sanyc Posted November 23, 2020 Report Share Posted November 23, 2020 I can't seem to figure out the PWM output for the PLC model as above. From what I understand O0 and O1 can function as PWM output as long as you enable the PWM bit from the software. Done. Now, from what I 've read since this functions as a normal PWM (and not High Speed PWM - I guess its the frequency upper limit that changes), its Time Period is at most 2.5ms? So with f= 1/T max frequency I can get is 400 Hz? Why does the spec sheet states that it can be set up at 3kHz? Next, PWM is suppose to give an average of the total voltage based on the duty cycle. The way I set this up it just turns the Output +24V and 0V based on the duty cycle. Varying my frequency doesn't change a thing on the behavior of my motor, but varying the Duty Cycle causes my motor to spasmodic operation if I set anything below 100 Duty Cycle. Another thing I don't understand is the value of the frequency; does 0-3000 correspond to 0-3 kHz ? If so why does the software sets measuring unit to milliHz? Attached is my program for PWM in rung 12. Thanks Test.ulpr Quote Link to comment Share on other sites More sharing options...
AlexUT Posted November 23, 2020 Report Share Posted November 23, 2020 Hi, If you are talking about Unistream - PWM frequency is in milli-Hertz. See details in Help. *Seems you mix Vision and Unistream when talking about Ladder FB PWM SCAN.. B.R. Quote Link to comment Share on other sites More sharing options...
sanyc Posted November 24, 2020 Author Report Share Posted November 24, 2020 Thanks Alex, it all cleared when you said I am mixing the the controllers. It worked. Quote Link to comment Share on other sites More sharing options...
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