IAI America DS-S-T1 - Manual (Page 15)

Page 13
 Carry out a command when an input condition is established, and turn the output port ON, if output is
designated. When not established, go on to the next step regardless of the next command (ex. WTON,
WTOF). The designated output port remains the same , however it needs to be monitored carefully.
‚ If there is no conditioning set up, carry out command unconditionally.
ƒ If condition is used as "negative condition", then place an "N" (NOT).
„ Input/output port & flag can be used for condition.
 Actuators motion control commands: becomes OFF immediately after the command starts to be executed,
and becomes ON when the command is completed.
Computation commands: when the result becomes a certain value, it turns ON, and it stays OFF otherwise.
‚ Output port and flag can be used for output section.
(1) The conditions before the commands are equivalent to "if ~ then" statements in BASIC language.
Putting this in a ladder
diagram,
7.2 Commands
The outstanding feature of the SEL language is the simplicity of its command structure which eliminates the need for a
compiler and allows high speed operation with just an interpreter.
7.2-1 SEL Language Structure
One step of the command has the following structure.
(2) Output is set based on the result of the command execution.
ò
7. Programming
n o i s n a p x E
) R O · D N A (
n o i t i d n o C t u p n I
) g a l F · O / I (
d n a m m o C
t s o P
) g a l F · t r o p t u p t u O (
d n a m m o C 1 d n a r e p O 2 d n a r e p O
IF ~ THEN ELSE
○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○
To the next step
ò
Command Post Operand 1 Operand 2
Operand 1 Operand 2 Command Post
Operand 1 Operand 2 Command Post