JP3100818B2 - Loop status display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current loop state (PV value / MV value / SV value / mode, etc.) in a plant control device, a pointer device, an analog display device such as an LED bar graph display device and the like. The present invention relates to a plant status display device to be displayed on a numeric display, and particularly to a PV value / M
This is a loop state display device capable of displaying a digital value of V value / SV value in engineering units such as a range different for each plant specification.

[0002]

2. Description of the Related Art At present, as a device for displaying a loop state of a plant, a device provided with an LED bar graph and a digital numeral display is mainly used.

[0003] Conventionally, a central control unit executing various controls is connected to a CRT operation device in which a plant operator monitors and operates the state of the plant, and control information is periodically transmitted to the CRT operation device.

[0004] A central control unit is provided with I / O cards (I / O cards for loops, digital input cards, digital output cards, etc.) for transmitting and receiving inputs and outputs of various plants, and input and output via dedicated I / O buses. Perform information exchange.

[0005] In some cases, the digital output card has a card form in which input and output are independent. A local loop status display device in such a plant control device is connected to a loop I / O via a dedicated communication bus.
Connected to O card.

The loop display device includes an LED bar graph representing the current state of the loop control amount, a mode change switch for changing the control mode, an SV (target value) in the M (manual) mode, and an MV (operation amount). ), A set value change key for changing the value of the value, a numeric display for digitally displaying the detailed value of the LED bar graph, and an LED.
It is composed of major elements such as a scale plate for displaying the LED bar graph display amount of the bar graph in the engineering unit (eg, kg / m ³ or the like) actually used.

[0007] In such a plan control system configuration, the following operation is performed.

In a normal plant operation, a central control unit takes in a PV (process variable) value collected from a loop I / O card via an I / O bus into a control calculation program, and sets an MV value so as to approach an SV value. Is calculated, and SV
The value and the control mode are transmitted to the loop I / O card via the I / O bus.

While the loop I / O card outputs the MV value received from the I / O bus, the SV I / O card has its own SV.
The data of the value, the MV value, the PV value, and the control mode are transmitted to the loop display device via the dedicated communication bus for the loop display device.

On the other hand, the loop display returns the current information to the loop I / O card.

This information is similarly reflected in the control operation of the central control unit via the I / O bus.

Further, the loop display device transmits the above data received from the loop I / O card to an LED bar graph,
Display on the mode input switch, A mode input switch, M mode input switch and numeric display.

Depending on the operating conditions of the plant, the setting of the operation mode, PV value, MV value and SV value may be locally changed from the loop display device without using the CRT operation device.

In such a case as well, the information is similarly transmitted to the central control unit via the loop I / O card and the I / O bus, taken into the control operation, displayed on the CRT operation unit, and notified to the operator. Have been.

[0015]

However, in the above plant control device, the PV sent from the central control device and the loop I / O card to the loop display device.
Since each data of the value, the MV value, and the SV value is in the% data format, each display of the loop display device is naturally also the% data.

In general, when the central control unit intends to transmit engineering unit data to the loop I / O card or the loop display device via the I / O bus as transmission text, the data format is such as% data. Since it is not an integer value but a floating data format,
There are problems such as a large increase in the data transmission amount, a large processing time for the floating operation of the loop I / O card and the loop display device, and a large increase in the total processing time.

In the loop display device which receives the PV value, the MV value and the SV value in the form of% data from the loop I / O card, the value displayed on the LED bar graph and the numerical display is naturally% data.

In addition, since the monitoring and determination of the plant condition by the normal operator cannot be performed by the% data, it is inconvenient to display the% data of the LED bar graph of the loop display device. This was addressed by attaching a scale plate seal printed with engineering units.

However, the scale plate seal is generally divided into 100 equal parts (one scale / 1%) or 50 equal parts (one scale / 2%).
It has a relatively rough scale configuration.

Therefore, the operator can judge the current value as an engineering unit together with the scale plate attached to the scale plate seal, but when trying to see the value with a finer resolution, it is necessary to refer to the numerical display together. Become.

However, since the numerical display can only display% data, the correlation between the data displayed in engineering units simply by the combination of the scale plate seal and the scale plate cannot be obtained, and the engineering unit data is displayed with fine resolution. Or, the problem that the setting cannot be changed occurs.

The present invention has been made in view of the above circumstances, and has as its object to provide a loop state display device capable of displaying engineering units of various data without changing the current system configuration and data transmission text specifications. And

[0023]

According to the present invention, there is provided a loop status display device comprising: a loop I / O card for inputting / outputting a plurality of signals to / from an I / O bus extending from a central control unit;
An analog display function that displays the current target value, process variable and manipulated variable on the O-card in an analog manner using an LED bar graph or pointer meter, a setting key that changes and sets the control mode and target value of the analog display function, and an analog display function digital numbers in the loop state display device comprising a digitally converts an analog display signal displayed numerical display for digitally displaying, on a digital numerical display of the numeric displays a combination operation of the setting key by
By displaying the character display, various records can be
And a range data setting function for setting the range data. Further, the loop state display device according to the present invention is characterized in that it has a holding function of storing the range data set by the range data setting function and holding the range data even when a power failure occurs.

[0024]

In the loop state display device of the present invention, a plurality of signals are input / output to / from the I / O bus extending from the central processing control by using a loop I / O card, and the current target is supplied to the loop I / O card. Analog display of values, process values and manuscript values with LED bar graphs or pointer meters,
Change and set the control mode and target value of the analog display function, convert the analog display signal displayed by the analog display function to digital, and display it digitally. Is displayed. Further, the loop state display device according to the second aspect is characterized in that the range data set by the range data setting function is stored and retained even when a power failure occurs.

[0025]

Next, an embodiment of the loop state display device of the present invention will be described. 1 to 3, reference numerals 5 and 6 denote loop I / O cards for inputting and outputting a plurality of signals to an I / O bus 2 extending from the central control unit 3, and reference numeral 17 denotes a loop I / O card 5, 6. Analog display function for displaying the target value (hereinafter, referred to as SV), process variable (hereinafter, referred to as PV) value and manipulated variable (hereinafter, referred to as MV) value on an LED bar graph or a pointer meter. A setting key 16 for changing and setting the control mode and target value of the function 17, a numeral 16 is a numeric display for digitally converting an analog display signal displayed by the analog display function 17, and a digital display 20 is a combination of the setting keys 11 to 13. This is a range data setting function for displaying the digital numerical display of the numerical display 16 in engineering units by the device, and is an I / O bus extending from the central control unit 3. In the plant control system consists of I / O cards for executing a plurality of input and output 4, the current SV value to the loop for I / O cards 5, P
It has a function to display V value and MV value in analog with LED bar graph or pointer meter, a mode key to change and set the control mode, and a key to manually change SV value and MV value. In a loop state display device having a numerical display 16 for digitally displaying the numerical data, range data RH (upper limit range) / RL () for displaying the digital numerical display of the numerical display 16 in engineering units by a combination of keys. A loop state display device having a function of setting a lower limit range, and having a means for holding the set range data even during a power failure.

That is, the loop state display device of the present embodiment has means for enabling the setting of the upper limit range RH and the lower limit range RL of the engineering unit by a combination of the operations of various key switches 11 to 15 on the existing front panel. Means for storing and holding the value of RH / RL even during a power failure.

Therefore, the loop state display device of the present embodiment recognizes the RH / RL set by the operator and displays the engineering unit data on the numerical display according to the range by the internal firmware calculation.

Further, since the set RH / RL range data is retained even in the event of a power failure by the internal storage means, the engineering unit data can be reliably displayed even in the event of a double power failure.

Even if the range needs to be changed due to a change in the plant operation plan or the like, the range can be easily changed.

FIG. 3 is an explanatory diagram showing the configuration of the loop state display device according to one embodiment of the present invention.

This loop state display device has a loop I / O
Communication interface 2 for data transmission with O card 5
6. Microprocessor 1 for executing various programs
9. RO connected to microprocessor control bus 20
M21, RAM22, display panel switch 24, E ² P
It comprises a ROM 23 and a power supply unit 25.

The E ² PROM 23 may be implemented by a combination of a general static RAM and a battery.

FIG. 4 shows an example of setting the RH / RL range in this embodiment.

The setting of the RH / RL range is merely an example, and the key device is not necessarily limited to this example.

In the range setting mode, the mode switch (M mode switch) M and the key 40 are simultaneously pressed (RH) to set the range display mode. Next, by pressing SV ↑, the RL range is displayed. (The display of RH / RL is distinguished by the point display of the SV indication LED bar graph.) Pressing SV ↓ during RH / RL display switches to the parameter change mode. (The display / setting can be canceled by pressing the key 40. In the parameter change mode, the numeric item display LED lights in red.) Here, the RH display shows the RH value on the numeric display, and the SV indication LED bar graph 75% of the points are displayed.

In the RL display, the RL value is displayed on the numeric display, and points corresponding to 25% are displayed on the SV indication LED bar graph.

Next, in the range display mode, the normal display mode is a mode in which PV / SV / MV is selected and displayed by operating the keys 40.

After the power supply of the ULDU 12 is turned on, this mode is set. And the numerical display is EU / EU /%
The SV indicator LED bar graph displays the SV value, and the numeric item display LEDs correspond to red /
Green / off.

The RH display mode is switched to the RH display mode by simultaneously pressing the key M and the key 40 in the normal display mode, and the current value of RH is displayed on the numeric display by the SV instruction LE.
A point display equivalent to 75% is displayed on the D bar graph, and when the display is switched from the RH display mode to the RL display mode, the display is switched by pressing SV ↑. When the display is switched from the RH display mode to the normal display mode, the key 40 is pressed. Switch.

In the RL display mode, the current value of the RL is displayed on the numeric display as a point corresponding to 25% on the SV indicator LED bar graph, and when switching from the RL display mode to the RH display mode, the SV ↑ is turned off. When switching from the RL display mode to the normal display mode, the key 40 is pressed to switch the mode.

Next, in the range setting / change mode,
From the range display mode to the range setting / change mode, R
H. Press SV ↓ in the RL display mode. (The parameter (range information) to be displayed becomes the mode that can be set and changed. When the change mode is entered, the zero display that was not displayed is redisplayed. The leftmost digit flashes, and SV
The indication LED bar craft keeps displaying the point (value corresponding to RH / RL) which has been displayed so far, and the numeric item display LED lights up in red.

To change the data in the range setting / change mode, press SV ↓ to change the data of the blinking digit of the numeric display, and the number displayed every time SV ↓ is pressed changes to [0 → 1 → 2 →... → 9 → 0], and when the leftmost digit is blinking, it changes as [0 → 1 → 2 →... 9 → − → 0].

In the range setting / change mode, the blinking digit of the numeric display can be moved by pressing SV に て in the range setting / change mode, and the blinking digit moves one digit to the right. When SV ↑ is pressed while the rightmost digit of the numeric display is flashing, the decimal point flashes, the rightmost digit that was flashing until then lights up, and the decimal point of the numeric display flashes. When SV ↑ is pressed while the display is on, the blinking of the decimal point turns on, and when the blinking of the decimal point stops, the numerical item display LED turns green while waiting for a write confirmation.

To change the decimal point position, if SV ↓ is pressed while the decimal point is blinking, the decimal point position moves to the right one digit at a time, and if SV ↓ is pressed while the right end is lit, the decimal point is changed. Move to the leftmost digit and blink.

In the confirmation waiting state, when SV # is pressed while the decimal point is blinking, the blinking stops and the confirmation waiting state is reached (in this state, the numeric item display LED changes from red to green).
The displayed numeric pattern remains set, and confirmation and writing can be performed by pressing the key 40 here.
(If you want to stop writing, press any other key to stop writing.) To confirm or write the range setting / change mode, press the key 40 when the decimal point stops blinking. The displayed number pattern and decimal point position are written. (Number item display L
The green light of the ED becomes red light. ) The display of the numeric display returns to the display of the changed RH or RL, and the upper digit zero is not displayed (zero suppression). (The minus sign moves to the right digit accordingly.) To cancel the range change mode, press the key 40 while the numbers and decimal point are blinking. When it stops, the (LE
Pressing a key other than the key 40 (when D is lit green) cancels the change and returns to the range change mode.

In the loop state display device according to the second aspect, reference numeral 23 denotes a holding function for storing the range data set by the range data setting function 20 and holding the range data even when a power failure occurs.

[0047]

According to the present invention, the range can be easily set by a combination operation of the existing setting keys without providing a special key for setting the special range data, and the numerical display of the loop status display is engineered. Since the unit data can be displayed, the SV and MV setting values can be changed based on the analog data display using the conventional LED bar graph. Since the value can be easily set, controllability and operability are significantly improved.

The engineering unit data display of the loop status display can be realized at a local level without imposing a load on the operation of the host system.

Further, since the range data is retained without being lost even in the event of a power failure, there is no need to reset it after the power is restored, and the convenience for the operator is improved.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a loop state display device showing one embodiment of the present invention.

FIG. 2 is a front view of FIG.

FIG. 3 is an explanatory diagram of a soft sequence shown in FIG. 1;

FIG. 4 is an explanatory diagram showing handling of FIG. 1;

FIG. 5 is an explanatory diagram of the flowchart in FIG. 1;

[Explanation of symbols]

 5, 6 Loop I / O card 11 to 13 key 16 Numeric display 17 Analog display function 20 Range data setting function

Claims (2)

(57) [Claims] 1. A loop I / O card for inputting / outputting a plurality of signals to / from an I / O bus extending from a central controller, and a current target value, a process value, and a manuscript value are stored in the loop I / O card. An analog display function for displaying an analog signal with an LED bar graph or a pointer meter, a setting key for changing and setting a control mode and a target value of the analog display function, and converting an analog display signal displayed by the analog display function into a digital signal. In a loop state display device comprising a digital display for digital display, it is necessary to display a digital numerical display on the numerical display by a combination operation of the setting keys.
A loop state display device having a range data setting function for setting various range data in various engineering units . 2. The loop state display device according to claim 1, further comprising a holding function of storing the range data set by the range data setting function and holding the range data even in the event of a power failure.