the head-end system. The notification may include a timestamped event recorded in a location in the memory (e.g., the memory <NUM>) or in a register in the processor (e.g., the processor <NUM>) and an alarm flag may set in a location in the memory or in a register in the processor. When a notification is generated, a technician may be dispatched to investigate the cause of the notification.

In some cases, the accelerometer signals may indicate oscillations, for example, caused by a pole on which the electric meter is mounted swaying in high winds. The oscillations detected by the accelerometer may be an indication that the electrical wiring connected to the pole may be experiencing excessive strain that may ultimately result in downed wires or other failure conditions. In some embodiments, the electric meter may apply a filter (not shown) to detect and filter out temporary oscillations due to typical wind conditions.

While <FIG> illustrate an electric meter installed on a pole, other installations, for example on the wall of a building, may be used without departing from the scope of the present disclosure.

<FIG> is a block diagram illustrating communications between electric meters and a head end system according to some aspects of the present disclosure. Referring to <FIG>, electric meters <NUM>, <NUM>, <NUM> may be in communication with a head-end system <NUM> via communication links <NUM> and may be in communication with each other via communication links <NUM>. The head-end system <NUM> may include a server <NUM> configured to communicate with electric meters <NUM>, <NUM>, <NUM> over a network, for example in Advanced Metering Infrastructure (AMI) network. Each electric meter <NUM>, <NUM>, <NUM> may communicate meter information and data with other electric meters and with the server <NUM> in the head end system <NUM>. In some cases, an electric meter, for example electric meter <NUM>, may be too remote from the head-end system <NUM> to communicate with it directly. In such cases, the electric meter <NUM> may communicate with the head-end system <NUM> via another electric meter, for example electric meter <NUM>.

In some cases, communications between electric meters and the head-end system may be communicated through additional networks (not shown). Additionally or alternatively, the electric meters may communicate with one or more edge processing device located topologically closer to the electric meters than to the head-end system. The edge processing device may have more processing capability than the electric meters and may provide some of the functionality typically provided by the head-end system.

The electric meters <NUM>, <NUM>, <NUM> may communicate with each other via communication links <NUM> to exchange meter information and data. For example, if electric meter <NUM> experiences a loss of line voltage, electric meter <NUM> may communicate with electric meter <NUM> and electric meter <NUM> to determine if the failure is local to electric meter <NUM> or whether the failure is a more widespread fault caused by a common condition. A common condition may be, for example, downed power lines due to a storm. The common condition may then be reported to the head-end system by one or more of the electric meters. Additionally or alternatively, an edge processing device may receive data from the electric meters and determine whether the data indicates a common condition affecting the electric meters.

<FIG> is a flowchart illustrating a method <NUM> for measuring tilt of an electric meter according to some aspects of the present disclosure. Referring to <FIG>, at block <NUM>, an electric meter may be installed at a customer premises. For example, the electric meter may be installed on a pole or on the wall of a building or other structure. The electric meter may be installed in a substantially vertical orientation such that a front face of the electric meter is substantially parallel to the vertical mounting surface (e.g., the meter is plumb). The electric meter is thus considered to be mounted in a vertical orientation.

At block <NUM>, a baseline orientation of the electric meter may be established. An accelerometer positioned in the electric meter may be operable to detect static acceleration of the electric meter due to gravity. By measuring the amount of static acceleration due to gravity, the angle that the electric meter is tilted at with respect to the earth can be determined when the electric meter is installed at the customer premises. For example, the accelerometer measurements may be received by the processor of the electric meter, and the processor may perform calculations to determine a tilt angle. Alternatively, the accelerometer may perform the calculations to determine a tilt angle based on the measurements and communicate the tilt angle to the processor of the electric meter.

The accelerometer measurements or the tilt angle or both obtained at installation of the electric meter may be stored in the memory of the electric meter as the baseline orientation. Alternatively or initially, the processor of the electric meter may cause the baseline orientation to be communicated to the head-end system via the communications module. The baseline orientation may be established in the front-to-back (e.g., pitch) direction, the side-to-side (e.g., roll) direction, and the rotation (e.g., yaw) direction of the electric meter as illustrated in and explained with respect to <FIG>.

At block <NUM>, acceleration of the electric meter due to gravity may continue to be measured. After installation, the accelerometer positioned in the electric meter may continue to measure the acceleration due to gravity of the electric meter in both the front-to-back (e.g., pitch), side-to-side (e.g., roll), and rotation (e.g., yaw) directions. In some example embodiments, the accelerometer may continuously measure the acceleration due to gravity of the electric meter. In some example embodiments, the accelerometer may measure the acceleration due to gravity of the electric meter at predetermined time intervals, for example, periods of seconds, minutes, hours, days, etc. The accelerometer may communicate the measurements to the processor of the electric meter.

At block <NUM>, a subsequent orientation of the electric meter may be determined. The subsequent orientation of the electric meter may be determined based on the subsequent acceleration measurements. The accelerometer measurements may be received by the processor of the electric meter, and the processor may perform calculations to determine a tilt angle of the electric meter. Alternatively, the accelerometer may perform the calculations to determine a tilt angle based on the measurements and communicate the tilt angle to the processor of the electric meter. A tilt angle may be determined in both the front-to-back direction, side-to-side direction, and rotation direction of the electric meter.

At block <NUM>, a difference between the initial and subsequent orientations of the electric meter may be determined. In some example embodiments, the processor may compare the tilt angles based on the subsequent accelerometer measurements to the tilt angles of the baseline orientation (e.g., the front-to-back, side-to-side, and rotation tilt angles at the time of electric meter installation). In some example embodiments, the processor of the electric meter may compare the subsequent accelerometer measurements with the accelerometer measurements obtained at the time of electric meter installation without calculating tilt angles.

At block <NUM>, the tilt angles or acceleration measurements may be compared to threshold values. The processor of the electric meter may determine whether the absolute value of the difference in the front-to-back tilt angle (e.g., the angle α in <FIG>) or the difference in the side-to-side tilt angle (e.g., the angle β in <FIG>) or the rotation tilt angle e.g., the angle γ in <FIG>) or all of the tilt angles exceeds the threshold value. The threshold value may be a difference in angle of, for example, <NUM> degrees or another angle from the baseline orientation. The threshold value for the front-to-back orientation, the side-to-side orientation, and the rotation orientation directions of the electric meter may be the same as or different. In some implementations, the threshold value may be specified as a positive value and the absolute values of the tilt angles may be taken for the comparison. In other implementations, the threshold value may be specified as signed values (e.g., ±<NUM> degrees) and the tilt angles compared according to their signed values. In some embodiments, the processor may compare the subsequent accelerometer measurements with the initial accelerometer measurements obtained at the time of electric meter installation without calculating tilt angles. Threshold values may then be specified in terms of a difference in the accelerometer measurements rather than in terms of a tilt angle.

In response to determining that the tilt angles or acceleration measurements do not exceed the threshold value (<NUM>-N), the method may continue at block <NUM>. In response to determining that the tilt angles or acceleration measurements exceed the threshold (<NUM>-Y), at block <NUM>, a notification may be generated to the head-end system. The notification may be an alarm signal or other indication that the orientation of the electric meter has change beyond an allowable limit. The notification may include a timestamped event recorded in a memory location for example, in a location in the memory (e.g., the memory <NUM>) or in a register in the processor (e.g., the processor <NUM>) and an alarm flag set in a location in the memory or in a register in the processor.

It should be appreciated that the specific steps illustrated in <FIG> provide a particular method for measuring tilt of an electric meter installation according to an embodiment of the present disclosure. Other sequences of steps may also be performed according to alternative embodiments. For example, alternative embodiments may perform the steps outlined above in a different order. Moreover, the individual steps illustrated in <FIG> may include multiple sub-steps that may be performed in various sequences as appropriate to the individual step. Furthermore, additional steps may be added or removed depending on the particular applications. One of ordinary skill in the art would recognize many variations, modifications, and alternatives.

According to some aspects of the present disclosure, changes in electric meter orientation based on accelerometer measurements may be used to detect tampering with the meter. For example, in some cases, an electric meter may be powered down, carefully removed from its socket, and powered back up such that a typical accelerometer signal signature cannot be detected. Such a situation may occur when, for example, the electric meter is powered back up on a work bench during an attempt to illegally modify the meter. In such cases, the change in orientation of the electric meter detected in accordance with the present disclosure would be notified to the utility provider. For example, a change in any tilt angle exceeding the threshold value accompanied by a loss of voltage may indicate that the electric meter has been removed. The stored energy in the electric meter can provide sufficient power to transmit the notification of meter removal to the head-end system.

Claim 1:
A method comprising:
determining (<NUM>) an initial orientation of an electric meter (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) based on initial acceleration measurements from an accelerometer (<NUM>) positioned in the electric meter (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>);
continuously (<NUM>) monitoring subsequent acceleration measurements from the accelerometer (<NUM>);
determining (<NUM>) subsequent orientations of the electric meter (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) based on the subsequent acceleration measurements obtained within a specified period of time;
determining (<NUM>) differences between the initial orientation and the subsequent orientations based on the initial acceleration measurements and the subsequent acceleration measurements obtained within the specified period of time;
comparing the differences to threshold values;
determining (<NUM>) that the differences exceed the threshold values;
based on the differences exceeding the threshold values generating (<NUM>) a notification of a change in orientation of the electric meter (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) to a head-end system (<NUM>).