JPH0963706A - Outlet with current monitor - Google Patents

Abstract

(57) Abstract: It is possible to realize current display with a simple circuit and easily adjust the current display value. A current display unit (13) is provided on the secondary side of a current transformer (22). The current display unit 13 includes a plurality of liquid crystal displays LCD1 and LC.
D2 and LCD3, and resistors R1, R2, and R3 are connected in parallel to them. Further, either one of the winding numbers n1, n2, n3 or the resistors R1, R2, R3 on the secondary side of the current transformer 22 is changed, and the current display unit 13 causes the plurality of liquid crystal displays LCD1, LCD2, LCD3 to change. Adjust the operating voltage.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an outlet with a current monitor.

[0002]

2. Description of the Related Art Generally, an outlet is provided with a pair of slits into which plugs are inserted on the surface of a housing, and a housing for contacting the tip of the plug is provided in the housing inside these slits. A branch line from the main electric wire is connected to these receivers and supplies electric power to the load.

By the way, the allowable current is usually fixed in the outlet. When an electric appliance which consumes a relatively large amount of current, such as an electric kotatsu or an electric heater, is connected to a single outlet in winter or the like, the outlet is overloaded and overheated, which may cause a fire. Therefore, it is important to understand the magnitude of the current flowing from the outlet to the load from the viewpoint of preventing accidents.

As a means for this, there is a method of calculating from the rated power of the load to be connected, but it takes time and effort. Further, there is a device such as the actual development 61-36973 which has a function of displaying a light emission when energized, but it cannot be judged depending on the magnitude of the current, and it is difficult to prevent an accident.

On the other hand, Japanese Patent Laid-Open No. 4-6776 discloses a current display through a drive circuit based on an output signal of a comparison circuit for comparing a voltage corresponding to a detected current with a reference voltage. .

[0006]

SUMMARY OF THE INVENTION
The device disclosed in 4-6776 requires a drive circuit, a comparison circuit, and a voltage dividing resistor for generating each reference voltage, and the circuit configuration is complicated. Further, when it is desired to change or adjust the current display value, it is not easy to change the voltage dividing resistance of the voltage dividing resistor or change to a drive circuit or a comparison circuit corresponding to it. An object of the present invention is to provide an outlet with a current monitor that can realize current display with a simple circuit and can easily adjust the current display value.

[0007]

In order to achieve the above object, the present invention relates to a current monitor outlet having a display means for displaying a current supplied to a load, and a current transformer for detecting a current flowing to the load. Since the resistance provided on the secondary side of the current transformer and the liquid crystal display connected in parallel to the resistance are provided, at least one of the number of windings and the resistance value on the secondary side of the current transformer. The current display value can be adjusted simply by changing.

Further, in an outlet with a current monitor having a display means for displaying the current supplied to the load, a current transformer for detecting the current flowing to the load, and an LED provided on the secondary side of the current transformer, L connected in parallel to the LED
Since the ED protection means is provided, the current display value can be adjusted only by changing the number of turns on the secondary side of the current transformer.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic view of an outlet with a current monitor showing an embodiment of the present invention. In the figure, an outlet 11 with a current monitor is an outlet for supplying electric power.
12 and a current display unit 13 that displays the current (current used) flowing to the load. In this embodiment, the current display section
Reference numeral 13 is composed of an LCD 1, an LCD 2 and an LCD 3, which will be described later, and each LCD operates when a current of, for example, 1A, 5A or 10A flows. Reference numeral 14 denotes an alarm unit, which is composed of an LED that lights up when the current level that can be displayed by the current display unit 13 is exceeded and the allowable current of the outlet 12 is exceeded, for example, 15A.

FIG. 2 is a circuit diagram of the outlet with current monitor shown in FIG. In the figure, 21 is an AC power supply, which is connected to the outlet 12 via the primary side of the current transformer 22. The number of turns on the secondary side of the current transformer changes depending on the current display level. When displaying on the current indicator 13, LCD1 ・ L
Resistors R1 to R3 are connected in parallel with each of CD2 and LCD3, and LCD1 and LCD2 are connected by an AC voltage across the resistors.
-The LCD3 segment is lit.

In the alarm unit 14, an LED is connected to the secondary side of the current transformer 22, and a diode D for flowing a reverse current is connected in parallel with the LED. The primary winding number N, the secondary winding numbers n1 to n4, and the secondary resistors R1 to R3 of the current transformer 22 are values necessary for turning on the respective LCD1 to LCD3 and LEDs, and more than that. The current is set so that the conversion efficiency does not drop and overvoltage or overcurrent is not applied.

In such a structure, when a current flows from the outlet 12, the current flows through the current transformer 22 to the secondary side of the current transformer 22. When the LCD1 to LCD3 of the current display unit 13 are turned on, the resistors R1 to R3 convert the voltage to a voltage, and this voltage is turned on when a desired current is applied. The number of turns and the resistance value of the primary side and the secondary side of the current transformer are higher than the primary side current to be turned on and the primary side current to be turned on.
At least one of D1 to LCD3 is set so that an overvoltage is not applied.

When the LED of the alarm unit 14 is turned on, it is turned on by the current on the secondary side of the current transformer 22. Furthermore, L
As with the CD, the number of turns on the primary side and the secondary side of the current transformer 22 is such that the conversion efficiency is reduced and the overcurrent does not occur in the LED when the primary side current to be turned on and the primary side current to be turned on are higher than the current.
I am trying to set it.

As described above, according to this embodiment, the current transformer 22 for detecting the current flowing to the load, the resistors R1 to R3, and L
The current display unit 13 composed of CD1 to LCD3 and LE
The current display can be realized with a simple configuration of the alarm unit 14 made of D. Further, when the allowable current is exceeded, it can be recognized at a glance by the alarm unit 14, so that the connected load can be immediately reduced and the occurrence of an accident due to overload can be prevented.

Further, when it is desired to adjust the current display value, the number of turns n1 to n3 and n4 on the secondary side of the current transformer 22 and the resistor R are set.
It suffices to change at least one of 1 to R3, which can be performed extremely easily compared with the conventional method.

In this embodiment, the current indicator 13
Although the LCD and the LED are used as the alarm unit 14, the combination can be appropriately changed. In addition, it can be applied not only to installed outlets but also to outlet taps that are connected to existing outlets.

[0017]

As described above, according to the present invention, in the outlet with a current monitor having the display means for displaying the current supplied to the load, the current transformer for detecting the current flowing to the load and the current transformer. Since the resistor provided on the secondary side and the liquid crystal display connected in parallel to the resistor are provided, current display can be realized with a simple circuit and the current display value can be easily adjusted.

Further, in an outlet with a current monitor having display means for displaying the current supplied to the load, a current transformer for detecting the current flowing to the load, and an LED provided on the secondary side of the current transformer. L connected in parallel to the LED
Since the ED protection means is provided, the current display can be realized with a simple circuit and the current display value can be easily adjusted.

[Brief description of drawings]

FIG. 1 is a schematic view of an outlet with a current monitor showing an embodiment of the present invention.

FIG. 2 is a circuit diagram of an outlet with a current monitor showing an embodiment of the present invention.

[Explanation of symbols]

 13 ... current display, 14 ... alarm

Claims (4)

[Claims] 1. An outlet with a current monitor having a display means for displaying an electric current supplied to a load, a current transformer for detecting a current flowing to the load, and a resistor provided on a secondary side of the current transformer. An outlet with a current monitor, comprising: a liquid crystal display connected in parallel to a resistor. 2. An outlet with a current monitor having a display means for displaying a current supplied to a load, a current transformer for detecting a current flowing to the load, and an LED provided on a secondary side of the current transformer. LEDs connected in parallel to the LEDs
An outlet with a current monitor, which is provided with a protection means. 3. An outlet with a current monitor having a display means for displaying a current supplied to a load, and a current transformer for detecting a current flowing to the load, and a plurality of resistors provided on a secondary side of the current transformer. And a plurality of liquid crystal displays connected in parallel to these resistors, by changing at least one of the number of turns on the secondary side of the current transformer or the resistance value of the plurality of resistors, by a plurality of resistors An outlet with a current monitor, characterized in that the liquid crystal display is operated by each converted voltage. 4. An outlet with a current monitor having a display means for displaying a current supplied to a load, and a current transformer for detecting a current flowing to the load, and a plurality of LEDs provided on a secondary side of the current transformer. And a plurality of LED protection means connected in parallel to these LEDs, the number of turns on the secondary side of the current transformer is changed, and each of the resulting currents causes the LE to change.
An outlet with a current monitor, characterized in that D is operated.