3 posts tagged with "Modbus"

You've successfully polled your PLC. Registers are coming back as arrays of 16-bit unsigned integers. Your Modbus transaction completed without error. Now what?

The raw register values sitting in your receive buffer are useless until you transform them into meaningful engineering units — degrees Celsius, PSI, gallons per minute, kilowatt-hours. This transformation is where a shocking number of IIoT deployments break down, producing subtly wrong data that goes unnoticed for weeks until someone realizes the chiller outlet temperature has been reading 16,384°F.

This guide covers the real-world data normalization challenges you'll face when connecting to industrial equipment, and the strategies that actually work at scale.

Modbus has been the lingua franca of industrial automation for over four decades. Despite the rise of OPC-UA, MQTT, and EtherNet/IP, Modbus remains the most widely deployed protocol on factory floors worldwide. If you're connecting PLCs, chillers, temperature controllers, or blenders to any kind of monitoring or cloud platform, you will encounter Modbus — guaranteed.

But Modbus comes in two flavors that behave very differently at the wire level: Modbus RTU (serial) and Modbus TCP (Ethernet). Choosing the wrong one — or misconfiguring either — is the single most common source of data collection failures in IIoT deployments.

This guide covers the real differences that matter when you're wiring up a plant, not textbook definitions.

Every manufacturing plant is a polyglot. Modbus RTU on the serial bus. Modbus TCP on the local network. EtherNet/IP talking to Allen-Bradley PLCs. And now someone wants all of that data in the cloud via MQTT.

Protocol bridging at the edge is the unglamorous but critical work that makes IIoT actually function. Get it right, and you have a seamless data pipeline from a 20-year-old Modbus RTU device to a modern cloud analytics platform. Get it wrong, and you have data gaps, crashed connections, and a plant floor that's lost trust in your "smart factory" initiative.

This guide covers the architecture, pitfalls, and hard-won lessons from building protocol bridges that run in production — not just in proof-of-concepts.