JPH04275601A - Digital indicating controller - Google Patents

Abstract

PURPOSE:To easily set many parameters and functions with the same feeling with the operation on a personal computer by making the constitution of the front panel or console panel surface of the controller simple and connecting external equipment. CONSTITUTION:The controller is provided with a connection terminal 3 for coupling the external equipment 3 with a man-machine interface function and an interface 5 for transmitting and receiving a data base 6 to and from the external equipment 3 through this connection terminal 2. This external equipment 3 is provided with a parameter setting display means 31 which accesses the memory on the controller side through the connection terminal 2 and displays and resets parameters regarding control arithmetic and a parameter loading means 32 for loading the reset parameters in the memory 6.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is used for temperature control of furnaces and thermostats, and has display means on the front panel or operation panel for digitally displaying process quantities, target set values, etc. necessary for control. The present invention relates to a digital indicating controller, and more particularly to a digital indicating controller that allows various parameters to be displayed and changed by an external device having a man-machine interface function such as a general-purpose personal computer.

0002

[Prior Art] A simple controller used for controlling the temperature of a furnace or thermostatic oven inputs a temperature signal (process amount) from a sensor, and the temperature of the oven or thermostatic oven is set at a set temperature (target set value). proportional to the deviation signal (P) so that
, integral (I), differential (D) calculation, or on/off calculation, and is configured to send a control output signal to a load such as a heater. When a user purchases a digital indicating controller configured in this manner and connects it to a process to operate it, various parameters (for example, PID calculation parameters,
It is necessary to check, set, and change the upper and lower alarm limits, the range depending on the sensor type, etc. Conventionally, this type of digital indicating controller is equipped with a dedicated keyboard and display (instruction) means for setting various parameters.
They were configured so that an operator could operate them as needed.

0003

[Problem to be Solved by the Invention] However, in conventional digital indicating controllers with such a configuration, the configuration becomes complicated because many types of keys are lined up for setting various parameters on the meter. Additionally, keys that are not used in normal control operation are mixed, and the operator has to be aware of the existence of the keys that are not used when operating the keys. There are also devices that reduce the number of keys and share them with various functions, but this results in problems such as complicated operations and limited operations. The present invention has been developed in view of these circumstances, and it reduces the number of types of operation keys and allows a user operator who does not have knowledge of control theory to easily operate the machine. The purpose of the present invention is to provide a digital indicating controller in which many parameters and functions can be easily set as necessary using external equipment.

0004

[Means for Solving the Problems] The present invention achieves the above object by providing a display means on the front panel for digitally displaying the process quantity and the target set value, and storing the deviation between the process quantity and the target set value in a memory. In a digital indicating controller that performs control calculations based on parameters stored in the controller and outputs the control output to the process, the controller includes a connecting terminal for connecting to an external device having a man-machine interface function, and a connecting terminal for connecting the connecting terminal to an external device having a man-machine interface function. An interface for transmitting and receiving a database with an external device is provided through the interface, and the external device can access the memory on the controller side through the connection terminal to display and display parameters related to control calculations.
The apparatus includes a parameter setting display means for changing settings, and a parameter loading means for loading the changed parameters into the memory.

[0005]

[Operation] By connecting an external device to the connection terminal, the database can be accessed from the external device, and various parameters related to control calculations can be displayed and settings changed using the external device's man-machine interface function. becomes possible.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, 1 indicates the front panel of the controller, which shows the process amount P under normal operating conditions.
Display means 11 and 12 are provided for digitally displaying V and target set value SP. Also, there is an up key 13 for increasing the set value SP, a down key 14 for decreasing it, a set/enter key 15 for selecting data settings or parameters, and an A/enter key for switching between automatic adjustment and manual adjustment. A keyboard 10 having an M key 16 and the like is provided. A connection terminal 2 is provided on the front panel 1 to enable connection with external equipment. 3 is an external device having a man-machine interface function that is connected to the connection terminal 2 via a lead wire. As this external device, a personal computer, an electronic notebook, etc. can be used. Here, the connection terminal 2 provided on the external device 3 and the controller
For example, data exchange performed via RS23
It is assumed that this is carried out in a standardized signal format such as 2C.

Reference numeral 4 generally shows a microprocessor provided inside the controller. This microprocessor 4 has a display control function (means) 41 for digital display means 11 and 12, an up key 13, and a down key 1.
an up/down counter 42 that receives signals from the keyboard 10 and adds or subtracts a clock depending on the time that these keys are pressed; a keyboard interface 43 that receives signals from the keyboard 10; and a control calculation means that performs calculations such as PID control calculations. 44, control parameter setting means 46 for setting various control parameters used in this control calculation means 44; set value output for outputting a set value signal corresponding to the set value SP displayed on the display means 12 to the control calculation means 44; Functions such as the means 47 are realized by a program.

5 is an interface with external equipment 3;
External device 3 connected to connection terminal 2 and, for example, RS232
This is for exchanging data in a standardized signal format such as C. 6 is a memory in which a database is stored, and 7 is an A/D converter, which converts an analog signal from a temperature sensor installed in the process into a digital signal, for example. 8 is a signal output means, which converts the control output obtained by the control calculation means 44 into a pulse width signal or 4 to 20 m
It is used to convert and output a signal capable of driving a load such as A. As the load, a thyristor or the like is used to control the power supplied to the heater. The external device interface 5, memory 6, and A/D converter 7 are all connected to the microprocessor 4 via a bus.
It is connected to the. In the external device 3, 31 displays various parameters read from the memory 6 on the controller side via the connection terminal 2 on a screen 30 provided in the external device 3 and functions as a man-machine interface, and also sets them. This is a parameter setting display means. 32 is a parameter loading means for loading various parameters displayed on the screen into the memory 6 based on specifications; 33 is a means for loading process quantities and control outputs on the screen 30 according to specifications;
This is a trend graph display means that displays target set values and the like as a trend graph. Each of these means is realized by software of an external device.

[0009] The operation of the apparatus constructed in this way will be explained next. First, in the normal control operation mode, the display means 11 displays the process amount PV by the display control means 41.
is displayed, and the target setting value SP is displayed on the display means 12.
is displayed. The display of the process amount PV corresponds to the signal from the sensor applied via the A/D converter 7, and the display of the target set value SP corresponds to the value output by the set value output means 47. are doing. From this kind of situation,
Up key 13 or down key 1 in keyboard 10
When 4 is pressed, those signals are applied to the up/down counter 42 via the keyboard interface 43, and the value of the up/down counter 42 increases or decreases accordingly, and the value of the target setpoint SP also increases or decreases. change to decrease. When the value displayed on the display means 12 reaches the target value, release the up key 13 or down key 14, confirm that the displayed value is correct, and then press the set/enter key 15. As a result, the target set value newly displayed on the display means 12 is outputted from the set value output means 47 to the control calculation means 44.

The control calculation means 44 inputs the process signal PV applied via the A/D converter 7 and the set value signal SP from the set value output means 47, and inputs, for example, a PID signal to these deviation signals. It performs control calculations and outputs the control output to the load via the signal output means 8. Here, data of various parameters such as various calculation parameters used by the control calculation means 44, upper and lower limit values, and ranges depending on the type of sensor are stored in the memory 6, and data of various parameters used by the control calculation means 44 are stored in the memory 6. 46 reads them and sets them in the control calculation means 44. When attempting to adjust the load manually, press the automatic/manual switching key 16 in the keyboard 10 to enter manual adjustment mode. When this manual adjustment mode is entered, the display 17 indicates that the manual mode is activated.
It becomes possible to manually adjust the load by operating the up key 13 or the down key 14. In this case, the manual output value is determined using, for example, the display means 12, and the value displayed there is outputted from the signal output means 8 to the load as a manual adjustment signal. In this way, by operating the display means and keyboard provided on the front panel 1 of the controller, the operator can easily perform the minimum necessary operating operations for the controller.

[0011] Prior to operation in such a normal control operation mode or manual operation, it is necessary to set various control parameters in the controller as described above. Displaying, setting, and changing such various parameters are performed by the external device 3, which is connected to the connection terminal 2 provided on the front panel 1. FIG. 2 is a diagram showing a parameter setting screen displayed on the screen by the parameter setting display means 31 of the external device 3 accessing the memory 6. On this screen, various parameters can be set to determine the functions of the controller. That is, in the input type field, specify that a K type thermocouple (chromel/alumel) is used as the temperature sensor, and in the output type field, specify that the output signal is a current output of 4 to 20 mA. Specified. Further, as the control type, here, PID control calculation is specified, and as the control direction, the direction of increase/decrease of the output signal corresponding to the positive/negative of the deviation signal is specified. For example, in the temperature control of the heating system, reverse operation is specified, and in the cooling system, normal operation is specified. Thereafter, the parameters of each item displayed here are specified in the same way as necessary. These specifications are made using a keyboard or the like provided on the external device. Here, the parameter loading means 32 stores (downloads) the various set parameters in the controller side memory 6 all at once by specifying "Register" on the soft key provided at the bottom of the screen. .

FIG. 3 is a diagram showing a control parameter setting screen. On this screen, all control parameters to be set are displayed as a list, and data can be specified and input into the corresponding item columns as necessary. In this item, auto-tuning is a function of calculating PID calculation parameters by oneself from response results and the like, and automatically setting them as parameter values of proportional band PB, integral time TI, and derivative time TD. In this item, "on" is specified if the auto-tuning function is used, and "off" is specified if it is not used. Each of these items shall be provided arbitrarily according to the functions provided in the controller. Proportional band PB, integral time TI, differential time T
For each item of D, the respective values are specified (set) in % for the proportional band, and in seconds for the integral time TI and differential time TD. Corresponding values are similarly specified for other items. On the right side of the screen, the process quantity PV and control output (operation signal output to the load) OUT are displayed as vertical bar graphs, and the value of the target set value SP is displayed as a triangle mark. The relationship is made so that it can be recognized in an analog way. There are several softkeys at the bottom of the screen. Here, when "registration" is specified, the control parameters specified in each item on the screen are stored (downloaded) in the controller side memory 6 all at once by the parameter loading means 32. Further, when "trend display" is specified among the soft keys, a trend graph is displayed as a window on a part of the screen by the trend graph display means 33.

FIG. 4 is a diagram showing a screen displayed by the trend graph display means 33 when "trend display" among the soft keys in FIG. 3 is designated. For example, a trend graph is displayed as a window in a part of the screen, and there are information such as process amount PV and target set value SP.
, control output OUT, etc. for a certain period of time in the past are read out from a database stored in the memory on the controller side and displayed. By referring to and checking these graphs, the control parameters can be set optimally. In addition, in order to display such a trend graph on the controller side, trend data is stored in a part of the memory 6 in advance, and this trend data can also be read from the external device 3 side. It is configured so that it can be done. Although the trend graph is displayed as a window in FIG. 4, it may be expanded to a screen that displays only the trend graph. On the screen displaying this trend graph, at the bottom of the screen there are designated keys such as "cycle" for changing the data collection cycle of the trend graph. Furthermore, by specifying the "control parameter" key, the window disappears and the screen returns to the original control parameter setting screen.

As described above, various parameters to be set in the controller can be set by connecting the external device 3 to the connection terminal provided on the front panel 1 of the controller, and by connecting the external device 3 to the parameter setting screen displayed on the screen of the external device. Using a keyboard or the like, you can easily set a large number of parameters as if you were operating a personal computer. After setting the parameters in this way, download each set parameter to the controller's memory, then disconnect the external device 3 and the controller, and perform normal control operation or manual operation with the controller alone. Can be done. Furthermore, various parameters once downloaded to the controller side can be read out, displayed, or changed by connecting the external device 3 to the controller again as needed. Note that the connection terminal 3 may be provided in a part of the keyboard. Furthermore, although it is assumed that a personal computer is used as the external device, it may also be an electronic notebook or a dedicated device that has a screen for setting and displaying parameters and data input means such as a keyboard or a mouse. Furthermore, if you use an external device with a data printing function or a data storage function, these setting data can be used for other controllers as well.

[0015]

[Effects of the Invention] As described above in detail, according to the present invention, the front panel or operation panel surface of the controller can have a simple configuration, allowing the operator to set various parameters. It is possible to provide a controller that is easy to operate and allows you to concentrate on driving without even thinking about it. Furthermore, although the front panel of the controller has a simple configuration, by connecting external devices, many parameters and functions can be easily set as if operating a personal computer.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram showing one embodiment of the present invention.

FIG. 2 is a diagram showing a parameter setting screen displayed on a screen functioning as a man-machine interface of an external device.

FIG. 3 is a diagram showing a control parameter setting screen.

FIG. 4 is a diagram showing a screen displayed when "trend display" is specified among the soft keys in FIG. 3;

[Explanation of symbols]

1 Front panel of the controller 10 Keyboard 11, 12 Display means 13 Up key 14 Down key 15 Set/Enter key 2 Connection terminal 3 External equipment 31 Parameter setting display means 32 Parameter loading means 33 Trend graph display means 4. Microprocessor 41 Display control means 42 Up/down counter 43 Keyboard interface 44 Control calculation means 46 Control parameter setting means 47 Set value output means 5 External device interface 6 Memory 7 A/D converter 8 Signal output means

Claims (2)

[Claims] Claim 1: A front panel is provided with a display means for digitally displaying a process quantity and a target set value, and control calculations are performed based on parameters stored in a memory on the deviation between the process quantity and the target set value, and the control output is output. In a digital indicating controller that outputs data to a process, the controller is provided with a connection terminal that connects to an external device having a man-machine interface function, and an interface that sends and receives data to and from the external device via this connection terminal, Parameter setting display means for displaying and changing settings of parameters related to control calculations by accessing a memory provided on the controller side in the external device via the connection terminal, and displaying the changed parameters in the memory. A digital indicating controller, characterized in that it is provided with parameter loading means for loading parameters into the controller. 2. The external device is provided with trend graph display means for displaying at least one of the process amount, control calculation output amount, and target set value as a trend graph according to specification. Digital indicating controller.