Tronic 305545, Operating Instructions Manual

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TLG 500 B1 ■ 22
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GB│IE
Operating status displays
The various displays have the following meanings:
■ The LED blinks red and green in 1 second intervals (not for 9 V): The batteries are
being alternately charged and discharged (Refresh-Function: older or long stored
batteries are being refreshed) .
■ The LED blinks red and green in 1/2 second intervals (not for 9 V): The batter-
ies are being discharged to reduce the memory effect .
■ The LED glows red constantly: The batteries are being charged with the maxi-
mum charge current .
■ The LED glows green constantly: The batteries are fully charged and the bat-
tery charger has switched to trickle charge .
Calculating the average charging time
Depending on the type, age and remaining charge in the batteries, the charging
process can take various lengths of time . The average charge time can be cal-
culated using the following formula . Take note however that the times given are
only guiding values .
Charging Time (min) = Battery capacity (mAh) x 1 .4 x 60
Charging current of the device (mA)
Automatic charging control / Retention charging
This battery charger controls the charging time for batteries of the types Ni-Cd
and Ni-MH separately . This control is based on the –Δ U ("minus Delta U")
calculation . In mathematics, with Delta Δ differences are indicated . In this case,
"Minus Delta U" means a negative voltage difference .
This charge identification makes itself useful in the following effects: Should a
battery be charged with a constant current, its voltage rises continuously . When
a battery is full, its voltage reaches a maximum but falls again slightly with further
current flow . This light fall in voltage is recognised by the charging electronics and
the charge process is terminated . The battery charger automatically switches to
"Retention charging" . This means that the batteries are no longer being loaded
with constant current, instead, with short current pulses . This counteracts the self-
discharge and the batteries are kept in a state of full charge .
Timer control
In addition, this battery charger has a timer control which automatically switches
over to retention charging after 15 hours . This serves as an additional protection
against overcharging should the charge termination not respond due to a possibly
defective battery .