What Is a Silvair Bluetooth Mesh Network in 2026?
Silvair’s current wireless lighting-control solution is based on Bluetooth NLC. Bluetooth NLC uses Bluetooth LE at the radio layer and Bluetooth Mesh at the communication layer, then adds standardized lighting device profiles for luminaires, occupancy and ambient-light sensors, switches, dimming controls, and energy monitoring. A Silvair Bluetooth Mesh network therefore still needs disciplined radio and traffic planning even when the application layer is described as Bluetooth NLC. [6]
Bluetooth Mesh normally propagates messages through managed flooding rather than fixed-path routing. Relay planning determines where messages can be rebroadcast efficiently; it does not create one permanent route from a source to a destination. The practical design objective is redundant radio reachability with controlled retransmission traffic. [6]
How Are Project, Area, Zone, Relay, Proxy, and Gateway Different?
One Project is one independent Bluetooth Mesh network. A Project can contain multiple Areas, and those Areas remain part of the same network and must support Area-to-Area communication. Areas are logical traffic and management partitions used to improve performance and simplify commissioning. If an Area cannot communicate with the other Areas in the Project at all, it should be treated as a separate Project rather than as an isolated subdivision. A Zone exists inside an Area and defines the control behavior of luminaires, sensors, and switches. Zone linking is limited to Zones in the same Area. [3]
| Object | What it solves | Planning implication |
| Project | One independent mesh network | Set a boundary only where the installation can operate as one network. |
| Area | Traffic, performance, and management partition | Keep Area-to-Area communication viable; design around ~200 devices. |
| Zone | Lighting-control behavior | Keep linked Zones within one Area. |
| Relay | Rebroadcasts mesh messages | Place for retransmission coverage, not as a fixed route. |
| Proxy | Connects a GATT client such as a phone | Supports commissioning and management access. |
| Gateway | Connects commissioned local mesh to Silvair Cloud | Required for selected connected services, not basic local control. |
How Should Large Projects Be Divided into Areas and Zones?
Silvair recommends dividing large projects so that each Area contains no more than approximately 200 devices. This is a system-design recommendation, not a Bluetooth protocol hard limit. A simple installation may sometimes exceed it, but device type, sensor publishing frequency, control scenarios, topology, construction materials, and Replay Protection List (RPL) consumption can change the result. Do not treat an over-200 Area as the standard design choice. [1]
For practical scaling, Silvair examples divide 300 devices into two Areas of roughly 150, 400 devices into two Areas of roughly 200, and 600 devices into three Areas of roughly 200 or four Areas of roughly 150. Keep Zones aligned to lighting behavior, then check their control relationships and traffic implications before commissioning. This is the core of Silvair network planning for a large site. [1]
How Does the Replay Protection List Affect Large Silvair Projects?
The RPL records received message sources and sequence numbers to protect a device against replay attacks. Its capacity also limits how many distinct message sources a device can receive and process. Zone membership, linked Zones, sensors, switches, Relays, and mobile devices used during commissioning can all consume RPL slots. Once the RPL is full, a device may be unable to accept messages from new sources. [1]
Silvair SN-213 Rev. 3.3 lists 126 RPL slots for Firmware 2.13 and earlier, 255 for Firmware 2.14–2.17, and 350 for Firmware 2.18 and later. In the document’s example conditions—Firmware 2.18+, about 10% Relays, and two commissioning mobile devices—a daylight-harvesting Zone without Zone linking can contain about 160 sensor-controller devices. Linking two similar Zones reduces the example to about 100 devices. These are scenario-specific planning examples, not universal capacities. Silvair also advises against using Zone linking to make one Zone accept manual control from more than 28 Zones. [1]
What Range and Topology Rules Should Guide Device Placement?
There is no universal Bluetooth mesh lighting range for a finished project. Controller and antenna design, transmitter power, fixture housing, mounting orientation, walls, ceilings, steel racking, machinery, inventory, and nearby RF activity all matter. Verify the range using the actual controller, driver, sensor, and complete luminaire in representative installed conditions; then retain a margin. For example, if a test shows 11 m, planning for 10 m is more robust than using the measured limit. [2]
Silvair treats device distances above approximately 60% of verified radio range as one condition that makes a project complex. It is not a maximum allowed spacing and does not mean a link must fail above 60%; it is a trigger for more conservative topology, Relay, and coverage checks. In the Silvair app, use the Add Device view to observe device availability and the Test workflow to verify that a second device responds through the first under representative conditions. [2]
Make two-neighbor reachability the default target
As a general topology target, each device should be within direct radio range of at least two other devices. Dense office grids and regular production areas often achieve this naturally. A Bluetooth mesh lighting network design for a corridor, tunnel, conveyor line, long aisle, outdoor site, or sparse high-bay layout may not; those installations need conservative spacing, deliberate Relay placement, smaller Zones, and stricter site verification. [1][2]
Plan for final operating conditions
An industrial Bluetooth Mesh network should be tested after metal racks, cabinets, equipment, partitions, doors, and inventory are in place. The radio result from an empty construction shell or an open-air bench test may not represent the operating facility. Record housing material, antenna location, fixture orientation, installation height, and obstacle locations as part of the network evidence. [2]
How Should Relays Be Selected and Adjusted?
When devices join a Zone, Silvair normally assigns Relay functionality randomly to approximately 10% of them. That default can work in a dense, regular grid, but it does not account for physical location. Treat it as a baseline, not a final Relay map. In dense layouts, adding Relays blindly can increase message volume, interference, and congestion. [1][2]
In sparse, outdoor, and linear installations, the automatic ~10% selection is often insufficient. Identify weak transitions, long gaps, obstructed points, and single-chain sections; then manually select and distribute Relays along the physical layout. Very sparse designs may require many—or in exceptional cases all suitable—devices to relay, but only site testing can justify that decision. Smaller Zones are also a Silvair network-optimization measure for linear projects because they help limit the impact of limited redundant reachability. [2]
When Is a Gateway Needed, and What Can It Serve?
A Gateway is not required for basic local lighting control. A Relay rebroadcasts mesh messages, a Proxy lets a GATT client such as a phone access the mesh for management, and a Gateway connects a commissioned local network to Silvair Cloud for services such as scheduling, remote functions, and selected monitoring. [3][5]
One Silvair Gateway can schedule events across multiple Areas. For energy and occupancy monitoring, Silvair recommends approximately 200 mesh devices in total across all served Areas; exceeding that number may result in inaccurate reporting. More than 200 devices can be scheduled, provided each individual Area remains at approximately 200 devices or fewer. The Gateway must have a direct connection to at least one device in every controlled Area. Position it for strong direct radio access, away from avoidable interference and shielding construction. [1][5]
What Information Is Required Before Network Planning?
- Controller, driver, sensor, and Gateway models, plus installed firmware versions.
- Luminaire housing material, antenna position, mounting orientation, height, and fixture spacing.
- Walls, ceilings, metal racking, machinery, lift shafts, ducts, electrical cabinets, and likely RF sources.
- Area and Zone count, Zone-linking relationships, Control Profiles, and expected sensor publishing frequency.
- Required Gateway services, practical tested range with margin, proposed Relay locations, and RPL considerations.
This input converts a generic large Bluetooth Mesh lighting system concept into a buildable plan. It also gives the commissioning team a traceable basis for acceptance tests.
How Should Each Area Be Tested Before Handover?
First validate representative sections with the real installed equipment, especially in warehouses, factories, parking structures, tunnels, and outdoor sites. Then commission each Area, verify the intended Relay arrangement, and run a Mesh Quality Test separately for every Area. After any material Relay change, rerun the test and continue functional checks for switching, dimming, scenes, and sensor behavior. [2][4]
Silvair guidance requires a 100% Mesh Quality Test result: all Zones must appear green in the Silvair mobile app. This is the application’s commissioning pass criterion, not a statement that radio signal strength or packet delivery is always 100%. If a device or Zone is red, inspect distance, antenna orientation, obstacles, interference sources, and Relay placement, then correct and retest. [4]
How Should the Design Record Be Used?
At concept stage, a Silvair Bluetooth Mesh network record should state the Project boundary, Areas, Zones, device count, and intended control functions. Silvair network planning should also identify the Bluetooth mesh lighting network design assumptions, the verified Bluetooth mesh lighting range, the expected Silvair network range margin, and the Relay positions for a large Bluetooth Mesh lighting system in its actual installation environment. For an industrial Bluetooth Mesh network, the record should explicitly show metal obstructions and final operating conditions.
Before commissioning, the Silvair Bluetooth Mesh network record should be updated with firmware versions, RPL assumptions, linked-Zone relationships, proxy access, and Gateway services. The Bluetooth mesh lighting network design should then be tested against the practical Bluetooth mesh lighting range and the Silvair network range observed with the installed luminaire. A large Bluetooth Mesh lighting system requires these evidence-based checks; an industrial Bluetooth Mesh network also requires a final-condition retest. This step is a central part of Silvair network planning.
During acceptance, the Silvair Bluetooth Mesh network test record should identify the Area tested, Relay changes, red Zones or devices, corrective action, functional tests, and final Mesh Quality result. Use the same Bluetooth mesh lighting network design record to confirm that the Bluetooth mesh lighting range margin was preserved and that the Silvair network range was not assumed from an open-air value. This approach helps a large Bluetooth Mesh lighting system remain maintainable after handover and gives an industrial Bluetooth Mesh network a defensible verification history.
For later changes, the Silvair Bluetooth Mesh network owner should review the documented topology before moving fixtures, adding sensors, changing Zone links, or introducing new obstructions. A Silvair Bluetooth Mesh network should be retested by Area after a material change, and the Silvair network range should be revalidated whenever the physical environment changes.
Conclusion
Reliable Silvair network planning is a physical and operational discipline. Keep Areas at approximately 200 devices or fewer, plan RPL consumption before dense sensor and linked-Zone scenarios, test the actual installed radio environment, and use Relays to provide balanced retransmission coverage rather than presumed fixed paths. A Silvair Bluetooth Mesh network is ready for handover only when every Area has verified connectivity, correct functional behavior, and a 100% Mesh Quality Test result. A Silvair Bluetooth Mesh network should retain documented test evidence for future changes. A Silvair Bluetooth Mesh network also remains more resilient when its final physical topology preserves practical radio margin and redundant neighbor reachability.
FAQ
How many devices can a Silvair Project contain?
A Project can scale to thousands of devices, but it should be divided into communication-capable Areas. Silvair planning material describes projects in the approximately 8,000–10,000-device range; this does not make one Area suitable for that many devices. [1]
How many devices should be placed in one Silvair Area?
Silvair recommends approximately 200 devices or fewer per Area as the normal system-design approach. It is not a Bluetooth protocol hard limit, but going beyond it requires careful analysis of traffic, topology, firmware, and RPL use. [1]
Is 200 devices a hard Bluetooth Mesh limit?
No. It is a Silvair system-design recommendation. A simple Area may sometimes operate above it, but that outcome should not replace a conservative Area design. [1]
Can Zones in different Areas be linked?
No. Zone linking is limited to Zones within the same Area. Keep the control relationship and its RPL impact inside the relevant Area. [1][3]
Can Relays in one Area retransmit traffic for another Area?
No. Areas remain connected within one Project, but normal Area-level Relay behavior is not a remedy for poor connectivity in another Area. Design the Area boundaries and radio coverage correctly. [1]
Why does the Replay Protection List matter?
RPL capacity limits the number of distinct message sources a device can process. Sensors, linked Zones, Relays, and commissioning phones can consume slots, so RPL must be assessed in complex Areas. [1]
How many Relays should a dense network use?
The default random assignment is about 10% when devices join a Zone, and dense grids may need no more than that. Validate the actual topology; more Relays can add unnecessary traffic. [1][2]
Why do linear installations need manual Relay placement?
A line has fewer alternate radio paths. Manual Relay placement, smaller Zones, conservative spacing, and representative testing reduce the risk that one weak section interrupts message propagation. [2]
What does a 100% Mesh Quality Test result mean?
It means all Zones in the tested Area are green in the Silvair mobile app. It is the commissioning pass criterion, not a literal guarantee of 100% RF signal or packet delivery. [4]
Does every Silvair Area require a Gateway?
No. Basic local lighting control works without one. A Gateway is needed only for selected cloud-connected services such as scheduling, remote functions, or relevant monitoring. [5]
How many devices can one Gateway monitor?
For energy and occupancy monitoring, Silvair recommends approximately 200 mesh devices in total across the Areas served by that Gateway. Scheduling may cover more, provided each Area remains at approximately 200 devices or fewer. [1][5]
How should practical Bluetooth mesh range be tested?
Test real devices in their final or representative fixtures and mounting conditions, observe availability in the app, verify control through a neighboring device, and retain a distance margin instead of designing at the measured maximum. [2]
Technical References
- Silvair, SN-213: Recommendations for Complex Lighting Installations, Rev. 3.3.
- Silvair, SN-202: Optimizing Mesh Network Performance, Rev. 7.1.
- Silvair, SN-230: Commissioning Quick Start Guide.
- Silvair Support: Troubleshooting and Mesh Quality guidance.
- Silvair Gateway User Guide.
- Bluetooth SIG and Silvair Bluetooth NLC resources.
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