Vaisala HMP260 - Manual (Page 25)

HMP260 SERIES
HMP260-U017en-1.5 Operating Manual
1997-11-25 19
The RS 232C screw terminal cannot be used if an RS 485/422 serial module
or a digital current loop module is used. See appendices 3 and 4 on how to
install and operate these modules.
In calibrating or changing the settings of the transmitter it can be more con-
venient to use the connector X17, if connector X6 is already in use. This con-
nector, however, transfers only RS 232 signals. If an RS 485/422 serial port
module or a digital current loop module has been installed, it has to be
removed before communicating through the X17 connector.
Fig. 4.6 Location and connections of connector X17
4.3.1 Reverting to factory settings of the serial port
If the serial port settings are not known, no commands can be given via the
serial interface. The settings can be reverted to the factory settings by inserting
a jumper in connector X16. The jumper must be inserted when the power is
on!
X16
cover of the protection unit
Fig. 4.7 Forcing the serial port settings back to factory settings
When the jumper is inserted the serial line factory settings become valid, but
only temporarily. The transmitter must be given new settings; otherwise
the transmitter uses the old, unknown settings after power-up. When the
new settings have been given, the transmitter must be reset. Note that the
RX GND TX
X17