Young Ultrasonic Anemometer Voltage and Serial Output Model 81000 - Manual (Page 3)

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3. Apply power to the 81000 sensor. There will be a 4 second
delay for initialization then the unit will begin to output data at
four times per second using the following format: speed (m/s)
azimuth (deg) elevation (deg) speed-of-sound (m/s) sonic-tem-
perature (°C). Verify that all values are present on the display.
Typical output is shown below:
0.00 0.0 0.0 346.70 25.14
0.00 0.0 0.0 346.68 25.11
0.00 0.0 0.0 346.76 25.25
0.00 0.0 0.0 346.80 25.30
0.00 0.0 0.0 346.76 25.25
0.00 0.0 0.0 346.80 25.30
0.00 0.0 0.0 346.80 25.30
0.00 0.0 0.0 346.82 25.35
A threshold level of 0.2 m/s is preset from the factory. Wind be-
low the threshold, such as in still air, is output as 0.00 m/s. Azi-
muth may be any value from 0.0 to 359.9 degrees. When wind
speed is below threshold level, azimuth output is maintained at
the last value read before the wind speed went below thresh-
old. Elevation also remains zero until threshold is exceeded.
Speed of sound ranges from 300 m/s to 360 m/s depending on
temperature. At 20°C the value is about 344 m/s. Sonic tem-
perature may be compared to a standard Celsius thermometer
and should agree within ±2°C. If values appear questionable or
any value is not displayed, remove power and check all wiring
connections. If the problem cannot be corrected, contact your
YOUNG representative.
4. Verify sensor response by gently blowing through the measuring
section. Wind from the north side (marked “N”), should produce
a positive SPEED response and an AZIMUTH display corre-
sponding to North (i.e.: values around 359.9 or 0.0 ). Wind from
the opposite direction should produce values indicating south,
(around 180.0) and so forth. Downward wind produces negative
ELEVATION values, upward wind produces positive values.
After proper operation is con rmed, the sensor may be installed.
Complex data collection or serial communication schemes should
be tested and veri ed before nal installation. It is easier to con rm
wiring connections and communication protocol on a test bench
than a tower. Factory settings may be changed by following the
instructions in the next section.
4.0 COMMAND MENU
Sending the ESC character (ASCII 27) three times in quick suc-
cession takes the unit out of OPERATE mode and causes the
COMMAND MENU to appear.
COMMANDS (VERSION 7.0.05 )
-------------------------
R) REPORT
S) SETUP
X) EXIT TO OPERATE MODE
Access each menu item by sending the character associated with
the menu item of interest. Characters may be upper or lower case.
Send "X" to return to OPERATE mode. The following paragraphs
explain the function of each menu item and associated sub-menu.
The version number may differ from that shown above.
NOTE: Command menu access requires standard RS-232 or full-
duplex RS-485 non-bussed communication.
5.0 REPORT
REPORT summarizes current parameter settings. Some param-
eters are for factory diagnostics only and cannot be accessed or
altered by the user. Typical values appear as follows:
PATH LENGTH(cm) CH DELAY(uS) CMP
----------------------------------
A 15.341 1 19.650 516
4 19.550 484
B 15.245 2 23.875 570
5 23.750 524
C 15.146 3 26.675 511
6 26.500 466
OUTPUT FORMAT: CUSTOM
789AB [ 3D-SPEED AZIMUTH ELEVATION SOS Ts ]
WIND SPEED UNITS: m/s
OUTPUT RATE: 4 Hz
SAMPLES FOR AVERAGE: 0
MODE: AUTO
WAKE CORRECTION: YES
ERROR HANDLING: OMIT INVALID DATA
VOLTAGE OUTPUT FORMAT: SPEED, AZIMUTH, ELEVATION, TEMP
VOLTAGE OUTPUT SCALE: 0 TO 25 m/s = 0-5000 mV
0 TO 540 DEG AZIMUTH = 0-5000mV
-60 TO +60 DEG ELEVATION = 0-5000 mV
220K to 320 K DEG KELVIN = 0-5000mV
CORRELATION TOLERANCE: 125
COMPARE SHIFT: 0
HI SPEED ADC SAMPLES: 10
THRESHOLD: 20 cm/s
ACCESS LEVEL: NORMAL
6.0 SETUP
SETUP allows editing operating parameters to suit the needs of a
particular application. The SETUP menu and detailed explanation
of each menu item follows:
SET PARAMETERS
-------------------------
A) AVERAGING
B) BAUD
E) ERROR HANDLING
N) SCALING MULT
O) OUTPUT RATE
P) POLL CHARACTER (ADDR)
S) SER OUT FORMAT
T) THRESHOLD
U) UNITS
V) V OUT FORMAT
W) WAKE CORRECTION
X) EXIT TO MAIN MENU
6.1 AVERAGING
AVERAGING sets the number of output samples used to calcu-
late block averages of wind measurements. With NUMBER OF
SAMPLES TO AVERAGE set to 0, no averaging takes place.
The block average update rate is a function of OUTPUT RATE and
NUMBER OF SAMPLES TO AVERAGE.
Update Rate (Hz) = (OUTPUT RATE)/(SAMPLES TO AVG)
NUMBER OF SAMPLES TO AVERAGE: 0
ENTER NEW VALUE (0 - 320):
6.2 BAUD RATE
BAUD sets the baud rate for serial communication. Faster baud
rates may be required if the output string is long and the output
rate is fast (see OUTPUT RATE). There is also a setting for HALF
or FULL duplex RS-485. HALF duplex may be used in simple
installations where minimal wiring is required and the unit is set
for continuous output. Use FULL duplex when polling or frequent
parameter changes are anticipated. Note that the DUPLEX setting
applies to RS-485 only since the RS-232 is always full duplex by
default.