M_Logger 2.0: A Practical Modbus Master for Testing and Diagnostics
Published September 28, 2026
What M_Logger 2.0 is designed to do during PLC commissioning, Modbus testing, troubleshooting and data logging.
M_Logger 2.0 is a Windows Modbus Master / Client built around a practical engineering workflow: configure a connection, define the data you need, verify the device response, monitor values and log useful results.
Where it fits
It is useful when an engineer needs a direct way to communicate with a Modbus device without building a custom test utility for every commissioning job. The application supports Modbus RTU over serial communication and Modbus TCP over Ethernet.
Useful diagnostic tools
Read Once helps isolate a single request/response. Polling is useful when a register needs to be observed repeatedly. HEX diagnostics can expose the bytes being exchanged, which is valuable when a device appears to respond incorrectly.
From testing to logging
Once communication is working, CSV logging provides a simple way to retain monitored values for troubleshooting, commissioning records or later analysis.
See the M_Logger 2.0 product page for current licensing and download information.