Free BMS commissioning tool

Modbus value conversion made easier for BMS engineers.

A simple browser-based tool to help check Modbus register values, signed and unsigned equivalents, hex values, high/low bytes and common byte order issues during commissioning. Save it locally and use it offline on site once downloaded.

Get the free tool
Screenshot of the Modbus tool showing the register address calculator and calculated outputs

Built for real commissioning work

This tool is intended for engineers working with BMS integrations, Modbus meters, controllers, gateways and third-party equipment where manually entered register values need to be checked, converted or broken down into individual bit states.

01

Convert user-entered Modbus values

Enter values from a register list, BMS point, gateway or commissioning result and convert them into useful formats. The tool does not connect to devices or read live registers.

02

Turn analogue values into binary bits

Type in a 16-bit analogue/register value and see the individual bit states, signed equivalent, unsigned value, hex value and high/low bytes.

03

Turn binary bits back into a value

Set individual bit states and calculate the resulting analogue/register value. Useful for visualising packed fault, alarm and status bits during Modbus commissioning.

What the tool looks like

These previews are taken directly from the downloadable HTML tool, so when you open it on site it should look familiar from the training videos and from this page.

Register Address Decoder tab showing hex to decimal and Modbus address conversion

Register address decoder

Quickly convert between Hex, Decimal / JBus and traditional Modbus / Modicon addresses.

16-bit Value to Bits tab showing decoded bit states from a register value

16-bit value to bits

Decode a register value into its signed equivalent, hex value, high/low bytes and individual bit states.

16-bit Bits to Value tab showing bit toggles and calculated register output

16-bit bits to value

Build a register value from individual bits when you need to prove packed status or alarm values.

32-bit Word and Byte Order tab showing Float32 value, register words and byte sequence

32-bit word/byte order

Visualise how two 16-bit registers combine into one 32-bit value, including word and byte order changes.

Demonstration videos

Watch the tool being used on YouTube

I’ll be adding demonstration videos showing how to use the Modbus tool during real BMS commissioning scenarios, including register address checks, signed/unsigned values, byte order issues and bit status visualisation.

Watch on YouTube