JP2007147334A - Digital display current-monitoring unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a current-monitoring unit capable of being unitized so as to be additionally installed to an electrical installation apparatus, digitally displaying a value of a current flowing through a load, and outputting the current value to an external control apparatus. <P>SOLUTION: The current-monitoring unit is provide with a monitoring circuit part 6 made of an upper substrate 4 and a lower substrate 5 vertically connected at an interval from each other to a connecting means 24 inside the case body 1 comprising an upper case 2 and a lower case 3; a current transformer 20, of which a part is exposed from a transformer through hole 40 bored in the case body 1; an alarm buzzer 22 for issuing an alarm when the load current exceeds a preset value; a display part 10 for digitally displaying a load current value; a switch 13 for switching the preset value; a power supply connection terminal 21, exposed from a connection terminal through hole 41 bored in the case main body 1; and a support frame 45 for supporting a push button 33 for push operations of the display part 10 and the switch 13 inside the upper case 2, and fixing the lower substrate 5 to the lower case 3. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is a digital display current monitoring unit, more specifically, can be installed in addition to electrical equipment, digitally displaying the current value flowing through the load, and a digital display in which an alarm buzzer works when the current value exceeds a predetermined value It relates to a current monitoring unit.

  Conventionally, a clamp ammeter is generally known as a device for measuring a current flowing through a load (for example, Patent Document 1). This clamp ammeter opens a clamp with a clamp opening / closing lever, and sandwiches a current transformer housed in the clamp into a target electric circuit so that a detected current value is displayed on a current value display section. It was used as a measuring instrument.

Also, a digital measuring device (for example, Patent Document 2) has been proposed as a load current measuring device that measures load current. Since this measuring device is a conventional digital measuring device and can process transient current values because it is processed at high speed, it excludes transient current values and reliably measures actual load current values. It is something that can be done.
Utility Model Registration No. 3046007 JP 2004-245789 A

  The problem to be solved by the present invention is that the above-mentioned ammeter is not the one that the former clamp ammeter is added to the electrical equipment as a measuring instrument, but the latter ammeter measures the current accurately. However, it has not been proposed as a unitized apparatus for enabling the measurement apparatus to be installed by being added to electrical equipment.

  The present invention solves the above-mentioned problems, unitizes it so that it can be added to an electrical equipment device, displays the current value flowing through the load digitally, and outputs the measured current value to an external control device. It is an object to provide a current monitoring unit that can be used.

  In order to solve the above-mentioned problems, a digital display current monitoring unit according to the present invention is connected to a case main body composed of an upper case and a lower case with a connecting means within the case main body with a vertical interval. A monitoring circuit unit composed of a substrate and a lower substrate, a current transformer partially exposed to the outside from the transformer insertion hole formed in the case body, and an electric wire inserted through the current transformer outside the case body are energized. An alarm buzzer that issues an alarm when the load current exceeds a set value, a display unit mounted on the upper board for digital display of the load current value, and an upper board for switching and setting the set value Press the switch and the power supply connection terminal exposed from the connection terminal insertion hole drilled in the case body that supplies power to the monitoring circuit, and press the display and switch inside the upper case To support the push button that, said base substrate and a supporting frame to be fixed to the lower case.

  The case body is preferably provided with an output terminal for outputting a load current value to an external device so that the state of the load current can be grasped by the external control device.

  According to the invention of claim 1, the current monitoring device that can display the measured current digitally and can notify with an alarm sound when the current flows exceeding the current value set by the setting means is unitized, It is possible to provide a digital display current monitoring unit that can be easily incorporated into electrical equipment such as a switchboard or an outlet.

  According to the invention of claim 2, since the detected current value can be output from the output terminal as a measurement signal, the current flowing through the load can be monitored by an external control device such as a personal computer connected to the output terminal. Become.

  FIG. 1 shows an example of a digital display current monitoring unit according to the present invention. This digital display current monitoring unit (hereinafter referred to as a current monitoring unit) A monitors a current flowing through an electric wire, and the current value is a set value. The current monitoring device includes an upper case 2 and a lower case 3 so that the user can be notified of the excess and the current value can be grasped by an external control device such as a personal computer. The case body 1 accommodates a monitoring circuit unit 6 composed of an upper substrate 4 and a lower substrate 5.

  The upper substrate 4 that constitutes one of the monitoring circuit units 6 has a digital display LED 10 that is a display unit that digitally displays the current value to be monitored, and determines whether or not the current value to be monitored exceeds a set value. The control unit 12 that activates the alarm buzzer 22, the switch 13 that switches and sets the set value, and the output terminal 14 that outputs the detected current value to the outside are mainly arranged and monitored. A current transformer 20 for detecting a current flowing in the electric wire and a power supply connection terminal 21 for supplying power to the monitoring circuit unit 6 are arranged on the lower surface of the lower substrate 5 constituting the other side of the circuit unit 6. An alarm buzzer (composed of a piezoelectric buzzer) 22 is arranged to notify that the current value detected by the current transformer 20 has exceeded a predetermined value.

  The upper substrate 4 and the lower substrate 5 are connected to each other by a connecting means 24 with an interval in the vertical direction. This connecting means is composed of two support columns 25 and a connection printed circuit board 26, and is formed on the connection printed circuit board 26 so that the upper substrate 4 and the lower substrate 5 are electrically integrated into one substrate. The monitoring circuit unit 6 is configured by being electrically connected by the printed wiring 27 (see FIGS. 2A and 2B).

  As shown in FIG. 3, the upper case 2 that constitutes one of the case main bodies 1 that accommodates the monitoring circuit unit 6 can be viewed through the transparent cover 30 through the three-digit digital display LED 10 that is a display unit. In this way, a rectangular opening 31 is formed, and a slit 32 for emitting sound of the piezoelectric buzzer 22 which is an alarm buzzer arranged inside the opening 31 and an opening for projecting the tip of the push button 33 34 and an opening 35 for opening the insertion port of the output terminal 14 are formed, and screw insertion holes 38 for fixing the upper case 2 to the lower case 3 with screws 36 and 37 are formed at both ends. Has been.

  Then, a transformer insertion for exposing a part of the current transformer 20 downward is provided on the bottom surface of the lower case 3 so that an electric wire can be inserted into the central opening 20a of the current transformer 20 from the outside of the case body 1. A hole 40 and a connection terminal insertion hole 41 for exposing the power connection terminal 21 are formed so that a power line for supplying power to the monitoring circuit unit 6 can be connected from the outside of the case body 1. Screw holes 42 and 43 for screwing with 36 and 37 and screw holes 44 for screwing a support frame 45 to be described later with screws 39 are formed.

  In addition, a support frame 45 that supports the display unit 10 and a push button 33 that pushes the switch 13 from above the upper case 2 and fixes the lower substrate 5 to the lower case 3 is disposed inside the upper case. ing. The support frame 45 is formed by processing a metal plate, and includes an engaging portion 46 that engages with both ends of the lower substrate 5, an insertion hole 47 through which the screw 39 is inserted, an insertion hole 48 through which the screw 37 is inserted, The opening 51 for projecting the upper part of the push button 33, the opening 52 for exposing the output terminal 14, the opening 53 for visually recognizing the digital display LED 10 from above, the screw 39 and the sound of the piezoelectric buzzer 22 are inserted. An opening 54 for discharge is formed.

  The push button 33 is urged by a spring 55, and the upper part penetrates the opening 51 of the support frame 45 and the opening 34 of the upper case 2 and is exposed to the upper surface of the upper case 2. It can be pushed.

  As shown in FIGS. 4A and 4B, the monitoring circuit unit 6 in which the upper substrate 4 and the lower substrate 5 are connected to each other by the support 25 and the printed circuit board 26 is connected to the power transformer 20 through the transformer insertion hole 40. The connection terminal 21 is set in the lower case 3 so as to be exposed from the connection terminal insertion hole 41, and the support frame 45 is covered so as to cover the monitoring circuit unit 6 while the spring 55 and the push button 33 correspond to the switch 13. With the joint portion 46 engaged with both ends of the lower substrate 5, the screw 39 inserted from the opening 54 of the support frame 45 is screwed into the screw hole 44 of the lower case 3 through the insertion hole 47, and the support frame 45 is lowered. After fixing on the case 3 and covering the digital display LED 10 with the transparent cover 30, the upper cover 2 is covered from above so as to cover the support frame 45, and the screw 36 is passed through the screw insertion hole 38 to the screw hole 42 of the lower case. Screwing By screwing the screw 37 into the screw hole 43 of the lower case 3 through the screw insertion hole 38 and the insertion hole 48, the monitoring circuit unit 6 can be fixed to the lower case 3 with the support frame 45, and the monitoring circuit unit in the upper case 2. 6 can be covered.

  FIG. 5 is a block diagram of the monitoring circuit unit 6. The monitoring circuit unit 6 converts the AC 100V into a DC 5V for driving the monitoring circuit unit 6, and the current detected by the current transformer 20. The true rms value calculation circuit 61 that calculates the true rms current value based on the calculation result, and the calculation result of the true rms value calculation circuit 61 is input to the control unit 12 as a voltage value and converted into a digital signal by the AD conversion circuit 63 The digital signal is converted into a 7-segment signal and displayed as a load current value on the 3-digit digital display LED 10. The control unit 12 is further connected to an output terminal (modular jack) 14 via a switch 13, a piezoelectric buzzer 22, and a photocoupler 64. By continuing to keep the switch 13 ON, a set current is sequentially applied to the digital display LED 10 every few seconds. When the display is switched (in this embodiment, six levels of 16, 18, 20, 24, 27, and 30A are set) and the switch 13 is turned off, the CPU 65 stores the display current at that time in the internal memory as a set value. It is like that.

  The CPU 65 compares and determines the measured current and the set current value. When the measured value current exceeds the set current value, the CPU 65 operates the piezoelectric buzzer 22 to generate an alarm sound to notify the user.

  On the other hand, the control unit 12 outputs the measurement current value as a measurement signal. The measurement signal is converted into a linearly changing voltage value and a signal isolated through the photocoupler 64 is output to the output terminal (modular jack) 14. The measurement signal can be output from the output terminal 14 to an external control device.

  How the measurement signal is used on the external control device side is left to the external control device side. For example, how much current flows through the current transformer 20 and the current being measured is set. Various processes can be performed such as whether the external control device can determine whether or not the current value has been exceeded. Moreover, since the current can be monitored even if the current monitoring unit and the external control device are separated from each other, for example, the load current of the electrical equipment such as a distribution board or an outlet equipped with the current monitoring unit is It is not necessary to go to the equipment side to check, and it is possible to deal with troubles in advance and centrally manage electrical equipment.

  According to the current monitoring unit A having the above-described configuration, when an electrical equipment device to which the current monitoring unit A is attached is used, the current flowing through the electrical equipment device is always displayed on the display unit 10, so that the situation can be easily grasped. When the set current value is changed, the set value is displayed on the display unit 10, so that the set value can be changed while checking the set value.

  When the measured current value exceeds the set value, the piezoelectric buzzer 22 outputs an alarm sound, so that it can be confirmed that the measured current exceeds the set value not only visually but also by hearing.

  Further, since the output terminal 14 for outputting the detected load current value as a measurement signal is provided, it is possible to connect an external control device such as a personal computer to the output terminal 14 and monitor it at a distance. In addition, the current monitoring unit A can monitor the current flowing through the load only by connecting AC 100V to the power connection terminal 21 and passing the current transformer 20 through one of the power lines for supplying power to the load. Therefore, it can be easily installed in the electrical equipment, and the current flowing through the installed electrical equipment can be easily monitored.

(A) (b) is a top view and a front view of a current monitoring unit according to the present invention. (A) (b) is a front view and a right side view of the monitoring circuit unit Exploded view explaining the configuration of the current monitoring unit (A) (b) is a front side longitudinal sectional view and a right side longitudinal sectional view of the current monitoring unit. Block diagram for explaining the electrical configuration of the current monitoring device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Case main body 2 Upper case 3 Lower case 4 Upper board 5 Lower board 6 Monitoring circuit part 10 Display part (digital display LED)
12 Control Unit 13 Switch 20 Current Transformer 21 Power Connection Terminal 22 Alarm Buzzer (Piezoelectric Buzzer)
24 connecting means 33 push button 40 transformer insertion hole 41 connection terminal insertion hole 45 support frame

Claims (2)

A case body composed of an upper case and a lower case;
A monitoring circuit unit composed of an upper substrate and a lower substrate that are connected to each other with a connecting means in the case body at an interval in the vertical direction,
A current transformer partially exposed to the outside from the transformer insertion hole formed in the case body;
An alarm buzzer that issues an alarm when the load current applied to the electric wire inserted outside the case body exceeds the set value;
A display unit mounted on the upper substrate for digitally displaying a load current value; a switch mounted on the upper substrate for switching the setting value;
A power connection terminal exposed from a connection terminal insertion hole drilled in the case body for supplying power to the monitoring circuit unit;
A digital display current monitoring unit comprising: a support frame for supporting the display unit and a push button for pressing and operating the switch, and a support frame for fixing the lower substrate to the lower case inside the upper case.   The digital display current monitoring unit according to claim 1, wherein the case body is provided with an output terminal for outputting a load current value to an external control device.

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