Señal incoherente en modulo 6008

Hola estimados(as), trabajando con un compañero en un trabajo de Tesis, dentro del sistema, estamos recibiendo y enviando una señal de 0-5 volts a dos calefactores a traves de un modulo Ni 6008, los problemas son los siguientes:
1- Enviando el maximo de voltaje(correspondiente a 1700 watts aprox) el sistema responde bien, mostrando en los indicadores del labview dos voltajes( uno para cada calefactor) cercanos a 5, pero sucede que al reducir el voltaje a Cero( de manera drastica), labview aun muestra el voltaje maximo.... este valor solo disminuye si bajamos el voltaje a los calefactores de manera escalonada, esto es, 5--> 4--> 3---> 2--> 0 volts.
ese es el primer problema, y el segundo es:
2- Aun cuando tenemos en cero el voltaje de salida a los calefactores, labview muestra que dichos equipos estan recibiendo voltajes que oscilan entre 0,8. 1,3, valores que deberian ser cero ni no muy cercanos a éste.
Muchas gracias.

Hola Niko!
En la mayor While Loop, debe haber una función "Wait (ms) o Wait Until Next ms Multiple", para temporizar el loop con el fin de dar tiempo para el procesamiento de los datos. Una vez que haya escogido el modo de adquisición, " 1 sample (On demand)", la adquisición sólo será posible cuando existir una demanda de datos. Cuando se cambia el valor de forma abrupta, no hay tiempo para el VI para entender la variación, y no haberá demanda, entonces el 6008 no adquirirá nada y mostrará el último valor adquirido.
Otra alternativa es utilizar el modo de adquisición "Continous Samples", en la que se obtiene un número determinado de muestras continuamente una frecuencia de muestreo determinada.
Haga una tentativa con las sugerencias anteriores.
Att.
Felipe Flores
Felipe Flores
Engenharia de Aplicações
National Instruments Brasil

Similar Messages

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    Hola.
          Sigue unos links para su consulta.
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         http://zone.ni.com/devzone/cda/tut/p/id/6951
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    Attachments:
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    Oops..  Just realized that this got posted in the Motion Control Forums... Meant for it to go in the MIO forums.  Sorry!
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    Message Edited by e-Cash-Money on 03-17-2006 04:30 PM
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    DE For Life!

  • My daq 6008 wil not drop the 5V after the VI is stopped, i have a digital signal going from the error out on the daq in the while loop to the error in on the daq outside the while loop and a boolean going to the data of the daq outside

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