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 |
How to Calibrate Coriolis Flow transmitter in field
We are using Rosemount 5400 series Radar Level Transmitters in all types of Sump Applications having oily water hdrocarbon petrochemical nature. What we are facing the problem frequently is that always getting reading frezzed at some value. If we do power recycling , sometimes it is working . then making same freezing problem. If anybody faced before such type of problem and also having solution , Please give the answer.
What is an instrumentation amplifier? How is it better than a differential amplifier when handling outputs from a wheatstone's bridge?
What is zero elevation and zero suppression?
Can anyone say that formula of Converting the Diff. Pressure into Flow in Kg/Cm2 or any explaniation of Orifice Plate, Beta Ratio , How to calculate
why we are using ungrounded RTD sensor and what is difference between grounded RTD and Ungrounded?
What output voltage the proximity switch shows when it is in open enviornment?
Why plc require in analog input 4-20amp & 0-10 volt?
Identify the electrical variable that is either directly or inferentially used by various instruments to determine the value of a measured variable.
Dear Friends, we are planning to design Power distribution and Fiber optic in the same cabinet.Like Front side Fiber optic and Rear side Power distribution.Is it any possibility of problem occurs like interference etc? Your answer is highly appreciate.
How do you calibration D.P transmitter? ?
what is the diffrence between LCN and UCN