JP4275271B2 - Measurement display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a multi-type measurement display device capable of switching and displaying measured values such as current, voltage, and power by operating a push button.
[0002]
[Prior art]
There is a measuring device having a multi-display function that displays various measurement values such as current, voltage, power, and power factor on a single display device by pressing a push button as necessary. Such measurement devices, especially multi-type measurement display devices attached to switchboards, etc., are not frequently switched and displayed. Therefore, in consideration of space and cost, the number of push buttons is reduced as much as possible, and multiple push buttons are provided. Often have a selection function.
[0003]
In addition, a multi-type measurement display device used for such a switchboard always displays a predetermined display item (hereinafter referred to as a constant display measurement item), and an operator switches the display item as necessary. Often used to read necessary measurements. In this type of conventional measurement display device, each time the switch button is pressed, the display items are sequentially switched, and the display items are continuously displayed for a predetermined time unless the button is pressed. Some display items are always displayed.
[0004]
[Problems to be solved by the invention]
The conventional multi-type measurement display device is a fixed device in which the always-displayed measurement item is determined at the time of production. Therefore, it is impossible even if the operator wants to change another item to the always-displayed measurement item.
[0005]
Therefore, this invention is providing the measurement display apparatus which can change a display measurement item freely always.
[0006]
[Means for Solving the Problems]
In order to solve the above-described problem, the present invention stores a measurement value in a measurement display device that constantly measures a plurality of measurement items, selects a measurement item at any time, and displays the measurement value. A display that displays the measured value, a first push button that sequentially switches the item of the measured value that is displayed each time it is operated, and a rewritable non-volatile that writes a constantly displayed measurement item that displays the measured value at all times A storage means, a second push button for changing the constantly displayed measurement item, a means for switching the item of the measured value displayed when the predetermined operation is not performed for the first predetermined time, to the always displayed measurement item; When the measurement value of the measurement item is displayed and the second push button is continuously pressed for a second predetermined time or longer, the constantly displayed measurement item stored in the nonvolatile storage means is set as the arbitrary measurement item. Means to rewrite, We are going to prepare.
[0007]
With such a configuration, the measurement item of the measurement value to be displayed can be switched by operating the first push button, and if a state in which the predetermined operation is not performed for the first predetermined time or longer continues, it is set in advance. The measurement value of the always displayed measurement item is automatically displayed. Further, when the second button is kept pressed for a second predetermined time or more while the measurement value of an arbitrary measurement item is displayed, the constantly displayed measurement item can be changed to the arbitrary measurement item.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the examples shown in FIGS.
FIG. 1 shows a hardware configuration diagram of this embodiment, and a current signal conversion circuit 3 and a voltage signal for rectifying a current signal and a voltage signal obtained from a current transformer 1 and a transformer 2 provided in a power path. CPU 5 for inputting signals converted in conversion circuit 4, current signal conversion circuit 3 and voltage signal conversion circuit 4, non-volatile EEPROM 6 in which constant display measurement items to be described later are written, and various measurement values stored in CPU 5 to be described later. A 7-segment numerical display 7 for selective display, an item display LED 8 for displaying the displayed measurement items, four push buttons 9, 10, 11, 12 and a stabilized power supply 13 for operating this device And a transmission signal interface 14 for transmitting the measurement value to another device, although the description thereof is omitted because it is not directly related to the present invention.
[0009]
This measurement display device can display (1) current value, (2) voltage value, (3) instantaneous power value, (4) integrated power value, and (5) power factor value of the power path. Each time the button 9 is pressed, the display items are changed in the order of ▲ 1 →→ 2 ▼ .... → 5 ▼ → ▲ 1 ▼ → ▲ 2 ▼ .... 1 ▼ → ▲ 5 ▼ → ▲ 4 ▼ → ・ ・ → ▲ 1 ▼ → ▲ 5 ▼ → ▲ 4 ▼ →. (Pushbuttons 9 and 10 are first pushbuttons having the same function.) In addition, when the display item is a current value, pushbutton 11 has a three-phase power path (A phase each time it is pressed).・ A function to sequentially switch and display the phases of B phase and C phase, and a function to shift to a reset process to return the display value to zero when the display item is accumulated power when pressed for a predetermined time (T3) or longer. Have. Furthermore, in addition to the function of canceling the integrated power reset process described above, the push button 12 switches an arbitrary display item currently displayed to a constantly displayed measurement item, which will be described later, or changes a constantly displayed measurement item. It has a function.
[0010]
The above-mentioned constantly displayed measurement item is a display item stored in advance in the EEPROM 6, and when any of the push buttons 9, 10, 11 and 12 is not operated at all for the first predetermined time (T1), the automatic measurement is automatically performed. Accordingly, the measurement value of the constantly displayed measurement item is displayed. The constantly displayed measurement item can be changed to a desired item as follows. That is, when the push button 9 or 10 is operated to display the measurement value of a desired display item, and the push button 12 (second push button) is pressed for a second predetermined time (T2) or longer while the push button 9 or 10 is displayed. The display item written in the EEPROM can be rewritten to a desired display item.
[0011]
2 to 4 are flowcharts of operations performed in the CPU 5 of this apparatus. The operations of this apparatus will be described with reference to these drawings. The CPU 5 performs two main tasks, the main task shown in FIG. 2 and the button operation processing task shown in FIG. 3, simultaneously and asynchronously.
[0012]
In FIG. 3, the task loop for monitoring the operation state of the buttons sequentially checks whether or not the push button 9 or 10 (hereinafter referred to as push button 9) is pressed (S3-1). It is confirmed whether it has been pushed (S3-2), whether the pushbutton 12 has been pushed (S3-3), and whether any pushbutton has been pushed for the first predetermined time (T1) is confirmed (S3). -4) and the loop of returning to (S3-1) is repeated.
[0013]
In the loop of FIG. 3, when the push button 9 is pressed in (S3-1), the information of "event occurrence of push button 9" is stored in the RAM of the CPU 5 after waiting until the button is released, and (S3- When the push button 11 is pressed in 2), the pressed time is measured, and when it is equal to or longer than the predetermined time (T3), the information of “the occurrence of the event of the push button 11 / T3” is displayed for the predetermined time (T3). If it is less than that, the information of “event occurrence of push button 11” is stored in the RAM of the CPU 5. Further, when the push button 12 is pressed in (S3-3), the time during which the push button 12 is pressed is measured. When the time is less than the time (T2), the information “event occurrence of the push button 12” is stored in the RAM of the CPU 5, and no push button is pressed for the first predetermined time (T1) in (S3-4). Stores information of “no operation event occurrence” in the RAM of the CPU 5.
[0014]
In FIG. 2, the main task loop reads the constantly displayed measurement items written in the EEPROM in the initialization process, and inputs the respective signals from the current signal conversion circuit 3 and the voltage signal conversion circuit 4 (S2-1). The instantaneous power value, integrated power value, and power factor are calculated from the input current signal and voltage signal, and the current value and voltage value are calculated as effective values as necessary, and then stored (S2- 2) The measurement value of the designated display item (the initial display value is the measurement value of the constantly displayed measurement item) is displayed (S2-3), and event information obtained by operating the buttons described in FIG. S2-4).
[0015]
Then, the presence or absence of the information “event occurrence of push button 9” is confirmed (S2-5), and if there is, the display item is changed according to the instruction. Next, the presence / absence of information on “event occurrence of push button 11” is confirmed (S2-6). If there is information and the display item is a current value, the phase is changed according to the instruction. Next, the presence / absence of the information “event occurrence of push button 11 / T3” is confirmed (S2-7), and if there is information and the display item is the integrated power value, the process proceeds to the reset process. Next, the presence / absence of information on “event occurrence of push button 12” is confirmed (S2-8), and if present, the current display item is changed to a constantly displayed measurement item. Next, the presence / absence of the “push button 12 / T2 event occurrence” information is confirmed (S2-9), and if present, the currently displayed display item is always stored in the RAM as a display measurement item and written to the EEPROM. . Next, the presence / absence of “no operation event occurrence” information is confirmed (S2-10), and if present, the current display item is changed to a constantly displayed measurement item, and a loop of returning to (S2-1) is repeated. .
[0016]
Although the embodiment of the present invention has been described above, the embodiment of the present invention disclosed above is merely an example, and the scope of the present invention is limited to the embodiment of the above invention. It is not something. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.
[0017]
【The invention's effect】
Since the present invention is configured as described above, the display item of the measurement display device for selecting and displaying the measurement values of a plurality of measurement items as needed is displayed when the display item switching operation is not performed for a certain period of time. Has a function of automatically switching to a preset always-displayed measurement item, so that it is possible to freely change the always-displayed measurement item, so that the operator's workability is improved. Even if the operating power supply is once lost and then supplied again, the measurement value of the display item selected immediately before the power supply loss is displayed, so that the operator can prevent misidentification.
[Brief description of the drawings]
FIG. 1 is a hardware configuration diagram of an embodiment of a measurement display device according to the present invention.
FIG. 2 is a flowchart of the embodiment of FIG.
FIG. 3 is another flowchart of the embodiment of FIG. 1;
[Explanation of symbols]
3 Current signal conversion circuit 4 Voltage signal conversion circuit 5 CPU
6 EEPROM
Numeric display 9, 10, 11, 12 Pushbutton

Claims (1)

In a measurement display device that constantly measures a plurality of measurement items, displays the measurement values by selecting the measurement items as needed,
Means for storing the measured value;
A display for displaying the stored measurement value;
A first push button for sequentially switching the measurement value items displayed each time the operation is performed;
A rewritable non-volatile storage means in which measurement items that are always displayed for displaying measurement values are written,
A second push button for changing the constantly displayed measurement item;
Means for switching the item of the measured value displayed when the predetermined operation is not performed for the first predetermined time to the constantly displayed measurement item;
When the measurement value of an arbitrary measurement item is displayed and the second push button is continuously pressed for a second predetermined time or longer, the constantly displayed measurement item stored in the nonvolatile storage means is Means to rewrite to any measurement item;
Measurement display means characterized by comprising:

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