Output Latch (OTL)
This information applies to the
CompactLogix
5370, ControlLogix
5570, Compact GuardLogix
5370, GuardLogix
5570, Compact GuardLogix
5380, CompactLogix
5380, CompactLogix
5480, ControlLogix
5580, and GuardLogix
5580 controllers.The Output Latch (OTL) instruction sets (latches) the data bit.
When the rung condition is true, the OTL instruction sets the data bit to true. The data bit remains true until it is cleared, typically by an OTU instruction. When the rung condition is changed to false, the OTL instruction does not change the status of the data bit.
Available Languages
Ladder Diagram
Operands
IMPORTANT:
Unexpected operation may occur if:
- Output tag operands are overwritten
- Members of a structure operand are overwritten
- Except when specified, structure operands are shared by multiple instructions.
Ladder Diagram
Operand | Data Type | Format | Description |
|---|---|---|---|
Data bit | BOOL | tag | Bit to be modified. There are various operand addressing modes possible for the data bit, see Bit Addressing for examples. |
Affects Math Status Flags
No
Major/Minor Faults
None specific to this instruction. See Index through arrays for array-indexing faults.
If the operand is an indirect array reference and the subscript is out of range, then the controller does not generate a major fault when the OTL instruction is false.
Execution
Ladder Diagram
Condition/State | Action Taken |
|---|---|
Prescan | N/A |
Rung-condition-in is false | Set Rung-condition-out to Rung-condition-in. |
Rung-condition-in is true | Set Rung-condition-out to Rung-condition-in. The data bit is set to true. |
Postscan | N/A |
Example
Ladder Diagram
When enabled, the OTL instruction turns the light on.
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