Vaisala HMP240 - Manual (Page 99)

HMP240
M210300en Appendix 2: RS 485/422 serial port module
97
3.2 Dual loop operation
The following procedure must be repeated with all transmitters.
• Open the transmitter cover.
• Pull out the RS 485/422 serial port module, if it is already mounted.
• Set the serial port of the terminal to 4800 baud, even parity, seven
data bits and one stop bit, full duplex (4800 E 7 1 FDX).
• The serial settings of the transmitter must also be 4800 E 7 1 FDX
and the transmitter must be in STOP mode. If these factory settings
have been changed, they must be returned. Connect the RS 232C port
of the terminal to connector X17 on the top of the main board and
switch the power on.
When dual loop is used, the jumpers in connector X4 on the module board
must be as shown below.
X4
X4
X1 X2
• Set the address of the transmitter; you can choose any number
between 1 and 99. In this example the address is 22:
>addr 22
Address : 22
• Set the serial bus settings according to your system. This setting will
become valid after next RESET or power off:
>seri 2400 e 7 1 f
2400 E 7 1 FDX
• Switch echo on:
>echo on
ECHO : ON
>
• Change the serial output mode into POLL:
>smode poll
Serial mode : POLL
NOTE 1
The SMODE command must be given last.