Vaisala DMP248 - Two-Point Temperature Calibration and Adjustement; Using Serial Commands

CHAPTER 6______________________________________________ CALIBRATION AND ADJUSTMENT
VAISALA _________________________________________________________________________ 61
• Connect an ammeter/voltmeter to the analogue outputs (connector
X2). Give command ¡¡l¡. At the first calibration point the
LED on the left flashes; adjust the first point (offset) with the
arrow switches to the same reading with the reference and press
ENT switch.
• After adjusting the offset point and pressing ENT the second LED
from left flashes. Press ENT without changing the output value.
Two-point temperature calibration and adjustement
Using serial commands
• Leave the reference instrument and the transmitter for at least 4
hours in the same space so that their temperatures have time to
equalize. Remove the filter cap prior to calibration.
Disconnect the security lock jumper
before turning the transmitter on!
• Check the transmitter against the reference.
• Give command CT <cr>, enter the first point value and press <cr>:
>CT <cr>
T : xx.x Ref1 ? yy.y <cr>
Press any key when ready
• If you want to see how the sensor stabilizes to the reference
temperature, enter c <cr> instead of the first reference:
T : 0.90 Ref1 ? c <cr>
T : 0.55 Ref1 ? c <cr>
T : 0.55 Ref1 ? 0.0 <cr>
Press any key when ready...
• Change the temperature and again check the transmitter against
the reference.
• Check that the reading corresponds with the reading of the
reference instrument. If not, adjust the second point.
• Press any key, enter the second point value and press <cr>.
T : xx.x Ref2 ? yy.y <cr>