Vaisala HMP240 User Manual
Page 33
HMP240 series
M210300en
User's Guide
31
5.3.5.4
Selecting the output units
•
Select Unit in the main menu:
•
Use the arrow keys to select the right alternative and press ENT.
metric
non-metric
RH
%RH
%RH
T
°C
°F
Td
°C
°F
dT
°
C
°
F
a
g/m
3
gr/ft
3
x
g/kg
gr/lb
Tw
°C
°F
5.3.5.5
Selecting the calculation mode
Disconnect the security lock jumper!
•
Select More and then again More in the second menu:
•
Select Frost and then the desired alternative with the arrow keys;
FROST ON (default) for frostpoint and FROST OFF for dewpoint
calculation at dewpoint temperatures below 0
°
C.
5.3.6 Output modes
The output modes only affect output through the serial interface: the transmit-
ter accepts all display and LED commands irrespective of which serial output
mode it is in. The HMP240 transmitter has three serial output modes: RUN,
STOP and POLL.
In the RUN mode the transmitter outputs measurements automatically through
the serial interface to a PC or a peripheral. The only command that can be
given through the serial interface is S (stop), which ends the RUN mode.
In the STOP mode serial commands are given to the transmitter. Measure-
ments are then output only by entering command SEND.
The POLL mode is used when more than one transmitter is connected to the
same serial bus; a single transmitter can be addressed and communicated with.