PWM and Pid control with MyDaq

[bobby.m]

HI all,

I am currently building a temperature controlled project using labview and the Ni MyDaq. I am using a 230v heating element via a solid state relay as my heating source and a thermistor as my sensor. I have used and created a pwm program using Pid control to achieve my desired setpoint. I'm using the counter channel DIO 3 for my pulse train and AI 0 for my sensor intake. I've included the program below, when i run the program it works fine but eventually i will get the following error

Error-200684

possible reasons:

Pulse duty cycle specified is not supported for this device given the pulse frequency and the counter timebase rate

Data:  1.000000

Specified range Minimum  80.0e-9

Specified range Maximum 999.999

I've messed around with the duty cycle and frequency but this error still comes up. Sometimes it comes up straight away and other times it could take a couple of mins. Does anyone have any suggestions on how i go about fixing this problem.

Thanks

Bobby

[Liam_A]

Hi there Bobby,

I don't think it is a physical limitation of the card, so could you try the following example from the LabVIEW Example Finder please?

In the Example Finder use the Search tab and enter the keyword PWM. The example in question is PWM-Counter Output.vi I think that this example is along the same lines of what you are trying to do.

If you could let us know how you get on then that would also be great.

[pbmebm]

hola bobby.m  como te va con tu proyecto ? sera que me puedes dar una mano seria de mucha ayuda ,,, tengo que realizar un proyecto iguan al tuyo ... si fueras tan amable de inducarme que tipo de sensor utilizaste y como lo metiste a labVIEW   tego entendido que esta targeta acepta termocuplas pero no se como utilizar esta cualidad de la daq... estube revisando tu VI y se ve muy interesante sera que me puedes indicar un poco mas detallado que es lo que haces en el VI..

Gracias