Load Cell DAQ hardware (and software) suggestion

[straits]

Hi! I am a student working on a mechanical engineering project which revolves around designing a torsion testing machine. The machine will be reading the load applied to a shaft at a certain offset with the use of a tensile load cell. The load cell specifications are as follows:

S-type

Code: RLT0010

Excitation voltage: 10V

Output: 2mV/V

Capacity: 98 N or 10 kgf

Bridge Resistance: 350 ohms

The connector is a 5-pin DIN type.

I am new to interfacing measurement hardware to computers. The initial idea was to get a readout on an indicator on LabView. What kind of hardware do I need in order to convert the load cell signal, and feed it to a PC where it will be displayed through a LabView VI?

Thanks in advance.

[Pete.Dunc]

Hi straits,

Thanks for joining the community! 

Your load cell has an analogue voltage ouput, so we need hardware that can take an analogue input voltage.  There is an incredibly broad range of products that NI provides for that purpose - however it will be up to you to decide which specification you require (consider resolution, sampling rate, etc).

There are also a number of platforms - we offer low-cost USB interfaces, which will get you up and running with a low channel count.  Additionally you may consider the CompactDAQ - this is a modular platform where you can swap in/out modules for different measurement types, if you think the project might progress and require more channels of differing measurement types - this would be the way to go.  There is a fairly high level comparison of our offerings here.

Please let me know if you have any questions about this.

[straits]

Thanks for the reply. I already have an amplifier used with this particular load cell, and it can be connected to a computer via a USB port. I'm wondering if I can use this port in a LabView VI with no additional hardware for signal conditioning. I've used a couple of products such as the NI 9219 in basic experiments, but it seems that LabView needs to recognize the hardware as the latter.

Thank you in advance.

[Pete.Dunc]

Who manufactures the USB device?  You can certainly communicate with devices via USB using the VISA API, however you will need to know the commands to send/receive.  The manufacturer may already have created a driver for the device, try having a look on the Instrument Driver Network to see if one exists.

[straits]

I'll check the details of what I have ASAP and fill it into the thread. I'm assuming that the USB interface you mentioned connects some kind of ADC (for the load cell) to the computer?

[Pete.Dunc]

If the load cell manufacturer has provided an interface to USB - there has to be a change from analogue to digital - as USB is itself digital.  How they have performed that conversion, and how we can communicate with the device should be included in the documentation.