Listed the best PLC training institute centers in Coimbatore which are
ranked the top most in the PLC training sector of India. Reach out to
the PLC training center using the information provided.PLC training
in Coimbatore is popular among the students in a great deal which can be
understood clearly if you see the placement records of these institutes.
Sunday, November 9, 2014
Friday, July 18, 2014
Best PLC Training Institutes in Bangalore
Listed the best PLC training institute centers in Bangalore which are
ranked the top most in the PLC training sector of India. Reach out to
the PLC training center using the information provided.PLC training
in Bangalore is popular among the students in a great deal which can be
understood clearly if you see the placement records of these institutes
Saturday, July 12, 2014
Best PLC Training Institutes in Mumbai
Listed the best PLC training institute centers in Mumbai which are
ranked the top most in the PLC training sector of India. Reach out to
the PLC training center using the information provided.PLC training in Mumbai is popular among the students in a great deal which can be
understood clearly if you see the placement records of these institutes
Saturday, June 14, 2014
Best PLC Training Institutes in Kolkata
Listed the best PLC training institute centers in Kolkata which are
ranked the top most in the PLC training sector of India. Reach out to
the PLC training center using the information provided.PLC training in
Kolkata is popular among the students in a great deal which can be
understood clearly if you see the placement records of these institutes
Wednesday, June 4, 2014
Best PLC Training Institutes in Hyderabad
Listed the best PLC training institute centers in Hyderabad which are
ranked the top most in the PLC training sector of India. Reach out to
the PLC training center using the information provided.PLC training in Hyderabad is popular among the students in a great deal which can be
understood clearly if you see the placement records of these institutes
Monday, June 2, 2014
Best PLC Training Institutes in Delhi
Listed the best PLC training institute centers in delhi which are
ranked the top most in the PLC training sector of India. Reach out to
the PLC training center using the information provided.PLC training in delhi is popular among the students in a great deal which can be
understood clearly if you see the placement records of these institutes
Tuesday, May 27, 2014
Best PLC Training Institutes in Noida
Listed the best PLC training institute centers in noida which are
ranked the top most in the PLC training sector of India. Reach out to
the PLC training center using the information provided.PLC training in
noida is popular among the students in a great deal which can be
understood clearly if you see the placement records of these institutes.
Monday, May 26, 2014
Best PLC Training Institutes in Pune
Listed the best PLC training institute centers in pune which are
ranked the top most in the PLC training sector of India. Reach out to
the PLC training center using the information provided.PLC training in pune is popular among the students in a great deal which can be understood clearly if you see the placement records of these institutes.
Saturday, April 5, 2014
Best PLC Training Institutes in Chennai
Listed the best PLC training institute centers in chennai which are ranked the top most in the PLC training sector of India. Reach out to the PLC training center using the information mentioned below and also location of the training center is shown through map for your reference.
Wednesday, January 1, 2014
Why PLC is used
The 1st Programmable Logic Controller (PLC) originated by a group of engineers at General Motors, when the company were looking for an alternative to substitute complex relay control systems.
Friday, October 18, 2013
PLC vs Relay logic circuits
Listed below the comparison of PLC vs Relay logic circuits.
- Relays usually used for protection applications (Example: over-current , under-voltage ,Etc). But PLC devices are used for control applications (Example:load shedding) and it needs timer circuit.
- Modern numerical relays have advance microprocessors but PLC is depend on simple processor that can't support the new requirements of systems.
- PLC system is more expensive for a simple circuit than Relay system. However, they can both be used for the same application and they both require an analog timer and a timer socket.
- PLC are used for industrial automation which can be programmed easily but relays as a sequence logic as per process and hence relays are used for isolation purposes.
- Wiring ,maintenance modification are difficult with relay but in PLC,user can easily modify the logic to add number of input and outputs.
- PLC is the much less complex than large relay based system.
- PLC is the very flexible due to network architecture compare to relay panel.
- PLC is the virtually self-documenting compare to relay panel.
- PLC is the very space efficient and less manpower required to install compare to relay panel.
- PLC is the upfront material costs are similar, but savings on
installation, maintenance, and troubleshooting increase rapidly as
system size increases compare to relay panel.
- PLC`s reliability in industry and lab experience demonstrate PLCs comparable to relay system.
- PLCs huge knowledge base in industry compares to relay panel
- PLCs training and operating is very easy to handle its hardware and programming is also easy to learning
- In the PLC have no complicated wiring compare to relay panel.
Relay Logic Circuit | PLC |
---|---|
It is an operating on analog system. | t is an operating on digital system. |
The maximum time any change in input is reflected in any output is t1. | The maximum time any change in input is reflected in any output is t1+t2+…+ Tn. |
Since this is made from analogue components. It is possible to replace. A logic section without stopping execution of other logic sections if wired correctly. | This is made with a digital micro-controller. The micro-controller must be halted to replace a logic section. All other logic sections will stop operation |
Since parallel execution of logic sections, all outputs are a function of one set of inputs. | Since serial execution of logic sections, all outputs may not be a function of one set of inputs. |
What is the logic used in PLC
The first thing needed for automating any industrial process or machine is to determine the sequence of operation or events which are specific to its operation. This sequence is then organized into a set of logic functions.
Logic functions are of two types:
->Combinatory: Where results will depend on only on the present state of the inputs.
->Sequential: Where results depends on the present and past state of the inputs
Then this Logic scheme is actually turned into a physical system using the essential building blocks of the particular technology selected, i. e. Mechanical, Fluidic, Pneumatic, Electromechanical, Electronics.
There are three basic system options which might be open to a design engineer.
->Relay Logic:
It has for many years been the work horse of most electrical installations.
Advantages:
It was simple for small systems, hence cost benefits due to wide range of available coil voltages.
Disadvantages:
As the number of relays increases, it requires larger physical area, coupled with costly enclosures, the labour charges, the schematic and connection diagrams, escalates the final cost
->Wired Logic
->Programmable Logic
Logic functions are of two types:
->Combinatory: Where results will depend on only on the present state of the inputs.
->Sequential: Where results depends on the present and past state of the inputs
Then this Logic scheme is actually turned into a physical system using the essential building blocks of the particular technology selected, i. e. Mechanical, Fluidic, Pneumatic, Electromechanical, Electronics.
There are three basic system options which might be open to a design engineer.
->Relay Logic:
It has for many years been the work horse of most electrical installations.
Advantages:
It was simple for small systems, hence cost benefits due to wide range of available coil voltages.
Disadvantages:
As the number of relays increases, it requires larger physical area, coupled with costly enclosures, the labour charges, the schematic and connection diagrams, escalates the final cost
->Wired Logic
->Programmable Logic
- Improved installation time
- eliminate the need for extensive wiring of timers, relays and other components
- Improved flexibility
- enable control system changes simply by reprogramming
- Much more compact than relay control panels, yet enables complex, high-level control
- Improved reliability
- Selection of the most suitable system is largely dependent on the application, availability and acceptability.
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