Modbus Read/Write Multiple registers

Issue

What is the maximum number of registers that can be read/written using the multiple read/write function codes in Modbus

Product Line

SmartStruxure Solution

Environment

StruxureWare Building Operation

Modbus

Cause

When deciding how to group registers using a Modbus Register Group, it is important to know the maximum number of registers that can be grouped.

Resolution

Read multiple registers = maximum 125 registers

Write multiple registers = maximum 121 registers