JPH06284477A - Controller - Google Patents

Abstract

PURPOSE:To enable a monitoring and an operation also at an abnormal time by providing a backup gateway forming the communication route between upper and lower rank communication buses by receiving the abnormal signal from a field control station. CONSTITUTION:When the abnormal signal from the fault signal input/output interface 24 of a field control station (FCS) 2 is received by the fault signal input/output interface 34 of a backup gateway 3, a self-diagnois means 33 detects the signal. A communication data processing means 32 converts the digital signal on a lower rank communication bus into a protocol and transmits it to an upper communication bus 4. By the same way, the means 32 performs the signal conversion for the operation signal from an operator monitoring console 1, transmits the signal to a lower rank communication bus and forms a communication route between an upper rank communication bus 4 and a lower rank communication bus. Therefore, the signal from a field equipment is directly transmitted to the console by bypassing an FCS. Thus, also when the FCS is abnormal, the monitoring and operation of a plant can be performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an instrumentation control device having an operator monitoring console, and particularly to a field control station or a programmable logic controller using a microprocessor, and a transmitter or an operating terminal installed in a plant. The present invention relates to a device equipped with a lower communication bus interface for transmitting a signal to and from a field device such as.

[0002]

2. Description of the Related Art Conventionally, a control device has been put into practical use in which a field control station or a programmable logic controller is directly connected to a transmitter or an operating end for monitoring or operation. In this case, if the field control station, the programmable logic controller, etc. stop abnormally, both the transmitter and the operating end will stop. FIG. 5 is a conceptual diagram of the configuration of the control device. The operator monitoring console 1 and the field control station 2 or the programmable logic controller 10 are connected to a host communication bus 4 (control or general-purpose LAN).
Connect through. The field control station 2 or the programmable logic controller 10 is connected to a transmitter 7 or an operating end 9 installed in a field of a plant or the like via a lower communication bus 5. From the operator monitoring console 1, the operator can move the transmitter 7 and the operating terminal 9
Monitor and operate the plant via. Even with such a configuration, if an abnormality occurs in the field control station 2, the programmable logic controller 10, or the like, there is a drawback that the plant operation cannot be continued. Therefore, the field control station 2
Has a dual CPU and has a redundant design for each part to improve reliability.

[0003]

In the control device having the above-mentioned structure, when one of the field control stations of the redundant structure is abnormally stopped, the other is backed up to control it via the lower communication bus 5. It is possible to continue the operation of the transmitter 7 and operating end 9 connected to the equipment, but if both of the redundant field control stations become abnormal, operation and monitoring of the plant will be completely impossible. Become. The object of the present invention is to pay attention to this point, and when the field control station 2 or the like is abnormally stopped, the plant is directly operated from the host operator monitoring console 1 without passing through the field control station 2 or the like. In order to continue the monitoring and operation of the upper communication bus 5, a digital signal on the lower communication bus 5 is appropriately converted and a bypass path, that is, a backup gateway for transmitting the digital signal to the upper communication bus 4 is provided.

[0004]

According to the present invention, an operator monitoring console and a field control station or the like are connected by an upper communication bus, and the field control station or the like and a transmitter or an operation installed in a plant are connected. A control device in which devices such as terminals are connected by a lower communication bus has a protocol conversion function between the upper communication bus and the lower communication bus, and when a signal indicating an abnormality is received from this field control station, etc. Provide a backup gateway configured to form a communication path between the upper communication bus and the lower communication bus.

[0005]

With the above configuration, the backup gateway, which has received an abnormal stop signal from the field control station or the like, receives the digital signal on the lower communication bus,
Convert the protocol and send it to the upper communication bus. Similarly, the backup gateway similarly converts the operation signal from the operator monitoring console and sends it to the lower communication bus. Therefore, the signal from the field device is
Since it bypasses the control station and is directly connected to the operator monitoring console, the plant can be monitored and operated even if the field control station is abnormal.

[0006]

The present invention will be described below with reference to the drawings. Figure 1,
FIG. 2 is a configuration block diagram showing an embodiment of the present invention. In these figures, parts corresponding to those in FIG. 5 are designated by the same reference numerals. The device of the present invention has a structural feature in that a backup gateway is added to the conceptual diagram of the structure of the control device shown in FIG. Next, the function and operation of each device will be described. First, referring to FIG. 1, reference numeral 1 denotes an operator monitoring console (hereinafter referred to as O
It is called PS1) and performs various displays and operations necessary for operating the control device. In addition, various peripheral devices and field control station 2 are connected by host communication bus 4.
(Hereinafter referred to as FCS2) and backup gateway 3. Since the upper communication bus 4 performs high speed communication, a coaxial cable is used as appropriate.

In OPS1, the display control means 11 is
On the screen of the display means (CRT) 12, a screen required for monitoring or operation normally via the FCS 2 is displayed. FCS
When 2 is abnormal, a screen required for monitoring and operation via the backup gateway 3 is displayed. The FCS control means 13 manages the control operation normally performed by the FCS 2. However, when the FCS 2 detects that the FCS 2 is abnormal, its function carries out the processing at the time of abnormality and the backup gateway control means 14 takes over the control management.

Backup gateway control means 14
Manages the operation of the backup gateway 3 when the FCS2 is abnormal, and enables the OPS1 to transmit and receive measurement signals and control signals to and from the transmitter 7, the operating end 9, and the like. The operating means 15 performs commands and data operations to the peripheral device, FCS 2, backup gateway 3, transmitter 7, operating end 9 and the like by means of a keyboard, pointing device and the like. The self-diagnosis means 17 detects a program abnormality, a hardware abnormality, a power supply abnormality, etc., and displays according to the abnormality level. The communication interface 18 has an interface function of performing communication with the FCS 2 and the backup gateway 3 via the upper communication bus 4.

In the field control station 2 (FCS2), the upper communication interface 21
Is connected to the upper communication bus 4, and the measurement control means 22 performs monitoring of measurement signals, alarms, feedback control calculation such as PID, and logical calculation of sequence control, and generates a control signal. The self-diagnosis means 23 is
An abnormality signal is output from the failure signal input / output interface 24 by detecting a hardware abnormality, a power supply abnormality, or the like. The lower-order communication interface 25 is connected to the lower-order communication bus (field bus) 5 and exchanges measurement signals and control signals with the transmitter 7 and the operating end 9.

The backup gateway 3 is a device that physically and logically matches the signals so that signals can be transferred between the upper communication bus 4 and the lower communication bus 5.
This communication protocol is a protocol. The upper communication interface 31 connects to the upper communication bus 4. The communication data processing means 32 mutually converts the protocol for transmitting the signal of the lower communication bus 5 to the upper communication bus 4 or in the reverse direction. In addition, it has functions such as signal path change and data buffering. Self-diagnosis means 3
3 detects a program error, a hardware error, a power supply error, etc. The failure signal input / output interface 34 is FC
When an abnormal signal is input from the failure signal input / output interface 24 in S2, a communication path changing process is performed to form a communication path between the upper communication bus 4 and the lower communication bus 5. The lower-layer communication interface 35 is connected to the lower-layer communication bus 5 and exchanges a measurement signal and a control signal with the transmitter 7, the operation terminal 9 and the like.

Referring to FIG. 2, a lower communication bus (field bus) 5 is a transmitter 7 or an operating terminal 9 installed in a plant.
It is a signal wiring that connects a field device such as the FCS 2 and the backup gateway 3 to each other, and superimposes a digital signal and a DC power supply as necessary. If the speed is low, use twisted wires, etc. as appropriate. Reference numeral 6 denotes a detection sensor section. Pressure, position, temperature, flow rate, etc. are detected by the respective detection sensors and transmitted to the detection amount conversion means 73.

The transmitter 7 is connected to the lower communication bus 5 by a communication interface 71. Data storage means 72
Is the detection end number, detection conversion data, detector measurement span,
Stores constant data such as parameter settings. The detection amount conversion means 73 converts a signal from the detection sensor unit 6, for example, a thermocouple electric signal or the like so as to match a predetermined protocol. The self-diagnosis unit 74 detects an abnormality in each unit including the detection sensor unit 6. The various measurement signals and control signals described above are transmitted via the communication interface 71 and the lower communication bus 5 to the FCS 2 or backup.
Exchanged with Gateway 3. The driving power is supplied by being superposed on the lower communication bus 5, or supplied from a separately provided power terminal.

The operation terminal 9 is connected to the lower communication bus 5 by a communication interface 91, and performs predetermined signal conversion of data such as opening signal, measurement span change, parameter setting / change, and self-diagnosis result. And sends it to the internal circuit after inversely converting various data and control signals on the lower communication bus 5. The data storage unit 92 stores an operation end number, an operation signal value, an operation range, unique characteristic data, and the like. The control signal / power conversion means 93 operates the OPS 1 or responds to the increase / decrease of the operation signal sent from the FCS 2 to the lower communication bus 5. The forward or reverse rotation of the motor is applied to operate the valve opening. The opening value is detected by a detection sensor unit attached to the valve element, and is sent out onto the lower communication bus 5 via the valve opening value converting means 94 and the communication interface 91. The self-diagnosis means 95 detects an abnormality in each part including the valve body 8. The DC power source for driving the operating end 9 is the same as that for the detecting end 7. In addition to this, compressed air AS or electric power PS is supplied as power for driving the valve body 8.

According to the flow charts of FIGS. 3 and 4, F
The switching operation when there is an abnormality in CS2 will be described. During normal operation, the data on the upper communication bus 4 and the lower communication bus 5 are always taken into the data area provided on the data buffer memory of the backup gateway 3 at regular intervals. This includes the transmitter number from the transmitter, various data, valve opening data, valve operation data with the valve number from OPS1, and the like. 1) The OPS 1 detects that an abnormality has occurred in the FCS 2 through the upper communication bus 4. 2) The OPS 1 activates the abnormality processing program and performs the following processing. The signal from the FCS 2 is disconnected from the upper communication bus 4. Start the backup gateway control means. Request activation and communication to the backup gateway 3.

3) Backup Gateway 3 is F
The FCS2 is judged to be abnormal from the signal output from the alarm input / output interface of CS2. 4) Backup Gateway 3 starts the program at the time of abnormality and performs the following processing. The data in the data buffer table is converted and output to the upper communication bus 4. The operation signal data on the upper communication bus 4 is converted and stored in the data buffer table. The previous operation signal data is compared with the new data, and if there is a change, it is output to the lower communication bus 5. In this way, the detecting end 7 and the operating end 9 are directly monitored and operated from the OPS 1 until the FCS 2 is restored.

In the above description using FIGS. 3 and 4, F
When CS2 is abnormal, OPS1 starts the abnormality processing program first, and then the backup gateway, but the order is not limited to this.
The backup gateway that receives the abnormal signal from S2 may be in the operation sequence of immediately forming a signal path between the upper communication bus and the lower communication bus. The function of the backup gateway may be accommodated in the FCS2 or PLC cubicle.

[0017]

According to the present invention, by providing the backup gateway 3, it is possible to monitor and operate the field equipment from the upper OPS 1 even when the FCS 2 or PLC or the like stops abnormally. Since the operation can be performed more reliably, a great effect can be expected in ensuring safety in an emergency.

[Brief description of drawings]

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

FIG. 2 is a diagram subsequent to FIG. Indicates the field device side.

FIG. 3 is a flowchart showing an operation.

FIG. 4 is a diagram following FIG. 3; Shows the backup gateway side.

FIG. 5 is a conceptual diagram of a configuration of a conventional control device.

[Explanation of symbols]

1 Operator monitoring console 2 Field control station 3 Backup gateway 4 Upper communication bus 5 Lower communication bus 6 Detection sensor section 7 Transmitter 8 Valve body 9 Operating end 11 Display control means 12 Display means (CRT) 13 FCS control means 14 Backup gateway Control means 15 Operation means 16 Keyboard etc. 17,23,33,74,94 Self-diagnosis means 18,21,31,25,35,71,91 Communication interface 22 Measurement control means 24,34 Fault signal input / output interface 32 Communication data Processing means 72, 92 Data storage means 73 Detection amount conversion means 93 Control signal / power conversion means 95 Valve opening value detection conversion means IF interface PS Power source AS Power pressurized air

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location H04L 12/40 29/14

Claims (1)

[Claims] 1. An operator monitoring console and a field control station are connected by a host communication bus,
In the control device in which the field control station and the field devices such as transmitters and operating terminals installed in the plant are connected by the lower communication bus, the function of protocol conversion between the upper communication bus and the lower communication bus is provided. When the field control station is abnormal, a backup gateway is provided to form a communication path between the upper communication bus and the lower communication bus in response to a signal indicating an abnormality from the field control station. A control device which enables monitoring and operation of a field device from an operator monitoring console through the backup gateway.