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BAS-SVX40K-EN
Pre-Installation
Designing an Air-Fi® wireless system with robust performance and reliability is relatively easy. However,
the design of a wireless network has a direct impact on performance and reliability. For example,
performance can be improved by locating the coordinator near the center of the network. Reliability can
be enhanced by avoiding wireless signal obstructions.
Note:
Always check for pre-existing Air-Fi networks using Tracer TU and the Wireless Adapter. If a
network already exists you won’t be allowed to create another network using the same address.
Location Considerations
For most installations, barriers limit proper radio signal quality more than distance. To provide the best
signal quality between wireless devices and to reduce the number of WCIs needed for an application,
mount WCIs and WCSs in direct, unobstructed, line-of-sight paths. Where this is not possible, try to
minimize the number of barriers between a WCI and a WCS or coordinator. In general, sheetrock
(drywall) walls and ceiling tiles offer little range reduction to the transmission of the radio signal
throughout the building. Do not design networks to span more than one floor.
For more detailed information about WCI placement, see the
Air-Fi® Network Design Installation,
Operation, and Maintenance manual
(BAS-SVX55*-EN).
WCI Positioning
It makes no difference whether the WCI is positioned horizontally or vertically. It will work in any position.
However it is good to know that the antenna is located within the top 1” of the WCI. The antenna
radiates in all directions, generally in the shape of a sphere. The position of the WCI, either horizontal or
vertical, does not change the radiation pattern. However, the surface where the WCI is mounted can
change the radiation pattern. If mounted to a sheet metal box like on a VAV, the sheet metal will reflect
much of the radiated signal, in effect blocking the signal from going to the other side of the VAV box.
Once the radio signal leaves the antenna it bounces around off hard surfaces in all directions which
tends to alleviate some of the blocking effects of the sheet metal box. Most of the time this blocking
effect will not be a concern because the bouncing radio signals tend to fill in the entire area. However, in
cases where too much signal level is blocked by a sheet metal box or object, and there is not enough
signal bouncing back, it may be necessary to reposition the WCI or insure at least the top 1” of the WCI
is cleared of any metal objects so the radio signal is free to radiate in the direction it needs to go.
Line of Sight Placement
When mounting WCIs, always be cognizant of where the coordinator and other WCIs are located. You
do not need to physically see the coordinator or other WCIs from each WCI, but you should at least be
aware of any obstruction between them. Remember that the radio signal will penetrate three (3) drywall
walls or one cinder block wall and still have about 200 feet of range, so these obstructions should not
cause concern. An obstruction like large duct work, sheet metal boxes, large steel electrical panels,
solid concrete walls or elevator shafts may cause signal degradation. If you encounter these
obstructions you can extend the IMC cable and mount the WCI in a better location that will give a better
“line of sight” placement around the obstruction creating an unobstructed signal path to the coordinator
or other WCIs.
The IMC and power cable can be extended up to 656 feet using methods described in
WCI Maximum Wire Length
The maximum wire length between the WCI and its power / communication source is 656 ft (200 m).
Note:
The connector that comes with the WCI is one meter in length.
WCI Installation Locations
Note:
To comply with FCC regulations, do not mount this WCI within 20 cm (8 inches) of any other radio
device including other WCI or wireless sensors. or other wireless devices.
