JPH086298Y2 - Electronic watt-hour meter with status display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Use of the Invention) The present invention relates to an improvement of an electronic watt-hour meter equipped with a display for displaying a measured value.

(Background of the Invention) In recent years, an electronic watt-hour meter has been put into practical use in place of the conventional inductive watt-hour meter and has become widespread.

The electronic watt-hour meter rotates an aluminum disk at a speed proportional to the electric power by the eddy currents generated by the voltage coil and the current coil, and transmits the rotation of the disk by a gear, which is integrated with the gear. Unlike the inductive watt-hour meter that displays the integrated value of rotation on the display window with the rotary type numeric display, there is no moving part for measurement such as the aluminum disk in the case of the inductive watt-hour meter, and For the measurement, the measurement unit multiplies the outputs of the instrument transformer and current transformer by the multiplier,
It is converted electronically into a voltage, and a pulse with a frequency proportional to the result is created by a voltage-frequency converter and input to a microcomputer.Since it is all done electronically, it is not the measured value from outside the electronic watt-hour meter. It was not possible to know the operating state of, that is, the load state.

Therefore, when it is necessary to display the state, a separate display function indicating the required state, for example, a blinking display element is individually added.

Further, there has been conventionally proposed a method of displaying a load usage state by a bar with respect to a rated power.

However, the blinking display showing the operating state and the bar display showing the load state are not always sufficient to know the state of the electronic watt hour meter.

(Purpose of the Invention) An object of the present invention is to provide an electronic watt-hour meter with a status display that can inform many states of the electronic watt-hour meter in an easy-to-understand manner.

(Characteristics of the Invention) In order to achieve the above object, the present invention is a state in which a load state, an operating state, a no-load state, and a reverse current state of an electronic watt-hour meter are calculated from pulses of a frequency proportional to load power. The calculation means is provided, and the display unit integrally includes a measurement value display section for displaying the measurement value of the electric energy and a status display section for displaying the status calculated by the status calculation means. It is characterized in that a bar display area for displaying a load state and a reverse current state in a bar display and a character display area for displaying an operating state, a no-load state and a reverse current state in a character display are provided.

(Embodiment of the Invention) FIG. 1 is a front view of a display in an electronic watt-hour meter with a status display, which is an embodiment of the present invention.

As shown in FIG. 1, an indicator 1 according to an embodiment of the present invention includes a measurement value display section 2 and a measurement condition display section 3,
The status display unit 4 is replaced with the weighing value display unit 2 and the measurement condition display unit 3.
And a liquid crystal display element are most suitable.

FIG. 2 is a block diagram of an electronic watt-hour meter 5 with a status display, which is an embodiment of the present invention.

In the electronic watt-hour meter 5, the voltage V / current I (input voltage / input current of the measuring unit 7) is set by the rating setting switch 6.
Of the external instrument transformer and the current transformer (not shown) to be used by the setting conversion ratio setting switch 8, and the setting conversion ratio is set according to the standard of the external transformer and the current transformer (not shown). While setting the rate (1,10,100, etc.),
The pulse weight multiplying factor setting switch 10 is used to set the multiplying factor of the output pulse weight, and these setting conditions are input to the microcomputer unit 11, respectively.

In addition, by the pulse output selection switch 12, the transmitter 13
Select the relay contact output or photo coupler output pulse output method.

The transmitter 13 is controlled by the microcomputer unit 11, and the rating setting switch 6, the setting shift ratio setting switch 8,
A pulse having a pulse width that meets the conditions set by the multiplication factor change switch 9 and the pulse weight multiplication setting switch 10 is output by the output method selected by the pulse output selection switch 12.

Furthermore, the kWh, kvarh, kVAh changeover switch 14 is used to set the measurement types of active energy, reactive energy, and apparent energy.

Then, the display unit 1 displays the measured value on the measured value display unit 2, the multiplication factor display on the measurement condition display unit 3, and the kWh, kvarh, kV.
In addition to the Ah display, the load display, operation display, no load display, reverse current display, and transmission pulse display on the status display unit 4 are performed.

The state displayed on the state display unit 4 is calculated by the microcomputer unit 11 from a pulse having a frequency proportional to the load power, which is input from the measuring unit 7 to the microcomputer unit 11 (details will be described later). The state calculation function of the microcomputer section 11 is shown as the state calculation means 15 in FIG. The state calculated by the state calculation means 15 is sent to the state display section 4 and displayed.

The measurement conditions set by the setting switch are as follows: Multiplier display 16 on the upper left part of the display 1 and kWh, kvarh, kVAh on the upper right part.
A display 17 is provided.

Next, regarding the status display which is the feature of the present invention, in the example shown in FIG. 1, as a kind of integrated status display, load status display 18: bar display operation display 19: “LOAD” display no load display 20: "NO LOAD" display Transmitted pulse display 21: Lighting display Reverse current display 22: Bar display and "REVERSE" display Five status display functions are provided.

FIG. 3 shows an electronic watt-hour meter 5 with status display (effective).
The display when operating as an electricity meter is shown. In this case, the upper right display is "kWh" and the load status display 18
At the same time, the “LOAD” display of the operation display 19 is performed, and thus the normal measurement of the active electric energy is displayed.

FIG. 4 shows a case where the no-load state is displayed.
With no load, that is, when only voltage is applied,
No load display 20 only displays "NO LOAD".

FIG. 5 shows an operation flow chart of the microcomputer unit 11 (state calculating means 15) of the electronic watt-hour meter 5 with a status display which performs the load status display 18, the operation display 19 and the no-load display 20.

In step 1, the microcomputer unit 11 detects a pulse having a frequency proportional to the power value, and in step 2, when the frequency is below a certain value, it is determined that there is no load, and in step 3, the load status display 18 The operation display 19 is turned off, and the no-load display 20 is turned on in step 4. Step 2
If the frequency is equal to or more than a specified value, it is determined that the load condition is present, and the load condition display 18 proportional to the frequency detected in step 5 is displayed in a bar and the operation display 19 is performed in step 6.
Lights up.

Further, as shown in the operation flow chart of the microcomputer section 11 (state calculating means 15) in FIG.
The pulse having a frequency proportional to the electric power value output by the measuring unit 7 is counted by 12 by the pulse counter built in the microcomputer unit 11, and the set rating, the set transformation ratio, and the pulse weighting factor read in step 13 are read. Calculate the frequency division value in step 14 from the above, and each time the pulse counted by the pulse counter in step 15 matches the frequency division value, in step 16 the transmitter
At the same time that the transmission pulse is output to 13 and the transmission pulse display 21 is lit for a certain time in step 17, that is, in FIG. 3, the transmission pulse display 21 emits light in synchronization with the output of the transmission pulse and View the output. In step 18, the pulse counter clears to zero each time the counted pulse matches the frequency division value.

FIG. 7 shows a display when the electronic watt-hour meter with status display 5 is operating as a reactive watt-hour meter. In this case, the upper right display changes to "kvarh".

Further, FIG. 8 shows a display when the reverse current is measured. The reverse current is measured by multiplying the outputs of the instrument transformer 23 and the current transformer 24 in the measuring unit 7 whose block diagram is shown in FIG. 9 and outputting a voltage proportional to the resulting power value. The polarity of the output voltage of the transformer 25 is compared by the voltage comparator 26, and in the case of a reverse current, the phase rotation direction of the current of the current transformer 24 is opposite to that in the case of a positive current, so that the output of the multiplier 25 becomes negative. Is detected by the voltage comparator 26 and a reverse current signal is sent to the microcomputer unit 11 to display the reverse current.
Do 22 The voltage-frequency converter 27 sends out a pulse having a frequency proportional to the power value as an input pulse of the microcomputer unit 11.

In this way, according to the electronic watt-hour meter with status display 5,
It is possible to display various load states and operating states together with the weighing value display.

(Effect of the Invention) As described above, according to the present invention, the state calculation for calculating the load state, the operating state, the no-load state, and the reverse current state of the electronic watt-hour meter from the pulse of the frequency proportional to the load power Means is provided, and the display unit is integrally formed with a weighing value display section for displaying the weighing value of the electric energy and a status display section for displaying the status calculated by the status calculating means, and the status display section is provided with a load. Since the bar display area for displaying the current status and the reverse current status in the bar display and the character display area for displaying the operating status, the no-load status and the reverse current status in the character display are provided, many of the electronic watt hour meters are provided. You can inform the state in an easy-to-understand manner.

[Brief description of drawings]

FIG. 1 is a front view of an indicator in an electronic watt-hour meter with a status display, which is an embodiment of the present invention, FIG. 2 is a block diagram of the same electronic watt-hour meter with a status display, and FIG. The front view of the display that displays the load status and the transmission pulse of the electric energy, Fig. 4 is the front view of the display that displays the no load, and Fig. 5 shows the operation of the load status display, the operation display and the no load display. FIG. 6 is a flow chart showing the operation of transmitting pulse display, FIG. 7 is a front view of a display for displaying the load state of reactive energy, and FIG. 8 is a front of the display for displaying reverse current. FIG. 9 and FIG. 9 are block diagrams of the measuring unit. 1 ... Display unit, 2 ... Weighing value display unit, 3 ... Measurement condition display unit, 4 ... Status display unit, 5 ... Electronic watt hour meter with status display, 6 ... Rating setting switch, 7 ... … Measuring section, 8 ……
Setting shift ratio setting switch, 9 ... Multiplier switch, 10
...... Pulse weight multiplication setting switch, 11 ...... Microcomputer section, 12 ...... Pulse output selection switch, 13 …… Transmission device, 14 …… kWh, kvarh, kVAh changeover switch, 15 …… State calculation means, 16 …… Multiplier display, 17 …… kWh, kvarh, kVAh display, 18 …… Load status display, 19 …… Operation display, 20 …… No load display, 21 …… Transmission pulse display, 22 …… Reverse current display, 23
…… Instrument transformers, 24 …… Current transformers, 25 …… Multipliers, 26 ……
… Voltage comparator, 27 …… Voltage-frequency converter.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsuji Naka 3-15 Toyotama Naka, Nerima-ku, Tokyo Miyamoto Mansion B105 (72) Inventor Yukihiro Hoshino 1007 Shimonoda Shiraoka-cho, Minami Saitama-gun, Saitama Prefecture (56) References 61-111469 (JP, A)

Claims (1)

[Scope of utility model registration request] 1. An electronic watt-hour meter that generates a pulse having a frequency proportional to load power, counts the pulses, and displays the watt-hour as a power amount on a display device. A state calculation means for calculating the state, the no-load state, and the reverse current state from the pulse is provided, and the display unit displays the measurement value display section for displaying the measurement value of the electric energy and the state calculated by the state calculation means. A status display section for displaying is integrally formed, and a bar display area for displaying the load status and the reverse current status in a bar display and the operating status, the no-load status and the reverse current status are displayed on the status display section. An electronic watt-hour meter with a status display, which is provided with a character display area for displaying by a display.