Modbus Test Utility - Free alternative to Modscan / Modbus Poll / Simply Modbus

Modbus Test Tool / Modbus Master Simulator

Modbus test utilities are used to diagnose Modbus communication and verifying the data in specific address. The utility is used for testing Modbus slave device.

What a Modbus Test Utility Can do (Application / Features)?

Modbus test utility can connect to your Modbus device and verify the communication is established. Modbus test utility is used to test and debug slave devices. Read value from slave device. Write value to slave device. Log data. View communication traffic.

Top Free Modbus Utilities

  • Radzio! Modbus Master Simulator

This Modbus utility is a freeware. This tool can be used as an alternative to Modscan, Modbus Poll,Simplymodbus

The utility allows to communicate with multiple slave devices.

Radizo tool is very user friendly and reliable.

Supported Protocol – Modbus RTU / Modbus TCP.

Platform – Windows.

Download Link - Modbus Master Simulator - free software utility for testing Modbus slave devices

  • Modbus Tester by Schneider electric.

Modbus Tester is a freeware. Modbus tester is a simple utility which allows to read from a register and write to a register of a Modbus slave device.

How to use Modbus tester?

To connect to a Modbus TCP/IP Slave device select port as TCP/IP and enter ip address.

Select COM port and enter parity/baud rate for connecting to a Modbus ASCII/MODBUS RTU device.

Enter the slave address and select the data type.

Enter the register address. Now you can read/write values.

Supporting Protocol – Modbus TCP/IP,Modbus RTU,Modbus ASCII,Jbus.

Platform – Windows

Download Link - Video: What is Modbus Tester and how do I use it? | Schneider Electric USA

  • QModeMaster

Qmodemaster supports Modbus RTU and Modbus TCP protocol.

This utility allows an easy communication with Modbus RTU and Modbus slave devices.

QmodeMaster supports windows and linux operating system.

This software can monitor the Modbus traffic also.

QModemaster is an open source free software.

<img src=“//” width=“500” height=“332” “Modscan alternative”>

Download link - QModMaster download |

  • Modpoll Modbus® Polling Tool

This utility is command line based.

Modpoll supports following operating systems Windows,Linux,Solaris,QNX 6.

Modpoll is a free Modbus master simulator.

Download Link - Free Modbus Master Simulator and Test Tool

1 Like

regarding the Schneider test program:

No floating point (real) or 32 bit long integer value interpretations.

From the single shot screen view, note that the tester will read multiple registers, but displays only single register data as decimal or hex. Hence, it appears not to display an interpretation of any 32 bit floating point (real) value (in any word/byte format), nor 32 bit long integer value.

But it’s only a free test program. The balloon explanations are well done.