Procedure - Auto Calibration Using Deltav - Emerson ROSEMOUNT 5081-A Instruction Manual

MODEL 5081-A
13.3 PROCEDURE — AUTO CALIBRATION USING Deltav
1. Verify that auto calibration has been enabled. See Section 7.8.
2. obtain two buffer solutions. Ideally, the buffer pH values should bracket the range of pH values to be meas-
ured.
3. Remove the sensor from the process liquid. If the temperature of the process and buffer are appreciably dif-
ferent, place the sensor in a container of tap water at the buffer temperature. do not start the calibration until
the sensor has reached the buffer temperature. thirty minutes is usually adequate.
4. Access: deltaV Explorer/Context Menu
pH Buffer Calibration (method_ph_buffer_cal)
For automatic buffer calibration to occur, the parameter Buffer Standard
(BuFFER_StANdARd) must be set to a buffer standard, and not "Manual".
Method Steps:
a. Prompt: Place sensor in buffer 1.
b. displayed: Current pH Measurement
Current temperature Measurement
Message: Waiting for pH input to stabilize.
c. displayed: Current pH Measurement
Current temperature Measurement
Prompt: Is buffer = x.xx pH?: Yes; Next Buffer; Previous Buffer
use the next or previous buffer buttons to choose the Buffer 1 value being used.
Select "Yes" when that buffer value is reached.
d. Prompt: Place sensor in buffer 2.
e. displayed: Current pH Measurement
Current temperature Measurement
Message: Waiting for pH input to stabilize.
f. displayed: Current pH Measurement
Current temperature Measurement
Prompt: Is buffer = y.yy pH?: Yes; Next Buffer; Previous Buffer
use the next or previous buffer buttons to choose the Buffer 2 value being used.
Select "Yes" when that buffer value is reached.
g. If there are calibration errors, they will be displayed, and the corresponding errors will be shown in
deltaV Explorer/Status/Errors tab.
h. displayed: Current pH Measurement
Current temperature Measurement
New pH Slope Value
New pH Zero offset Value
the method concludes.
88
NOTE
SECTION 13.0
CALIBRATION - pH