JPS6344773Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a current monitoring device, and more particularly to a current monitoring device for displaying the current amount of remaining usable current with respect to the contracted current.

[Prior art]

BACKGROUND ART In recent years, as lifestyles have improved, the use of electric and electronic devices in general households has rapidly progressed, and the amount of electricity used has also increased rapidly.
In this case, in recent years, there has been a tendency for appliances that consume a lot of power to be used frequently, such as microwave ovens, coolers, and dryers. Therefore, when using such electrical equipment that consumes a large amount of power, it is necessary to take into account the operating conditions of other electrical equipment and to ensure that the electrical current does not exceed the contracted current.

[Problem that the invention attempts to solve]

However, when there are many types of electrical equipment in use, it is extremely difficult to calculate the remaining usable current by considering the usage status of other electrical equipment. Even if the remaining usable current is determined, the usable current in this case will simply be the sum of the rated current values indicated for each electrical device. On the other hand, if the current consumption of the electrical equipment used varies greatly depending on the mode of use, such as an inverter-driven air conditioner, there may be a difference between the current consumption calculated by the above calculation and the actual current consumption. A large gap will occur. As a result, even though there is a sufficient margin between the contracted current and the current consumption, users are currently inconvenienced by restrictions on the simultaneous use of electrical devices.

On the other hand, it may be possible to use electrical equipment with sufficient margin by changing the contracted current to a higher class, but as the contracted current class increases, usage fees also increase accordingly. Therefore, it cannot be said to be an effective method.

Furthermore, if the amount of current used exceeds the contracted current due to simultaneous use of all electrical devices, for example, an electromagnetic breaker or fuse is activated to prevent the use of power exceeding the contracted current. When this electromagnetic breaker or fuse is activated, all power is cut off, so
When using a data processing device such as a personal computer or recording data using a video tape recorder, there is a problem in that irreversible troubles occur due to the interruption of the power supply.

[Means for solving problems]

In order to solve such problems, the present invention calculates the amount of current used at the present time, and calculates and displays the remaining amount of usable power from the relationship between this amount of current used and the contracted amount of current.

[Effect]

A current monitor device configured in this way displays the current amount of remaining usable current, so by taking this display into consideration when using electrical equipment additionally, the contracted current can be reduced. Even in such a case, it is possible to easily avoid a situation where an electromagnetic breaker or fuse is activated and cause a power outage, and effective current consumption can be achieved.

〔Example〕

FIG. 1 is a circuit diagram showing an embodiment of a current monitoring device according to the present invention. In the same figure, 1a, 1
b is a power bus line in a general household connected to the power company's service line, and these power bus lines 1a,
Various electric devices (not shown) are connected to the terminal side of 1b. A current detection transformer 2 as a current sensor is coupled to the power bus 1a, and the current flowing through the power buses 1a and 1b, that is, the current consumption current in the household is detected. Reference numeral 3 denotes a current detection unit, which inputs a signal corresponding to the current consumption output from the current detection transformer 2, performs rectification and correction processing, etc., and outputs a voltage signal corresponding to the current consumption value. .
4 is a contract current value switching unit for specifying a contract current value contracted with an electric power company;
An output signal having a level corresponding to the contract current value specified by the switch 5 is generated. Reference numeral 6 denotes a variable gain amplifier that amplifies and outputs the output signal of the current detection section 3, and its gain is varied according to the output level of the contract current value switching section 4. Reference numeral 7 denotes a display section, which is provided in a current value display section 8a, a remaining power amount display section 8b, a contract current display section 8c, and a section corresponding to the current value and remaining power consumption, as shown in FIG. indicator light 8d ₁ ~ 8
d ₁₀ , a level display control circuit 9 that selectively turns on the indicator lights 8d ₁ to 8d ₁₀ according to the output level of the variable gain amplifier 6, and a display board 8 having a contract current value switching section 4 according to the switching. It is constituted by a display control circuit 10 that changes the display of a current value display section 8a, a remaining power amount display section 8b, and a contract current display section 8c on the board 8.

In the current monitoring device constructed in this manner, when the contract current is, for example, 10A, the movable piece of the switch 5 is set to the fixed contact 5a. When the contract current is set in this manner, a signal indicating that the contract power has been set to 10A is supplied from the contract current value switching section 4 to the display control circuit 10 of the display section 7. When the display control circuit 10 receives this signal, the display control circuit 10 changes the display on the current value display section 8a on the display board 8 from 0 to 10.
Remaining available power display section 8b
In response to the current value display, nine levels from 900 to 100 are displayed, and 10A is displayed on the contract current display section 8c. Therefore, the display of each part in this case is the second
The result will be as shown in the figure.

Further, the contract current value switching section 4 controls the gain of the variable gain amplifier 6 according to the setting by the switch 5. In other words, the minimum contract current value is set to "1", and as the contract current value increases, it is controlled inversely proportionally, and when the contract current value is 20A, the amplification degree is "1/2".
will be set to . In this state, when various electric devices (not shown) connected to the power buses 1a and 1b are used, the current detection transformer 2
detects and outputs the current flowing through the power bus 1a. In this case, since the output signal output from the current detection transformer 2 is an alternating current, rectification, correction, etc. are performed in the current detection section 3, so that the output signal is adjusted to a level corresponding to the current value flowing through the power buses 1a and 1b. is supplied to the variable gain control amplifier 6 as a signal.

In this case, since the gain of the variable gain control amplifier 6 is set to "1" by the contract current switching section 4, the output signal of the current detection section 3 is assumed to be at the same level, and the level display control circuit 9 of the display section 7 is supplied to Then, the level display control circuit 9 compares the input signal with the reference value of the 10 level levels.
It is determined to which level this input signal corresponds. Then, by selecting the corresponding one of the indicator lights 8d ₁ to 8d ₁₀ provided on the display board 8 according to the result of this discrimination, the indicator lamp 8d ₈ shown in FIG. 2, for example, is turned on. The user confirms that the indicator light 8d ₈ is lit, and from the corresponding current value display "8" and the remaining usable power display "200", the current consumption current is 8A and the remaining usable power is available. Reads that the power is 200W and increases the use of electrical equipment within this 200W.

Next, if the contracted current is increased to, for example, 20A due to an increase in the current used during normal operation or the installation of new high-power equipment, the switch 5.
Rotate to select fixed terminal 5b for 20A setting. Then, the contract current value switching unit 4 determines that the contract current is
The display control circuit 10 of the display section 7 is informed that the current value is set to 20A. The display control circuit 10 changes the display of the current value display part 8a on the display board 8 shown in FIG. The display in the section 8b is changed to 9 levels from 1800 to 200, and the display in the contract current display section 8c is changed to 20A.
In addition, the contract current value switching unit 4 reduces the gain of the variable gain amplifier 6 to 1/2 in order to prevent the display scale from doubling due to the contract current being doubled from 10A to 20A. Perform scale adjustment as . Therefore, in this state, if the output value of the current detection section 3 is the same as that at the time of the previous 10A contract, the indicator light
The lighting positions of 8d ₁ to 8d ₁₀ are 1/1 compared to the previous case.
In the second row, the scale is also 1/2, so twice the range is displayed on the same scale. In this way, by making the scale on the display board 8 and the amplification factor of the variable gain amplifier 6 inversely proportional to the multiplication ratio of the contract current, it is possible to deal with various contract currents using the same scale.

[Effect of idea]

As explained above, since the current monitoring device according to the present invention displays the amount of available current remaining at the present time with respect to the contracted current in a simple configuration, the user should consider this display content. By using electrical equipment additionally, it is possible to prevent the power supply from being cut off due to activation of the electromagnetic breaker due to exceeding the contracted current, and to make effective use of the equipment by using it up to the contracted current value limit. It has various excellent effects.

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an embodiment of the current monitoring device according to the present invention, and FIG. 2 is a diagram showing an example of the display on the display section in FIG. 1. 1a, 1b...Power bus bar, 2...Current detection transformer (current detection sensor), 3...Current detection section,
4...Contract current value switching unit, 5...Switch, 6...
...Variable gain amplifier, 7... Display section, 8... Display board, 9... Level display control section, 10... Display control section.

Claims (1)

[Scope of utility model registration request] A current detection sensor that is attached to the power bus through which all the current used flows and detects the amount of current, and a current detection section that receives the output signal of this current detection sensor as input and outputs a signal at a level corresponding to the current flowing through the power bus. a contract current value setting section that sets a contract current value; and a variable gain that sets a gain that is inversely proportional to the set contract current value based on the output signal of the contract current value setting section and amplifies the output signal of the current detection section. A current monitor comprising: an amplifier; and a display section that displays the output signal level of the variable gain amplifier and also displays the current value of the level display section and the remaining available power according to the output of the contract current value switching section. Device.