LGH File Inspector: Open, Analyze & Export AVEVA InTouch Logs

An LGH file is a proprietary binary log file format used by AVEVA InTouch (formerly Wonderware InTouch) to store historical process data: tag values, timestamps, and quality information recorded over time by the InTouch runtime.

The challenge is that LGH files are stored in a proprietary binary format that isn't human-readable and can't be opened by standard tools like Excel, Notepad, or a database viewer. Normally, accessing the data inside an LGH file requires either running the InTouch runtime application or writing custom extraction scripts, both of which require specific software, licenses, and often significant engineering effort.

LGH File Inspector solves this by providing a purpose-built application that understands the LGH binary format, letting you open, browse, and export the data directly on any Windows workstation without any of those dependencies.

No. LGH File Inspector is a standalone application. It does not require AVEVA InTouch, the InTouch runtime, or any AVEVA software to be installed on the machine where you're analyzing the files.

This is one of the key benefits: you can copy an LGH file from a plant historian or SCADA machine, bring it to any Windows workstation in your office, and analyze it with LGH File Inspector without any additional software dependencies. This is particularly useful for engineers doing off-site analysis, incident investigators working from a laptop, or compliance teams who don't have access to the plant network.

LGH File Inspector supports LGH files generated by a broad range of AVEVA InTouch versions, including legacy Wonderware InTouch versions. It is designed to handle the LGH file formats produced by InTouch installations commonly found in production environments today.

If you have a specific InTouch version and want to confirm compatibility before purchasing, contact our technical team. We're happy to verify that your specific file format is supported. A free trial download is also available so you can test with your actual LGH files.

LGH File Inspector licenses are per user at a single location, not per computer. This means the license is tied to the individual users who will be running the application, rather than to the specific machines they use.

Practical implications:

• If multiple users will use the software on their own laptops or computers, each user needs their own license.
• If multiple users share and log into the same computer, each user who plans to use the software still needs their own license.
• If you are using Windows Terminal Services or Remote Desktop, each user who can access and use the software requires a license.

If you need more users than the 1-user or 5-user options listed, contact us for a custom quote.

Stand-Alone Application: The core LGH File Inspector opens, browses, searches, filters, and exports tag history data from LGH files to Excel and CSV. This covers the primary data analysis and reporting use cases.

Industrial Graphic Only: It has the same functionality as the stand-alone, the difference is it's just available within your InTouch Window so that a user does not need to leave the window or rely on custom scripting.

Stand-Alone + Industrial Graphic Bundle: Combines both capabilities into one license. Full tag history inspection and export, plus enhanced industrial graphic inspection and extraction. This is the "best value" option for users who need comprehensive access to all data types stored in their LGH files.

If you're unsure which edition fits your needs, reach out to our team. We can help you match the right edition to your specific use case.

Yes. LGH File Inspector is designed to work with real-world production LGH files, which can contain millions of data records spanning hours, days, or longer periods across hundreds or thousands of tags.

The search and filter capabilities are especially important for large files. Rather than trying to export everything at once, you can narrow the dataset by tag name, time range, or value threshold to get exactly the records you need before exporting. This makes working with large files practical and fast on standard engineering workstations.

If you want to test with your specific file sizes before purchasing, a free trial download is available.

Yes. A free trial download of LGH File Inspector is available from the Software Toolbox Downloads page. The trial lets you evaluate the application with your actual LGH files: open them, browse the data, and test the export workflow before committing to a purchase.

We recommend testing with a real LGH file from your environment during the evaluation to confirm compatibility and suitability for your specific use case. If you have any questions during the trial, our support team is available to help.

The 90-day subscription option is also available if you need full functionality for a limited-duration project without committing to a perpetual license.

LGH File Inspector exports historical process data to Excel (.xlsx) and CSV formats. These formats were chosen because they are the most universally useful for the common downstream uses of LGH data:

• Excel: Ready for reporting, charting, pivot tables, and sharing with stakeholders and auditors.
• CSV: Importable into virtually any analytics tool, database, historian migration utility, or BI platform.

Both formats preserve the tag name, timestamp, value, and quality information that makes the exported data meaningful for engineering analysis and compliance documentation.