D-16
The structure and explanation of ladder diagram:
Ladder Diagram Structure
Explanation
Command
Equipment
Normally open, contact a
LD
X, Y, M, T, C
Normally closed, contact b
LDI
X, Y, M, T, C
Serial normally open
AND
X, Y, M, T, C
Serial normally close
ANI
X, Y, M, T, C
Parallel normally open
OR
X, Y, M, T, C
Parallel normally closed
ORI
X, Y, M, T, C
Rising-edge trigger switch
LDP
X, Y, M, T, C
Falling-edge trigger switch
LDF
X, Y, M, T, C
Rising-edge trigger in serial
ANDP
X, Y, M, T, C
Falling-edge trigger in serial
ANDF
X, Y, M, T, C
Rising-edge trigger in parallel
ORP
X, Y, M, T, C
Falling-edge trigger in parallel
ORF
X, Y, M, T, C
Block in serial
ANB
none
