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Wireless Data Communication System - WD PRO Series Instruction Manual
6. Installation
6.2.3 Distance Between Devices
Place the WDT within a 20 m radius (recommended line-of-site distance) of the WDR. If more distance is required,
add another WDT.
6.2.4 Ensuring Line of Sight
・
Good line of sight for each device (WDR, WDT) and free of any obstacles – hereafter referred to as the Fresnel
Zone – is required. The Fresnel zone is a three-dimensional space, whose size is estimated as shown in the
following illustration.
・
If you cannot establish the Fresnel zone, sometimes the available communication distance may be shorter than
usual due to obstacles inhibiting communication.
20 m
20 m
20 m
WDT
WDR
Fresnel Zone
L
D
L
D
Line of sight distance
Fresnel zone diameter
20 m
1.6 m
10 m
1.2 m
WDT
WDR
Obstacles (wall, floor, ceiling, pillar, building)
Fresnel Zone
6.2.5 WDR Installation Position and Obstacles
・
When onto a pillar such as the I-beam in a building, install the WDR in a direction that promotes the propagation of
radio waves.
・
When using the WDR in a box, use a resin box with radio wave permeability.
6.2.6.About the Signal Tower Power Supply Status
To operate this product, you need to constantly supply power to the power line. For information, refer to “7.1.4 WDB-
DB0S wiring(☞P.32)”.
CAUTION
When installing on a metal plate or concrete wall, install the devices in the Fresnel zone so they are free of any obstacles.
Figure 1
Figure 2
