C&D Technologies RS-1476 Standby Battery Vented Cell - Manual (Page 25)

1.4 Battery Performance Tests
Batteries are rated on their ability to deliver a certain number of amperes or watts to the load for a specified amount
of time before the battery voltage drops to a final cut off voltage. It is important to recognize that the performance of a
cell or battery depends on several factors:
1. the discharge rate
2. electrolyte temperature at the start of the discharge
3. state of charge
4. integrity of the connections
5. operating history and age of battery
Consult your C&D specification sheets for ratings of various cell types.
To be valid, a performance test requires that the following conditions exist:
• A fully charged battery, balanced cell potentials, and specific gravity. In some cases, this may require an equalize
charge or, in cases of sulfation, other action. Consult with the C&D Technical Services Department.
• Battery must remain at float voltage for at least 72 hours prior to test. This is especially important following an
equalize charge to clear the gases developed at the surface of the plates.
• All connections; inter-cell, inter-row and inter-aisle must be optimized to their minimum resistance and all
connections securely tightened. Refer to Part 1, Sections 4.7 and 4.8.
The discharge rate depends upon the type of test. For an acceptance or performance test, the discharge rate should be
a constant current or constant power load equal to the rating of the battery for a selected test duration and to a final
predetermined voltage. In order to facilitate meaningful analysis, any test data submitted to C&D for review must be
collected in accordance with IEEE-450 (latest revision) procedures. If the test is run to determine battery capacity, the
documentation must demonstrate that the battery was fully charged prior to test. Initial readings as well as discharge
readings must be included in the data submitted. All voltage and current measurements must be taken at the battery/cell
terminals.
REFERENCE INFORMATION
A complete description of testing vented lead acid batteries is beyond the scope of this manual but is discussed in
detail in IEEE STD-450 or supplements and other professional standards.
It is important to recognize that standby batteries are designed for a finite number of discharges. Excessive
testing or cycling of the battery can materially shorten battery life. For more information, refer to Part 2,
Section 4, Battery Operation, Float Service.
CAUTION
A battery string must be disconnected from the charging bus before working on individual cells or batteries. In
multi-cell units disconnecting an inter-cell (same container) connector does not guarantee the absence of voltage
or current at the end terminals. A potential shock hazard may therefore exist. This is very important since there is
always the possibility of a small current leak path across an inter-cell partition.
1.5 Connection integrity
Connection integrity is critical to the safe and efficient operation of any battery. This is the sole responsibility of the
installer/end user. Connections must be inspected at least once a year for the following:
• CLEANLINESS: Remove all corrosion by-products and restore as described in PART 1, Section 4.6.
• TIGHTNESS: Re-torque all connections at least once a year to the re-torque values given in Table 3.
Refer to Part 1, Sections 4.7 and 4.8.
• HARDWARE: Replace worn or damaged hardware.
The importance of connection integrity cannot be overemphasized. Take time to check all connections periodically.
Batteries with voltages of 250 volts or greater and/or batteries used in high rate applications should have their
connections inspected at least twice each year.
CAUTION
An improper or loose connection can cause arcing and possible a fire.
PART 4
REFERENCE INFORMATION, TROUBLE SHOOTING & EXTENDED MAINTENANCE (CONTINUED)
RS1476/0215/CD 23 www.cdtechno.com