Vaisala WAT12, Руководство пользователя

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3.4.1 Sensor wiring
The transmitter connects to the wind sensors with the cross-arm's standard cables through 2
cable glands. WAT12 both feeds the sensor power and receives the wind data through the
cables. Plug-in type screw terminal connectors are provided both for the sensor cables and the
output line cable.
Figure 8 Wiring the sensors
1 Anemometer cable
2 Glands for power and signal cables
3 Wind vane cable
3.4.2 Signal output
The signal output provides 2 analog current loops, direction and speed, with sourcing drivers
with an o/p driving voltage 10.5 V typically and an o/p resistance of 57 W. The loops return to
the common ground for power and signal. The signal and sensor power outputs are also
current limited.
Typically, only a 4-wire shielded cable is required for the line between WAT12 and the receiving
end. Two of the 4 wires provide the operating power for the system. The other 2 are for the
current source outputs from the WAT12 transmitter; one delivering the speed signal and the
other the direction signal. The 2 readout devices are wired each across the respective current
source terminal (+) and the negative terminal of the power supply (-).
For a typical system with a 24 V DC power supply and the 5 mA signal currents, see the
following figure.
WAT12 User Guide M210309EN-B
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