basic automation
Automation or industrial automaton is the use of computers to control industrial machinery and processes, replacing human operators. It's step beyond mechanizaton, where human operators are provided with machinery to help them in their job. Some advantages of using automation in industrial are repeatibility, tighter quality control, wasted reduction, integrated with business system, increased productivity and of course reduction of labor. On contrary, some disadvantages are high initial costs and increased dependence and maintenance.
By the middle of the 20th century, automation had existed for many years on a small scale, using mechanical devices to automate the production of a simply shaped items. However the concepts only become truly practical with the addition of the computer, which flexibility allowed it to drive almost any sor of task. Computers with the required combination pf power, price, and size first started to appear in the 1960s., and since then have taken over the vast majority of assembly line tasks.
Another form of automation that involves computers in industrial scale is called control system, where computers are programmed to make easy operators in handling by interfacing with HMI ( human machine interface ).
DCS ( Distributed Control System )
DCS is a part of manufacturing system. It is generallty digitally, and normallly consist of field instrument,connected via wiring or buses, analog or digital and finally stream to HMI or control consoles.
DCS is used in industrial and applications to monitor and controlled equipment with remote human intervention. DCS is a very broad umbrella that describes solution across large victory of industries, including :
- electrical power distribution
- enviromental control system
- water management
- refining
- manufacturing ( pulp and paper, polymer, oil and gas,etc )
Control System Concept
A control system is a group of electronic or mechanical devices connected together in an effort to predict and control the behaviour of process. A process can be defined as a method of effecting changes in the properties of some physical objects.
A control system consist of the number of independent devices, each serving particular purpose within the system. Some of these devices are linked together to predict and control individual steps in the process.
1.1 Control Loop
a control loop is a group of devices the collective tasks of which is to perform the prediction and control of a very specific steps in the process. It's fundamentally designed to control only one physical aspect of the process. This physical aspect,since it's capable of change, is called the procrss variable. The control loop is designed so that the primary element or measurement is installed at some point to the process where any changed made to the process variable can be readily monitored are evaluated. If we link the primary element to the final control element through controller then we hava created a controlling loop.
1.1.1 Primary Element
Primary elements are the measuring components of any control loop. The entire purpose of these components is to observe the quality or quantity of a process variable and translate it to a signal that is meaningful to the operator and/or to the controller. A primary elements is either a tranduser or a transmitter. If it's a tranduser then it must be coupled to a transmitter to allow it to communicate within the control loop. Transmitter allow the sensed value to be sent over relatively long distance without serious degradation of the signal.
Trandusers are generally defined as a device, which will convert one type of energy into another. Such as the orifice plate which convert kinetic energy ( flow velocity ) into a potential energy ( differential pressure ). Similarly thermocouple converts temperature differential into electric voltage.
Transmitter are defined as trandusers that include a pneumatic or electronic amplifier capable of producting one of the standard transmission signal used in control loops.
1.1.2 Controllers
Controllers are the brains of any control loop. The task of this device is to receive the signal transmitted from the prymary element, compare it to the value decided by the operator, determine if any changes need to be made the process variable and implement those changes.
Any devices can be considered a controllers if is processes theree fundamental characteristic :
- Process Variable
This is necessary to allow the controller the asses the value of the process and determine the degree of change the process is experiencing.
- Set point
This is the value that is generated by an operator or some other device that informs to the controller as to the value that is desired for the processs being controlled. the controller will attempt to maintain the process variable at this set point.
- Output
This is a signal that is used to manipulate final element such as control valve or pump in an effort to changed the measured value of the process variable.
1.1.3 Final Control Element
The most common final control element is the control valve. This is a mechanical devices designed to modulate the process loss across itself through the use of variable sized opening. the valve is usually attached to an actuator that is pneumatically, hydraulically or electrically driven. The function of actuator is to provide linear or rotary motion to valve body, thereby causing the valve opening vary. Some valves have velve positioners installed. these devices are mini controllers in themselves, the purpose is to guarantee the position of valve in relation to the signal. valve positioners have linear response to the incoming signal as the most common characteristic. Most positioners, however, are capable of being field configured and calibrated to provide various signal to motion responses.
By the middle of the 20th century, automation had existed for many years on a small scale, using mechanical devices to automate the production of a simply shaped items. However the concepts only become truly practical with the addition of the computer, which flexibility allowed it to drive almost any sor of task. Computers with the required combination pf power, price, and size first started to appear in the 1960s., and since then have taken over the vast majority of assembly line tasks.
Another form of automation that involves computers in industrial scale is called control system, where computers are programmed to make easy operators in handling by interfacing with HMI ( human machine interface ).
DCS ( Distributed Control System )
DCS is a part of manufacturing system. It is generallty digitally, and normallly consist of field instrument,connected via wiring or buses, analog or digital and finally stream to HMI or control consoles.
DCS is used in industrial and applications to monitor and controlled equipment with remote human intervention. DCS is a very broad umbrella that describes solution across large victory of industries, including :
- electrical power distribution
- enviromental control system
- water management
- refining
- manufacturing ( pulp and paper, polymer, oil and gas,etc )
Control System Concept
A control system is a group of electronic or mechanical devices connected together in an effort to predict and control the behaviour of process. A process can be defined as a method of effecting changes in the properties of some physical objects.
A control system consist of the number of independent devices, each serving particular purpose within the system. Some of these devices are linked together to predict and control individual steps in the process.
1.1 Control Loop
a control loop is a group of devices the collective tasks of which is to perform the prediction and control of a very specific steps in the process. It's fundamentally designed to control only one physical aspect of the process. This physical aspect,since it's capable of change, is called the procrss variable. The control loop is designed so that the primary element or measurement is installed at some point to the process where any changed made to the process variable can be readily monitored are evaluated. If we link the primary element to the final control element through controller then we hava created a controlling loop.
1.1.1 Primary Element
Primary elements are the measuring components of any control loop. The entire purpose of these components is to observe the quality or quantity of a process variable and translate it to a signal that is meaningful to the operator and/or to the controller. A primary elements is either a tranduser or a transmitter. If it's a tranduser then it must be coupled to a transmitter to allow it to communicate within the control loop. Transmitter allow the sensed value to be sent over relatively long distance without serious degradation of the signal.
Trandusers are generally defined as a device, which will convert one type of energy into another. Such as the orifice plate which convert kinetic energy ( flow velocity ) into a potential energy ( differential pressure ). Similarly thermocouple converts temperature differential into electric voltage.
Transmitter are defined as trandusers that include a pneumatic or electronic amplifier capable of producting one of the standard transmission signal used in control loops.
1.1.2 Controllers
Controllers are the brains of any control loop. The task of this device is to receive the signal transmitted from the prymary element, compare it to the value decided by the operator, determine if any changes need to be made the process variable and implement those changes.
Any devices can be considered a controllers if is processes theree fundamental characteristic :
- Process Variable
This is necessary to allow the controller the asses the value of the process and determine the degree of change the process is experiencing.
- Set point
This is the value that is generated by an operator or some other device that informs to the controller as to the value that is desired for the processs being controlled. the controller will attempt to maintain the process variable at this set point.
- Output
This is a signal that is used to manipulate final element such as control valve or pump in an effort to changed the measured value of the process variable.
1.1.3 Final Control Element
The most common final control element is the control valve. This is a mechanical devices designed to modulate the process loss across itself through the use of variable sized opening. the valve is usually attached to an actuator that is pneumatically, hydraulically or electrically driven. The function of actuator is to provide linear or rotary motion to valve body, thereby causing the valve opening vary. Some valves have velve positioners installed. these devices are mini controllers in themselves, the purpose is to guarantee the position of valve in relation to the signal. valve positioners have linear response to the incoming signal as the most common characteristic. Most positioners, however, are capable of being field configured and calibrated to provide various signal to motion responses.
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