JP2010038716A - Measurement output apparatus and electric energy measuring system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measurement output apparatus capable of detecting, comparing, and computing at least two substantially instantaneously measurable physical quantities, performing prescribed output processing, and being also used for determining incorrect connections, for example, in power distribution. <P>SOLUTION: The measurement output apparatus includes: at least two physical quantity detection means capable of continuously measuring substantially instantaneously measurable physical quantities; a signal processing means for periodically sampling output signals from each physical quantity detection means at prescribed time intervals to acquire instantaneous values; a computation control means for comparing and computing time-serially acquired instantaneous values or the amount of change of the instantaneous values with at least the detection means synchronized with one another; and an output means for performing prescribed output processing when results of the comparison and computation are provided with prescribe conditions. An electric energy measuring system includes the function of the measurement output apparatus. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention mainly measures and acquires at least two physical quantities that can be measured substantially instantaneously, such as current, compares these measurement results and / or their calculation results, and provides a predetermined condition when a predetermined condition is satisfied. The present invention relates to a measurement output device that can output a signal and a power metering system having the function of the measurement output device.

  In the current electricity billing system, in addition to the existing power load facilities, the electricity customers are charged with midnight power load equipment (hereinafter referred to simply as midnight power) such as night heat storage devices, off-peak heat storage electric water heaters, and energization controlled heat storage devices. In the case of newly establishing a load), it is necessary to determine the amount of power used in each of the preset time zones of night and daytime. In order to determine the amount of power used in each time zone, a method of replacing an existing watt hour meter with a watt hour hour meter is used, or, as shown in FIG. A method is adopted in which the switch 32 and the watt-hour meter 34 for measuring midnight power are connected in parallel.

  In the latter case, the time switch 32 and the midnight power metering watt-hour meter 34 are on the power source side of the watt-hour meter 30 for the light load, and are in the middle of the power lines 46 and 47 laid for the midnight power load from the power lines 40 and 42. Connected in series. The time switch 32 is a device that includes a timer (not shown) and a switch S that is controlled to open and close by the timer. The switch S is closed for a preset time in the timer, and the power lines 48 and 49 are energized. It is comprised as follows.

However, when the watt-hour meter 34 and the time switch 32 are newly provided in the existing watt-hour meter 30 as described above, there are circumstances such as complicated power lines around these installation positions. The connection may be wrong. FIG. 9 is a connection diagram illustrating an example of erroneous connection of power lines in the same configuration as that illustrated in FIG. 8. In the example shown in this figure, the power lines 46 and 47 are branched from the load-side power lines 43 and 45 of the watt-hour meter 30, respectively. As a result, the internal switch S in the time switch 32 is closed for a predetermined set time. The amount of power consumed there during energization of the power load (hereinafter referred to as midnight power amount) is not only measured by the watt hour meter 34 but also added to the lamp load by the watt hour meter 30. It will be weighed twice. If misconnections that cause this double weighing are not found in various tests at the time of establishment of a midnight power load, a situation may occur in which the misconnections are not discovered over a long period of time. For this reason, there is a demand for the development of a device that can easily and reliably determine such an erroneous connection.
JP-A-11-108973 JP 2000-155142 A

  In view of the above circumstances, the present invention can detect and compare at least two physical quantities that can be measured substantially instantaneously, perform a predetermined output process, and can be used for, for example, determination of erroneous connection in the power distribution. It aims at providing a measurement output device.

  According to one aspect of the present invention, the object is to provide at least two physical quantity detection means for continuously detecting a physical quantity that can be measured substantially instantaneously, and output signals from the respective physical quantity detection means for a predetermined period of time. Signal processing means for obtaining an instantaneous value by sampling periodically at intervals, and an arithmetic control means for comparing and calculating at least the detection means in synchronism with the instantaneous value obtained in time series or the amount of change of the instantaneous value And an output means for performing a predetermined output process when the result of the comparison operation has a predetermined condition.

  The measurement output device of the present invention is configured to compare at least two substantially instantaneously measurable physical quantities detected as described above in synchronization, and to perform output processing according to the result. The physical quantity in the present invention is not particularly limited as long as it can be measured substantially instantaneously and is a known one. For example, current, voltage, power, magnetism, force, displacement, position, velocity, acceleration, angular velocity, rotation Number, distance, light, temperature, radiation, flow rate, etc. are included. As the physical quantity detection means in the measurement output device of the present invention, those capable of detecting any of these physical quantities and outputting an electrical signal corresponding to the magnitude can be used. In the measurement output device of the present invention, at least two physical quantity detection means are used, but the physical quantity detected by each may be the same or different from the physical quantities exemplified above. Also, the electrical signals output from the physical quantity detection means may be the same type or different types. Such electrical signals include, for example, analog current signals or voltage signals.

  Further, the signal processing means includes not only one that obtains an instantaneous analog signal obtained by sampling, but also one that has a function of analog-to-digital conversion of the instantaneous analog signal. Further, the change amount of the instantaneous value in the arithmetic control means indicates the difference between the instantaneous values before and after a predetermined elapsed time. Further, the output means includes one that has a visual or auditory display output, one that appropriately outputs a predetermined signal by wire or wireless to an external device, or a combination of both.

  According to another aspect of the present invention, the object is also applied to the power line, and at least two current detection means that are installed in a power line constituting the power line and continuously detect a current flowing through the power line. A voltage detection means for detecting a line voltage to be detected, an electric energy metering mechanism for calculating an electric energy by appropriately using an electric signal from each of the detection means, and an electric signal from the current detection means at predetermined time intervals, respectively. Signal processing means for obtaining an instantaneous value by periodically sampling at the same time, and an arithmetic control means for performing a comparison operation in synchronism between at least the current detection means with respect to the instantaneous value obtained in time series or the amount of change of the instantaneous value And an output means for performing a predetermined output when the comparison calculation result has a predetermined condition together with or separately from the electric energy measurement result. It is achieved by the stem.

  According to the measurement output device of the present invention, it is possible to detect at least two physical quantities that can be measured substantially instantaneously by setting in advance what kind of comparison calculation is performed according to the purpose and application of the use, A detection result and / or a calculation result using the detection result are compared, and a predetermined output process can be performed when the comparison calculation result has a predetermined condition.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following drawings, the same or common parts are denoted by the same reference numerals, and redundant description is omitted below.

[Measurement output device]
FIG. 1 is a perspective view of a current measurement output device as an embodiment of the measurement output device of the present invention. As shown in FIG. 1, the measurement output device 1 according to the present embodiment includes 3 as current detection means connected to the device main body 10 via the device main body 10 and signal lines 15 a to 15 c drawn from the side surfaces thereof. Each of which is fixed to, for example, the front face of a terminal block of the watt hour meter, and is mainly used for determination of misconnection of a power line including the watt hour meter. It can be used.

  The apparatus main body 10 in the measurement output apparatus 1 of the present invention is a substantially rectangular parallelepiped box elongated in one direction. FIG. 2 shows a front view and a rear view, respectively. As shown in this figure (a), a display window 11 provided in part of the output means capable of display output is exposed in the central area of the front surface of the display window 11. Near both ends, through holes 10a and 10b that penetrate from the front surface to the back surface are formed. These through holes 10a and 10b are used for mounting and fixing the watt-hour meter 30 (which may be the watt-hour meter 34) with the rear surface of the apparatus main body 10 in contact with the front surface of the terminal block. Specifically, these two through holes 10a and 10b are respectively aligned with screw holes drilled near the both ends of the terminal arrangement direction of the terminal block of the watt-hour meter 30, and long screws (not fixed) are inserted into the through holes 10a and 10b. The device main body 10 is mounted and fixed on the front surface of the terminal block by inserting the screw into the screw holes.

  As shown in FIG. 2B, when the main body 10 is fixed to the front surface of a terminal block of a watt hour meter (not shown), the two terminals on the power supply side in the terminal block are provided on the rear surface of the apparatus main body 10. Contact terminals 17 and 18 are provided at predetermined positions so as to be able to contact the front surface. By bringing these contact terminals 17 and 18 into contact with two terminals of the terminal block, the measurement output device 1 of the present invention is configured to receive the drive power supply via these terminals.

  FIG. 3 is a block diagram showing the internal configuration of the apparatus main body 10. As shown in this figure, the apparatus main body 10 supplies power to the arithmetic means 25 from the signal processing means 22 to 24, the arithmetic control means 25, the setting input means 26, the output means 27, and the contact terminals 17 and 18. The power supply line 28 is built in. In addition to these, known means having other functions may be included.

  The signal processing means 22 to 24 are usually configured to include at least a sample and hold circuit unit and an analog / digital conversion circuit unit (both not shown in FIG. 4). The sample-and-hold circuit unit receives a control signal at a constant time interval from the arithmetic control means 25 described later, and holds the instantaneous value of the current signal flowing through the signal lines 15a to 15c at that time. While the sample-and-hold circuit section is not receiving the control signal, the sample-and-hold circuit section is maintained in a short-circuited state so that the ends of the signal lines 15a to 15c drawn therein are not opened. It is assumed that the electric signal from 13 or 14 is not input, and the configuration is such that the electric signal is input only when the control signal is input. The held current signal is sent to the analog / digital conversion circuit unit, where it is converted into a digital signal, and the digital signal (hereinafter referred to as an instantaneous value digital signal) is sent to the subsequent arithmetic control means 25.

  As shown in FIG. 3, the arithmetic control unit 25 includes a signal transmission system 251, a storage unit 252, and an arithmetic control circuit 253. Here, the signal transmission system 251 has a bidirectional or unidirectional signal transmission function between the storage unit 252 and the calculation control unit 253 and the external signal processing units 22 to 24, the setting input unit 26, and the output unit 27. Can be provided. Further, when other circuit units and means exist inside and outside the arithmetic control unit 25, signals may be transmitted to these circuit units and means in both directions or in one direction. Here, the signals include not only instantaneous digital signals from the signal processing means 22 to 24 and control signals from the arithmetic control circuit 253, but also output signals sent from the arithmetic control means 25 to the output means 27.

  The storage unit 252 stores a program of measurement procedures and arithmetic processing procedures of the measurement output device 1 of the present embodiment, and various setting values input from the setting input unit 26 described later and the signal processing units 22 to. Instantaneous digital signals from 24 are stored in time series. The storage unit 252 includes an area in which the former program and the latter instantaneous digital signal can be stored separately, or can be configured by a combination of two separate memories.

  The arithmetic control circuit unit 253 performs various arithmetic processes to be described later based on a program stored in the storage unit 252, and also includes internal circuit units, external signal processing units 22 to 24, an output unit 27, and the like. Control the operation of each means. Control signals for sampling are issued to the signal processing means 22 to 24 at predetermined time intervals. The timing of sending the control signal can be appropriately set from setting input means 26 described later. The calculation control means 25 outputs a predetermined signal to the output means 26 described later when this calculation result has a predetermined condition.

  The setting input means 26 is for inputting programs and various setting values necessary for measurement and calculation of the device 1 of the present embodiment. For example, an interface device that can be connected to a keyboard or other external device by wire or wirelessly. Etc. are included. The various settings in the previous period include, for example, setting of one or two or more time zones such as a night time zone (start time and end time), setting of sampling times in the signal processing means 22 to 24, and the like.

  Setting values, programs, and the like set and input via the setting input means 26 in the arithmetic control means are stored in the storage unit 252 of the internal arithmetic control means 25 via the interface device 26. Further, a button or the like may be arranged on the front surface or side surface of the apparatus main body 10 so that the setting value can be directly input. In this case, for example, the user's convenience can be improved by displaying a setting screen created in advance on the display window 11 of the apparatus body 10.

  The output means 27 is configured to perform output processing in a predetermined format by receiving the input of the predetermined signal. Although the output format is not particularly limited, in the present embodiment, the display window 11 provided on the front surface of the apparatus main body 10 is not only displayed with predetermined character information, but also, for example, wired or wireless to a separate apparatus. And a signal transmission means capable of transmitting a predetermined signal.

  In FIG. 1, CTs 12 to 14 each show a through shape having an annular outer shape (round window) with a circular through hole at the center, but the shape and type are not limited. For example, even though it is a through-type CT, the central through-hole can be used with a square shape (square window) or other shape, and the annular portion is divided into two or more by a radial dividing surface. Possible split types can also be used. A rod CT or primary side conductor in which a primary conductor such as a bus bar or an electric wire is passed through and fixed in advance in a through hole is wound in a coil shape around an iron core inside the container, and the primary provided on the outer surface of the container A wire-wound CT in which an electric wire constituting the circuit to be measured and a secondary signal line are connected to the terminal and the secondary terminal, respectively, can also be used. When a load current flows through the primary power line in CT12 to CT14, a small force current signal proportional to the magnitude of the load current is generated.

  The small force current signals are sent to the signal processing means 22 to 24 in the apparatus main body 10 through the secondary signal lines 15a to 15c, respectively. There is no restriction | limiting in particular as these signal wire | line 15a-15c, A well-known covered electric wire etc. can be used. The lengths of the signal lines 15a to 15c can be set as appropriate in consideration of their handling on site and the place of use of the first embodiment. Further, for example, a current or voltage converter may be provided in the middle of the signal lines 15a to 15c.

  Next, referring to FIG. 4 showing a case where the measurement output device 1 of the present embodiment is attached to the conventional general power metering system shown in FIG. The operation will be described. As shown in FIG. 4, the measurement output device 1 of the present embodiment is attached to a terminal block of a watt-hour meter for a light load in a conventional energy metering system. Three CT12-14 in the electric current measurement output device 1 of this embodiment are installed by the normal method in the electric power lines 43 and 45 for electric lamp loads, and the electric power line 50 for midnight electric power branches branched from now. Each CT can be installed on any of these power lines, but in FIG. 4, CT 12 is installed on the power line 50 and CT 13 and 14 are installed on the power lines 43 and 45, respectively.

  In general, in a power circuit having both an electric light load and a midnight power load as shown in FIG. 8, midnight power when there is a misconnection and when there is no normal connection (no misconnection). The trend of daily power consumption of load and lamp load shows different trends. FIG. 10 shows an example of changes in daily power consumption in the case of normal connection (see (a) in the figure) and in the case of incorrect connection (see (b) in the same figure). In addition, FIG. 11 is an enlarged view of the transition of the power usage of both loads before and after the time when supply of midnight power to the midnight power load is started at 23:00 in the graph of FIG. It is shown. When the connection of the power line to these devices is normal, as shown in FIG. 10 (a), there is almost no lamp load in the night time zone (in the figure, the time zone between 1 and 6 o'clock). Although the power consumption is greatly reduced due to the operation not being performed, the midnight power load is operated, and thus the midnight power amount tends to exceed the lamp load power amount during the same time period.

On the other hand, when double weighing occurs due to incorrect connection, in the transition of daily light load power and midnight load power,
(1) When the supply of midnight power to the midnight power load is started at 23:00, as shown in FIG. Ascending fluctuation corresponding to the increase in power consumption occurs,
(2) As shown in FIG. 10 (b), in the night time zone, the lamp load power is continuously larger than the midnight load power.
It shows a different tendency from the case of normal connection.

  Therefore, it is possible to determine a misconnection by detecting the used power and comparing the reduction (1), (2), or both of the used power of the electric light load and the late-night power load and the transition thereof. Can do. In addition, since it is normal that an equivalent voltage is applied between the power line for the midnight power load and the power line for the lamp load, the current flowing through these loads, not the power used, is detected and compared. By calculating, it becomes possible to determine the erroneous connection similarly.

  FIG. 5 is a flowchart for explaining the operation of each component in the measurement output device 1 of the present embodiment. In order for the measurement output device 1 of this embodiment to operate according to this flowchart, the current from the secondary side of each CT12-14 installed in each power line (43, 45, 50) leading to the lamp load and the midnight power load. It is assumed that a signal is sent to the apparatus main body 10 via the signal lines 15a to 15c.

  In the daytime, electrical signals from the secondary side of the two CTs 13 and 14 installed on the power line for the lamp load are input to the measurement output device 1 via the signal lines 15b and 15c. Since the 32 internal switches S are opened and the power lines 48 and 49 for the midnight power load are not energized, the electrical signal from the CT 12 is not input. In this case, in the measurement output device 1, the control signal is sent from the arithmetic control means 25 to each signal processing means 22 to 24 at a predetermined time interval or is not sent (by the measurement output device 1, these are set). Can be selected (so that no electrical signal is acquired). In the former case, the instantaneous digital signals output from the signal processing means 23, 24 may be stored in the arithmetic control means 25, extracted, averaged, and displayed on the display window 11 in the output means 27.

  Next, when the preset time of night comes, the switch S inside the time switch 32 is closed (S2), so that the midnight power load can be energized through the power lines 48 (50) and 49 (51). It is said. In this case, when a control device (such as a switch) that activates the midnight power load is separately connected to the power lines 48 (50) and 49 (51), the operation starts from the control device to the midnight power load. In particular, when such a control device is not provided on the power line, power supply to the midnight power load is started directly.

  When energization of the midnight power load is started, the load current flowing through the power lines 50 and 51 is detected by the CT 12, and a small force current signal proportional to the detected current is sent from the secondary side of the CT 12 to the signal processing means 22. . This current signal is digitally converted after being sampled at a predetermined timing in the signal processing unit 22 in the same manner as the other signal processing units 23 and 24, and the obtained instantaneous digital signal is correlated with the sampling time and the arithmetic control unit 25. And stored in a predetermined area of the storage unit 252.

  In the arithmetic control means 25, an instantaneous digital signal (hereinafter referred to as “instantaneous digital signal”) stored in time series in another storage area of the storage unit 252 according to a program procedure stored in advance in the internal storage unit 252. The value is sometimes referred to as “value”.) Is extracted in synchronization with each of CT12 to 14 and the following two comparison calculation processes are performed.

(1) Comparison of changes in lamp load current and midnight power load current at the start of midnight power load The midnight power load current is obtained from the instantaneous digital signal stored in time series in the storage unit 252 via the signal processing means 22. First, the time point at which the CT 12 detects and the transmission of the secondary current signal is started (this time point is referred to as “t ₀ ”) is determined, and the instantaneous value In (t ₀ ) of the midnight power load current at that time point is determined. The instantaneous value Id (t ₀ ) of the lamp load current is extracted from the storage unit 252 (S4). The instantaneous value Id (t ₀ ) of the lamp load current can be used by extracting either the current signal from CT 13 or the current signal from CT 14 from the storage unit 252, or averaging after extracting both A signal obtained by calculation can also be used.

Thus, the instantaneous value In (t ₁ ) of the midnight power load current and the instantaneous value of the lamp load current at a time point after a lapse of a preset minute time from the detection time point t ₀ (this time point is referred to as “t ₁ ”). The value Id (t ₁ ) is similarly extracted from the storage unit 252 (S5). As the instantaneous value Id (t ₁ ) of the lamp load current, a current signal from any one of the CTs 13 and 14 or a signal obtained by averaging is used in the same manner as the instantaneous value Id (t ₀ ). Can do. Substituting the instantaneous values extracted from the storage unit 252 in steps S4 and S5 into the following equation, the difference in the amount of change between the lamp load Id and the midnight power load current In at time (t ₁ -t ₀ ) is obtained (S6). ). In Equation 1 below, ΔIn and ΔId are the midnight power load current and the lamp load current increase at time (t ₁ -t ₀ ) (the midnight power increase D1 and the lamp load power in FIG. 11). (Corresponding to increase D2).

  A determination is made as follows depending on whether the calculation result of Equation 1 is about 0 (S7). Whether or not it is “about 0” is determined in advance by setting an arbitrary range including 0 in the setting input means 26 and storing it in a predetermined area of the storage unit 252, and whether or not the calculation result belongs to this range. Judgment should be made.

  When the calculation result is not 0 (ΔIn = D1 ≠ D2 = ΔId), it is determined that the connection is normal, and the calculation process by the calculation control unit 25 ends. On the other hand, when this calculation result is determined to be 0 (ΔIn = D1≈D2 = ΔId), the increase amount D1 and the increase amount D2 are substantially equal as shown in FIG. It is determined that there is a high possibility that the midnight electric energy is measured twice in total 30 and 34, respectively.

(2) Comparison of the lamp load current and the midnight power load current during the midnight power load operation time Next, in the case of the latter ΔIn≈ΔId, the times t ₁ and t sequentially stored in the predetermined areas of the storage unit 252 respectively. _{2, t} 3, · · ·, the instantaneous value of peak electricity load current at _{t i} (hereinafter, an in (. represented by _{t k))} and instantaneous value of the lamp load current (hereinafter, represented by Id _{(t k).} ) Are extracted in synchronization with each other, and the magnitudes of the two are compared (S8). As a result, when the former is equal to or greater than the latter, that is, when the condition of In (t _k )> = Id (t _k ) is satisfied, the instantaneous value In (t _k ) of the midnight power load current is zero. The process proceeds to step S11 to determine whether or not, otherwise, a control signal is output so that the output means 27 performs a predetermined output process (S10). After outputting this control signal, the process proceeds to step S11 in the same manner as described above, and when it is determined that the instantaneous value In (t _k ) of the midnight power load current is 0, the arithmetic processing by the arithmetic control means 25 is performed. finish.

  In the output means 27 that receives the control signal from the arithmetic control means 25, for example, as shown in FIG. 2 (a), for example, the characters “confirmation required” are displayed on the display unit (display window) 11 on the front surface of the apparatus body 10, for example. A predetermined output process is performed such as This output process includes, for example, outputting a predetermined signal in a wired or wireless manner to an external monitoring device, for example, in addition to or instead of the display output.

In FIG. 5, when the midnight power load current detection time (t ₀ ) determined in step 4 belongs to another preset time zone, for example, a message such as “microcomputer type confirmation” is displayed on the output means. It can also be configured to be displayed on the part. With such a configuration, it is confirmed that the water heater is a microcomputer type at the time of monthly meter reading etc. by displaying that the midnight power load is energized to a device such as a microcomputer type water heater. As a result, it is possible to accurately calculate the electricity bill taking into account the discount. The message on the display unit 11 is preferably displayed, for example, inside the measurement output device 1 or until an appropriate reset is applied from the outside.

  Further, in order to ensure the processing of each step in the flowchart, each step from S1 to S11 can be repeated a plurality of times by a known method. That is, since the steps of S1 to S11 usually cycle one cycle per day, monitoring is performed for several days to improve the reliability of the output processing of the measurement output device 1. The number of repetitions can be set as appropriate from the setting input means 26.

  As described above, according to the measurement output device of the present invention, at least two of the same or different physical quantities are detected, an instantaneous value is obtained by signal processing, the instantaneous value is compared for each detection means, and the calculation is performed. When the result has a predetermined condition, a predetermined output process can be performed.

[Electricity metering system]
FIG. 6 is a connection diagram showing an embodiment of the power metering system of the present invention partially including the configuration of the current measurement output device for erroneous connection determination shown in the embodiment. In this figure, the watt-hour meter system shown in this figure is a voltage that draws the line voltage of the power lines 40 to 42 for the lamp load into the watt-hour meter 2 together with three CTs 12 to 14 as current detection means. This is a transformer combination type in which signal lines (voltage detection means) 55 to 57 can be electrically connected to each other.

  One end of each of the voltage signal lines 55 to 57 is connected to each of the power lines 40 to 42 connected to the lamp load, and CTs 13 and 14 are installed on the power lines 40 and 42, respectively. The other ends of the current signal lines 15b and 15c drawn from the secondary sides of the two CTs 13 and 14 are connected to the terminal block of the watt-hour meter 2 together with the other ends of the voltage signal lines 55 to 57, and A voltage signal and a current signal are supplied into the watt-hour meter 2.

  Further, power lines 46 and 47 are branched from the power lines 40 and 42, and the branched power lines 46 and 47 are connected to the power supply side terminal of the terminal block of the time switch 32. One end of the power lines 48 and 49 is connected to the load side terminal of this terminal block, and the other end is connected to the midnight power load (or its control and monitoring device). CT12 is installed in the power line 48, and the other end of the current signal line 15a drawn from the secondary side is connected to the terminal block of the watt-hour meter 2.

  As shown in FIG. 6, the watt-hour meter 2 includes a power metering mechanism (not shown) that obtains the power consumption of the lamp load and the midnight power load based on the input current signal and voltage signal, respectively. ) Is built-in. The current signal and voltage signal may be either digital or analog. In addition, the watt-hour meter 2 processes the electrical signals of CT12 to 14 in the same manner as the measurement output device 1 described above, and compares the two to perform predetermined output processing when the two are compared and calculated. Is configured to do. FIG. 7 is a block diagram showing an example of an internal configuration of a watt-hour meter having such a function. In this figure, reference numerals 55 to 57 denote voltage signal lines. If necessary, the voltage signal lines 55 to 57 can be provided with a required number of single-phase or three-phase instrument transformers 54 in the middle thereof.

  As shown in FIG. 7, the current signals flowing through the current signal lines 15a to 15c are directly sampled and digitally converted by the signal processing means 22 to 24, and stored in a storage unit (not shown, FIG. 3, reference numeral 252) in the arithmetic control means 25. Stored in the reference). The signal processing means 22 to 24 may convert the current signals into voltage signals using a known current / voltage converter and input the voltage signals. Thereafter, in accordance with the program procedure stored in advance, the digital data of the instantaneous current value is extracted from the storage unit 252 and sent to the calculation control circuit unit, where it is used for calculation processing. When the calculation processing result includes a predetermined condition input from the setting input unit 26, the calculation control unit 25 issues a predetermined signal to the output unit 27 so that predetermined output processing is performed there. It is configured. A power supply line 59 for supplying power to the arithmetic control means 25 and the electric energy measuring means 60 is branched from predetermined two lines of the voltage signal lines 55 to 57.

  In the configuration of FIG. 6, the output unit 27 is configured to be able to output the calculation results of both the calculation control unit 25 and the electric energy measuring unit 60. Such an output unit 27 includes a display unit disposed on the front surface of the watt-hour meter 2, and can be configured to be communicable with an external device by wire or wirelessly. Further, the display unit provided in the output means 27 may be configured to include two display windows capable of displaying the lamp load power amount and the midnight power load power amount which are the calculation results, respectively, or one The display window may be configured so that the display of these electric energy is cyclically switched every predetermined time. Note that the output means is not limited to one that can be visually or audibly displayed and output as described above, and can output a predetermined signal as appropriate to an external device by wire or wireless, or both. It may be provided with a mechanism.

  According to the configuration of the power metering system of this embodiment, it is possible to obtain a power metering system that not only displays the lamp load power amount and the midnight power load power amount, but also has a function of determining a misconnection. Can do. In the electric energy metering system of the present invention, for example, the current detecting means and the voltage detecting means may be built in the apparatus main body of the watt hour meter.

  The measurement output device of the present invention is not limited to the embodiment in which the physical quantity is a current, and can be similarly applied to various known physical quantities. Examples of such known physical quantities include the current, voltage, power, magnetism, force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, temperature, radiation, and flow rate. Each of the at least two detection means in the measurement output device of the present invention may be one capable of detecting the same or different physical quantity among these physical quantities and outputting an electrical signal corresponding to the magnitude.

  As the physical quantity detection means, a sensor capable of measuring the physical quantity substantially instantaneously can be used. For example, a voltage transformer (PT) for voltage, a power meter for power, and a magnetic sensor for magnetism can be used. Also, for force, strain gauge, load cell, semiconductor pressure sensor, etc .; for displacement, potentiometer, differential transformer, rotation angle sensor, linear encoder, rotary encoder, etc .; for position optical position sensor (PSD), for speed, tachometer , Laser Doppler vibrometer, laser Doppler velocimeter, etc .; acceleration sensor, earthquake sensor, etc .; angular velocity, gyro sensor, etc .; rotation speed, tachometer, rotary encoder, etc .; distance, ultrasonic rangefinder, static Examples include capacitance displacement gauges. In addition, for light quantity, light sensor, photoelectric element, photodiode, etc .; For temperature, contact temperature sensor such as thermistor, thermocouple, etc., non-contact temperature sensor such as radiation thermometer, etc .; For concentration in gas or liquid, ion concentration , Gas concentration; for radiation, proportional counter, scintillation detector, Geiger-Muller counter, semiconductor detector, thermoluminescence dosimeter, Cherenkov counter, etc .; for flow, venturi flowmeter, orifice flowmeter, laminar flow Meter, hot-wire flow meter, Karman vortex flow meter, ultrasonic flow meter, electromagnetic flow meter and so on. In addition, by setting in advance via the setting input unit according to the type of the physical quantity, a predetermined output process can be performed by the output unit.

It is a perspective view which shows the external appearance of one Embodiment of the measurement output device of this invention. It is the front view and back view of an apparatus main body of embodiment shown in FIG. It is a block diagram which shows the internal structure of the measurement output device shown in FIG. It is a figure which shows the mounting state to the electric energy metering system of the measurement output device shown in FIG. It is a flowchart which shows operation | movement of the internal structure of the measurement output device shown in FIG. It is a figure which shows one Embodiment of the electric energy metering system of this invention. It is a block diagram which shows the internal structure of the electric energy metering system of this invention. It is a figure which shows an example of the conventional electric energy metering system. It is a figure which shows an example of the misconnection of the feeder line which can generate | occur | produce in the electric energy metering system shown in FIG. It is a graph which shows transition of the daily electric power consumption which used the electric energy metering system shown in FIG. 8 and FIG. It is an enlarged view which shows transition of the electric power used of the lamp load and the midnight electric power load in the graph of FIG.10 (b), respectively.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Measurement output device 2 Electric energy measuring system 10 Main body 10a, 10b Screw insertion hole 11 Display window 12, 13, 14 CT (current output means)
15a, 15b, 15c Current signal lines 17, 18 Power contact terminals 22, 23, 24 Signal processing means 25 Operation control means 251 Signal transmission system 252 Memory circuit part 253 Control circuit part 26 Setting input means 27 Output means 28 Power line 30 Power Meter 32 Time switch 34 Energy meter (for measuring midnight power)
54 Voltage transformer 55, 56, 57 Voltage signal line

Claims (4)

  At least two physical quantity detection means for continuously detecting a physical quantity that can be measured substantially instantaneously, and a signal for obtaining an instantaneous value by periodically sampling output signals from the respective physical quantity detection means at predetermined time intervals. A processing means, an arithmetic control means for performing a comparison operation in synchronism with at least the instantaneous value obtained in time series or the change amount of the instantaneous value among the detection means, and the comparison calculation result has a predetermined condition. A measurement output device including output means for performing predetermined output processing in some cases.   The measurement output device according to claim 1, wherein at least two physical quantities detected by the physical quantity detection unit are of the same type.   The measurement output device according to claim 2, wherein the physical quantity is a current. At least two current detection means installed on a power line constituting the power line and continuously detecting a current flowing through the power line;
Voltage detecting means for detecting a line voltage applied to the power line;
An electric energy metering mechanism for calculating electric energy using the electrical signals from the detection means as appropriate;
Signal processing means for obtaining an instantaneous value by periodically sampling the electrical signals from the current detection means at predetermined time intervals;
An arithmetic control means for performing a comparison operation by synchronizing the instantaneous value obtained in time series or the change amount of the instantaneous value at least between the current detection means,
An electric energy metering system comprising: output means for performing a predetermined output when the comparison calculation result has a predetermined condition together with or separately from the electric energy metering result.

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