IEEE 450-1987 pdf free.IEEE Recommended Practice for Maintenance, Testing, and Replacement ofLarge Lead Storage Batteries for Generating Stations and Substations.
IEEE 450 items indicate conditionsthat,if allowed to persist for extended periods,can reduce battery life. They do not necessarilyindicate a loss of capacity. Therefore the correc-tive action can be accomplished prior to the nextquarterly inspection, provided that the batterycondition is monitored at regular intervals (not to exceed one week). Note that an equalizingcharge normally requires that equalizing volt age be applied continuously for 35 to 70 h orlonger. (Refer to manufacturer’s instructions.)
(1) An equalizing charge should be given ifthe specific gravity，corrected for temperature and electrolyte level，of an individual cell ismore than 10 points (0.010) below the averageof all cells at the time of inspection.
(2) An equalizing charge should be given ifthe average specific gravity,corrected for temperature and electrolyte levels, of all cells dropsmore than 10 points (0.010)from the averageinstallation value.[Refer to IEEE Std 484-1987[8]，6.3.1(6).]
An equalizing charge should be givenimmediately if any cell voltage is below 2.13 v(see Appendixes) at the time of inspection.
Other Equalizing Charge. If not re-quired by 4.4.2(1) or (2) or 4.4.3,an equalizingcharge should be given at least once every 18months. This equalizing charge can be waivedfor certain batteries based on an analysis of therecords of operation and maintenance inspec-tions (Section 8).
Other Abnormalities.Correct anyother abnormal conditions noted.
State of Charge.State of charge is normallyindicated by specific gravity readings. However,specific gravity readings may not be accuratewhen the battery is on charge following a discharge or following the addition of water. Whencell design permits,specific gravity reading accuracy can be improved by averaging severalreadings taken at different levels within a cell.A more accurate indicator of return to fullcharge is a stabilized charging or float current(see Appendixes).
The following schedule of capacity tests is usedto (1) determine whether the battery meets itsspecification or the manufacturer’s rating，orboth; (2) periodically determine whether the performance of the battery,as found, is within acceptable limits; and (3) if required，determinewhether the battery as found meets the designrequirements of the system to which it is connected.
Acceptance.An acceptance test of the bat-tery capacity (see 6.4) should be made either atthe factory or upon initial installation as determined by the user. The test should meet a specific discharge rate and duration relating to themanufacturer’s rating or to the purchase spec-ification’s requirements.IEEE 450 pdf download.