USB Load Cell
This page shows you how you can connect a load cell to a PC/Laptop/Tablet* and how you can use the data…
A simple USB load cell system, using a Low Cost 10″ tablet* as a large display.
Hardware
You can add a USB connection to any of our load cells by selecting the USB module from the “Output” list box on the load cell product page. The miniature In-Line USB module (58mm x 33mm x 13mm) then becomes an integral part of the load cell cable (there’s also a separate USB Load Cell Adapter for retrofitting to existing load cells). The cable is then plugged directly into a spare USB** port on your device, giving you a simple working system. You can connect as many USB load cells to your device as you have spare USB** ports. If you need to connect more load cells than you have ports, you can add more ports by using a USB Hub.
Miniature In Line USB module
USB Hub for Multiple Load Cells
Software
Once you’ve connected your load cell and PC/Laptop/Tablet*, the free software will display live readings that can also be logged to a CSV file (max 24 load cells). The logged data can then be loaded into a spreadsheet, like Excel, to produce graphical reports etc. If you want to try the free software now, you can download and install the single-channel version, as it has a “Demo” mode. The demo mode lets you see all the available settings without having to have a load cell connected. Also, if your device is connected to your network you can access any logged data from other PC’s on the network.
More advanced users/programmers can take advantage of the DLL driver and create their own windows applications (Driver file comes with example source code for Visual Net and C programs). The modules can also be set up to produce a constant stream of ASCII values which is handy for interfacing with other terminal type programs/equipment.
Example CSV file in Excel showing logged Data (Time stamp, milliseconds and load cell output)
PC USB Module Specification
| Parameter | Min | Typical | Max | Units/Notes |
|---|---|---|---|---|
| Average Operational Current (normal mode) | 70 | 80 | mA@350 Ohm | |
| Operating Temperature Range | -40 | 85 | Deg C | |
| Storage Temperature Range | -40 | 85 | Deg C | |
| Humidity | 0 | 95 | %RH |
Bridge Measurement
| Measurement | Min | Typical | Max | Units |
|---|---|---|---|---|
| Offset Temperature Stability | 1 | 4 | ppm/C | |
| Gain Temperature Stability | 3 | 5 | ppm/C | |
| Offset Stability with Time | 35 | 160 | ppm of FR | |
| Gain Stability with Time | 300 | ppm of FR | ||
| Non Linearity before Linearization | 5 | 25 | ppm of FR | |
| Internal Resolution | 16 Million | Counts/Divs | ||
| Resolution @ 1Hz Readings (Noise Stable) over 100s | 200,000 | Counts/Divs | ||
| Resolution @ 10Hz Readings (Noise Stable) over 100s | 120,000 | Counts/Divs | ||
| Resolution @ 100Hz Readings (Noise Stable) over 100s | 50,000 | Counts/Divs | ||
| Resolution @ 500Hz Readings (Noise Stable) over 100s | 18,000 | Counts/Divs | ||
| Signal Filter | Dynamic recursive type user programmable | |||
Module Dimensions: 58mm x 33mm x 13mm
Cable length from USB connector to module: 300mm
Total cable length: as selected in “Termination” option on load cell product page.
* Windows OS only.
** USB Type A connector (other USB types available on request).
