Control Relay Flags
Control Relay Flags (F011)
The control flags, F011, provide critical status indicators for various PLC operations.
These flags are useful for monitoring error conditions, operation results, and specific system states.
| Control Relay Flags | |||
|---|---|---|---|
| Flag Bit | Name | Description | Use Case |
| F011.0 | Operation Error | ON (1) when an operation error occurs | Detect and respond to operation errors |
| F011.1 | Zero | Indicates that the result of an operation is 0 | Monitor 0 results in arithmetic operations |
| F011.2 | Carry | Indicates a carry bit result from an arithmetic operation | Useful for overflow detection in calculations |
| F011.8 | All Outputs OFF | ON (1) when all outputs are turned OFF | Verify complete shutdown of outputs |
| F011.9 | DPRAM Access Error | Indicates a Dual Port RAM (DPRAM) access error Details are stored in the F007 flag | Diagnose DPRAM-related issues |
F011.0 - Operation Error
Description
The operation error flag is ON (1) when an error occurs during a PLC operation.
This could be due to invalid instructions or incompatible operations.
Use Case
- Detect operation errors in real time.
- Trigger alarms or diagnostic routines to respond to faulty operations.
F11.0 OFF
F11.0 ON
F011.1 - Zero
Description
The zero flag is ON (1) when the result of an arithmetic or logical operation equals zero.
Use Case
- Monitor calculations to detect zero results.
- Useful in conditional operations or error-checking logic.
F11.1 OFF
F11.1 ON
F011.2 - Carry
Description
The carry flag is ON (1) when a carry bit is generated during arithmetic operations, indicating an overflow in the calculation.
Use Case
- Detect overflow conditions during addition or subtraction.
- Ensure accurate handling of arithmetic results.
F11.2 OFF
F11.2 ON
F011.8 - All Outputs OFF
Description
The all outputs OFF flag is ON (1) when all output points of the PLC are deactivated.
Use Case
- Verify complete shutdown of system outputs.
- Monitor system safety during idle or maintenance states.
F11.8 OFF
F11.8 ON
F011.9 - DPRAM
Description
The DPRAM error flag is ON (1) when there is an issue accessing the Dual Port RAM.
Additional details are stored in the F007 flags for more in-depth diagnostics.
Use Case
- Diagnose issues with DPRAM access, such as read/write errors.
- Trigger fault routines to handle memory access problems.
F11.9 OFF
F11.9 ON
