Vaisala PTU200 - Manual (Page 35)

C HAPTER 6_______________________________________________ CALIBRATION AND ADJUSTMENT
V AISALA _________________________________________________________________________ 31
CHAPTER 6
CALIBRATION AND
ADJUSTMENT
Pressure
The user can select a simple offset or a two-point offset and gain
adjustment and use the LCI command for adjustment of pressure
transducer. The MPCI command is used for the more sophisticated
multipoint correction capability at up to eight pressure levels.
Check first what linear corrections the transmitter is currently using
before attempt to readjust the transducer. As the previous linear
corrections will disappear when new linear corrections are input, the
user has to take into account the previous linear corrections when
deciding about the new ones.
NOTE Entering new linear or multipoint corrections will always cancel the
previous corrections. It is advisable to write down the previous linear
and multipoint corrections so that they will not be lost by mistake.
Entering new linear or multipoint corrections or changing their status
will also automatically cancel the date of calibration of the
transmitter (see CALD command).
T ABLE 6-1 Adjustment and calibration commands
Function Command
listing corrections CORR
linear corrections on/off LC ON/OFF
multipoint corrections on/off MPC ON/OFF
entering multipoint corrections MPCI
calibration date CALD
The linear and multipoint corrections are protected by switch SW4
(see figure 6.2). The switch SW4 is normally in write DISABLE
position (OFF) and the user must change it to write ENABLE position