Endress+Hauser CA76NA, Руководство по эксплуатации

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Maintenance CA76NA
54 Hauser
9. Insert the pH electrode into the first buffer solution.
10. If the value for the measurement potential Meas.pot. mV remains stable for a
minimum of 30 seconds, use the arrow keys to move to the right in the row from pH1
to "---".
11. Press , select "set" and choose to confirm
12. After confirming, the "---" field appears again and the value has been accepted.
13. Repeat steps 8-12 for the second buffer solution.
 Once the calibration has been performed successfully, the device updates the
slope (S) and the zero point shift (E0).
14. Following the calibration, rinse the pH electrode with deionized water.
15. Carefully insert the pH electrode back into the measuring unit.
11.2.5 Calibrating the sodium electrode
During automatic calibration, standard solution is added several times to a defined
sampling volume in the circuit. The sample is circulated through the circuit by switching
the solenoid valves. Switching the solenoid valves and the circuit pump also causes the
system to be rinsed and drained and a laboratory sample to be measured.
The sample must have a low sodium concentration (< 50 ppb), otherwise errors occur.
Automatically calibrating the sodium electrode
The analyzer has a built-in function for automatic calibration. Set the calibration interval
for automatic calibration for this function.
1. Navigate in the menu to Parameters / Measurement Sequence .
2. Define the calibration interval.
3. The analyzer performs a calibration of the sodium electrode as per the defined
interval.
Manually activating automatic calibration of the sodium electrode
Automatic calibration of the sodium electrode must be manually activated only in the
following cases:
• When commissioning the device
• After replacing the sodium electrode
Filling hoses after replacing standard solution
1. Navigate in the menu to Maintenance .
2. To access the Maintenance menu, enter the password 1111 (as-delivered state).
3. Press the key to open the Operating Mode menu item.
4. Select the Manual menu item.
5. Using the key, select the Status: FILL menu item. Press to confirm.
 The analyzer fills the hose from the standard bottle to the valve unit with
standard solution.
Any air in the hose to the standard solution pump is driven out. The dosing loop
is filled with standard solution.
Manually activating automatic calibration
1. Navigate in the menu to Maintenance .
2. Enter the factory password 1111, or a new password that has been assigned.
3. Press the key to open the
Operating Mode menu item.