C&D Technologies RS-990 Liberty Series 1000 - Manual (Page 16)

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CAUTION
Use extreme care when installing connectors; maintain a firm
grasp on each connector as it is being installed, to prevent it
from dropping and potentially causing a short circuit.
Note: Over-torquing can damage the post seal causing electrolyte
leakage.
4.4 Checking connection integrity
• Check once again that all units are connected positive terminals to
negative terminals. Measure the battery voltage with a digital
voltmeter. The voltage should be approximately 2.15 Volts (open
circuit) times the number of cells per unit times the number of units
connected in series. Example: 2.15 Volts x 2 cells/unit (model LS 4-
300) x 6 units = 25.8 Volts, representative of the nominal open
circuit voltage of a 24-Volt system.
• Recheck the torque of connections to make certain that there are no
loose connections that could cause a poor connection thereby
creating an arc or spark or a hot connection that on discharge could
melt the lead components.
• Follow the charger manufacturer’s instructions and make the con-
nections to the battery with the charger de-energized.
CAUTION
It is the sole responsibility of the user to check connections.
All connections should be checked at regular intervals to
ensure that connections are clean and tight. Never operate a
battery with loose or corroded connections. When checking
connections, disconnect the battery from the load and the
charging equipment, and follow all precautionary measures
outlined above and the general safety references.
Typical internal cell resistance values are provided in Table 2
according to cell type. In addition a listing of short circuit current in
amperes is provided to further inform the user of the potential energy
available from the batteries.
4.5 Paralleling Batteries
When strings of batteries of equal voltage are connected in parallel,
the total capacity is equal to the sum of the capacities of the individual
strings. C&D Technologies recommends parallel strings when the
required capacity exceeds available Ampere-hour sizes or when
physical arrangement favors this choice. The use of parallel strings
permits maintenance on one string while the other(s) remain function-
al at a somewhat lower reserve time. Limit the number of paralled
battery strings to six.
When paralleling is necessary to obtain required capacity, the cable
size and external cable length should be optimized to match the cable