Instruction Parameters
Supported PLC Series
| PLC-AES | PLC-FB | PLC-ES |
|---|---|---|
| ✓ | ✓ | ✓ |
Supported Data Registers
| M | X | Y | K | L | F | T | C | S | Z | R | Q | D | @D | Constant | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| S1 | ✓ | ✓ | ✓ | ✓ | ✓ | – | – | – | – | ✓ | – | ✓ | ✓ | ✓ | ✓ |
| S2 | ✓ | ✓ | ✓ | ✓ | ✓ | – | – | – | – | ✓ | – | ✓ | ✓ | ✓ | ✓ |
| D | ✓ | – | ✓ | ✓ | ✓ | – | – | – | – | ✓ | – | ✓ | ✓ | ✓ | – |
Supported Flags
| Flag | Bit | Support |
|---|---|---|
| Error | F11.0 | ✓ |
| Zero | F11.1 | – |
| Carry | F11.2 | – |
Number of Steps
| Steps |
|---|
| 4 |
Operands
| Operand | Description |
|---|---|
| S1 | The first operand. Entries are REAL data registers or constants. The value range is -1.7014118e+38 ~ 3.4028237e+38 (2-127 ~ 2128). |
| S2 | The second operand. Entries are REAL data registers or constants. The value range is -1.7014118e+38 ~ 3.4028237e+38 (2-127 ~ 2128). |
| D | The third operand. Entries are only REAL data registers. This is where the difference is saved. |
Float Representation
| Mantissa | Exponent | Sign |
|---|---|---|
| Bit 0 ~ Bit 22 | Bit 23 ~ Bit 30 | Bit 31 |
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 @D exceeds the range of the data register, D. The range of the data register, D, is dependent on the CPU type. F11.0 turns ON when the value of the data for adding exceeds the data register assigned to S1 or S2.
Tip: Operand Subtraction Format
S2 is subtracted from S1. (S1 – S2)
Ladder Diagram Examples
ESUB
The ESUB instruction subtracts a REAL value, S2, from a REAL value, S1, and saves the difference in an assigned REAL data register, D.
When M0.1 is powered ON, the REAL data register, D11, is subtracted from the REAL data register, D9, and the difference is saved in the REAL data register, D13.
Memory Monitor
ESUBP
The ESUBP one-shot instruction subtracts a REAL value, S2, from a REAL value, S1, and saves the difference in an assigned REAL data register, D. Every time this instruction executes, it energizes the output only once.
When M0.1 is powered ON, the REAL data register, D11, is subtracted from the REAL data register, D9, and the difference is saved in the REAL data register, D13.
Memory Monitor
