DAC Output with PID control


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I'm trying to use the PID to control a SSR.  It needs to turn the SSR on and off based off of a Temp process variable.  I have the PID Output Channel set to PIDOut.  I then use sequence code to either send a 0 or 1 to the SSR channel based off of PIDOut.

When I click on SSR channel and look at the values in the table, I can get it to alternate between 0 and 1, as it should by changing the set point in the PID.  The SSR channel is in DAC0 and the corresponding Vs, but the SSR remains powered.  It will not turn off with a value of 0.  What am I doing wrong?

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I would first make sure you can manually control the SSR.  Once you do that, then work in the PID.  I'd need more detail on your hardware to address the first part.  As to using a PID to control a digital, you need to actually have the PID output to a variable, then create a sequence to pulse the SSR based on the PID output, where, typically, -100 is all off, and 100 is all on. 0 would be 50% on, 50% off.  You can determine the cycle time based on your process.

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