Young Compass / Serial Interface 32400 - Manual (Page 2)

Page 1
32400-90
MODEL 32400
SERIAL INTERFACE
SPECIFICATIONS*
Wind Speed Input:
Sensor Type: AC Frequency Generator
Sensitivity: 50mV p-p at 10Hz
Range: 0-2000 Hz
Wind Direction Input:
Sensor Type: Potentiometer
Range: 0-5000mV = 0 to 355 degrees
Excitation: 5000mV (limited to 5 mA)
Voltage Inputs (Auxiliary Sensor Inputs):
Resolution: 12-bit
VIN1 and VIN2 0-1000mV
VIN3 and VIN4 0-5000mV
Voltage Outputs:
OUT1 0-5000mV 0-100 m/s wind speed
OUT2 0-5000mV 0-360° wind direction
Serial Output: Full duplex RS-232,
Half duplex RS-485 (2 mS turnaround)
1200, 4800, 9600, 19.2K, & 38.4K baud
8 data, 1 stop, no parity
Operating Temp: -50°C to 50°C
Power: 11 to 30 VDC, 40 mA
Mounting: 1 inch IPS (1.34 inch actual diameter)
Size: 4.75” (12cm) H
0.87” (7.3cm) W
2.12” (5.3cm) D
* Specifications subject to change
1.0 INTRODUCTION
The Model 32400 SERIAL INTERFACE measures wind speed and direc-
tion signals from YOUNG sensors and signals from four general purpose
voltage inputs. The voltage inputs may be used with YOUNG tempera-
ture, humidity, and barometric pressure sensors. One of the voltage
inputs may also be used with a tipping bucket precipitation gauge.
Measurements are available in several serial data formats in either full
duplex RS-232 or half-duplex RS-485 signals. Both continuous and
polled serial outputs are available. When polled, up to 16 units can be
networked together. For marine applications the 32400 produces stan-
dard NMEA serial output sentences. Calibrated voltage outputs for wind
speed and direction are also provided when the 32400 is connected to a
YOUNG wind sensor.
2.0 INSTALLATION
The 32400 is supplied in a weather-resistant enclosure with a mount-
ing adapter that fits 1 inch IPS pipe (1.34 inch nominal diameter). When
used with the YOUNG Wind Monitor, the mounting adapter engages
the Wind Monitor orientation notch. Refer to the WIRING DIAGRAM for
electrical connection details and jumper settings.
3.0 OPERATION
Operation begins automatically when power is applied. Jumpers config-
ure the 32400 for common output formats.
3.1 SIGNAL INPUTS
The 32400 has two special inputs for wind speed and direction from
YOUNG sensors and four voltage input channels for connection to other
meteorological instruments like temperature, humidity, and barometric
pressure sensors. For best performance, sensors should be installed
within 3m (10ft.) of the 32400.
Measurements from the voltage input channels are converted to nu-
merical values (0-4000) and sent in the serial ASCII output string:
VIN1 and VIN2 full scale input is 1000mV DC, therefore:
Input millivolts = Serial output value / 4
VIN3 and VIN4 full scale input is 5000mV, therefore:
Input millivolts = Serial output value x 1.25
If PRECIP or PRECIP POLLED serial output formats are active, VIN4 is
used to count tipping bucket precipitation sensor tips.
Please refer to SERIAL FORMAT DIAGRAM and WIRING DIAGRAM in
the Appendix for additional details.
3.2 JUMPERS
W1 JUMPERS A, B, and C, determine serial output format. Jumper
configurations and associated output format are listed below: 1 signifies
that jumper is installed, 0 signifies that jumper is omitted. See the SE-
RIAL FORMAT DIAGRAM in the Appendix for more details.
A B C SERIAL OUTPUT FORMAT
0 0 0 ASCII Ouput
0 0 1 Polled ASCII
0 1 0 NMEA1
0 1 1 NMEA2
1 0 0 RMYT
1 0 1 PRECIP
1 1 0 PRECIPT POLLED
1 1 1 SOFTWARE Mode
ASCII and RMYT formats force the serial baud rate to 9600. NMEA
formats force the baud rate to 4800.
ASCII and POLLED ASCII are general purpose outputs that may be
used with the YOUNG 26800 or devices that can communicate serially.
NMEA outputs are generally for marine applications. RMYT is a propri-
etary format for use with the YOUNG Wind Tracker.
PRECIP and PRECIP POLLED configure VIN4 as a special input to
count tipping bucket precipitation gauge switch closures. (Requires a
10K ohm resistor from VIN4 to EXC terminal.)
SOFTWARE mode allows output format and other parameters to be set
using serial commands. Please see section 4.0 SERIAL COMMUNICA-
TION and the SERIAL FORMAT DIAGRAM for more information.
W2 & W3 JUMPERS determine output connection type. Only one
connection type may be used at a time. Please refer to the WIRING
DIAGRAM in the Appendix for jumper location and connection details.
JUMPERS OUTPUT TYPE
VOUT Calibrated output for wind speed and direction
OUT1 0-5000mV = 0-100 m/s Wind Speed
OUT2 0-5000mV = 0-360 degrees Wind Direction
232 RS-232 full duplex serial
485 RS-485 half duplex serial
4.0 SERIAL COMMUNICATION
The 32400 uses either full-duplex RS-232 or half-duplex RS-485 signals
for serial communication. RS-232 is the most simple and operates up
distances of 30m (100ft). The RS-485 option is prefered in electrically
noisy environments, in applications where multiple units must be
networked, or in NMEA marine applications where RS-485 signals are
required.