Average charging times
Depending on the type, age and remaining charge
in the batteries, the charging process can take va-
rious lengths of time. The average charging time
can be taken from the following table. Take note ho-
wever that the times given are only guiding values.
Type AAA batteries
Capacity
Ni-MH
900 mAh
245 Min.
300 mAh
---
Type AA batteries
Capacity
Ni-MH
2500 mAh
225 Min.
800 mAh
---
Type C batteries
Capacity
Ni-MH
4000 mAh
360 Min.
1800 mAh
---
Type D batteries
Capacity
Ni-MH
4500 mAh
400 Min.
1800 mAh
---
9V Block batteries
Capacity
Ni-MH
200 mAh
280 Min.
100 mAh
---
Ni-Cd
---
80 Min.
Ni-Cd
---
70 Min.
Ni-Cd
---
160 Min.
Ni-Cd
---
160 Min.
Ni-Cd
---
140 Min.
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Calculating the charging time
Current time (Min.) =
Capacity of the battery (mAh) x 1,5 x 60
Charging current of the appliance (mA)
Automatic charging control/
Retention charging
This Universal Battery Charger controls the charging
time for rechargable 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
described.
„Minus Delta U" in this case means a negative
voltage difference.
This charge identification makes itself useful in the
following effects:
Should a battery be charged with a constant cur-
rent, its voltage rises continuously. When the battery
is full, its voltage reaches a maximum and falls light-
ly with further current flow. This light fall in voltage is
recognised by the charging electronics and the
charge process is terminated. The Universal Battery
Charger automatically switches to „Retention
charging". This means that the batteries are no lon-
ger being charged with continuous power, but with
short power impulses instead. This counteracts the
process of self-discharge, thus retaining the batteries
in a fully charged condition.