JPS61136107A - One-loop controller - Google Patents

Abstract

PURPOSE:To attain the simultaneous monitor with data important for control by displaying freely an optional data on a front panel in a working mode. CONSTITUTION:A display request item code 150 read by a set data input program 100 stored in an ROM 2 is stored to an RAM 3. A data display processing program 200 stored in the ROM 2 reads the corresponding data out of the process data or the arithmetic data 151 in accordance with the code 150 and displays it to a numerical value display device 9 on the front panel through a display interface 8. When no display request item is designated, a process variable PV is displayed to the numerical display value 94 based on the control target value SV. Thus the use like a conventional example is also possible.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention controls the opening degree of a valve that adjusts the flow rate of fluid, detects the flow rate that actually flows through a flow path with a sensor, and uses this as negative feedback. - Concerning a closed-loop controller.

[Technical background of invention■ and its problems]

One-loop controllers are generally equipped with an analog meter and an LED bar display on the front panel to display control target value Sv, process variable PV, m-production output MV, etc. Recently, one-loop controllers have been equipped with an analog meter and an LED bar display on the front panel, and display the control target value Sv, process variable PV, m production output MV, etc. hand,
There are now machines equipped with a numerical display that displays the control 14 standard value Sv, process variable PV, etc. in industrial units with high precision.

A front panel view of this type of conventional device is shown in FIG.

300 is the front panel, 301 is an analog meter, 302
is 1 - index of control target value SV, 303 is process change @P
V index, 304, control 21I target value SV setter, 3
05 is a digital display that digitally displays the numerical value of the analog meter 301, and 306 is a digital display 305.
To display the display, select the variable P■ or 111I.
Button to switch whether to select target msv, 307
is a meter for the manipulated output MV, 308 is an increase/decrease adjuster for the manipulated output MV (turning it to the INC side increases it, turning it to the DEC side decreases it), 309 is an automatic switching device (M is the manual adjustment side, A is the automatic adjustment side) ).

However, with these controllers, only fixed data items such as the control aueA value S, process variable PV, and manipulated output MV are displayed on the numerical display, and in order to display other controller information, settings and displays on the side are required. It is necessary to extract the controller from the device each time a device is used, and it is not possible to simultaneously display and continuously monitor the process variable PV and other data important for control.

Adding a numerical display for uses other than process variable PV is generally difficult due to Noh mask panel size constraints.

(Object of the Invention) The present invention overcomes the drawbacks of conventional devices and allows arbitrary data inside the controller to be specified as display items on the numerical display on the front panel. For example, we provide a one-loop controller that can monitor process variables P and other data important for control without having to draw out the panel by setting and displaying data items on the side. , its purpose.

(Summary of the Invention) The present invention comprises a calculation means consisting of a microcomputer, and a display means for representing control target values and process variables in analog form;
A numeric display that does not show digital values is provided on the front of the controller, and a data item setting device that displays arbitrary data inside the controller on the numeric display is provided, for example, on the side of the controller, and settings can be made using the setting data input function means. This is a one-loop controller that stores the requested display item code in the memory, reads out process data or calculation data according to the display requested item code using the data display processing function, and extracts and displays the data on the numerical display.

(Embodiment of the Invention) A block diagram showing a circuit configuration in an embodiment of the invention is shown in FIG.

1 is a central processing unit (CPU) that controls information exchange and calculations;
2 is a read-only memory (('(OM)) in which programs for process input/output processing, control algorithms, setting data input, and data display processing are stored; 3 is a data item setter for control constants, process data, calculation data, etc. a read/write memory (RAM) for storing display items on the numerical display 94 on the front panel designated by 6;
5 is a bus (internal bus) for data transmission inside the controller; 5 is an interface (keyboard/display interface) with the data item setter 6 and display 7 mounted on the side; 8 is a display 9 mounted on the front panel 9.
1 to 94 (display interface), 1° is an interface (process input/output interface) that relays the bus signal input from the center height 12 and the operation output to the operation end (valve 11), 91
．． 92 and 93 are LED bar displays that display the process variable P■, control target value S■, and operation output MV in analog form, respectively.94 is set in the data item setting device 6 and digitally displays the data extracted after calculation. It is a numeric display device.

Note that the data item setting device is equipped with a numeric keypad, etc., and for example, the control target value S of the fluid to be
(3) and the mixing ratio of a plurality of fluids are set, and the result of the calculation is displayed on the display 7 in digital form.

The data specified on the keyboard/display unit attached to the side of the controller, that is, inputted using the data item setter 6, is sent to the CPU 1 via the interface 5. ROM
2. The request item code to be displayed on the numerical display 94 of the front panel 9, which is processed in the RAM 3 and displayed on the display 7, is processed as follows.

That is, calculations are performed according to the chart shown in FIG.

The display request item code 150 read by the setting data input program 100 in the ROM2 is stored in the RAM3.

The data display processing program 200 in the ROM2 is
According to the display request item code 150 stored in M3,
The corresponding data is read out from the process data or calculation data 151 (204) and displayed on the numerical display 9 on the front panel through the display interface 8.

In addition, if the display request item is not specified (<205), the control item Ia value SV or the process variable Pv is displayed on the field display 9.
4, so it can be used like the conventional example.

With the above, the operator can determine the process variable Pv and other ! 1
1011 and important data can be monitored simultaneously on the front panel 9.

〔Effect of the invention〕

Important data items for υ control differ depending on the application system, and even in the same system, they often change depending on the operating state.

Thus, according to the present invention, the advantage of being able to freely designate display of any data on the front panel in the operating state is extremely large, and contributes to the field in many ways.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the circuit configuration in one embodiment of the present invention, and FIG. 2 is a block diagram showing the circuit configuration in an embodiment of the present invention. A flowchart showing J11¥, FIG. 3 is an explanatory diagram of a conventional example. 1...CPU, 2...ROM, 3...RAM, 4
...Internal bus, 5.8.10...Interface, 6...Data item setter, 7...Display device, 9...
・Front panel, 11... Valve, 12... Sensor.

Claims (1)

[Claims] 1. A calculation means consisting of a CPU, ROM, and RAM and an interface connecting these to the outside are provided, and a display means for representing control target values and process variables in analog form, and a numerical display for showing digital values. is arranged on the front of the controller, and a data item setting device is provided to display arbitrary data inside the controller on the numerical display, and the display request item code set by the setting data input function means is stored in the RAM, and the data display is performed. A one-loop controller characterized in that a processing function means reads out process data detected from a process or calculated data obtained from a calculation means according to a display request item code, and extracts and displays the data on a numerical display.