SG-004A Test Tool

A browser-based Modbus test tool for the FNIRSI SG-004A, created by Bert Schuite.

The application communicates directly with the SG-004A through the Web Serial API. No installation or separate server is required.

Keywords: SG-004A, FNIRSI SG-004A, signal generator, function generator, signal calibrator, process calibrator, Modbus, Web Serial, 4-20 mA, 4-20mA, 0-10 V, 0-10V, current loop, voltage input, voltage output, tester, diagnostics and CSV logging.

Live application

Open the SG-004A Test Tool

Features

• Measure input and output values
• Automatically detect the configured input and output channels
• Set and retain output setpoints
• Function generator with sine, triangle, sawtooth, square, ramp and staircase waveforms
• Communication-aware period and points-per-cycle control
• Trend display and CSV recording
• Register overview and serial diagnostics
• English and Dutch user interface
• Simulation mode for use without connected hardware
• Responsive widescreen layout

Browser requirements

Use a current desktop version of:

• Google Chrome
• Microsoft Edge

Firefox and Safari do not currently support the Web Serial API. The browser always asks the user for permission before granting access to a serial port.

Using the test tool

1. Connect the SG-004A to the computer through USB.
2. Open the live application in Chrome or Edge.
3. Click Connect.
4. Select the serial port belonging to the SG-004A.
5. Verify the detected input type, output type and output setpoint.
6. Select the required measurement or function-generator settings.

Running locally

Download index.html and open it in Chrome or Edge. Browser security policies may differ when opening a local file, so using the published HTTPS version is recommended.

Publishing with GitHub Pages

1. Create a public GitHub repository named sg004a-testtool under the Bsc1967 account.
2. Upload all files from this directory to the repository's main branch.
3. Open the repository's Settings → Pages section.
4. Under Build and deployment, select Deploy from a branch.
5. Select the main branch and the /root directory.
6. Save the configuration and wait for GitHub Pages to finish deployment.

The application will then be available at:

https://Bsc1967.github.io/sg004a-testtool/

Safety notice

Always verify the selected signal type, output range and wiring before enabling an output. The user remains responsible for the connected equipment and all generated output values.

Privacy

The application runs entirely in the browser. It does not upload serial communication, measurements or CSV recordings to a server.

License

This project is available under the MIT License.