Lucent Technologies Victory WP-93936, Руководство по эксплуатации продукта

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Lucent Technologies Victory Class Batteries WP-93936
Issue 1 May 2000 Troubleshooting 9 - 3
Cell Reversal
Cell(s) may be reverse charged during a deep discharge. On recharge
these cells may read as high as 4 volts, indicating a high internal
resistance. “Reversed cell” temperatures may rise significantly on
recharge, and immediate action is necessary to avoid permanent
damage to the cell(s). Recharge voltage must be decreased to insure that
the reversed cell(s) do not exceed 3.0 volts or 110 degrees Fahrenheit.
If the cell(s) do not respond to this special charging it may be advisable
to charge the cell individually. A single cell charger is required for this
procedure. Contact your Lucent Technologies agent for additional
assistance.
Measurement
of Internal Cell
Impedance and
Conductance
A technique that has gained popularity, particularly in
“valve-regulated, lead-acid” (VRLA) batteries, is the measurement of
internal cell impedance and/or conductance. Since the plates are not
visible in VRLA batteries many of the visual analytical techniques that
can be used for vented lead-acid batteries are not applicable in sealed
products. Primarily for this reason other methods of analysis have been
developed.
The measurement of internal impedance and/or conductance utilizes
either AC (alternating current) at various frequencies or DC resistance
measured across the cell terminals to determine the degree of
deterioration of the element from a baseline value taken when the
cell(s) was first installed. A change of more than 20% from the value
recorded on original installation may constitute a reason for further
investigation. These techniques are discussed in IEEE Standard
1188-1996, Appendix D. The discussion is intended for VRLA
batteries. There is not a similar reference in IEEE-450 written for
vented batteries.
However, some users of vented batteries have chosen to use the
impedance, conductance, or resistance measurement technique for
additional analytical data. It is important that a baseline be established
upon initial installation of the battery. Subsequent tests may then be
referenced to the original values.