MODEL 54eA | SECTION 7.0 |
| CALIBRATION - DISSOLVED OXYGEN |
7.4 CALIBRATING THE SENSOR AGAINST A STANDARD INSTRUMENT
The analyzer and sensor can be calibrated against a standard instrument. For oxygen sensors installed in aera- tion basins in waste treatment plants, calibration against a second instrument is often preferred. For an accurate calibration be sure that…
1.The standard instrument has been zeroed and calibrated against
2.The standard sensor is immersed in the liquid as close to the process sensor as possible.
3.Adequate time is allowed for the standard sensor to stabilize before calibrating the process instrument.
Calibrate main sensor Zero main sensor Adjust temperature
4.From the main display, press any key to obtain the main menu. With the cursor on “Calibrate,” press Enter (F4).
NOTE
If Hold was enabled in Section 5.6, the hold screen will appear. To activate hold, refer to Section 5.6, step 11.
ExitEnter
Calibrate in air Calibrate in process Barometric pressure
ExitEnter
8.32ppm
Stabilizing . . . Wait
Abort Cont
8.32ppm
Calibrate : 8.32 ppm
ExitEdit
Press Enter (F4).
5.The screen at left appears. Press the ê key once to move the cursor to “Calibrate in process.” Then, press Enter (F4).
6.Press Cont (F3). “Wait” flashes until the sensor is stabilized.
If the controller appears locked, the reading is not stable enough. Increase the amount the concentration is permitted to vary or decrease the stabilization time. See Section 5.11. Repeat the cali- bration. To proceed with the calibration as is, press Cont (F3).
7.Once the reading is stable, the screen at left appears. Press Edit (F4). Use the arrow keys to change the concentration in the second line of the display to the desired value. Press Save (F4) to store the value.
8.Press Exit (F1) four times to return to the main display.
NOTE
If Hold was activated during calibration, “Hold Mode Activated” will continue to flash in the main display. Return the sensor to normal and deactivate Hold. Refer to Section 5.6, step 11.
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