What is often inaccessible for identifying a controller's firmware revision once installed?

The product label is often inaccessible for identifying a controller's firmware revision once installed because it is typically located on the exterior of the controller. In many cases, once the controller is installed in a panel or enclosure, this label may become obscured or difficult to reach. Additionally, the firmware version may change over time, and the label isn't always updated to reflect these changes, making it an unreliable source for the most current firmware information.

In contrast, the control panel, firmware update tools, and software configuration may provide direct access to the current firmware revision through their interfaces. These methods allow users to view or manage the firmware in a more accessible way, particularly during maintenance or troubleshooting, reinforcing the idea that the product label may not be the best option for identifying firmware revisions post-installation.