Time Down (Retain)
Instruction Parameters
Supported PLC Series
| XPnA/1R | XPnB | XPnE | XPnF | CP3A/B/P/U CP4A~D/U | CPnE | CPnF | BP | PLC-S |
|---|---|---|---|---|---|---|---|---|
| ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ | ✓ |
Supported Data Registers
| M | X | Y | K | L | F | T | C | S | Z | R | Q | D | @D | Constant | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| t | - | - | - | - | - | - | ✓ | - | - | - | - | ✓ | - | - | - |
| v | - | - | - | - | - | - | - | - | - | ✓ | - | ✓ | ✓ | - | - |
Supported Flags
| Flag | Bit | Support |
|---|---|---|
| Error | F11.0 | ✓ |
| Zero | F11.1 | - |
| Carry | F11.2 | - |
Number of Steps
| Steps |
|---|
| 3 |
Operands
| Operand | Description |
|---|---|
| t | The first operand. Entries are only timer data registers. |
| v | The second operand. Entries are unsigned WORD data registers or constants. This is the value the timer will count down from. The unsigned value range is 0 ~ 65,535 (216-1). The Hexadecimal value range is H0000 ~ HFFFF. Signed value entries will be treated as unsigned values. |
Notice
Error Flag (F11.0) Notice
The error flag, F11.0, will be ON for one scan when the address of the data register assigned by Z exceeds its range.
The valid range of the data register Z is Z128 ~ Z1023 when using Function Block implementation.
Instruction Behavior
The TMR instruction behaves as follows:
- The data register T assigned to t is a BOOL data register.
- TS and TC express the detailed value of the data register T assigned to t.
- TC is a WORD data register used for the current time value of t.
- TS is a WORD data register used for the time setting value of t.
- The value of TS is equal to the value of v.
- TS and TC express the detailed value of the data register T assigned to t.
- The value of TC increases when the instruction is energized.
- When the value of TC equals the value of v, TC energizes or turns ON.
- If TC is affected by the RST instruction, the value of TC is 0, and the timer turns OFF.
- If the TMR instruction deenergizes, TC will retain its value.
- If the value needs to be retained in instances of power failure, save TC to a K data register.
- K data registers support memory latching.
- If the value needs to be retained in instances of power failure, save TC to a K data register.
- The actual time for the timer data register t is calculated as follows:
- Actual Time = v × time unit (100ms or 10ms)
- The timer contact assigned to t can be used as an A or B contact.
- When the timer contact meets the RST instruction, the current value is 0 and the timer turns OFF.
Timer Length
Please refer to the PLC Parameter section for more information about 10ms and 100ms timers.