USB-6341 full bridge measurement

[bpwtesting]

Is it possible to perform a full bridge measurement with a strain gauge force sensor using the usb-6341?

[ZYOng · Accepted solution]

Possible but not suitable for the following reasons:

1. USB-6341 does not have a built-in excitation. You might need AO or external excitation voltage.

2. USB-6341 might not have enough resolution. It has a 16-bit ADC with the smallest input range of 0.2V. As a comparison, NI-9237 has 24-bit with 25mV/V input range.

3. NI-DAQmx does not support using USB-6341 for strain measurement. You can only use the voltage input task and then do some scaling on your own.

[Antoniooh · Accepted solution]

The output of the bridge is in the order of milivolts and the minimum voltage for the USB card is 200mV plus minus, so is not the correct card to read the bridge, it would be better to use a signal conditioner between the bridge output and the USB card.

[Antoniooh]

Sorry, 200mV is not the minimum voltage, is the minimum input range that you can set the card to read.