Vaisala HMT310 - Manual (Page 78)

User's Guide _______________________________________________________________________
78 ___________________________________________________________________ M210619EN-E
Multipoint Adjustment Using Serial Line
You can use the MPC command (applicable from software version 2.0.1
onward) to perform a multipoint adjustment to the relative humidity
measurement. Due to the linear response of the HUMICAP ® sensor, it is
recommended to use the standard two-point adjustments. Use multipoint
correction only if:
- You need to adjust the relative humidity measurement in 3 ... 8
adjustment points.
- You are interested in a narrow range of measurement and want to
optimize the RH measurement performance for that range.
Multipoint adjustment works by means of a correction table that holds
2 ... 6 adjustment points. The idea is that for every point, you enter the
RH reading that the transmitter shows, and the correct humidity reference
value. You can select any reference points from the range of 0 ... 100 %
RH, but Vaisala recommends that the difference between the lowest and
highest reference point is at least 50 %RH.
NOTE Multipoint adjustment is applied “on top” of the standard user-made two
point adjustment (made using serial line commands or MI70). It is
recommended that before you start using the MPC command, you clear
the existing humidity adjustment. This is done as part of the example
multipoint adjustment procedure provided here.
MPC Command Syntax
MPC [quantity] [function]
where
quantity = Quantity to be adjusted. The only available quantity is
RH.
function = Desired function. The options are:
ON – Enable multipoint correction.
OFF – Disable multipoint correction.
LIST – Show correction table.
INIT – Start entering values in correction table.
CLEAR – Remove all values from correction table and
disable multipoint correction.