labview excitation voltage

[mekdeng]

Hello All,

Can Labview, without any external source supply excitation voltage? if yes how much?

[devchander]

You mean, without any hardware????

[mekdeng]

Yes Devchander.

As I said in my previous message, I am using DC-50LP connector block, PCI-DAQ card and LabVIEW software. Can LabVIEW supply excitation voltage with out any external signal conditioning system? Can I be able to power strain gages with the hardware and software I am using?

Regards

Mekdeng

[devchander]

Hi Mekdeng,

Well, if you are having a AO/Multifunction DAQ card, you can indeed generate an analog output voltage.

plz take a look at any analog output examples shipped with Labview to get an idea on how to go about it.

If you plan to use it as a voltage source with its generated AO characterstics/specs( absolute accuracy, output coupling, output impedence, current drive, stability) i do not foresee any problems.

Since you plan to use it as an excitation for strain gage, check if these AO characterstics suit the strain gage excitation requirements.

Regards

Dev

[Ryan_V[DE]]

Mekdeng,

Unfortunately, the analog output on your DAQ card can only source a very small current (~5mA). I would recommend using the 5V output of the card as your excitation. In addition to the voltages on your bridge completion network, I would also read the 5V supply so you know the exact voltage supplied and are able to more accurately calculate the strain.

Hope this helps,

[2c worth]

You can find an application note on low cost (US$79) strain measurement
using LabVIEW at the following link

http://www.emant.com/325007.page

"Ryan V" <x@no.email> wrote in message
news:1132697446732-291782@exchange.ni.com...
> Mekdeng,
>
> Unfortunately, the analog output on your DAQ card can only source a
> very small current (~5mA). I would recommend using the 5V output of the
> card as your excitation. In addition to the voltages on your bridge
> completion network, I would also read the 5V supply so you know the
> exact voltage supplied and are able to more accurately calculate the
> strain.
>
> Hope this helps,