Eaton ELC-PB, Programming Manual

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EL C Pro g rammi ng Manu al
F o r m o r e i nf o r m a t i o n v i sit : w w w.eato n. co m MN05003003E
1-6
Ladder Diagram
Structure
Explanation Instruction Available Devices
Multiple output branches
MPS
MRD
MPP
None
Output coil
OUT Y, M, S
S
Step ladder
STL S
Basic / Application
instruction
-
Basic instructions and API
instructions. Please refer to
chapter 3 Instruction Set
Inverse logic
INV None
1.5.1 Creating a ELC Ladder Program
Editing a program should start from the left side bus line to the right side bus line, and from top to
bottom. However, the right side bus line is omitted when editing in ELCSoft. A single row can have
a maximum of 11 contacts. If more than 11 contacts are connected, a continuous symbol “0” will be
generated automatically and the 12th contact will be placed at the start of next row. The same input
points can be used repeatedly. See the figure below:
Y1
0
0
X0 X1 X2 X3 X4 X5 X6 X7 X10 C0 C1
X11 X12
X13
When evaluating the user program, the ELC scan starts from left to right and proceeds to the next
row down until the ELC reaches END instruction. Output coils and basic / application instructions
are output instructions and are placed at the right of ladder diagram. The sample program below
explains the execution order of a ladder diagram. The numbers in the black circles indicate the
execution order.
X0 X1 Y1 X4
M0
X3 M1
T0 M3
Y1
TMR T0 K10