Here’s a general review of the based on typical industrial user feedback and technical documentation. Note that the 3RT841B is an IO-Link communication module for Siemens SIRIUS 3RT contactors, not a standalone device with user-visible firmware like a smartphone.
For 2021-era devices, firmware often corresponds to specific panel resolutions and manufacturer branding. 3rt841b firmware 2021
First, a critical clarification: The base is a size S3 or S6 contactor (depending on the exact suffix), which is an electromechanical device. It does not contain microprocessor-controlled firmware in the traditional sense. Siemens 3RT841B firmware (2021 release) Here’s a general