Gateway placement guide

The system plays a vital role in managing professional lighting networks. It is essential to maintain a proper placement of gateways to overcome the unique challenges of steel, concrete, and heavy 2.4 GHz traffic (Wi-Fi, Bluetooth, and ZigBee) found in offices and industrial infrastructure.

Network constraints and capacity

This is essential in commercial deployments to manage network size and achieve a scalable design.

Category	Description
Node limit	For a connected system, each wireless network requires one Signify Interact gateway. Each wireless network supports up to 200 nodes (Interact ready luminaires, mains powered sensors, switch relays, and Smart T-LEDs). If the lighting system exceeds this limit, deploy multiple non-overlapping networks, each with a gateway connected to the IT infrastructure.
Routers	Each node (Interact ready luminaire, mains powered sensor, switch relay, and Smart T-LED) functions as a ZigBee router when they are powered, extending the wireless mesh network.

Physical placement of gateway

Position the gateway at a central, and elevated location within the respective wireless mesh network, to optimize the line-of-sight (LoS) for all surrounding luminaires.

Mitigating signal attenuation from building materials

Professional buildings have materials that will severely attenuate to 2.4 GHz signal. Avoid positioning the gateway near these materials or relying on the signal path through these materials.

Obstruction type	Recommendation
Metal / Steel structure Example: Steel beams, HVAC ducts, metal cable trays, and industrial racking.	Maintain at least 1 metre (3 feet) separation gap from large metallic surfaces. Never mount a gateway directly on or inside a metal enclosure such as distribution box.
Thick concrete Example: Firewalls, industrial flooring, and elevator shafts.	Avoid signal penetration through more than one concrete barrier. Use a luminaire (router) immediately on the opposite side of the wall/floor to bridge the signal.
Server / Communication racks Example: Dense equipment and strong electromagnetic interference (EMI).	Position the gateway at least 3 metres (10 feet) away from any active server or network rack to avoid high EMI.
Water / Liquids Example: HVAC chillers, large pipes, and industrial tanks.	Ensure that the gateway’s installation path is clear from large bodies of water, as water is highly absorptive at 2.4 GHz.

Obstruction type

Recommendation

Metal / Steel structure
Example: Steel beams, HVAC ducts, metal cable trays, and industrial racking.

Maintain at least 1 metre (3 feet) separation gap from large metallic surfaces. Never mount a gateway directly on or inside a metal enclosure such as distribution box.

Thick concrete
Example: Firewalls, industrial flooring, and elevator shafts.

Avoid signal penetration through more than one concrete barrier. Use a luminaire (router) immediately on the opposite side of the wall/floor to bridge the signal.

Server / Communication racks
Example: Dense equipment and strong electromagnetic interference (EMI).

Position the gateway at least 3 metres (10 feet) away from any active server or network rack to avoid high EMI.

Water / Liquids
Example: HVAC chillers, large pipes, and industrial tanks.

Ensure that the gateway’s installation path is clear from large bodies of water, as water is highly absorptive at 2.4 GHz.

Critical interference management (coexistence with Wi-Fi)

The 2.4 GHz signal band is shared by both ZigBee and Wi-Fi. The channel planning is mandatory for reliable performance.

System	Recommendation
Wi-Fi 2.4 GHz	Ensure your building’s Wi-Fi network uses only the non-overlapping channels such as 1, 6, or 11 at a maximum bandwidth of 20 Mhz.
ZigBee 2.4 GHz	The gateway is configured to use the channels 11, 20 or 25 which are positioned in the spectral gaps between main Wi-Fi channels. ZigBee channel 11 is positioned at the left extremity of Wi-Fi channel 1. This generally does not interfere, unless the Wi-Fi channel 1 is constantly transmitting a large amount of data such as large file transfers.

System

Recommendation

Wi-Fi 2.4 GHz

Ensure your building’s Wi-Fi network uses only the non-overlapping channels such as 1, 6, or 11 at a maximum bandwidth of 20 Mhz.

ZigBee 2.4 GHz

The gateway is configured to use the channels 11, 20 or 25 which are positioned in the spectral gaps between main Wi-Fi channels. ZigBee channel 11 is positioned at the left extremity of Wi-Fi channel 1. This generally does not interfere, unless the Wi-Fi channel 1 is constantly transmitting a large amount of data such as large file transfers.

Maintain a minimum distance of 3 metres (10 feet) between the gateway and any high-traffic 2.4 GHz Wi-Fi Access Point (AP).

Mesh network design and commissioning

The system stability relies on a dense, and reliable mesh network of luminaires.

Mesh network requirements	Recommendation
Nodes	Each node acts as a repeater in a ZigBee mesh and should be positioned within 10 meters (33 feet) of at least two other nodes or as specified in the data sheet of the device.
Gateway connection	The gateway must be connected to an unswitched, stable power outlet, and requires an IT network connection as outlined in Network Requirements.
Deployment order	For ZigBee only devices (non-bluetooth devices), start commissioning with luminaires closest to the gateway, and expanding outwards to build a stable mesh. + Multiple networks If a group of luminaires is located too far from the main mesh network (e.g., more than 10 meters or separated by obstructive floors or walls), it is recommended to set up a new network for that group.

Mesh network requirements

Recommendation

Nodes

Each node acts as a repeater in a ZigBee mesh and should be positioned within 10 meters (33 feet) of at least two other nodes or as specified in the data sheet of the device.

Gateway connection

The gateway must be connected to an unswitched, stable power outlet, and requires an IT network connection as outlined in Network Requirements.

Deployment order

For ZigBee only devices (non-bluetooth devices), start commissioning with luminaires closest to the gateway, and expanding outwards to build a stable mesh.
+ Multiple networks
If a group of luminaires is located too far from the main mesh network (e.g., more than 10 meters or separated by obstructive floors or walls), it is recommended to set up a new network for that group.