User Manual

GLOSSARY
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1. Ampere (A) ................... The unit for measuring the flow of electric current.
2. Ampere hour (Ah)......... The current in (A amperes) multiplied by time in (h hours). Used to indicate the capacity of a
battery.
3. Capacity (C)................... Ampere hours that can be discharged from a battery.
4. Cell................................. The minimum unit of which a battery is composed, consisting of positive and negative
plates, separators, electrolyte, etc. In valve regulated lead acid batteries, the nominal voltage
is 2 volts per cell.
5. Charging........................ The process of storing electrical energy in a battery in a chemical form.
6. Cyclic Service ............... The use of a battery with alternative repetition of charging and discharging.
7. Cycle Service Life......... The total number of cycles expected at a given depth of discharge.
8. Deep Discharge ............ (a) Discharge of a battery until 100% of the capacity is exhausted.
....................................... (b) Discharge of a battery until the voltage under load drops below the specified final
discharge voltage. (Over discharge).
9. Depth of Discharge ...... The ratio of discharge capacity vs. the rated capacity of a battery.
10. Discharge ...................... The process of drawing stored energy out of a battery in the form of electrical power.
11. Energy Density ............. The ratio of energy that can be discharged from a battery to the volume of that battery
measured in Watt Hours (WH) per cubic inch, or litre.
12. Float Service.................. Method of use in which the battery and the load are connected in parallel to a float charger
(or rectifier) so the constant voltage is applied to the battery continuously, maintaining the
battery in a fully charged state and to supply power to the load from the battery without
interruption or load variation.
13. Gas Recombination...... The process by which oxygen gas generated from the positive plates during the final stage
of charging is absorbed into the negative plates, reducing the potential at the negative
plates, so repressing the generation of hydrogen.
14. Impedance .................... The ratio of voltage variation vs. current variation in alternating (a.c.) supply.
15. Internal Resistance....... The term given to the resistance inside a battery, consisting of the sum of resistance of the
electrolyte, the positive and negative plates & separators, etc.
16. Life Expectancy ............ Expected service life of a battery expressed in total cycles or time in float service in relation
to a specified application.
17. Nominal Capacity ......... The nominal value of rated capacity. In valve regulated lead acid batteries nominal capacity
is usually measured at the 20 hour rate, although higher rate discharge types have their
nominal capacities given at the 10 hour rate.
18. Nominal Voltage........... The nominal value of rated voltage. In lead batteries, nominal voltage is 2 volts per cell.
19. Open circuit Volts......... The voltage of a battery which is isolated electrically from any external circuit, i.e. the
voltage is measured in a no load condition.
20. Parallel Connection ...... Connection of a group of batteries by interconnecting all terminals of the same polarity,
thereby increasing the capacity of the battery group but not increasing voltage.
21. Recovery Charge.......... The process of charging a discharged battery to restore its capacity in preparation for
subsequent discharge.
22. Sealed............................ The word “Sealed” is used as a relative term when referring to cells in NP batteries
compared with open vented free electrolyte types.
23. Self Discharge .............. Loss of capacity without external current drain.
24. Series Connection......... Connection of a group of batteries by sequentially interconnecting the terminals of opposite
polarity thereby increasing the voltage of a battery group but not increasing capacity.
25. Shallow Discharge ....... Discharge of a battery in which discharge is less than 50% depth of discharge. (D.O.D.)
26. Shelf Life....................... The maximum period of time a battery can be stored, under specified conditions, without
needing supplementary charging.
27. Standby Service ........... General term for an application in which the battery is maintained in a fully charged
condition by trickle or float charging. Synonymous with Float Service.
28. Trickle Charge................ Continuous charging by means of a small current designed to compensate for self discharge
in a battery which is isolated from any load. For valve regulated lead acid batteries,
constant voltage charging is common.
29. Charged Volume............ The power returned to the battery by charging as a percentage of the power taken out during
discharge.
30. VPC (vpc)....................... Term for volts per cell.
E. & O.E.