IO-D16A3-TO16 Output 0 Physically on, Visilogic says it is not

[alexmoskos]

Hi,

 

I have a V120-22-R1 connected to an Expansion module that is connected to a IO-D16A3-TO16. I am trying to do PWM through output 0 on the IO-D16A3-TO16 (Source using Pin 8), which is Output 32 in my Visilogic HW configuration.

 

What I am finding is that if my Output is Off but then the frequency Input for it is changed to any number above 0, the physically output turns on and the LED indicator on the module turns on but Visilogic does not recognize that the output is on. What I really I want to do is store a frequency for the output and just turn on the Output bit when I feel like it but if I store a frequency value, the physical output is always on and visilogic doesn't know if it is on or off. I can change the visilogic ladder on and off but there is no physical change to the module output pin, it just stays on.

 

Any idea why this is? What am I missing?

 

Thanks

[dan]

Hi,

 

If you are using a PWM output, the duty cycle will determine the percentage the output will be on for over the given frequency. (0-1000).

 

If the duty cycle is set to 1000, then the output will always be on over set frequency. 

 

Try setting the duty cycle to 0 and see if the output is still on. also, attempt to set a frequency of 1000 to test. 

 

Dan.