Answer / 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

Answer / d.balaji

hi. if u know the true logic for all the gates like AND,OR
etc,. its easy to write a program by using that gates.i
suggest u please the site www.abb.com this will give what
ever information u want,.

Answer / salah

yes

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