Need to connect Modbus and OPC UA? The Weble WBox routes Modbus OPC UA natively: one gateway speaks both protocols and maps data points in real time — no PC, no middleware, no cloud dependency.

Modbus⇄WBoxgateway⇄OPC UAOne WBox gateway · native conversion · no PC

The protocols

Modbus

Modbus (TCP/IP and RTU) connects PLCs, meters, variable-speed drives and countless industrial devices.

Modbus driver →

OPC UA

OPC UA is the secure, platform-independent client/server standard for Industry 4.0 data exchange.

OPC UA driver →

Typical use case

Industry 4.0 and IT/OT convergence push Modbus field data up to an OPC UA layer — a SCADA, an MES or an IT analytics platform that browses and subscribes rather than polling fixed registers. The WBox brings Modbus registers into a structured, self-describing OPC UA address space, so IT systems consume the plant data with types, names and units instead of bare register numbers — and can write setpoints back through the same secure channel.

Example deployment

Typical scenario Modbus devices to an OPC UA SCADA A factory's meters, drives, inverters and small PLCs speak Modbus, but the SCADA, MES and historian above them expect OPC UA. The WBox polls the Modbus devices and republishes them as a structured OPC UA address space — named, scaled, secured — so the upper systems get a clean model instead of raw register lists. Technical documentation →

How the WBox bridges Modbus and OPC UA

Activate the Modbus and OPC UA drivers. Holding and input registers map to OPC UA nodes with the correct data type, engineering unit and scaling; clients browse the address space and subscribe to changes, so updates are event-driven. OPC UA writes propagate back to holding registers. A JavaScript step can name and group nodes, compute derived tags, or expose a clean model on top of a messy register map — all on the gateway.

Example mapping

A worked example, all on one gateway:

  • Modbus holding 40001 active power → OPC UA node ns=2;s=Plant.Meter3.Power (Float)
  • Modbus input 30005 run status → OPC UA ns=2;s=Plant.Meter3.Run (Boolean)
  • OPC UA write ns=2;s=Plant.Meter3.Setpoint → Modbus holding 40010

Capacity & limits

  • Modbus — Modbus addresses up to 247 slaves per line (RTU or TCP) — about 32 RTU devices per RS-485 segment before a repeater.
  • OPC UA — OPC UA imposes no node limit — the address space scales with the server.

On the WBox, a driver licence enables the whole protocol — there is no artificial per-point tier to unlock. Capacity scales with the gateway model, from the compact S103 to the E413: you are bounded by the field bus, not by your licence.

Frequently asked questions

How do I bring Modbus data into OPC UA?

A WBox with the Modbus and OPC UA drivers maps Modbus holding and input registers to a structured OPC UA address space — each node carries its data type, engineering unit and scaling, so IT clients browse and subscribe instead of polling raw register numbers.

Is the Modbus ⇄ OPC UA bridge bidirectional?

Yes. OPC UA writes propagate to Modbus holding registers, and register changes are published to OPC UA subscribers event-by-event.

Is the OPC UA server secure?

Yes. OPC UA brings certificate-based authentication and encrypted client/server sessions; the WBox exposes the Modbus data over that secure, platform-independent channel — the standard path for IT/OT convergence.

Do I need a SCADA gateway PC?

No. Both drivers are licence-activated on one WBox; there is no separate OPC UA server PC to maintain. A JavaScript step can name and group nodes or compute derived tags over a messy register map.

What you need

One WBox gateway with these two driver licences:

Modbus Modbus Driver licence 100.00 CHF OPC UA OPC UA Driver licence 100.00 CHF

Route Modbus OPC UA on your project

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