Using the Load Cell

Use this set of instructions when working with the load cell and PanelX software.

Download the software from the HBM web page.

Connecting the load cell to PanelX

Connect the USB cable to a Windows computer.
Turn on the power supply and wait a few seconds.
Start the PanelX program; a Device scan window will open automatically. If the device was connected before, no scanning is necessary again. You must, however, check if the baud rate is set to 34800. If it is not, follow the next steps.
Select the RS232/RS485 option and the proper COM port. To see which COM port the load cell is using, go to the “Computer” icon in your Desktop and find the device. Right click on the device and select Properties. In the properties window, the COM port should appear. Normally, the load cell connects to COM 3 in the HP ProBook.
Select the baud rate at which you want to work with (34800 is recommended for dynamic weighing).
Click SCAN. The number and the sensor information will appear.
If the number of devices is zero, then you must perform the scan again or check if there are any problems with the connections of the load cell.
Close the window by clicking OK.
Your display should look something like this.

Begin Working with PanelX

Go to the top menu and click on Options.
On the Options menu go to User level.
Select the Administrator user level so that all the menu items are available.

Application:

Go to the Application tab.
Select Checkweigher. This is used in industrial applications and I didn’t notice any change in the measurements when using standard or checkweigher. Use the one you like.

Adjustments:

Before working with the load cell, certain adjustments are necessary.

Click on the Adjustment menu icon:
Select the decimal point configuration to: *******. This setting will display a number in this form: XX.

To make it have one decimal point, click on the x10 icon.

A number in this form should appear on the measurement window: XX.X
Choose the measuring units. (i.e. “g” ).
In this decimal configuration, the highest resolution is of 1g. Select this option.
Set the nominal value to 20000 g. This is supposed to be the range of the measurement you are having, however the load cell only displays correct data when the nominal value is: 20000 g.

Your configuration should look like this:
Click on Write.

Using Scope

The scope tab lets you see the measurements that you are taking and graphs them through time. We will set the scope measurement to the Standard analysis.

Click on the scope tab.
On the Mode drop down menu, select the Standard option. This will plot the values measured vs. time.
On the time window, select how much time you want displayed on the chart. (i.e. 1 min time window). Even though you choose a 1 min time window, the load cell won’t stop measuring unless you click STOP.
On the scope window, Go to chart and click on Auto vertical zoom. In this configuration, the zoom adjusts to the values you are measuring.
If desired, you can also set a range and a fixed zoom.
Before you start measuring, make sure the measurement display is showing a correct value. In order to set the measurement display to zero, click on the TARE button.
Once you have setup everything and are ready to measure, click the Start button to start measurements.
When you are finished taking measurements, click on the STOP button to stop recording data.

Observations

Notice how the time window shifts to the right as the time you had specified in the time window is surpassed. If you want to copy the chart picture, click on: COPY CHART. This will take a picture of the chart that is displayed at that moment and allows you to paste it on a document.

More on the Scope Window

In the scope area, after performing the number of measurements in the time interval you had set up on the time window, the program performs certain statistical operations on the data read by the device. It will display max and min values, as well as the average measurement and the standard deviation of your data.

The Cursor tool

The cursor tool, allows you to perform data analysis as the one described above, but the data analyzed is going to be the interval you select with the cursor.
Click on the cursor tool to enable it and select the interval you want to analyze.
Information of that time interval will appear on the screen.

Observations of the scope measurement graph:

In the measurement display, you see a number in the form of XX.X if you clicked on the x10 button. So, in the scope data, even though the measurement display shows a value with a decimal point, the graph eliminates this decimal point and will show a number in this format: XXX.
For example, if your measurement is 57.1, the scope data will display a value of: 571 g, so the recommended thing is to try a known measured quantity and familiarize with how the scope window shows the data measured.

Saving the scope data:

On the file drop down menu on the top left corner, click on Save Scope data, this will create a CSV file with time and measurement.

Filters

Filters are used to cut off certain frequencies and prevent from displaying noise.
The filters used for dynamic weighing are the FMD1, FMD3, FMD4, and FMD5 filters.

Go to the filters tab.
Select the filter that most suits you.
Recommended settings:
Click on WRITE.

More on filters:
The 3rd filter : IIR4 (fast track) provided stable values with little noise. Almost constant lines with a 0.1 variation. Be careful when setting the cutoff frequency, because if you choose a small cutoff frequency, you lower the sensitivity of the load cell to change. You will obtain a slow reaction time if cutoff frequency is 0.1 Hz. Try using 1.5 Hz, this will give faster reaction times. If you don’t observe changes in your experiments, then try elevating the cutoff frequency so that the load cell becomes more sensitive to change.
You might want to play with filters and their cutoff frequency to see which one suits the most to your experiment, just take into account which filters are the ones recommended for dynamic weighing and the effect of elevating or reducing cutoff frequencies.

Resetting to Factory Settings

If you need to restore factory settings, you must open the AED Panel_32 program on the computer. A description of how to open this software is here.

Once you have all setup, follow these steps.

In order to reset to factory settings, we must issue a command via the command line of the program.
Go to the COMMANDER TAB.
Write the following command and press enter: TDD0.
Once this is done, you must perform again the configuration as described in this wiki. Perform a series of measurements with known quantities to make sure the load cell is working properly.