JPH0410675B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to improvements in indicator and alarm meters used in process instrumentation and other technical fields.

[Technical background of the invention]

This type of indicator/alarm meter is used in various technical fields; for example, in the field of plant instrumentation, those having configurations as shown in FIGS. 6 and 7 are used. The indicator/alarm meter shown in FIG. 6 has a bar graph-shaped indicator 2 and an alarm operating point (hereinafter, the alarm operating point is abbreviated as "alarm point") on one side of the panel of the instrument body.
In the drawings, these points are also abbreviated as warning points. ) A changing volume 3 is installed, and this alarm point changing volume 3 allows you to change alarm points for one input signal, such as upper limit, lower limit, or a combination of both, such as upper limit/lower limit, upper limit/upper upper limit, lower limit/lower lower limit, etc. It is now possible to change the settings. 2a and 2b indicate upper and lower alarm points that are moved and displayed by operating volume 3;
is an alarm display section such as an LED that lights up to notify the operator when the input signal level exceeds the alarm point 2a or 2b.

The indicator/alarm meter shown in Figure 7 has a volume 3 for changing the alarm point not on the front panel 1 but on the side of the meter body.
It has been established.

[Problems with background technology]

However, the indicator/alarm meter configured as described above has the following problems.

A volume 3 is used as a means for changing the alarm points 2a and 2b, and since this volume 3 has a structure in which a slider slides on a resistance element,
Failures such as poor contact and disconnection are likely to occur, resulting in a lack of reliability.

If necessary, for example, it may be necessary to prohibit changes to the highest and lowest alarm points 2a and 2b, but in this case a mechanical locking mechanism must be added to the volume itself, which increases the number of mechanical configurations and reduces reliability. Sexuality decreases.

In addition, as the alarm types of alarm points 2a and 2b,
It is necessary to judge whether it is an upper limit/lower limit, an upper limit/upper upper limit, or a lower limit/lower lower limit, but since only the alarm points 2a and 2b are displayed on the bar graph indicator 2, the alarm is not generated. At this time, it is not possible to determine what type of alarm it is.

That is, for example, an upper limit alarm in the case of the upper limit/upper upper limit alarm type and a lower limit alarm in the case of the lower limit/lower limit alarm type cannot be distinguished on the panel unless the alarm type is displayed at the time of the alarm occurrence.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned circumstances, and uses components that change the alarm point that are less likely to fail or change over time to improve the reliability of the instrument, and to make it easier to identify the alarm type when an alarm occurs. The purpose of this invention is to provide an indicator and alarm meter that

[Summary of the invention]

The present invention uses an alarm point display request switch, an alarm point change switch with an on/off function, and an alarm type designation switch for each alarm type, and determines whether or not there is an alarm point display request based on a predetermined routine. If there is a request, the alarm point data is displayed on the indicator simultaneously or separately from the input signal, the state of the alarm type designation switch is read and the corresponding alarm type display section is lit, and the alarm point change switch is activated. This is an indicator alarm meter that reads the status of the alarm and changes the alarm point data.

[Embodiments of the invention]

Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 5. FIG. 1 is an external perspective view of an embodiment of the indicator/alarm meter according to the present invention, in which a vertical indicator 12 in the form of a bar graph, for example, is provided on the left side of the center of the front panel 11. On the other hand, on the right side of the center of the front panel 11, the UPPER side alarm point is changed to move the alarm point on the upper limit side of the upper/lower limit alarm, or the upper limit side of the upper/upper upper limit alarm, or the lower limit side of the lower/lower limit alarm, up or down. switch 13
H, 13L, Alarm point display request switch 14 and LOWER side alarm point change to move up and down the alarm point on the lower limit side of the upper/lower limit alarm, or the upper limit side of the upper/upper upper limit alarm, or the lower limit side of the lower/lower limit alarm. Switches 15H and 15L are sequentially arranged from the upper side to the lower side at a predetermined interval. Reference numeral 16 denotes an alarm type display section for displaying the alarm type, and this is made up of, for example, above the switch 15H and in the width direction of the panel, a number of LEDs (light emitting diodes) equal to the number of alarm types are arranged. Also, the side part 1 of the instrument body
An alarm type designation switch 18 and an alarm point lock switch 19 are provided on the 7 side. Note that FIGS. 2A and 2B show the display forms of the alarm points 12a and 12b in the instruction section 12, respectively.

Next, FIG. 3 is a block diagram of the entire indicator/alarm meter including the electrical and mechanical components 12 to 16, 18, and 19 as described above. In the figure, reference numeral 21 denotes a signal processing section composed of, for example, a microcomputer, which includes a central processing unit (hereinafter referred to as CPU), a timer, and, if necessary, a storage section and other elements. An A/D conversion circuit 22 that converts an analog input signal into a digital signal is connected to this signal processing section 21. Further, the signal processing section 21 is connected to a switch input port 23 that functions as an interface and a lamp output port 24 that converts data output from the signal processing section 21 into a required lamp drive signal and outputs the signal. Reference numeral 25 denotes an alarm data storage section that stores data on the presence or absence of an alarm point display request, alarm point data, etc., and is connected to the signal processing section 21. Reference numeral 26 denotes an instruction section driving circuit which is also connected to the signal processing section 21 and is composed of a display data register, a shift register and other elements, and is capable of displaying as shown in FIG. 2A or B. 27 is an alarm output section, which is connected to a plant safety protection device or external equipment such as a lamp or a buzzer.

Next, the operation of the indicator/alarm meter configured as above will be explained.

(1) Input signal display processing The signal processing section 21 reads the digital signal corresponding to the analog input signal SA converted by the A/D conversion circuit 22 at predetermined intervals, and stores it in its own storage section as necessary. Thereafter, it is sent to the instruction section drive circuit 26. This indicator drive circuit 2
In step 6, the contents of the display data register are transferred to the shift register, and the lighting of LEDs and the like is controlled in the form of a bar graph or point. Instruction section 12
can display the analog input signal level.

(2) Alarm point data display processing This alarm point data display processing is performed by the signal processing unit 2.
For example, every 200 msec, the 4th
This is done according to the flow shown in the figure. In this process, alarm point data is stored in the alarm data storage section 25 in advance. Note that when using the meter for the first time, an initial value alarm point is given. For example, in the case of the upper/lower limit alarm type, data of upper limit H=100% and lower limit L=0% is given as data.

When the alarm point data display command S1 is activated every 200 msec in the above state, the signal processing section 21 reads the on/off state of the alarm point display request switch 14, which is one of the contents of the switch input port 23. Then, it is determined whether a new alarm point display request has occurred (step S2).
If it is determined that a new occurrence has occurred, the alarm point display flag of the corresponding storage element in the alarm data storage section 25 is inverted. That is, the initial value of the alarm point display flag is "0", and when there is a request for alarm point display, it changes to "1".
The display will be highlighted, and it will be remembered that there is a request to display the alarm point. (Step S3). Therefore, when the alarm point display request switch 14 is turned on again next time, the alarm point display flag is inverted to "0" again.

Next, in step S4, it is determined by reading whether the content of the alarm point display flag is "1" or "0". If it is determined in step S2 that no new warning point display request has occurred, the process jumps to step S4 and directly determines the contents of the warning point display flag. If this flag is "0", the process moves to the input signal display process in item (1) above, where the input signal SA is supplied to the instruction section drive circuit 26 and displayed on the instruction section 12 (step S
5). If the flag is "1", it is determined that a warning point display request has already been made, and the process proceeds to step S6.
to move to.

In this step S6, the signal processing section 21
The CPU reads alarm point data from the alarm data storage section 25, supplies it to the instruction section drive circuit 26, and displays it, for example, as shown in FIG. 2A or FIG. 2B. Subsequently, after supplying the alarm point data to the instruction section drive circuit 26, the process moves to step S7. Here, the CPU of the signal processing unit 21 reads the contents of the switch input port 23, checks which alarm type designation switch 18 is turned on,
The alarm type display section 16 corresponding to the switch 18 that is turned on is displayed.

(3) Judgment and output of alarm The signal processing section 21 compares the input signal and the alarm point data, and when it judges that the input signal level exceeds the alarm point, sends a signal to that effect to the alarm output section 27. Send. Therefore, the alarm output section 27 receives the signal and transmits an alarm output to the outside.
Also, when an alarm occurs, the LED on the alarm type display section blinks to notify the alarm occurrence.

(4) Alarm point change processing Before or after alarm point data display processing, the fifth
The alarm point change process shown in the figure is performed. That is,
When the alarm point change command S11 is activated, the CPU of the signal processing section 21 determines whether the flag of the corresponding storage element in the alarm data storage section 25 is "1" or "0" (step S12), and sets the flag to "1". In this case, the CPU reads the contents of the switch input port 23, especially the on/off state of the alarm point lock switch 19 (step S13), and does not change the alarm point data when the alarm point is locked, but when the alarm point is unlocked or After unlocking
Similarly, the contents of the switch input port 23, especially the alarm point change switches 13H and 1, are controlled by the CPU.
The on/off states of 3L, 15H, and 15L are read, and if any switch is on, the alarm point data is changed by increasing or decreasing the numerical value of the alarm point data corresponding to that switch by a predetermined value (step S14).

When changing from the alarm point data display state to the normal input signal display state, for example, the alarm point display request switch 14 is pressed again to return to the original state.

Therefore, according to the above configuration, since on/off switches are used as the alarm point change switches 13H, 13L, 15H, and 15L, there are no failures due to poor contact unlike with volume controls, and reliability is improved. . Furthermore, since the signal processing section 21 handles changes to the alarm point, it is possible to use one simple switch and read the on/off state of the switch to determine whether or not to change the alarm point. In addition, an alarm type designation switch 18 is provided, and the signal processing unit 21 reads the on/off state of the switch 18 and drives and displays the alarm type display unit 16 corresponding to the on switch 18. Therefore, the alarm point data of which alarm type You can immediately know if there is one.

Note that the present invention is not limited to the above embodiments. For example, when a warning point display is requested, the warning points shown in FIG. 2A may be displayed superimposed on the input signal display. In this case, the input signal level can be monitored even while the alarm point is being displayed or changed. Also, when an alarm occurs, the alarm type display section
In addition to blinking the LED, the input signal display may blink or the display shown in FIG. 2B may blink. This has the effect of making the operator immediately aware of the abnormality. In addition, the present invention can be implemented with various modifications without departing from the gist thereof.

〔Effect of the invention〕

As described in detail above, according to the present invention, the alarm point can be changed using a switch that has an on/off function, so there are fewer failures compared to conventional volume switches, and reliability can be improved. It is possible to provide an indicator alarm meter that allows you to immediately know what kind of alarm is occurring.

[Brief explanation of drawings]

Figures 1 to 5 are shown to explain one embodiment of the indicator/alarm meter according to the present invention.
The figure is a perspective view of the external appearance of the indicator/alarm meter, Figure 2 is a display state diagram of alarm point data in the indicator, Figure 3 is a configuration diagram showing the entire indicator/alarm meter, and Figure 4 is a flowchart of alarm point data display processing. FIG. 5 is a flowchart of a process for changing alarm point data, and FIGS. 6 and 7 are external perspective views of conventional indicator and alarm meters, respectively. 12...Instruction section, 13H, 13L, 15H, 1
5L...Alarm point change switch, 14...Alarm point display request switch, 18...Alarm type designation switch, 19...Alarm point lock switch, 21...Signal processing section, 23...Switch input port, 24...
... Lamp output port, 25 ... Alarm data storage section, 26 ... Indicator drive circuit, 27 ... Alarm output section.

Claims (1)

[Scope of Claims] 1. An indicator/alarm meter that displays an alarm operating point of the input signal level on an indicator that displays the level of the input signal, and changes and displays this alarm operating point as necessary, comprising: An alarm operating point change switch that outputs an on/off signal to change the operating point, an alarm operating point display request switch that outputs an alarm operating point display request signal when display of the alarm operating point is required, and a periodic automatically or arbitrarily determines whether or not there is a request to display the alarm operating point, and if there is a display request, reads the alarm operating point data stored in the alarm data storage section and displays it on the instruction section. The operating point display control means and the on/off state of the alarm operating point changing switch are read, and when the alarm operating point changing switch is turned on, the alarm operating point data stored in the alarm data storage section corresponding to the alarm operating point changing switch is read. An indicator/alarm meter comprising a control means for changing an alarm operating point. 2. The alarm operating point display control means includes an alarm type designation switch for specifying the alarm type and an alarm type display section for displaying the alarm type, and displays the alarm operating point and alarm type at the same time when alarm operating point display is requested. An indicator/alarm meter according to claim 1, characterized in that: 3. The alarm operating point display control means shall cause the instruction unit to
The indicator/alarm meter according to claim 1, wherein the input signal level is normally displayed, and the alarm operating point data is displayed when an alarm operating point display is requested. 4 The alarm operating point display control means shall cause the instruction unit to
The indicator/alarm meter according to claim 1, wherein the input signal level is normally displayed, and when the alarm operating point display is requested, the input signal level and alarm operating point data are displayed simultaneously. 5. The instruction alarm according to claim 4, wherein the means for simultaneously displaying the input signal level and the alarm operating point data displays the input signal level in a bar graph form and the alarm operating point data in a point form. Total. 6. The indicator alarm meter according to claim 1, wherein the alarm operating point change control means includes a lock switch that prohibits changing the alarm operating point.