Calibrating The Sensor Against A Standard Instrument (In Process Cal); Calibration - Ozone - Emerson Rosemount 1066 Instruction Manual

Instruction Manual
LIQ-MAN-1066
9.7.3 Calibrating the Sensor Against A Standard Instrument
(in process cal)
The adjacent screen will appear prior to In Process Cal
If the In Process Cal is successful, the screen will return to the Cal sub-menu.
The adjacent screen may appear if In Zero Cal is unsuccessful. The screen will return to the
Amperometric Cal Menu.
9.8 Calibration – Ozone
An ozone sensor generates a current directly proportional to the concentration of ozone in the
sample. Calibrating the sensor requires exposing it to a solution containing no ozone (zero
standard) and to a solution containing a known amount of ozone (full-scale standard). The Zero
Calibration is necessary because ozone sensors, even when no ozone is in the sample, generate a
small current called the residual or zero current. The transmitter compensates for the residual
current by subtracting it from the measured current before converting the result to an ozone
value. New sensors require zeroing before being placed in service, and sensors should be zeroed
whenever the electrolyte solution is replaced. The best zero standard is deionized water. The
purpose of the In Process Calibration is to establish the slope of the calibration curve. Because
stable ozone standards do not exist, the sensor must be calibrated against a test run on a grab
sample of the process liquid. Several manufacturers offer portable test kits for this purpose.
To calibrate the ozone sensor, access the Calibration screen by pressing ENTER from the main
screen, select and press ENTER.
The following calibration routines are covered:
1. Zero Cal Zeroing the sensor in solution with zero total chlorine
2. Grab Cal Standardizing to a sample of known ozone concentration
To calibrate ozone:
1. Press the MENU button
2. Select Calibrate. Press ENTER.
3. Select Ozone. Press ENTER.
The adjacent screen will appear. To calibrate Ozone or Temperature, scroll
to the desired item and press ENTER.
Calibration
Section 9: Calibration
April 2017
1.234 µS/cm 25.0 ºC
SN Calibrate?
Ozone
Temperature
83