Is this method OK for creating a PWM signal

[TecRix]

I'm building a system to control heater output using PWM to drive an SSR.  I'm not concerned about phase control or frequencies above 100HZ. 

I have run it on a cRIO 9381 module, analog out into an SSR with success.  My concern; is this a resource heavy method or ?

Please take a look at the pic of the VI and let me know if this is viable and what are the drawbacks.

[johnsold]

The analog output current drive specification for the NI 9381 is 1 mA. You cannot drive the SSR with 1 mA.

Software timing is not very precise, but you do not seem too worried about that.

You take the output of the function generator, extract just the first element of the array, and then write that to the AO.  It is very unlikely that you will get a PWM waveform.

Lynn

[TecRix]

Good catch on the 1 mA, Lynn.  Thank you for the input!

I'm am able to flash the LED on the SSR at various frequencies and duty cycles - I'm preparing for a NI-9472 module to arrive and start real temperature control testing/development.  

As I add more features to the VI, including Thermocouple feedback, I may appreciate the timing control, especially relating to the rise time limitations of the SSR.