how to write program by ladder logic in case of PLC operation

Answer Posted / muhammad uzair

Ladder Logic is simply an interpretation of OR, AND, NOR,
XOR, XNOR, NAND functions. First you solve the problem
using the above functions & then transform the symbols into
those of ladder logic.

Each rung of ladder language typically has one coil at the
far right. Some manufacturers may allow more than one
output coil on a rung.

--( )-- a regular coil, true when its rung is true

--(\)-- a "not" coil, false when its rung is true

--[ ]-- A regular contact, true when its coil is true
(normally false)

--[\]-- A "not" contact, false when its coil is true
(normally true)

The "coil" (output of a rung) may represent a physical
output which operates some device connected to the
programmable controller, or may represent an internal
storage bit for use elsewhere in the program.

Example:
S = X AND ( Y OR Z )

----[ ]---------|--[ ]--|------( )--
X | Y | S
| |
|--[ ]--|
Z

Is This Answer Correct ?    72 Yes 14 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

what would happen if reactive power (kvar)is increased (more)or decreased (less)? how much exact reactive power should be maintained? and what should be done for that

1770


what is meant by flywheel and its role in retardation test

1956


Is there any abbrevation for STUB in Stub bus protection

1487


What is notching in dc machine?

1496


hello if any one have papers vof hpcl or sail, plz send me

1419






what kind of technical test that i need to learn because i have an interview tomorrow.. please someone help me..

1484


What is the difference between solid grounding and impedance grounding?

1532


what is through fault?

1755


Disadventage of cable-gland earthing if any ?

1655


From what on-site components does the HT panel monitoring the bus-bars in a 11kV system take inputs?

1514


CALCULATE THE TOTAL VOLTAGE DROP AND SELECT THE CABLE SIZE IN MM-SQARE FOR A PANEL-262KW AT 110 METER FROM THE SOURCE SUPPLY , SUPPLY VOLTAGE 240/415

2232


Explain thin film resistors and wire-wound resistors

633


advantage and disadvantage of team work?

1253


What is touch potential and step potential?

1618


The Howland current source produces a A Unidirectional floating load current B Bidirectional single-ended load current C Unidirectional single-ended load current D Bidirectional floating load current

1639