S5 AWL Command: = (Assign)
S5 AWL instruction = (Assign): Writes the current VKE to a boolean operand. Non-latching — output follows VKE directly.
S5 AWL Command: = (Assign)
The = instruction writes the current VKE value to a boolean operand. Unlike S/R, this is a non-latching operation — the output follows the VKE directly. When the VKE becomes FALSE, the output becomes FALSE.
Syntax
= <operand>
S7 Equivalent
| S5 AWL | S7 STL | S7 SCL |
|---|---|---|
= A 4.0 | = Q 4.0 (EN) / = A 4.0 (DE) | Output := condition; |
Code Example
U E 0.0 // Switch (maintained)
U E 0.1 // Safety interlock
= A 4.0 // Motor follows switch directly
A 4.0 is TRUE exactly as long as E 0.0 AND E 0.1 are both TRUE. When either goes FALSE, A 4.0 goes FALSE immediately.
Difference: = vs. S/R
| = (Assign) | S (Set) / R (Reset) | |
|---|---|---|
| Behavior | Output = VKE (follows directly) | S: latches TRUE / R: latches FALSE |
| When VKE is FALSE | Output goes FALSE | S: output stays unchanged |
| Typical use | Direct control, indicator lights | Motors, valves, anything that needs start/stop |
Important: VKE Reset After =
After the = instruction, the VKE is reset. The next U/O starts a new logic chain.
Related Commands
Part of the S5 AWL Command Reference. Maintained by PLCcheck.ai.
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