JPS6154474A - Testing device for watthour meter - Google Patents

Abstract

PURPOSE:To display the instrumental error of each watthour meter to be tested in percentage with simple circuit constitution by using pulses obtained by the induction rotary disk of a reference watthour meter as a reference signal, and subtracting and adding them unitl the induction rotary disk of the watthour meter to be tested rotate by 360 deg.. CONSTITUTION:The testing device is provided with a rotation detector 31 which generates a pulse at every specific angle of rotation according to the rotation of the induction rotary disk of the reference watthour meter 1, a rotational period detector 32 which detects the period where the induction rotary disk 7 turns by 360 deg., and a counter part 14 which counts pulses corresponding to output pulses of the rotation detector 31 throughout the detection period detected by the rotational period detector 32. Further, a display part 17 displays the counted value, a detection control part which allows the counter part 14 to count reversely when its counted value attains to 0 and also inverts the polarity of the display part 17, and a setting part 3 which sets a specific value including the instrumental error of the reference watthour meter 1 and supplies this value to the counter part 14. Consequently, when the object watthour meter 6 is tested, the induction rotary disk needs not be set at a set zero position and the instrumental error needs not be calculated either.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for conducting a test by comparing the induction rotary plate of a standard watt-hour meter with the induction rotary plate of a watt-hour meter under test.

[Conventional technology]

Conventionally, it is the 5th method to test the instrumental error of electric energy meters.
The structure shown in the figure is known. FIG. 5 is a schematic diagram of the watt-hour meter master meter method test device.

In FIG. 6, when the switch 20 is turned on, the current flows through the voltage and current power factor adjusting device [19] to the voltage coils 4.
24n and current coils 25, 25a to 25n.

As a result, the induction rotary plates 2.7 to 7n are rotated.

Power meter 22. The current meter section is only for indicating power and current, and is connected via a transformer 21. To explain the test method, the zero position of the scale 26 provided on the induction rotating plate 2 of the reference watt-hour meter 1 and the induction rotating plate γ to 7n of the tested watt-hour meter 6 to 6n is set to the set position 27. do.

After completing the setting of each induction rotary plate 2.7 to 7n,
Turn on the switch 20 and set the reference power meter 1. The induction rotary plates 2.7 to 7n of the power meters to be tested 6 to 6n are simultaneously rotated. The induction rotary plate 2 of the reference watt-hour meter 1 rotates a predetermined number (integer), and 2B is at the set position 27 at the zero position of the induction rotary plate 2.
Turn off the switch 20 to turn off the power and stop all the electricity meters at the same time. At this time, how much the zero position 28 of the tested watt-hour meter 6 to 6n deviates from the set position 27 set at the time of rotation start is read on the scale 26, and this value is calculated in advance for the reference watt-hour meter 1. By adding the instrumental errors, the instrumental errors of the watt-hour meters to be tested 6 to 6n are calculated. This is a device used when testing a large number of watt-hour meters at the same time in manufacturing plants and the like.

[Problem that the invention seeks to solve]

However, in such conventional test equipment, humans were responsible for setting the zero position of the induction rotary plate to the set position and calculating the instrumental error of the watt-hour meter under test. If an error occurs when setting the position to the set position, or if the number of dynamometers to be tested increases, the time required to set the zero position of the induction rotary plate to the set position and the total amount of electricity consumed each time a test is performed. There were problems such as the time it took to calculate the instrument error of the watt-hour meter under test by adding the instrument error of the reference watt-hour needle to the scale of the watt-hour meter under test after rotating the meter a predetermined number of times (an integer number). .

[Failure to solve the problem]

The present invention includes a rotation detector 31 that generates a pulse at each predetermined rotation angle in response to 20 rotations of the induction rotary plate of the reference watt-hour meter 1, and a period during which the induction rotary plate 7 of the watt-hour meter 6 under test rotates 360°. During the detection period detected by the rotation period detector 32 of the rotation period detector 32, a counter unit 14 counts pulses corresponding to the output pulses of the rotation detector 31, and a counter unit 14 that counts pulses corresponding to the output pulses of the rotation detector 31, Display section 1 to display
7, a detection control unit that performs counting in the opposite direction and inverts the polarity of the display unit 17 when the value of the counter unit 14 becomes O, and a predetermined value including the instrumental error of the reference watt-hour meter 1. Setting unit 1 sets this value and gives this value to the counter unit 14.
3 eliminates the need for humans to set the induction rotating body to a set zero position or calculate instrumental errors, which were performed by humans when testing the watt-hour meter 6 to be tested.

[Effect]

According to the present invention, the induction rotary plate 2 of the reference power meter 1 is
The reference number of pulses generated when rotating 60 degrees, and the number of pulses corresponding to the rotation angle of the induction rotary plate 20 of the reference watt-hour meter 1 while the induction rotary plate 1 of the watt-hour meter 6 under test rotates 360 degrees. The instrument error of the watt-hour meter 6 to be tested is determined by comparing the values in the counter section.

〔Example〕

FIG. 1 is a schematic configuration diagram of a test apparatus according to an embodiment of the present invention, and FIG. 2 is a partially enlarged view of an induction rotary plate of a reference watt-hour meter.

In FIG. 1, a predetermined number of induction rotary plates 1B of a reference watt-hour meter 1 are provided at equal intervals as shown in FIG. This slit 18 is detected by a detector 3 such as a rotation sensor or an optical fiber of a rotation detector 31, and a pulse is generated at each predetermined rotation angle according to the rotation of the induction rotary plate 2 via the detection unit 4. is multiplied by a predetermined number of pulses by a multiplier circuit 5. The instrumental error when the reference watt-hour meter 1 rotates 3600 revolutions is set in advance in the counter section 14 by the setting section 13. This counter section 14
is a presettable up/down counter.

The rotation angle of the induction rotary plate 7 of the watt-hour meter 6 under test is detected by the creep hole 8 by a detector 9 such as a sensor of the rotation period detector 32 or an optical fiber, and a detector 10 . Then, a signal is supplied to the gate section 12 during the period from when the reset signal is given to the gate control section H by the gate control section H until the creep hole 8 is rotated 360' from the first detected creep hole 8 and detected again. The gate section 12 supplies the pulse from the rotation detector 31 to the counter section 14 while receiving the signal from the gate leg section 11 . The counter section 14 subtracts and counts the pulses of the rotation detector 31 from the value set by the setting section 13. The value at this counter section 14 is displayed on a display section 17 which can display the polarity. When the value of the counter section 14 becomes 0, the zero detection section 15 of the detection control section 29 detects 0 of the counter section 4, and the control circuit 16 inverts the polarity of the display section 17 and changes the counter section 14. Switch to addition count starting from 0.

To explain these specifically, when the induction rotary plate 2 of the reference watt-hour meter 1 rotates by 360', the rotation detector 31 detects the rotation detector 3. If the signal detected by the detection unit 4 is, for example, 250 pulses, this pulse is multiplied by the multiplier circuit 5 to 1000 Hals. This pulse is then supplied to the counter section 14 as a reference signal. Pulse f 1000 pulses is /. . . In other words, percentages can be expressed to one digit after the decimal point.

For example, if the instrumental error of the reference watt-hour meter 1 is +0.1%, the 360' rotation of the induction rotary plate 2 is 1000 pulses, so the setting section 13 sets the counter section K1001. (
If the instrumental error is -0.4%, set it to 996. ) With this setting, the display section 17 displays 00.1. This is because the display unit 17 is a 4f line display with 3 digits for the number and 1 digit for the polarity, so it appears to be 00.1.After the reset signal is given to the gate control unit U, the induction rotary plate 7 is From the time the creep hole 8 passes the detector 9, the counter part 1
4, the output pulses of the rotation detector 31 are subtracted and counted. Since the number of pulses is 100o pulses, the values of the counter section 14 are 1000, 999, 99 (3...
It decreases to 0. In line with this, the display section 17
The values are ↓00.9, 99.9, 99.8...
・・・・It becomes oOlo. When the creep hole 8 of the induction rotary plate 7 rotates 360' and passes through again, and the 360' rotation is detected, the counter section 14 stops counting. The numerical value displayed on the display section 1'7 at this time is the instrumental error of the watt-hour meter 6 to be tested. If the display unit 17 shows +01.0, the instrumental error of the watt-hour meter 6 to be tested is +1.0%. If the 360' rotation of the reference watt-hour meter 1 is faster than the 3600 rotation of the tested watt-hour meter 6, this is displayed.

Next, to explain the case where the 360° rotation of the watt-hour meter under test is slower than the 360° rotation of the reference watt-hour meter 1, even if the value of the counter section 14 becomes 0, the watt-hour meter under test 6
has not rotated 360°, the counter unit 14 attempts to continue subtraction. Then, the zero detection section 15 detects that the value of the counter section 14 has become O, and the control circuit 16 instantaneously switches the counter section 14 to addition counting and at the same time inverts the polarity of the display section 17.

As a result, if the display section 17 displays -00.8, the instrumental error of the watt-hour meter 6 to be tested is -0.8%.

FIG. 3 is a timing chart of the signals of each part in FIG. 1, and (A) is the output signal of the rotation detector 31.

(B) shows the output signal of the detection unit 10, and (C) shows the reset signal.

(D) is the output signal of the rotation period detector 32, and (E) is the input signal of the counter section 14.

As can be seen from the figure, the output signal of the rotation period detector 32 becomes high at the first output signal of the detection unit 10 after the reset signal is applied. Since two creep holes are provided in the induction rotary plate 7 of the watt-hour meter 6 under test, if the same creep hole is detected again after rotating 360 degrees from the detected signal, the rotation period detector is detected. The output signal of 32 is set to low. The output signal of the rotation detector 31 is given as an input signal to the counter section 14 only when the output signal of the rotation period detector 32 is high. FIG. A schematic configuration diagram is shown below.

In FIG. 4, when testing the watt-hour meters to be tested 6 to 6n together, each of the watt-hour meters to be tested 6 to 6n has a detection section IO to 10n, a gate control section 11 to lln, a gate section 12 to 12n, Counter sections 14 to 14n, zero detection section 15
-b is provided to form one test circuit 30-3On. Test circuits 30 to 3On are connected in parallel to the multiplier circuit 5 and the setting section 13, which are connected to the reference watt-hour meter 1 via the detection section 4, respectively. Thereby, the instrumental error of the reference watt-hour meter 1 set by the setting section 13 is given to each of the counter sections 14 to 14n. The pulses from the multiplier circuit 5 allow the test force strain gauges 6 to 6n to be individually tested.

〔Effect of the invention〕

The present invention uses a pulse obtained by a slit in the induction rotary plate of the reference watt-hour meter as a reference signal, and performs subtraction and addition while the induction rotary plate of the watt-hour meter under test rotates 3,600 revolutions. This provides the advantage of being able to display the instrumental error of the test watt-hour meter as a percentage. The instrument error of the watt-hour meter under test is displayed as a percentage, so it can be read directly, and it does not include the instrument error of the reference watt-hour meter, so one of the manufactured watt-hour meters can be used as the reference watt-hour meter. , no expensive standard equipment is required.

Furthermore, the accuracy of the test is improved by converting the rotational inversion of the induction rotary plate of the reference 1 dynamometer and the 360° rotation period of the induction rotary plate of the watt-hour meter under test into signals. Since the test is performed in accordance with the detection period of the watt-hour meter under test, there is no need to turn on the power supply or set the zero position, thereby reducing the time spent on the test.

In the present invention, the number of pulses detected from the reference watt-hour meter is set to 25.
0 pulse, the reference signal obtained by the multiplication circuit is 10
00 Hals, but the number of pulses can be set appropriately according to the power meter.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a test device that is an embodiment of the present invention;
Figure 2 is a partially enlarged view of the induction rotary plate of the reference watt-hour meter, Figure 3
The figure is a timing chart of each part signal in Figure 1, Figure 4 is a schematic configuration diagram when a plurality of test circuits are provided in a test device according to an embodiment of the present invention, and Figure 5 is a diagram of a conventional power meter master meter. A schematic configuration diagram of the legal testing device is shown. 1...Reference electricity meter, 2.7...Induction rotary plate, 6.
... Electric energy meter under test, 12~12n... Gate section, 1
3... Setting section, 14-14n... Counter section, 17
~17n... Display section, 29-29n... Detection control section, 30-30n... Test circuit, 31... Rotation detector, 32-32n... Rotation period detector. Figure 1 Slit Figure 3 Figure 4 Figure 5

Claims (1)

[Scope of Claims] 1) A rotation detector that generates a pulse at each predetermined rotation angle in accordance with the rotation of the induction rotary plate of the reference watt-hour meter; A rotation period detector for detecting a rotation period of the rotation period, and a counter section for counting pulses according to output pulses of the rotation detector during the detection period detected by the rotation period detector. Test equipment for electricity meters. 2) The test device according to claim 1, further comprising: a display unit that displays the value of the counter unit; and a display unit that detects that the value of the counter unit becomes 0 and performs counting in the opposite direction; What is claimed is: 1. A test device for a watt-hour meter, comprising: a detection control section for reversing the polarity of the section. 3) In the test device according to claim 1 or 2, a predetermined value including the instrumental error of the reference watt-hour meter is set in the setting section, and the counter section calculates the value from the value set by the setting section. A test device for a watt-hour meter, which is characterized by counting. 4) In the test device according to any one of claims 1 to 3, the rotation detector and the setting section include a rotation period detector, a counter section, a display section, and a detection control section. A power meter test device characterized by having multiple test circuits connected in parallel.