6.17.2 Pulse width modulation
Input/output Operand
Data type
% IW, QW, AIW, AQW, MW, VW, T, C, SMW, LW, *MD, *VD, *LD Double word
T IW, QW, AIW, AQW, MW, VW, T, C, SMW, LW, *MD, *VD, *LD Double word
Bit
OUT
Q
Pulse width modulation (PWM) instruction
initializes the PWM hardware and sends high
speed pulses.
The input value of "%" =conduction time/period.
The input value of "T" is the period of the pulse
PWM description:
1.The unit of T is 1ms.
2.If the input value of "%" is 0 ,then the instruction does not output
the pulse.If the input value of "%" is equal to 100,the value of output
pulse is always 1.
3.When the pulse is sending, you can change the value of “ % ” and period
of the pulse . Then the value of “ % ” and period of pulse will change.
4.If the value of enable bit is 0,pulse sending will stop.When the enable
bit is changed from 0 to 1 ， PWM instruction restarts sending pulse.
For example:
The pulse period is 500 ms, the conduction time is 300 ms.
Attention:
Output point must be high speed output point.
For different PLC,the addresses of high speed output points may be different.
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