JPH0210466Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Application of the Invention) The present invention is an electronic electric energy system that displays operation by flashing light emitted from a light emitting element and displays the magnitude of a measured quantity by the flashing cycle. This is related to the improvement of the meter.

(Background of the invention) As shown in FIG. 5, a conventional general electronic watt-hour meter detects a voltage V proportional to the load voltage and a load current using a power detection circuit 1 consisting of a time-sharing multiplier and the like. A current signal (or voltage signal) corresponding to the power is obtained by multiplying by a current I proportional to the current I, and this current signal is converted into a frequency by a frequency conversion circuit 2,
This frequency is reduced by a certain percentage by a frequency dividing circuit 3, and the divided output is integrated by a counter 4 and displayed as an amount of electric power. The electronic electricity meter is
Since it is a stationary meter that does not have a rotating part like the disc of an inductive watt-hour meter, it is difficult to check the operating status, especially at light loads. An operation display device 5 built into the electronic watt-hour meter is driven by a relatively high-frequency pulse _P3 outputted from the frequency dividing stage. The operation display device 5 is composed of a transistor Tr, a light emitting diode 6, and resistors R _{1 and R 2 as} shown in FIG. By being applied to the base, the transistor Tr
is intermittently turned on and the supply voltage +V _DD is connected to the resistor R ₂
The voltage is applied to the light emitting diode 6 through the . As a result, the light emitting diode 6 blinks and emits light at a blinking cycle that corresponds to the magnitude of power consumption of the load. Note that the light emitting diode 6 is arranged at the upper right corner of the front face of the electronic watt-hour meter.

By the way, since watt-hour meters are often installed outdoors, the operation display device 5 has attracted much more attention than inductive watt-hour meters because it flashes and emits light even at night. As a result, third parties are made aware of and informed of the consumer's electricity usage, which is undesirable in terms of protecting the consumer's privacy or crime prevention. Furthermore, flashing lights at night give viewers a strange feeling, such as ``creepy'' or ``the meter is on fire.''

On the other hand, in conventional electronic watt-hour meters, high-frequency pulses can be taken out from the appropriate frequency division stage of the frequency conversion circuit 2 or frequency division circuit 3 for testing purposes, but for this purpose, the terminal A part of the board was changed and a new terminal was added to take out the pulse output.

(Purpose of the invention) The purpose of the invention is to solve the above-mentioned problems, to prevent the operation display from attracting the attention of third parties, and to provide a test pulse with a special structure. An object of the present invention is to provide an electronic watthour meter that can be taken out without modification.

(Characteristics of the invention) In order to achieve the above object, the present invention incorporates a light emitting element in a terminal block whose front side is covered with a terminal cover and whose bottom side is exposed, and transmits light from the light emitting element to the terminal block. A front side light guide hole and a bottom side light guide hole are formed in the terminal block, and at least one of the front side light guide hole and the bottom side light guide hole is used to receive light from the outside. The device is shaped so that the device can be inserted in a detachable manner, and the front light guide hole and the bottom light guide hole of the terminal block are shared for operation confirmation and for extracting pulses for testing. .

(Embodiment of the invention) Figures 1 to 4 show an embodiment of the invention. Portions similar to those in FIG. 5 are designated by the same reference numerals.

As shown in FIG. 2, the electronic watt-hour meter 10 is covered on the outside by a metal base 11 and a glass cover 12, and a terminal board 1 is provided at the bottom of the metal base 11 and a glass cover 12.
It has 3. FIG. 3 shows a state in which the terminal cover 14 is removed from the terminal board 13. The terminal board 13 includes a terminal block 15 made of synthetic resin, a terminal fitting 16, a terminal screw 17, and a terminal cover 14. The lower surface of the terminal block 15 is exposed so that the electric wire connected to the terminal fitting 16 can pass therethrough.

Inside the terminal block 15, as shown in FIG. 1, a light emitting diode 6 of the operation display device 5 is housed. Connect the light from light emitting diode 6 to terminal block 1.
A front side light guide hole 18 and a bottom side light guide hole 19 are formed in the terminal block 15, which lead out to the front side and the bottom side of the terminal block 5, respectively. The front side light guide hole 18 and the bottom side light guide hole 19 have a length and a diameter necessary for inserting a light receiver (described later) for extracting test pulses to the outside, Each of the step portions 20 and 21 is provided to determine the position. 22 is a printed board, and 21 is a ring-shaped stopper.

First, the operation display of the electronic watt-hour meter 10 will be explained. Since the terminal cover 14 is removed from the terminal board 13 during the installation work of the electronic watt-hour meter 10, the worker can see the light emitted from the light emitting diode 6 through the front light guide hole 18. Therefore, the operation can be easily confirmed from the front. During normal use when the terminal cover 14 is attached, the light from the front light guide hole 18 is cut off by the terminal cover 14, and the light from the light emitting diode 6 exits only through the bottom light guide hole 19. It is possible to prevent an unspecified number of third parties from watching the operation display. In addition, the parties shall
You can check the operation at any time by looking at it from below.

Next, extraction of pulses for testing will be explained. In this case, a light receiver for extracting pulses is inserted into the front light guide hole 18 or the bottom guide hole 19. FIG. 4 shows a state in which the light receiver 24 is inserted into the lower surface side lead-out hole 19. The light receiver 24 is inserted until it hits the stepped portion 21. The light receiver 24 is held in that position by frictional contact between the lower surface side lead-out hole 19 and the light receiver 24 or by a holding mechanism (not shown). The light receiver 24 has a light receiving element 25 at its tip. The light receiving element 25 receives the blinking light from the light emitting diode 6 and converts it into the original pulse _P3 . Therefore,
Pulse P ₃ can be taken out without requiring a terminal for taking out pulses for testing.

(Modification) In the illustrated embodiment, the light receiver 24 is inserted into both the front light guiding hole 18 and the lower surface guiding hole 19, but the light receiver 24 is inserted into only one of them. It may also be a hole.

(Effects of the invention) As explained above, according to the invention, a light emitting element is built into the terminal block whose front side is covered with a terminal cover and whose bottom side is exposed, and the light from the light emitting element is transmitted to the terminal block. A front side light guide hole and a bottom side light guide hole are formed in the terminal block, and at least one of the front side light guide hole and the bottom side light guide hole is used to receive light from the outside. The device is shaped so that it can be inserted removably, and the front light guide hole and bottom light guide hole are used both for operation confirmation and for extracting pulses for testing. It is possible to avoid attracting the attention of third parties, and furthermore, the pulse for testing can be taken out without any particular structural change.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing one embodiment of the present invention;
The figure is a front view showing the entire electronic watt-hour meter, Figure 3 is a front view showing the inside of the terminal board, and Figure 4 is a cross-sectional view showing the light receiver inserted into the outlet hole on the bottom side. , FIG. 5 is a block diagram showing an electronic watt-hour meter equipped with a conventional operation display device. 1... Power detection circuit, 2... Frequency conversion circuit,
3... Frequency division circuit, 4... Counter, 5... Operation display device, 6... Light emitting diode, 13... Terminal board, 14... Terminal cover, 15... Terminal block, 18... Front side light guide Hole, 19... Bottom side light guide hole, 20, 21... Step part, 24... Light receiver, 25
……Light receiving element.

Claims (1)

[Scope of utility model registration request] In an electronic watt-hour meter, the front side is covered by a terminal cover, and is equipped with an operation display device that displays operation by flashing light from a light-emitting element and also displays the magnitude of the measured quantity by the flashing cycle. The light emitting element is built into the terminal block whose lower side is exposed, and a front side light guide hole and a lower side light guide hole are configured to guide the light from the light emitting element to the front side and the bottom side of the terminal block, respectively. An electronic watt-hour meter characterized in that a terminal block is formed with at least one of the front light guiding hole and the bottom light guiding hole having a shape into which a light receiver is removably inserted from the outside.