Description And Function - Ottobock 757L20 Gebrauchsanweisung

5 Description and function

Unlike NiCad batteries, the rechargeable li-ion battery has the benefits of a lower self-discharge,
a higher cell potential and a higher energy density. Li-ion technology offers higher capacities, has
no memory effect and requires considerably reduced charging times.
The Li-Ion Battery Charger 757L20 consists of a Charging Station (fig. 1, pos. 1), a Power Sup-
ply Unit 757L16-* with EU plug (fig. 1, pos. 2), and an additional US plug (fig. 1, pos. 3). For
exchanging the plug, please refer to figure 4.
The battery charger has an operating indicator (green LED, fig. 2, pos. 3) as well as four other
LED indicators:
• Green LEDs (fig. 2, pos. 1 and 1a): Indicate the charging status of the EnergyPacks
• Yellow/red LEDs (fig. 2, pos. 2 and 2a): Indicate malfunctions of the Energy Packs or battery
charger
Before charging, the battery charger conducts a self-test.
In a test procedure, short-circuited or damaged cells are identified and prepared for the CCCV
process (constant current - constant voltage) during the conditioning phase of the charging pro-
cess.
During the CCCV process, the EnergyPacks are charged with a continuously high current until
a certain voltage level is reached. The current then automatically decreases to a lower level until
it is switched off completely.
If the voltage of the EnergyPacks falls below a certain level, the battery charger automatically
switches to trickle charge.
The charging process will also be interrupted when the temperature exceeds 50 °C/122 °F or
falls below 0 °C/32 °F. This is indicated by the yellow LED. The charging process will resume as
soon as the Energy Pack has reached room temperature.
6 Function
6.1 Self-test
Connect the Charging Station to the Power Supply Unit 757L16-* (see fig. 2, pos. 4) and plug
into an electrical outlet. The operating indicator lights up (see fig. 2, pos. 3) showing the battery
charger is ready for use.
Next the battery charger conducts a self-test, during which all other indicator lights will light up
briefly.
6.2 Charging
Insert one or two EnergyPacks into the charging station (fig. 3).
The charging process begins when the indicator lights1 and/or 1a light up.
The charging time for a depleted EnergyPack is approximately 3-1/2 hours. As soon as the Ener-
gyPack is fully charged, the 1/1a indicator light(s) flash and the charging current is cut off.
If the EnergyPack voltage falls below a certain value due to self-discharge, the Li-Ion Battery
Charger automatically switches to trickle charging. The fully charged battery may be left in the
battery charger without becoming damaged.
Notice:
To avoid malfunctions, the electrical contacts of the EnergyPack and of the battery charger
must be kept clean and free of grease. For cleaning please use a dry cotton pad stick. Clean
the electric contacts with a cotton bud and some alcohol on a regular basis.
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