JP5102569B2 - Electricity meter - Google Patents

Description

  The present invention relates to a watt hour meter that measures the amount of power used by a customer, and more particularly to a technique for appropriately measuring the amount of power.

  Electricity meters attached to customers are verified at the Nippon Electric Meters Verification Laboratory to ensure the fairness of the metering. In this verification, the watt-hour meter is actually operated to measure the amount of power used, and whether or not the watt-hour meter operates correctly is checked.

  In the case of a watt-hour meter that does not require a transformer (hereinafter referred to as a “single meter”), in general, for example, as shown in FIG. Test terminals 1a and 1b for insulating a current circuit and a voltage circuit (both not shown) are provided in the terminal portion. FIG. 6 shows the terminal structure of a single-phase three-wire or three-phase three-wire single meter.

  FIG. 7 shows an electrical connection diagram of this single instrument. The 2S terminal on the power supply side is a neutral wire (ground) terminal, and is connected to the 2L terminal on the load side inside the single meter. The 1S terminal on the power source side is connected to the 1L terminal on the load side via the current coil 3a inside the single meter, and the neutral wire is connected via the connection piece 1a for testing and the voltage coil 2a inside the single meter. It is connected to the. Similarly, the 3S terminal on the power supply side is connected to the 3L terminal on the load side via the current coil 3b inside the single meter, and also via the test connection piece 1b and the voltage coil 2b inside the single meter. Connected to neutral wire.

  In the single instrument configured as described above, the test connection pieces 1a and 1b are set in an open state so as to disconnect the current circuit and the voltage circuit when performing the instrumental difference test. A short circuit is set to connect the circuit and the voltage circuit. By setting the test connection pieces 1a and 1b in a short-circuit state, the amount of electric power can be integrated in actual operation.

  On the other hand, in the case of a watt-hour meter combined with an instrument transformer (hereinafter referred to as “transformer meter”), the current circuit and voltage circuit (both not shown) of the watt-hour meter are originally electrically insulated, As shown in FIG. 8, no test connection piece is provided on the terminal portion. FIG. 8 shows a terminal structure of a single-phase three-wire type or three-phase three-wire type change instrument.

  FIG. 9 shows an electrical connection diagram of this variation instrument. The P2 terminal is a neutral wire (ground) terminal. The 1S terminal on the power supply side and the 1L terminal on the load side are connected to the secondary side terminal of the current transformer CT1, and supply a current converted to an appropriate magnitude to a current circuit (not shown). The 3S terminal on the power supply side and the 3L terminal on the load side are connected to the secondary terminal of the current transformer CT2, and supply the current converted to an appropriate magnitude to another current circuit (not shown) of the watt hour meter. To do.

  The P1 terminal is connected to a secondary terminal of an instrument transformer (not shown), and supplies a voltage converted to an appropriate magnitude to a voltage circuit (not shown). The P3 terminal is connected to the secondary terminal of the instrument transformer, and supplies a voltage converted to an appropriate magnitude to another voltage circuit (not shown) of the watt-hour meter. With such a configuration, the electric energy can be integrated inside the watt-hour meter.

  As such a watt-hour meter, Patent Document 1 discloses that a fastening screw for fixing a connecting member that connects an input terminal and a test terminal arranged for a performance test and an error test is caused by an illegal act or the like. An electronic watt-hour meter is disclosed that, when loosened, can notify abnormality and appropriately measure the amount of power used.

This electronic watt-hour meter detects the voltage at the input terminal and the test terminal with the voltage detection unit, calculates the respective effective value with the calculation unit, and the voltage with the respective effective value calculated with the determination unit in the calculation unit The difference is calculated, and a determination signal is output when the voltage difference is equal to or greater than a predetermined voltage. When the voltage difference between the input terminal and the test terminal is equal to or greater than a predetermined voltage, the second power calculation unit calculates the amount of power.
JP 2006-317166 A

  However, in a single meter, the voltage circuit and the current circuit should be used in a short-circuit state where the test connection pieces 1a and 1b are connected, but the test connection pieces 1a and 1b are disconnected and operated in an open state. There is a case.

  For example, there is a single-phase three-wire system as a method for supplying electricity to a general household. However, in the case of a single meter corresponding to this single-phase three-wire system, as described above, the voltage circuit and current circuit on one side are connected. The test connection piece 1a and the test connection piece 1b for connecting the three-side voltage circuit and current circuit are provided.

  In the case of an electronic watt hour meter, the operation power supply inside the watt hour meter is generally supplied from a voltage circuit on one side. Operation stops. When the three-side test connection piece 1b is not connected, the amount of power on the one side is measured, but the amount of power on the three side is not measured. Thus, when the test connection pieces 1a and 1b are not connected (opened), electricity can be supplied to the consumer, but the watt-hour meter integrates the amount of power according to the amount used. Can not do.

  In addition, the test connection pieces 1a and 1b are left unconnected (open state), and a certain period of time has passed. Thereafter, the test connection pieces 1a and 1b are returned to the original use state, that is, the short-circuit state in which the test connection pieces 1a and 1b are connected. If the terminal part of the watt-hour meter is difficult to see from the outside even if the open state continues, the test connection pieces 1a and 1b were disconnected for a certain period, that is, proper It is difficult for an electric power meter meter to detect that there is a period during which no measurement has been performed.

  On the other hand, in the conversion instrument, the secondary terminal of the instrument transformer (instrument transformer and current transformer) should be used in a state where the voltage circuit and current circuit of the watt hour meter are connected. As shown in FIG. 10, the connection between the secondary terminal of the instrument transformer or current transformer and the watt hour meter may be broken. Further, there is a case where a large impedance is included in the connection between the secondary terminal of the instrument transformer or the current transformer and the watt hour meter.

  In the case of a conversion instrument compatible with the three-phase three-wire system, which is a general electricity supply method, if the connection between the instrument transformer and the voltage circuit on the one side is broken, the amount of power is the same as for a single instrument. The metering operation stops. If a large impedance is included, the weighing operation may be performed, but proper weighing cannot be performed due to a voltage drop due to the impedance. Similarly, if the connection between the instrument transformer and the voltage circuit on the 3 side is broken, or if the connection between the current transformer and the current circuit on the 1 side or 3 side is broken, or Even when a large impedance is included between them, an appropriate weighing operation cannot be performed.

  Furthermore, even if the connection between the instrument transformer and the watt hour meter is broken or a large impedance is included between them, the connection between the instrument transformer and the watt hour meter is externally applied. When it is difficult to confirm, it is difficult for the meter reader of the electric power company to detect that there is a period in which proper measurement has not been performed.

  The subject of this invention is providing the watt-hour meter which can know easily whether the measurement of electric energy was performed appropriately.

In order to solve the above problems, the invention according to claim 1 detects the magnitude of the voltage of each input phase and outputs it as a voltage value, and detects the magnitude of the current and outputs it as a current value. The voltage / current detector and whether the voltage value sent from the voltage / current detector is within a predetermined range, whether the current value is within a predetermined range, and the unbalance obtained based on the current value of each phase A determination unit that determines whether the rate is equal to or less than a specified value, and a determination unit that determines that the voltage value has deviated from the predetermined range, a case in which it is determined that the current value has deviated from the predetermined range, or A notification unit for notifying that the measurement of the electric energy is not normally performed when it is determined that the unbalance rate has become larger than a specified value, and a clock mechanism for measuring the date and time, the notification The voltage value is determined by the determination unit When it is determined that the current value has deviated from the predetermined range, when it is determined that the current value has deviated from the predetermined range, or when it is determined that the unbalance rate has become larger than the specified value, the electric energy is measured. Is started, the determination unit determines that the voltage value is within the predetermined range, determines that the current value is within the predetermined range, and is unbalanced. Even if it is determined that the rate has fallen below a specified value, the notification is continued, and when the predetermined time has elapsed from the start of the notification by the clock mechanism, the notification is stopped, and the determination When it is determined by the unit that the voltage value has deviated from the predetermined range, and when it has been determined that the voltage value has departed from the predetermined range, the voltage value and the current value have been determined to have deviated from the predetermined range, and the predetermined range. Returned to The current value at the time of determination, and the unbalance rate when it is determined that the unbalance rate has become larger than the specified value and when the unbalance rate has returned to the specified value or less, A storage unit for storing together with the date and time counted by the clock mechanism, a communication unit for transmitting the date and time stored in the storage unit and at least one of an electric energy, a voltage value, a current value or an unbalance rate to the outside; It is characterized by providing .

  According to a second aspect of the present invention, in the first aspect of the invention, the notification unit includes a display unit that displays information related to the measurement of electric energy, and the determination unit determines that the voltage value has deviated from the predetermined range. When it is determined that the current value has deviated from the predetermined range, or when it is determined that the unbalance rate has become larger than the specified value, all or part of the information to be displayed flashes. And informing that the measurement of electric energy is not normally performed.

According to the invention of claim 1, for example, the test connection piece is opened in a single instrument, or the connection between the instrument transformer and the watt hour meter is disconnected in the modification instrument, When the voltage value deviates from the predetermined range, the current value deviates from the predetermined range, or the unbalance rate becomes larger than the specified value, a notification is made that the measurement of electric energy is not performed normally. Therefore, the meter reader of the electric power company can easily know whether or not the amount of electric power has been properly measured. In addition, when the voltage value deviates from the predetermined range, when the current value deviates from the predetermined range, or when the unbalance rate becomes larger than the specified value, a notification that the power measurement is not normally performed. Even if the voltage value returns to the predetermined range, the current value returns to the predetermined range, and the unbalance rate falls below the specified value, the notification is continued. Since it stops, the predetermined time is set larger than, for example, the meter reading period, so that the meter reader of the electric power company can surely recognize that the measurement of the electric energy has not been properly performed. The voltage value when the voltage value deviates from the predetermined range and when it returns, the current value when the current value deviates from the predetermined range and when it returns, and when the unbalance rate exceeds the specified value and The unbalance rate when it returns to below the specified value is stored together with the date and time, and the stored date and time and at least one of the electric energy, voltage value, current value, or unbalance rate are transmitted to the outside. It becomes possible to specify the boundary between a correct measurement value and an inappropriate measurement value, and it is possible to perform subsequent fee calculation smoothly.

  According to the second aspect of the present invention, the display unit is used as the notification unit, and the fact that the measurement of electric energy is not normally performed is notified by blinking all or part of the information to be displayed. The display unit originally provided in the watt hour meter can also be used as the unit. As a result, the watt-hour meter can be configured at low cost.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram illustrating the configuration of the watt-hour meter according to the first embodiment of the present invention. This watt-hour meter includes a voltage / current detection unit 10, a CPU (Central Processing Unit) 20, a display unit 30, and a communication unit 40.

  The voltage / current detector 10 detects the magnitude of the voltage of each phase of the three-phase AC power supplied from a power supply facility (not shown), outputs the voltage value, and the magnitude of the current of each phase of the three-phase AC power. Is detected and output as a current value. The voltage value and current value output from the voltage / current detector 10 are sent to the CPU 20.

  The CPU 20 executes predetermined processing based on the voltage value and current value sent from the voltage / current detection unit 10, and sends the result to the display unit 30 and the communication unit 40. Details of the CPU 20 will be described later.

  The display unit 30 includes, for example, an LCD (Liquid Crystal Display) or LED (Light Emitting Diode) display, and corresponds to the notification unit of the present invention. As shown in FIG. 2, the display unit 30 displays the meter reading date, the effective power amount for each time zone, the maximum demand power, or the like according to the data sent from the CPU 20. The display unit 30 causes the screen to blink in response to an instruction from the CPU 20.

  The communication unit 40 transmits the date and time sent from the CPU 20 and at least one of the electric energy, voltage value, current value, and unbalance rate (details of which will be described later) via a communication line (not shown) (monitoring). Device).

  Next, details of the CPU 20 will be described. The CPU 20 includes a determination unit 21, a power calculation unit 22, a clock mechanism 23, and a memory 24. The memory 24 includes an abnormal value memory 24a and a normal value memory 24b.

  The determination unit 21 determines whether the voltage value sent from the voltage / current detection unit 10 is within a predetermined range, whether the current value is within a predetermined range, and the current value of each phase. It is determined whether or not the obtained unbalance rate is equal to or less than a specified value. Here, the unbalance rate refers to the ratio of the antiphase component to the positive phase component of the three-phase current. The processing performed by the determination unit 21 will be described in detail later, but the following processing is generally performed.

  That is, the determination unit 21 determines that the voltage value sent from the voltage / current detection unit 10 does not deviate from the predetermined range, the current value does not deviate from the predetermined range, and the unbalance rate is equal to or less than a specified value. When it is determined that the voltage value and the current value are transmitted from the determination unit 21, the power calculation unit 22 is transmitted.

  The determination unit 21 determines that the voltage value sent from the voltage / current detection unit 10 has deviated from the predetermined range, determines that the current value has deviated from the predetermined range, or the unbalance rate. Is determined to be larger than the specified value, that is, when it is determined that the state has changed from the normal state to the abnormal state, the electric energy, voltage value, current value, and unbalance rate are sent to the abnormal value memory 24a. At the same time, the clock mechanism 23 is instructed to store the date and time, and the power calculator 22 is instructed to blink.

  Further, the determination unit 21 determines that the voltage value sent from the voltage / current detection unit 10 has returned to the predetermined range, determines that the current value has returned to the predetermined range, or the unbalance rate. When it is determined that has returned to the specified value or less, that is, when the abnormal state has changed to the normal state, the voltage value and current value sent from the voltage / current detector 10 are sent to the normal value memory 24b. The clock mechanism 23 is instructed to store the date and time.

  The power calculation unit 22 calculates power by multiplying the current value and voltage value sent from the determination unit 21, sends the power as the maximum demand power to the display unit 30, integrates the calculated power, and calculates the amount of power Is calculated and sent to the display unit 30 as the amount of active power. In addition, the power calculation unit 22 also performs control for blinking information displayed on the display unit 30 in accordance with an instruction from the determination unit 21.

  The clock mechanism 23 measures the date and time (date and time). The clock mechanism 23 sends the date and time at that time to the abnormal value memory 24a or the normal value memory 24b in response to an instruction from the determination unit 21.

  The abnormal value memory 24a receives the voltage value, current value, and unbalance rate sent from the determination unit 21 when the state changes from the normal state to the abnormal state, the date and time sent from the clock mechanism 23, and the power calculation unit 22. The amount of power is stored. In addition, the normal value memory 24b includes a voltage value, a current value and an unbalance rate sent from the determination unit 21 when the state changes from an abnormal state to a normal state, a date and time sent from the clock mechanism 23, and a power calculation unit. The amount of power from 22 is stored. The voltage value, current value, unbalance rate, and date / time stored in the abnormal value memory 24a and the normal value memory 24b are sent to the communication unit 40 at a predetermined timing.

  Next, the operation of the watt-hour meter according to the first embodiment of the present invention configured as described above will be described separately for the measurement value recording process and the abnormality notification process.

  FIG. 3 is a flowchart showing a measurement value recording process which is a part of the operation of the watt-hour meter according to the first embodiment of the present invention. In the measurement value recording process, first, the flag ER is cleared to zero (step S11). Here, the flag ER is used when the voltage value sent from the voltage / current detector 10 deviates from the predetermined range, when the current value deviates from the predetermined range, or when the unbalance rate becomes larger than the specified value. That is, it is set to “1” when an abnormal state occurs, the voltage value sent from the voltage / current detector 10 returns to a predetermined range, the current value returns to a predetermined range, and This flag is cleared to “0” when the unbalance rate returns to a specified value or less, that is, when it becomes normal.

  Next, measurement is performed (step S12). That is, the voltage / current detection unit 10 detects the magnitude of the voltage of each phase of the input three-phase AC power, and sends it to the determination unit 21 of the CPU 20 as a voltage value. The magnitude is detected and sent to the determination unit 21 of the CPU 20 as a current value.

  Next, the determination unit 21 checks whether or not the voltage value sent from the voltage / current detection unit 10 is within a predetermined range (step S13). If it is determined in step S13 that the voltage value is within the predetermined range, it is then checked whether the current value is within the predetermined range (step S14). That is, the determination unit 21 checks whether or not the current value sent from the voltage / current detection unit 10 is within a predetermined range.

  If it is determined in step S14 that the current value is within the predetermined range, then the determination unit 21 calculates and finds the unbalance rate based on the current value of each phase sent from the voltage / current detection unit 10. It is checked whether or not the obtained unbalance rate is equal to or less than a specified value (step S15). If it is determined in step S15 that the unbalance rate is equal to or less than the specified value, then the determination unit 21 checks whether the flag ER is set to “1” (step S16).

  If it is determined in step S16 that the flag ER is not “1”, that is, the voltage value, current value, and unbalance rate are all normal, the process returns to step S12 and the above-described processing is repeated.

  On the other hand, when it is determined in step S16 that the flag ER is “1”, the date and time and the measured value are stored (step S17). That is, the determination unit 21 recognizes that the normal state has been returned from the abnormal state, and sends the measured value (power amount, voltage value, current value, and unbalance rate) to the normal value memory 24b, and to the clock mechanism 23. To instruct memorizing the date and time. As a result, the date, power amount, voltage value, current value, and unbalance rate at the time of change from the abnormal state to the normal state are stored in the normal value memory 24b. Then, it returns to step S11 and a process is restarted from an initial state.

  In step S13, when it is determined that the voltage value is not within the predetermined range, that is, deviated from the predetermined range, the determination unit 21 then stores the voltage value sent from the voltage / current detection unit 10 last time and stored. Is in a predetermined range (step S18). If it is determined in step S18 that the previous voltage value is not within the predetermined range, it is recognized that the voltage value has deviated from the predetermined range, and the process returns to step S12 and measurement is performed again.

  On the other hand, if it is determined in step S18 that the previous voltage value is within the predetermined range, it is determined that the voltage value has deviated from the predetermined range at the time of the current process, and the flag ER is set to “1”. (Step S21). Next, the date and time and the measured value are stored (step S22). That is, the determination unit 21 recognizes that the state has changed from the normal state to the abnormal state, and sends the measurement value (power amount, voltage value, current value, and unbalance rate) to the abnormal value memory 24a, and to the timepiece mechanism 23. To instruct memorizing the date and time. As a result, the date, power amount, voltage value, current value, and unbalance rate at the time of change from the normal state to the abnormal state are stored in the abnormal value memory 24a. Thereafter, the process returns to step S12, and measurement is performed again in the abnormal state.

  When it is determined in step S14 that the current value is not within the predetermined range, that is, deviated from the predetermined range, the determination unit 21 then stores the current value sent from the voltage / current detection unit 10 last time and stored. Is in the predetermined range (step S19). If it is determined in step S19 that the previous current value is not within the predetermined range, it is recognized that the current value has deviated from the predetermined range, and the process returns to step S12 and measurement is performed again.

  On the other hand, if it is determined in step S19 that the previous current value is within the predetermined range, it is determined that the current value has deviated from the predetermined range at the time of the current process, and the flag ER is “1” as described above. "(Step S21), and then the date and time and the measured value are stored (step S22). Thereafter, the process returns to step S12, and measurement is performed again in the abnormal state.

  If it is determined in step S15 that the unbalance rate is not less than the specified value, that is, greater than the specified value, then the determination unit 21 then determines that the unbalance rate calculated and stored last time is less than or equal to the specified value. Whether or not (step S20). If it is determined in step S20 that the previous unbalance rate is not less than or equal to the specified value, it is recognized that the state where the unbalance rate is greater than the specified value is continued, and the process returns to step S12 and measurement is performed again.

  On the other hand, if it is determined in step S20 that the previous unbalance rate is less than or equal to the specified value, it is determined that the unbalance rate has become greater than the specified value at the time of the current process, and the flag ER is set as described above. “1” is set (step S21), and then the date and time and the measured value are stored (step S22). Thereafter, the process returns to step S12, and measurement is performed again in the abnormal state.

  Next, abnormality notification processing, which is another part of the operation of the watt-hour meter according to Embodiment 1 of the present invention, will be described with reference to the flowchart shown in FIG. This notification process is executed in parallel with the above-described measurement value recording process, but will be described as a process independent of the measurement value recording process for the sake of simplicity.

  In the abnormality notification process, first, measurement is performed (step S31). The process of step S31 is the same as the process of step S12 of the flowchart shown in FIG. Next, it is checked whether or not the voltage value is within a predetermined range (step S32). The process of step S32 is the same as the process of step S13 of the flowchart shown in FIG. If it is determined in step S32 that the voltage value is not within the predetermined range, that is, deviates from the predetermined range, the process proceeds to step S35.

  On the other hand, if it is determined in step S32 that the voltage value is within the predetermined range, it is then checked whether or not the current value is within the predetermined range (step S33). The processing in step S33 is the same as the processing in step S14 in the flowchart shown in FIG. If it is determined in step S33 that the current value is not within the predetermined range, that is, deviates from the predetermined range, the process proceeds to step S35.

  On the other hand, if it is determined in step S33 that the current value is within the predetermined range, it is then checked whether or not the unbalance rate is equal to or less than a specified value (step S34). The process of step S34 is the same as the process of step S15 of the flowchart shown in FIG. If it is determined in step S34 that the unbalance rate is not less than the specified value, that is, greater than the specified value, the process proceeds to step S35. On the other hand, if it is determined in step S34 that the unbalance rate is equal to or less than the specified value, the process returns to step S31 and the above-described processing is repeated.

  In step S35, a notification process is performed. That is, the determination unit 21 determines that the voltage value sent from the voltage / current detection unit 10 has deviated from the predetermined range, determines that the current value has deviated from the predetermined range, or the unbalance rate. Is determined to be larger than the prescribed value, that is, when it is determined that the state has changed from the normal state to the abnormal state, the power calculation unit 22 is instructed to blink. Receiving the instruction, the power calculation unit 22 instructs the display unit 30 to blink. Thereby, the information displayed on the display part 30 blinks. In this case, as shown in FIG. 2A, the entire display screen can be blinked. However, as shown in FIG. 2B, a part of the display screen is blinked. You can also.

  Next, by referring to the clock mechanism 23, it is checked whether or not a predetermined time has elapsed since the notification process (step S35) was executed (step S36). Here, the predetermined time can be equal to or longer than a cycle (for example, one month) in which the meter reader of the electric power company performs meter reading. If it is determined in step S36 that the predetermined time has not elapsed, the process returns to step S35 and the notification process is continued.

  On the other hand, if it is determined in step S36 that the predetermined time has elapsed, a notification stop process is performed (step S37). That is, the determination unit 21 instructs the power calculation unit 22 to stop blinking display. Receiving the instruction, the power calculation unit 22 instructs the display unit 30 to stop blinking display. Thereby, the blinking of the information displayed on the display unit 30 is stopped.

  According to the watt-hour meter configured as described above, operation as shown in FIG. 5 is possible. If the previous meter reading date is March 5, the measurement value at that time is 005683.9 kWh, an abnormality is detected on March 10, and the measurement value at that time is 000805.1 kWh, then from March 5 to March 10 The measured value 2401.2 kWh up to the day is determined to be an appropriate measured value, and a normal charge calculation is performed for the usage during that time.

  After that, when it returns to the normal state on April 4, and the measurement value at that time is 01434.34.3 kWh, the measurement value 6239.2 kWh from March 10 to April 4 is determined to be an inappropriate measurement value. In the meantime, usage during that period will be excluded from the fee calculation and subject to a penalty. Thereafter, if the current meter reading date is April 5, and the measured value at that time is 01484.4 kWh, the measured value 480.1 kWh from April 4 to April 5 is determined as an appropriate measured value, Normal charges are calculated for the usage during that time.

  As described above, according to the watt-hour meter according to the first embodiment of the present invention, for example, the test connection piece is opened in the single meter, or the meter transformer and the watt-hour meter are used in the variation meter. Measurement of electric energy when the voltage value deviates from the predetermined range, the current value deviates from the predetermined range, or the unbalance rate becomes larger than the specified value due to disconnection between the two. Is notified by blinking of the display screen of the display unit 30, the meter reader of the electric power company can easily know whether or not the measurement of the electric energy has been properly performed.

  In addition, when the voltage value deviates from the predetermined range, when the current value deviates from the predetermined range, or when the unbalance rate becomes larger than the specified value, a notification that the power measurement is not normally performed. The display screen of the display unit 30 continues to blink for a predetermined time even when the voltage value returns to the predetermined range, the current value returns to the predetermined range, and the unbalance rate falls below the specified value. The display screen stops blinking when the period of time elapses. Therefore, if the predetermined time is set to be longer than, for example, the meter reading period, the meter reader of the power company always sees the blinking of the display screen of the display unit 30 caused by the abnormality. be able to. As a result, the meter reader of the electric power company can reliably recognize that the measurement of the electric energy has not been properly performed.

  The voltage value when the voltage value deviates from the predetermined range and when it returns, the current value when the current value deviates from the predetermined range and when it returns, and when the unbalance rate exceeds the specified value and The unbalance rate when it returns to below the specified value is stored together with the date and time, and the stored date and time and at least one of the electric energy, voltage value, current value, or unbalance rate are transmitted to the outside. It becomes possible to specify the boundary between a correct measurement value and an inappropriate measurement value, and it is possible to perform subsequent fee calculation smoothly.

It is a block diagram which shows the structure of the watt-hour meter which concerns on Example 1 of this invention. It is a figure which shows the example of the display screen of the display part of the watt-hour meter which concerns on Example 1 of this invention. It is a flowchart which shows the recording process of the measured value which is a part of operation | movement of the watt-hour meter which concerns on Example 1 of this invention. It is a flowchart which shows the alerting | reporting process of abnormality which is another part of operation | movement of the watt-hour meter which concerns on Example 1 of this invention. It is a figure for demonstrating the operation example of the watt-hour meter which concerns on Example 1 of this invention. It is a figure which shows the terminal structure of the conventional single-phase three-wire type or three-phase three-wire type single meter. It is a figure which shows the electrical connection of the conventional single-phase three-wire type or three-phase three-wire type single meter. It is a figure which shows the terminal structure of the conversion instrument of the conventional single phase 3 wire type or a 3 phase 3 wire type. It is a figure which shows the electrical connection of the conventional single-phase three-wire type or three-phase three-wire type change instrument. It is a figure for demonstrating the abnormal state of the conventional single-phase three-wire type or three-phase three-wire type change instrument.

Explanation of symbols

10 Voltage Current Detection Unit 20 CPU
21 Determination unit 22 Power calculation unit 23 Clock mechanism 24 Memory 24a Abnormal value memory 24b Normal value memory 30 Display unit,
40 Communication Department

Claims (2)

A voltage / current detector that detects the magnitude of the voltage of each input and outputs it as a voltage value, and detects the magnitude of the current and outputs it as a current value;
Whether the voltage value sent from the voltage / current detector is within a predetermined range, whether the current value is within a predetermined range, and the unbalance rate determined based on the current value of each phase is below a specified value A determination unit for determining whether or not
When the determination unit determines that the voltage value has deviated from the predetermined range, it has been determined that the current value has deviated from the predetermined range, or it has been determined that the unbalance rate has become larger than the specified value. A notification unit for notifying that the measurement of electric energy is not normally performed,
With a clock mechanism that measures the date and time,
The notifying unit determines that the voltage value has deviated from the predetermined range by the determining unit, or has determined that the current value has deviated from the predetermined range, or the unbalance rate becomes greater than a specified value. When it is determined that the measurement of power is not properly performed,
Even if the determination unit determines that the voltage value is within a predetermined range, determines that the current value is within the predetermined range, and determines that the unbalance rate is equal to or less than a specified value. , Continue the notification,
When it is timed that a predetermined time has elapsed from the start of the notification by the clock mechanism, the notification is stopped,
When the determination unit determines that the voltage value has deviated from the predetermined range, and when it has been determined that the voltage value has departed from the predetermined range, It was determined that the current value when it was determined that it had returned to the predetermined range, and that the unbalance rate was greater than the specified value, and that the unbalance rate had returned to the specified value or less. A storage unit for storing the unbalance rate of time together with the date and time counted by the clock mechanism;
A watt hour meter comprising: a communication unit that transmits the date and time stored in the storage unit and at least one of an electric energy, a voltage value, a current value, or an unbalance rate to the outside .   The notification unit includes a display unit that displays information related to measurement of electric energy. When the determination unit determines that the voltage value has deviated from the predetermined range, it is determined that the current value has deviated from the predetermined range. If it is determined that the unbalance rate has become larger than the specified value, all or part of the information to be displayed blinks to notify that the measurement of power is not performed normally. The watt-hour meter according to claim 1.

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