Lucent Technologies Victory WP-93936, Руководство по эксплуатации продукта

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Lucent Technologies Victory Class Batteries WP-93936
9 - 4 Troubleshooting Issue 1 May 2000
Plate
Polarization
Measurements
The life of a lead-acid battery is optimum when it is properly floated at
the minimum recommended string float voltage, operated in a
temperature controlled environment, and is rarely cycled. Application
requirements can make the ideal operating parameters impossible or
compromised. To better understand and monitor the health of a flooded
lead-acid battery, it is possible to measure the plate potentials
independent of the float voltage of a given cell.
This technique makes use of an instrument known as a “third
electrode.” The third electrode is inserted into the electrolyte of the cell
under examination and voltage measurements are made that may be
either direct measurements or converted measurements, depending on
the type of third electrode used to record the polarization potentials of
the positive and negative plates. It is interesting to note that although a
given cell float voltage may be above or below the recommended
average value of cells in a battery, the cell may be operating properly.
This is because the polarization potentials of the positive and negative
plates are within an acceptable range. Third electrode measurement
instruments are available in both miniature lead-acid cells and mercury/
mercurous sulfate cells.
Although the technique has been used almost exclusively by battery
manufacturers and research and development laboratories for years or
under highly controlled field test conditions, some “battery testing
organizations” have added this test parameter for in-depth customer site
evaluations.
Third electrode measurements can inform the experienced battery
technician of the following: if the positive plates are properly polarized
excessive plate corrosion will be minimized while still maintaining the
plates at a sufficient potential and state of charge to avoid sulfation.
It is essential that the negative plates remain fully charged while at the
same time not depressing the potential of the positive plates. The
correct negative plate potential is dependent on individual
manufacturers’ design parameters and vary widely due to the addition
of organic material (expanders) in the negative plates and/or
depolarizers added to the electrolyte.