RS-485 / Modbus Configuration

This is the most thoroughly documented part of the RS-485 Node's functionality, and the feature set that differentiates the node technically from simpler RS485-to-wireless converters.

At its core, the node acts as a full Modbus RTU master — meaning it initiates and manages all communication on the RS485 bus itself, actively polling connected slave devices for data rather than passively listening. A single node can manage up to 20 Modbus slave devices simultaneously, cycling through each one in turn to collect readings. This multi-device capability is significant for industrial sites where several meters or sensors share a single RS485 bus run — rather than needing one wireless node per instrument, a site can consolidate up to 20 devices behind a single RS-485 Node, considerably reducing hardware cost and installation complexity.

Register mapping is fully flexible: any Modbus register on any connected slave can be mapped to any parameter name of the operator's choosing. In practice this means a technician doesn't need to work with raw register addresses when reviewing data on the dashboard — register 40001 on a particular energy meter can simply be labelled "Active Power (kW)", making the resulting dashboard readable to non-technical staff. Each mapped register can also be assigned a specific data type — for example float32, uint16, int16, or uint32 — so that multi-register values are correctly reassembled and displayed as a single meaningful number rather than raw register fragments.

Polling behaviour is configurable per slave device rather than globally, which matters because different instruments on the same bus often need to be read at different rates — a fast-changing flow reading might need polling every few seconds, while a slowly-changing tank level might only need checking every few minutes. Every read is additionally validated using Modbus's built-in CRC (Cyclic Redundancy Check), so corrupted or incomplete reads caused by electrical noise on the bus are detected and can be discarded or retried rather than silently passed through as bad data.