HD52.3D
- 10 -
V1.11
5.2.1
RS232
SERIAL CONNECTION
For RS232 connection, TX-, RX+ and serial GND signals (pin 9, 3 and 8 of M23 connector) are
used, to be connected respectively to RX, TX and GND signals of RS232 port on PC (pin 2, 3
and 5 of 9-pole SubD connector). The length of RS232 cables should not exceed 15
m.
With RS232 connection, NMEA, MODBUS-RTU and proprietary RS232 protocols can be used.
If the PC is not equipped with RS232 serial ports, the
RS52
adapting cable (with built-in
USB/RS232 converter) can be inserted between the PC and the instrument (see paragraph 5.2.7).
5.2.2
RS485
SERIAL CONNECTION
Thanks to RS485 connection, multiple instruments can be connected to a multi-point network.
Instruments are connected in sequence through a twisted-pair shielded cable for signals and a
third wire for ground.
Line terminations should be placed at the two ends of the network. The cable shield should be
connected to both ends of the line.
The maximum number of devices that can be connected to the RS485 line (Bus) depends on the
load characteristics of the devices to be connected. The RS485 standard requires that the total
load does not exceed 32 unit loads. The load of an HD52.3D… anemometer is equal to ¼ of unit
load. If the total load is greater than 32 unit loads, divide the network into segments and add a
Reference of female
connector solder side
Power supply
Power supply
RS232 Port
RS485/USB or RS485/RS232
converter or data logger
with RS485 port
Other sensors with
RS485 output
Termination
Termination
Reference of female
connector solder side
Summary of Contents for HD52.3D... series
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