Comptus A70-SDL Series, Инструкция по эксплуатации

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16
WIND DIRECTION TRANSMITTER
Gain & Zero Adjustments
Potentiometer R34 sets the wind direction zero.
Potentiometer R40 sets the wind direction gain.
The adjustments may be sealed with electronic
grade silicon rubber to prevent tampering by unau-
thorized personnel.
1. Refer to Figure 7. Connect a jumper between
terminals 4 & 5 of the terminal strip marked “WIND
VANE”. This simulates a signal corresponding to
zero degrees of azimuth.
2. Adjust the potentiometer marked “DIR. ZERO”
to produce a 4 ma loop current.
3. Connect a jumper between terminals 3 & 5 of
the terminal strip marked “WIND VANE”. This
simulates a signal corresponding to 359 degrees of
azimuth.
4. Adjust the potentiometer marked “DIR. GAIN”
to produce 20 ma of loop current.
CALIBRATION
The instrument is fully calibrated at the factory before
shipment. The following procedure is provided should
adjustment be necessary in the future.
WIND SPEED TRANSMITTER
The wind speed section consists of a frequency to
current converter. A function generator frequency
counter and milliampmeter are required for calibra-
tion.
Note: Calibration potentiometer may be sealed with
silicon rubber to prevent tampering by unauthorized
personnel.
1. Refer to Figure 7. With loop power supplied and
no speed signal, adjust the potentiometer marked
“SPEED ZERO” to produce a loop current of 4 mA.
2. Inspect Table 2 and apply a suitable sinusoidal
signal with a RMS amplitude between 3.5 and 5 V to
simulate the output of the A75-104 Anemometer.
Consult the factory for calibration of other anemom-
eters.
3. Adjust the potentiometer marked “SPEED GAIN”
to produce a loop current of 20 mA.
Table 2
A75-104 Anemometer Output Frequency
100 MPH 58.54 Hz
160 KPH 58.06 Hz
100 KPH 36.29 Hz
50 M/Sec 65.48 Hz
MAINTENANCE
Transmitter
It is recommended that the Transmitter be checked
for calibration each year. Refer to Calibration
section for details.