Charge Rates - elv 8500-2 Expert Operating Instructions Manual

12.3.1 Charge rates

C/20: the battery is charged (or discharged) at a very low current corresponding to one twentieth of
its nominal capacity.
C/10: at this setting the battery is charged (or discharged) at a current corresponding to one tenth of
its nominal capacity. A charge factor of 1.4 is used, which means that a fully discharged NC or NiMH
battery is charged for fourteen hours at this current. This charge current is often quoted as the ideal
rate by many battery manufacturers, as even a fairly long overcharge at this current usually does no
harm, although it hardly contributes to a long useful life of the energy storage device. Simple battery
chargers, whose current is just defined by a resistor, also generally deliver a charge current of C/10.
C/5: at this setting a connected battery will be charged or discharged at a current corresponding to
one fifth of the numeric value of its nominal capacity. This level of charge current is sometimes known
as an accelerated charge, and shortens the charge time of a completely discharged pack to around
seven hours.
C/3: the battery is charged or discharged at a current corresponding to one third of the numeric value
of its nominal capacity.
C/2: the battery is charged or discharged at a current corresponding to half of the numeric value of
its nominal capacity.
1 C: this is the lowest setting which is generally termed a fast charge; at this rate the battery connec-
ted is charged or discharged to about 70 to 90% of its nominal capacity within just one hour. The
battery is charged at a current which corresponds to the numeric value of its nominal capacity.
2 C: this charge rate is only available if the external temperature sensor is connected. The charge rate
corresponds to twice the value of the nominal battery capacity.
4 C: this charge rate is also only available if the external temperature sensor is connected. The char-
ge rate corresponds to twice the value of the nominal battery capacity.
direct: selecting "direct" enables you to enter the charge and discharge currents directly, i.e. for
charging and discharging. The value is entered in the same manner as when entering the battery's
capacity.
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Fig. 17: Entering the
charge / discharge interval
Fig. 18:
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