What is the PLC Level & type.
Answers were Sorted based on User's Feedback
Answer / md ziaul haque
PLC is programmable logic control its good for on off control there is no level these days our science is very developed. They developed PLC all DCS feature is there
| Is This Answer Correct ? | 10 Yes | 7 No |
Answer / md.nayeemuddin
A programmable logic controller (PLC) or programmable
controller is a digital computer used for automation of
electromechanical processes, such as control of machinery on
factory assembly lines, amusement rides, or light fixtures.
PLCs are used in many industries and machines. Unlike
general-purpose computers, the PLC is designed for multiple
inputs and output arrangements, extended temperature ranges,
immunity to electrical noise, and resistance to vibration
and impact. Programs to control machine operation are
typically stored in battery-backed-up or non-volatile
memory.
As an example, say a facility needs to
store water in a tank. The water is drawn from the tank by
another system, as needed, and our example system must
manage the water level in the tank.
Using only digital signals, the PLC has two digital inputs
from float switches (Low Level and High Level). When the
water level is above the switch it closes a contact and
passes a signal to an input. The PLC uses a digital output
to open and close the inlet valve into the tank.
When the water level drops enough so that the Low Level
float switch is off (down), the PLC will open the valve to
let more water in. Once the water level rises enough so that
the High Level switch is on (up), the PLC will shut the
inlet to stop the water from overflowing. This rung is an
example of seal-in (latching) logic. The output is sealed in
until some condition breaks the circuit.
| |
| Low Level High Level Fill Valve |
|------[/]------|------[/]----------------------(OUT)---------|
| | |
| | |
| | |
| Fill Valve | |
|------[ ]------| |
| |
| |
An analog system might use a water
pressure sensor or a load cell, and an adjustable
(throttled) control (e.g. by a valve) of the fill of the tank.
| Is This Answer Correct ? | 3 Yes | 5 No |
I WANT TO KNOW SOME BASIC CONCEPTS RELATED TO INSTRUMENTATION
How to force the bit in GE Mark V?
How to connect another 24 volt dc power supply in circuit when previous power supply has become weak.what is the connection?
2 Answers Bhole Baba Dairy Industries,
what do you mean by smart instruments ? define ? give an example?
2 Answers Flour Tech Engineers (P) Ltd,
How to find out the current of two motors having same power consumption but different RPM?
What s PDS & PDMS tools ?its role in instrumentation?
what are the problem's will accure in dcs or plc hadware and what are the solution for it?
cascade controller is feed back or feed forward or both
What is the solution if rotork motorised control valve showing pink Colour in dcs.
3 Answers Bhushan Power Steel,
why r using 250 resistances
hello friends, can you please send me the model paper or question paper to be prepared for hpcl examinations????????? You can mail me at rahim_here@yahoo.com waiting for your reply........... help me .. plz.....
Hi i m B.E. In elect. & comm. I m workin in bio mass plant from 6 mnths as inst. Engg. but now i m in dept. Of operation as shift engg...which is best operation or inst. 4 me? M confusd..plz help and reply me..
Civil Engineering (5086)
Mechanical Engineering (4456)
Electrical Engineering (16639)
Electronics Communications (3918)
Chemical Engineering (1095)
Aeronautical Engineering (239)
Bio Engineering (96)
Metallurgy (361)
Industrial Engineering (259)
Instrumentation (3014)
Automobile Engineering (332)
Mechatronics Engineering (97)
Marine Engineering (124)
Power Plant Engineering (172)
Textile Engineering (575)
Production Engineering (25)
Satellite Systems Engineering (106)
Engineering AllOther (1379)