Need to connect Saia S-Bus and MQTT? The Weble WBox routes Saia S-Bus MQTT natively: one gateway speaks both protocols and maps data points in real time — no PC, no middleware, no cloud dependency.
The protocols
Saia S-Bus
Ether S-Bus is the native protocol of Saia-Burgess PCD controllers (SBC), widespread in Swiss buildings — reading and writing registers, flags, inputs and outputs.
Saia S-Bus driver →MQTT
MQTT is the lightweight publish/subscribe protocol used by IoT devices and cloud brokers.
MQTT driver →Typical use case
Dozens of heating substations or technical rooms run on Saia PCDs, and operations wants them all on one cloud dashboard. The WBox reads each PCD over S-Bus and publishes the values to an MQTT broker: energy data, temperatures and fault flags from every site arrive on structured topics — without touching the PG5 programs or opening the sites' networks.
Example deployment
How the WBox bridges Saia S-Bus and MQTT
The S-Bus driver polls registers and flags from the PCD stations over UDP 5050 on a configurable cycle. Values are scaled on the gateway and published as JSON to your MQTT topics, with TLS to the broker and QoS per topic. Commands can flow back too — a subscribed topic writes a PCD register — or the link stays publish-only if operations prefers read-only supervision.
Capacity & limits
- Saia S-Bus — Ether S-Bus runs over UDP/IP — one connection per Saia PCD (station 0–255), reading and writing registers, flags, inputs and outputs; address lists import directly from PG5.
- MQTT — MQTT imposes no point limit — topics scale with your broker and network.
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 connect Saia S-Bus and MQTT?
Saia S-Bus is the Saia PCD controller protocol (Ether S-Bus) and MQTT is the lightweight IoT publish/subscribe protocol. A single WBox gateway runs the Saia S-Bus and MQTT drivers, speaks both protocols at once and maps the data points between them — no PC, no middleware, no cloud dependency.
Is the Saia S-Bus ⇄ MQTT bridge bidirectional?
Yes. The WBox reads and writes on both sides: a value or command on the Saia S-Bus side propagates to MQTT, and vice-versa.
Do I need a PC, a PLC or proprietary hardware?
No. The Saia S-Bus and MQTT drivers are licence-activated on one WBox — no gateway PC, no intermediate PLC and no proprietary hardware.
Which WBox model do I need?
Any WBox with the Saia S-Bus and MQTT driver licences. The online configurator recommends the right model from your interfaces and point count.
What you need
One WBox gateway with these two driver licences:
Route Saia S-Bus MQTT on your project
Find the right WBox gateway for your installation, or get in touch to validate your case.
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