5 Maintenance & Troubleshooting | Model 356WA |
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5.4 Calibration
The sensitivity of the unit should be checked at two to four week
intervals. Calibration procedures are described in Section 4.7: Calibration.
5.5 Cell
The electrochemical reaction in the analytical process results in the accumulation of lead ions in the electrolyte, making the replacement of the lead electrode or the electrolyte necessary.
5.5.1 Electrolyte Replacement
Replace the electrolyte at least every two months, or even more fre- quently if foreign matter is accumulating in the cell. Remove the cell from is compartment, and drain, clean, rinse, and refill as described in Section 4.2.3: Cell Installation. After the cell is serviced or replaced, calibrate the analyzer as outlined in Section 4.7: Calibration.
5.5.2 Lead Electrode
If electrode is discolored when new, or has obviously deteriorated from use, it may be necessary to clean or replace the electrode. Use the following procedure while referring to Figure
If the lead electrode is simply discolored, clean the entire cell according to the following procedure:
a)Heat a quart of Teledyne cleaning solution to slightly below the boiling point, and completely fill the cell cavity with the heated solution.
b)Let the solution stand for approximately five minutes. Drain and dispose of solution in an approved manner.
c)Repeat steps a) and b).
d)Rinse the cell with distilled water and then fill with electrolyte. Let stand for approximately two minutes and then drain and dispose of electrolyte in an approved manner.
e)Refill the cell with electrolyte, immersing the lower edge of the silver screens to about a 3/32 " depth.
If the lead electrode is obviously beyond repair, it must be replaced.
a)Remove the terminal nuts by removing them from the mounting screws.
b)Carefully remove the screw which holds the screen assembly in place. Remove the screen assembly. Use clean tweezers and do
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