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LoadVUE and LoadVUE Lite User Guide

Insert the LoadVUE CD-ROM into your drive. The installation Wizard should start up automatically. If it does not, click Start...Run.... and use the Browse button to select X:\setup.exe where X: stands for the letter of your CD-ROM drive. Click OK until the LoadVUE setup screen appears. Click Next.

Select the installation folder. Click Next twice and LoadVUE will be installed.

If you are using LoadVUE with iLoad Digital USB load cells directly plugged into your PC, please plug in your load cells now and install the drivers following the instructions in the section Driver Installation and Operation of iLoad Digital USB Load cells.

To run LoadVUE, click All Programs...LoadVUE or double-click on the Desktop shortcut for LoadVUE.

 

The COM Ports Setup screen will be shown. If you have attached one or more load cells to the computer's USB ports, LoadVUE will automatically detect the attached load cells. You can select or deselect one or more channels to monitor. At least one channel must be selected.

Click OK to continue. LoadVUE will now restart.

The LoadVUE main window is now shown with the default layout for displaying readings from up to 4 load cells as well as the total load. Peak and Low loads are also shown.

Click on Channels to view a collapsed layout as shown. The individual load cell readings are hidden and just the total is displayed.

Click on Log Settings to view an expanded layout that displays the log readings.

You can select the number of load cells readings that are averaged for display by clicking on the Options... button. Averaging more readings will reduce the noise level while fewer readings will improve the frequency response. On this screen you can also select your preferred display units: lb, kg, N (Newton), or kN (kiloNewton).

Click Tare to zero the load on the load cells. All four load cells and total will now display 0. (Further load cell readings will subtract the load at this point).

Click Start to start reading the load cells. The load cells will be polled as fast as possible but the data is displayed at a more human-readable rate.

Click on Increase Decimals or Decrease Decimals to adjust the decimals displayed. This option is available only when the load cells are being read.

Click on Log to File to log the load cell readings to a comma separated file (.CSV) that can be read by Microsoft Excel. Logging to screen is available only be up to 1 reading/sec (1 sec polling interval) and slower rates, but logging to file can be done at the higher speeds. At the 'Maximum' setting, logging is done as fast as the load cells can be polled. This rate of course depends on the hardware. Higher CPU speeds and/or multi-core processors will yield better performance.

Click on the arrow next to the Log Interval on the status bar to set the rate at which data is logged to file.

Click on the arrow next to the Units on the status bar to change the units in which the load is displayed.

Click on the Graph button to display a graph of the load on each load cell as well as the total load. Peak and Low loads are also shown.

Select Set Graph Limit... from the menu on the graph window to set scaling options on the time axis (x-axis) and the load axis (y-axis).

Enter the maximum time-axis range in seconds in the Range field. (Minimum: 5 sec). (You must close the graph and click on the Graph… button again for this change to take effect.)

Select Auto on the Load-Axis options for the load axis to scale automatically. You can specify the maximum and minimum load axis values on the graph by selecting Fixed and entering the values in the Maximum and Minimum fields.

If you see the error message below, it may sometimes be caused by a temporary problem in the COM port connection or the load cell connections.

Check the connections and try again. As a last resort, close LoadVUE and restart the program. All data in the saved datasets and log files will be preserved. You may also be able to solve this problem by unplugging the relevant load cell from the USB port and plugging it back in after a second or two and then using the Options button to poll the ports again.

The LoadVUE Calibrator program can be used to recalibrate a USB load cell. Click Start...Programs...LoadVUE...LoadVUE Calibrator to launch the program. (The LoadVUE program must be closed before running LoadVUE Calibrator).

The calibration window displays a list of available COM ports. Select the load cell to calibrate by choosing the appropriate COM port. The load cell part number, serial number and capacity (in lb) are queried and displayed. Any stored previous calibration is also indicated. You can either choose to load a previous calibration, or start a new calibration.

Click on Calibrate to go to the calibration screen.

With no load applied to the load cell, enter 0 as Load for point 1 and click on Read Sensor to read the load cell values for that load.

Similarly enter various applied load values for all the nine points and click to get the load cell readings. Click on Curve Fit to fit calibration parameters followed by Save Fit to save this dataset. The fit coefficients will be displayed if available. (Two Point Fit fits only the lowest and highest points).

Click Burn Quadratic Coefficients to write the calibration data to the load cell. (Only the quadratic coefficients can be burned into the load cell. However, the other calibration methods can be used in software mode. For example, if only two weights are available, the Two-Point method can be used to calibrate the load cell. If more accuracy than the quadratic fit is desired, a cubic fit can be used.)

If you would like to transfer the calibration data on this page to Excel, you may copy it to the clipboard by clicking on the Copy to Clipboard... button.

Click on the Operate button the toolbar to verify the calibration. Select either Hardware verification mode or Software verification mode to verify your calibration. The Hardware mode directly reads the load values reported by the load cell based on the 'burned in' quadratic coefficients. The Software mode reads only the 'counts' value from the load cell and calculates the load on the load cell based on the selected curve fit (Two Point, Linear, Quadratic,….etc). The Hardware mode and the Software-Quadratic mode will yield the same load values.

Click Tare to zero out the load and click Start to start reading the load cells. The readings can be logged if desired. Once a load cell has been calibrated, you are ready to close the LoadVUE Calibrator program and launch LoadVUE and measure loads.

Driver Installation

Insert the iLoad Digital USB Driver CD OR the LoadVUE or LoadVUE Lite CD into your computer's drive. If you have downloaded the driver files from our web site onto a location in your hard disk, substitute that location instead of the CD drive in the instructions below. Drivers for Windows XP and Windows Vista are available here.

If you have purchased LoadVUE or LoadVUE Lite software with your iLoad Digital USB load cell, please ensure that you install the drivers as described in this document before you install the LoadVUE software. Also note that the screen shots in this document are for Windows XP, but the process is the same with Windows Vista although the appearance of screens is different.

Plug in your iLoad Digital USB load cell into an available USB port on your Windows computer. The New Hardware Wizard window will come up in a few seconds.

Select the option for "No, not this time" and click Next.

On the next screen select the option for "Install the software automatically" option and click Next. Your computer should scan the CD to find appropriate drivers for the load cell.

On the next dialog box click Continue Anyway.

Windows installs the driver for your iLoad Digital USB load cell. Click Finish.

The load cell will appear as a COM port to Windows whenever you plug it in to the same USB port on your computer. If you use a different physical USB port, you may need to go through this procedure again to associate a COM port with that USB port. However, you will usually not have to insert the CD again.

To verify the COM port number that has been assigned to the load cell, open the Hardware Device Manager. You can do so by going to the Control Panel in Windows and double-clicking on System. On the System dialog box click on the Hardware tab and select the Device Manager button.

When your iLoad Digital USB load cells is connected and correctly installed, you should see a COM port assigned to it as shown highlighted in the following screen shot (next page).

If you have more COM ports than you have load cells connected, you can double-click on the entry for a COM port. The ports associated with iLoad Digital USB load cells will indicate that they have a Loadstar Sensors driver as shown below.

You are now ready to start using your iLoad Digital USB load cell.

Hyperterminal Operation

In Windows XP, launch the Hyperterminal program.

Start...All Programs...Accessories...Communications...Hyperterminal

Set up a new connection to connect to the iLoad Digital USB load cell's COM port.

In the "Connect To" window, select the appropriate COM port.

In the "Port Settings" dialog box, accept the defaults. The baud rate is not applicable to the iLoad USB load cells.

Click OK to accept the settings. Then click "Enter" a few times. You should see the load cell respond with an "A".

Type "O0W1" and hit <Enter>. The load cell will respond with the current load on the load cell in millipounds. In the figure below the load is 2.853 pounds.

Type "CT0<Enter>" to tare the load cell. This will zero the load (all further readings will subtract the load sensed at this point.)

Type "O0W0<Enter>" to output the load continuously. Hitting <Enter> at any time will stop outputting the readings.

The iLoad Digital USB load cell can be used through LoadVUE or LoadVUE Lite software from Loadstar Sensors. It can also be used directly as a COM port using any terminal emulation software such as HyperTerminal that is included with Windows XP. To set up Hyperterminal or other terminal emulation program to communicate with the load cell, select the appropriate COM port in the program and connect. Once connected, a few simple commands are all that are needed to operate the load cell:

<Enter>	This just pings the port and the load cell responds with "A" to indicate that it is set up and ready.
CT0	This sets the tare (or zero) for the load cell. If you plan to zero out a preload, please use this command.
O0W1 O0W0	The O0W1 command outputs the weight or force reading once. O0W0 outputs a continuous stream of weight or force readings. Simply send a <carriage Enter> to stop streaming. The output is in 1/1000 of a pound (millipound). E.g., if the reading returned is 2345, the load cell reading is equivalent to 2.345 lb.
O0S2	Outputs the temperature within the load cell in deg. C. Note that this is the temperature within the load cell and is usually a few degrees higher than ambient.
SLC	This command outputs a floating point number that indicates the load capacity of the load cell in lb.
SS1	This command outputs the last three digits of the serial number of the load cell.
SS0	This command outputs the model number of the load cell.

 

Since the iLoad Digital USB Load cells present themselves to Windows as COM ports, it is very easy to write your own program to read the load cells loads. Simply open the COM port from your application and send the string O0W1<CR>. Then read the returned string back in millipounds. We recommend the following steps:

1. Open the port at 9600 (baud rate is not important), N, 8, 1.
2. Write a <CR> to the port.
3. Wait for a few milliseconds (say, 100 to 1000, this depends on your hardware, try a longer wait first then shorten it to see what works. (An alternative is to wait until there is a required number of characters in the input buffer, in this way the wait time is reduced to a minimum).
4. Read the input buffer and discard till there are no characters to read. (You can check if you get an 'A' back)
5. Write O0W1<CR> to the port,
6. Wait again for a few milliseconds.
7. Read the input buffer and process. This will contain the weight.
8. Repeat Steps 5 to 7 as needed.
9. Discard any bytes left in the input buffer before you close the port.
10. Close the port.

 

If callbacks (or events) are available, it is preferable to use them instead of polling the load cells in step 7 above. This way Windows will inform the application that there is data to be read.

Examples for Labview and Matlab are available on our support pages.