Qwiic Scale Digital Output to NI-USB 6008 Analog Input

Qwiic System
1

Hello,

I had a question pertaining to the Qwicc Scale device. I do not yet own the device, but am considering purchasing one for my application. I have two Omega strain gauges that I would like to use alongside an amplifier 1/2 bridge circuit to form a full Wheatstone bridge. These gauges will read-out through a feed through, and will need to be amplified in some way before passing to an NI-USB 6008 data acquisition assistant.

The Qwicc Scale device seems to suit this application, but I would like some help from applications engineers in clarifying its compatibility. I have a functional program in LabVIEW that is setup to read-in an analog input. It takes a 20 V range at 16-bit, with a 26 mV manufacturer recommended minimum resolution dependency. My questions are the following:

Would the Qwicc Scale be suitable for completing the 1/2 bridge of two 120 Ohm strain gauges?

Would the output signal be translatable to a 16-bit analog input channel?

If not, what adaptations or additions could you suggest for making this a workable configuration?

Are there any more suitable alternatives to this setup that could be used?

Thanks for any help you may provide. Please let me know if I can clarify further.

2

Would the Qwicc Scale be suitable for completing the 1/2 bridge of two 120 Ohm strain gauges?

The Qwiic Scale won't complete the Wheatstone bridge, you'd need some resistors (or more strain gauges) to do that, but as long as you can create a full bridge that can be connected to (and read by) the Qwiic Scale.

Would the output signal be translatable to a 16-bit analog input channel?

Unfortunately no, the Qwiic Scale doesn't have an analog output at all. It's I2C (digital) only. You could read the data with a microcontroller and then produce an analog output with a DAC that corresponds to what you're reading, but that's quite a bit more work than just doing everything analog to start with.

If not, what adaptations or additions could you suggest for making this a workable configuration?

Sadly, none as the Qwiic Scale is purely digital and doesn't bring out any analog data. You need an analog instrument amplifier board for something like what you're trying to do. We don't carry any but you could build one with a instrument amplifier chip or possibly a bunch of op-amps. A google search for 'analog strain gauge amplifier' should point you in the right direction for something like this.