The Structure And Explanation Of Ladder Diagram - Delta Electronics AC Motor Drive VFD-E User Manual

Appendix D How to Use PLC Function|
16-bit binary number, i.e. a word, in each register. It uses two continuous number
of data register to store double words.

The structure and explanation of ladder diagram:

Ladder Diagram Structure
D-10
Equipment indication: D0, D1,...,D29. The symbol of equipment is D and
the number uses decimal.
Explanation
Normally open, contact a
Normally closed, contact b
Serial normally open
Parallel normally open
Parallel normally closed
Rising-edge trigger switch
Falling-edge trigger switch
Rising-edge trigger in serial
Falling-edge trigger in serial
Rising-edge trigger in parallel
Falling-edge trigger in parallel
Block in serial
Block in parallel
Command
LD
LDI
AND
OR
ORI
LDP
LDF
ANDP
ANDF
ORP
ORF
ANB
ORB
Revision June 2008, 04EE, SW--PW V1.11/CTL V2.11
Equipment
X, Y, M, T, C
X, Y, M, T, C
X, Y, M, T, C
X, Y, M, T, C
X, Y, M, T, C
X, Y, M, T, C
X, Y, M, T, C
X, Y, M, T, C
X, Y, M, T, C
X, Y, M, T, C
X, Y, M, T, C
none
none