Chapter 6 Applied Instructions 6.26.2 Explanation of High-speed Output Instructions Symbol S 1 : Pulse output frequency S 2 : Number of pulses to output D : Pulse output device 6_ Explanation 1. This instruction specifies the pulse output ( S 1 , S 2 ) for the device specified in D with no ramp up or ramp down when the frequency changes. S 1 specifies the pulse output frequency range: for open collector output models, the range is between 0 Hz–200 kHz. The unit of the output frequency is 1 Hz. The error rate for 200 kHz is about 0.02% and for 100 kHz it is about 0.01%. The error rate decreases with decreasing frequency.
For example, if the output frequency setting is 199990 Hz, the actual output is 199960 Hz. If the output frequency setting is 99999 Hz, the actual output is 99990 Hz. If the output frequency is out of the valid range, the PLC automatically processes it as the maximum or minimum pulse output frequency. 2. You can change the output frequency specified by S 1 during the execution of the instruction without using the ramp up/down process. The time to change the frequency is when the PLC is scanning the instruction and the instruction has completed output of a full pulse. 3. S 2 specified the number of output pulses. The range is between 0–2,147,483,647.
When you set the number of output pulses to 0, then the number of pulses is not restricted and pulses are output constantly until the instruction is disabled. When the number of output pulses is set to less than 0, no pulses are output. 4. After the instruction starts to output pulses, the number of output pulses specified by S 2 cannot be changed.
6-763 API Instruction Operand Description 2700 D PLSY S1，S2，D High-speed pulse output (without ramp-up/down process) Device X Y M S T C HC D FR SM SR E K 16# “$” F S1 S2 D BOOL WORD DWORD LWORD UINT INT DINT LINT REAL LREAL TMR CNT STRING Data type S1 S2 D Pulse Instruction 16-bit instruction 32-bit instruction － － ES3