JP2002006941A - Process control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a process control system which can make a cable laying unnecessary, reduce an associated large amount of manpower and costs and easily construct the system. SOLUTION: A signal communication between a sensor 1 and a controller 2 and the signal communication between the controller 2 and an actuator 3 are configured to be processed with a wireless LAN.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a process control system.

[0002]

2. Description of the Related Art Generally, in various plants and the like, a process control system that operates an actuator such as a valve by a control signal output from a controller based on a detection signal such as a temperature and a pressure detected by a sensor is used. I have.

FIG. 2 shows an example of a conventional process control system, in which 1 is a sensor, 2 is a controller, 3 is an actuator, and the sensor 1 and the controller 2 are connected by a cable 4 and a controller. The actuator 2 and the actuator 3 are connected by a cable 5. During operation of a plant or the like, a temperature, a pressure, and the like are detected by the sensor 1, and a detection signal is sent to the controller 2 via the cable 4. The degree to which the valve opening and the like should be adjusted is calculated based on the detection signal from 1 and a control signal based on the calculation result is output to the actuator 3 via the cable 5 so that the actuator 3 operates. It has become.

At the same time, various request signals from the controller 2 to the sensor 1 are sent via a cable 4, and feedback signals and the like from the actuator 3 to the controller 2 are sent via a cable 5.

[0005]

However, in the conventional process control system as described above, especially in the case of a chemical plant or the like constructed on a vast land, the cables 4 and 5 become very long, and the cables for laying the cables are extremely long. Man-hours and costs increase,
In addition, it is difficult to lay the cables 4 and 5 even when the sensor 1 and the actuator 3 are newly added.

SUMMARY OF THE INVENTION In view of the above circumstances, the present invention can obviate the need for cable laying, can reduce a large number of man-hours and costs required thereby, and can easily construct a system. It is intended to provide a control system.

[0007]

SUMMARY OF THE INVENTION The present invention is a process control system for operating an actuator by a control signal output from a controller based on a detection signal detected by a sensor, wherein the signal between the sensor and the controller is provided. The present invention relates to a process control system characterized in that transmission / reception and signal transmission / reception between a controller and an actuator are performed by a wireless LAN.

The present invention also relates to a process control system for operating an actuator by a control signal output from a controller based on a detection signal detected by a sensor, comprising: a sensor having a wireless LAN interface; And a controller provided with a wireless LAN interface and an actuator provided with a wireless LAN interface.

According to the above means, the following effects can be obtained.

During operation of a plant or the like, a detection signal detected by a sensor is transmitted to a controller via a wireless LAN, and the controller performs an operation for controlling an actuator based on the detection signal from the sensor. Is output from the controller to the actuator via the wireless LAN, and the actuator operates.

At the same time, transmission and reception of various request signals from the controller to the sensor and transmission and reception of feedback signals from the actuator to the controller are performed by wireless LAN.

As a result, even in a chemical plant or the like constructed on a vast land, it is not necessary to lay a very long cable, so that the man-hour and cost for the laying are not required, and a new sensor or actuator is required. It is also easy to add

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an example of an embodiment of the present invention. In the figure, the portions denoted by the same reference numerals as those in FIG. 2 represent the same components, and the basic configuration is the same as that of the conventional device shown in FIG. As shown in FIG. 1, the feature of the illustrated example is that signals are transmitted and received between the sensor 1 and the controller 2.
In addition, signals are exchanged between the controller 2 and the actuator 3 via a wireless LAN.

The sensor 1 is provided with a wireless LAN interface 6, the controller 2 is provided with a wireless LAN interface 7, and the actuator 3 is provided with a wireless LAN interface 8.

Next, the operation of the illustrated example will be described.

During operation of a plant or the like, detection signals such as temperature and pressure detected by the sensor 1 are received by the wireless LAN interface 7 connected to the controller 2 from the wireless LAN interface 6 connected to the sensor 1, The controller 2 calculates how much the valve opening or the like should be adjusted based on the detection signal from the sensor 1 in the controller 2, and a control signal based on the calculation result is transmitted to the wireless LA connected to the controller 2.
The data is received from the N interface 7 by the wireless LAN interface 8 connected to the actuator 3 and output to the actuator 3 so that the actuator 3 operates.

At the same time, transmission and reception of various request signals from the controller 2 to the sensor 1 and transmission and reception of feedback signals from the actuator 3 to the controller 2 are also performed between the wireless LAN interfaces 7 and 6 and between the wireless LAN interfaces 8 and 7. It takes shape.

As a result, even in a chemical plant or the like constructed on a vast land, it is not necessary to lay very long cables 4 and 5, so that the man-hour and cost for the laying are not required, and the sensor 1 is not required. It is also easy to add a new actuator or actuator 3.

In this way, the laying of the cables 4 and 5 can be made unnecessary, and the enormous man-hours and costs required accordingly can be reduced, and the system can be easily constructed.

It should be noted that the process control system of the present invention is not limited to the illustrated example described above, and it is needless to say that various changes can be made without departing from the gist of the present invention.

[0022]

As described above, according to the process control system of the present invention, it is not necessary to lay cables.
Accordingly, a great number of man-hours and costs required can be reduced, and an excellent effect that the system can be easily constructed can be obtained.

[Brief description of the drawings]

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

FIG. 2 is a schematic configuration diagram of a conventional example.

[Explanation of symbols]

 1 Sensor 2 Controller 3 Actuator 6 Wireless LAN Interface 7 Wireless LAN Interface 8 Wireless LAN Interface

Claims (2)

[Claims] 1. A process control system for operating an actuator in accordance with a control signal output from a controller based on a detection signal detected by a sensor, wherein the process control system transmits and receives a signal between the sensor and the controller, and transmits and receives signals between the controller and the actuator. Signal exchange between wireless LAN
A process control system characterized in that the process is performed by: 2. A process control system for operating an actuator according to a control signal output from a controller based on a detection signal detected by a sensor, comprising: a sensor provided with a wireless LAN interface;
N controller and wireless LAN
A process control system comprising: an actuator provided with an interface.