OHAUS Ranger 3000 Scale

How to use the Ranger 3000 scale with a computer to collect data

To connect the scale to the computer, you will first need a USB to RS232 serial cable. Currently (8/9/21), we have two such cables in the lab that should be stored with the scale.

A USB to serial cable

The cable mounts to a serial connector on the underside of the scale below the red cover.

Once you have the cable, you will need to download some program to read from the serial cable. This tutorial will cover the use of the program suite Windmill ComDebug.

Download ComDebug here, then run the setup.exe file after extracting the folder.

From here, I will cover the needed steps for the different programs installed as part of ComDebug.

ComDebug

The start screen for ComDebug

This program will set up the actual communication through the COM port. To begin, click on the button next to "Create a new Windmill Instrument File". Select "Serial Communications" to get into the "COM Port Settings" window.

Here, define the COM Port as whatever the USB to serial cable is assigned to in the Device Manager. The rest of the settings are defined to match the settings of the scale.

To access/change these settings on the scale, follow these steps:

1. With the scale turned on, press and hold the "Menu" button.

2. Keep pressing the "Print" button until "COM" is displayed on the screen, then press "On/Zero".

3. Use the "Print" button to cycle to the various settings, then "On/Zero" to enter the menus.

Page EN-21 in the Ranger 3000 manual covers the COM menu for more detail.

If changing the Baud Rate, you also need to change the properties of the port in the Device Manager. To do so, follow these steps:

1. Right click on the port and select "Properties"

2. Under "Port Settings", change the "Bits per second" property to the Baud Rate you have set

The settings I have been using to take data from the scale.

Once you have changed all of these settings, press "OK" to continue. This will take you to the Main Menu of comDebug.

comDebug Main Menu

If at any point you want to edit these settings again, simply press "Edit COM Port Settings".

The following tabs lay out the settings that need to be changed from this menu.

Editing data channels

Press "Edit the data channel details" to define what variable(s) you want to store data under. In this case, we will be defining a Weight variable to store the value from the scale. I defined the different parameters as follows:

Channel details for reading off of the scale

If there isn't anything in the Msg category yet, don't worry; we'll define that shortly. Once you are done defining the channel, exit out of the window.

Editing instrument timings

Press "Edit the Instrument Timings" to define the timings of how the program will get data. I've found that you really only need to change the "Data Persistence Time" to ensure that the program records changes at a decent time scale.

Settings to ensure speedy data update

Editing message

Press "Edit Message_1" to edit the commands that the program sends to the scale. Name the message whatever you want here. First, define the Prompt values as follows:

Prompt settings for the scale

To check if this is working correctly, press "Send" below the Prompt column. You should see a weight reading appear in the Reply column.

Next, press the "Parse" button to change how the program parses the data for display. These are the settings I have used to parse the weight:

Reply parser settings for the scale

If you're using other settings, you can check what each step is doing by clicking on the "Step" menu item while highlighting one of the steps. The sections of the reply that are being parsed by that step will highlight in green in the Message Edit window, as below.

The portions of the reply parsed by Step 1 in the parser menu.

To define the extracting step, click on the "Extract" menu item. It will then allow you to tie the data channel as the output of the message commands.

Pressing the "Close" button or exiting out of the window will set these settings.

Once all of these settings are defined, go back into the "Edit Message" menu to check if everything is working correctly. From this menu, press the "Run" button to open the "Display Screen" menu.

The Display Screen upon first opening

From here, set the "Sample Rate" as the value you set the "Data Persistence Time" value to before (in this case 50 ms = 0.05 s), then press "Start" to start displaying real-time data from the scale.

Once everything is working correctly, go back to the Main Menu and press "Save .IMD File" to save this setup. In the future, you can then open this setup again in ComDebug by selecting "Edit an existing Windmill Instrument File" in the start screen.

SetupIML

To use the other programs included with ComDebug, you also need to set up a .IML file. ComDebug only sets up a .IMD file.

When opening SetupIML, choose to "Create new setup" from the menu that opens. Choose whatever name you'd like (I chose RANGER) and press "OK".

The main menu of SetupIML

The .IMD setup you configured in ComDebug should show up here. Then, just save the file and exit the application.

Windmill Logger

The logger allows you to display the readings off the scale in real time through the computer. Upon opening Logger, select "File > Load Hardware Setup". Locate where you saved the .IML file from earlier. The default location should be "C:\Program Files (x86)\Windmill Software\Windmill\SetUps".

Upon opening the hardware file, you will then choose which channels to connect to the logger. Find the channel you defined in ComDebug and move it over to "Connected Channels". You can change the connected channels at any time via the "Inputs" menu item.

Connecting channels to the Logger

From here, the top menu items change the logger in the following ways:

Settings

The settings window of the logger

The settings window allows you to change the input read time, as well as how it displays the time stamps.

File Options

File options for the logger

The File Options menu allows you to change when/how the logger puts data into files.

I haven't gotten the files that the logger saves to actually show up in the Data folder, so I generally just have the logger not save data to a file in the File Options window.

Troubleshooting

Can't connect to the COM port when opening program.

This is likely because another one of the Windmill programs is using the COM port. To fix this, close all Windmill programs, including the IML Devices that will only show up on the Taskbar.

The devices on the taskbar that also need to be closed.

Other Resources

Ranger 3000 Manual Capturing Data from an Ohaus Balance