54
Up to 4
sensors
PM2.5 / 10 sensor
3.3
RECOMMENDATION FOR BEST WIRELESS COMMUNICATION
Effective wireless communication is susceptible to noise interference in the environment, and
distance and barriers between the sensor transmitter and the display console.
1. Electromagnetic interference (EMI) – these may be generated by machinery, appliances,
lighting, dimmers and computers, etc. So please keep your display console 1 or 2 meters
away from these items.
2. Radio-frequency interference (RFI) – if you have other devices operating on 868 MHz, you
might experience communication intermittent. Please re-located your transmitter or display
console to avoid signal intermittent problem.
3. Distance. Path loss occurs naturally with distance. This device is rated to 150m (450 feet)
by line of sight (in interference free environment and without barriers). However, typically
you will get 30m (100 feet) maximum in real life installation, which includes passing through
barriers.
4. Barriers. Radio signal are blocked by metal barriers such as aluminum cladding. Please align
the sensor array and display console to get them in clear line of sight through window if you
have metal cladding.
The table below show a typical level of reduction in signal strength each time the signal passed
through these building materials
Materials
Signal strength reduction
Glass (untreated)
10 ~ 20%
Wood
10 ~ 30%
Plasterboard / drywall
20 ~ 40%
Brick
30 ~ 50%
Foil insulation
60 ~ 70%
Concrete wall
80 ~ 90%
Aluminum siding
100%
Metal wall
100%
Remarks: RF signal reduction for reference
Содержание 4Cast PRO SF
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