Vaisala PTB220 - Manual (Page 67)

C HAPTER 7__________________________________________________ ADJUSTMENT AND CALIBRATION
V AISALA _________________________________________________________________________ 61
Offset and gain adjustment
LCI Entering linear corrections
LCI n
where:
n = number of the pressure transducer (1, 2 or 3)
The LCI command is used to enter new linear offset and offset/gain
corrections to the barometer. Note that the user must give the linear
corrections to each pressure transducer separately.
Entering new linear corrections is protected by switch. The switch
SW4 is normally in write DISABLE position (OFF) and the user must
change it to write ENABLE position (ON) to be able to enter new
linear corrections to the barometer.
The previous corrections must first be deactivated using the LC OFF
and/or MPC OFF commands. Pre-calibration of the barometer then
gives the required new corrections. The new linear corrections will
always cancel the previous corrections as well as the valid date of
calibration of the barometer (see CALD command). When the new
linear corrections have been entered, they must be activated with the
LC ON command. Use ESC to abort without executing the command.
In the following, an example of performing an offset adjustment for
pressure transducer P1 and an offset/gain adjustment for pressure
transducer P2 is given.
>lc off
Linear adj.
: OFF
>lci 1
P1
1. reading ? 1013.25
correction ? -0.1
P1
2. reading ?
>lci 2
1.
reading ? 800.00
correction ? 0.05
P2
2. reading ? 1000.00
correction ? -0.02
>lc on
Linear adj.
: ON
Reading Correction Reading Correction
1013.250 -0.100 800.000 0.050
1013.250 -0.100 1000.000 -0.020
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