Operating Information
7
General Operating Information
Check before using the charger:
are all con-
nections firm, or is there an intermittent contact
at any point in the circuit?
Please bear in mind that it can be dangerous to
fast-charge batteries. For example, if there is a
brief interruption due to an intermittent contact,
the result is inevitably a malfunction such as a
restart of the charge process or an incorrect cell
count detection, which would result in the pack
being massively overcharged.
Charging batteries
During the charge process a particular quantity
of energy is fed into the battery; the Li-Po
Charger 4 automatically calculates the correct
quantity to suit the battery connected to it, and
adjusts the charge rate during the entire charge
process to suit the battery’s condition.
The maximum charge current of the Li-Po
Charger 4 is 3 Amps.
• Batteries must be supervised when on char
ge.
• Batteries must ALWAYS be placed on a fire-
proof surface for charging.
• Faulty or swollen Lithium cells must never be
recharged.
• The battery to be charged must be connec
ted using the original connector supplied with
GRAUPNER Lithium-Polymer cells.
• Ensure that there are no intermittent contacts
at any point in the charge circuit. If there
is a brief interruption due to an intermittent
contact, the result could be a restart of the
charge process, which would result in the
pack being massively overcharged.
Lithium-Polymer cells
The Li-Po Charger 4 is designed solely for char-
ging Lithium-Polymer batteries with a nominal
cell voltage of 3.7 V per cell.
The outstanding feature of Lithium batteries
compared to other battery types is their much
higher capacity.
However, this important advantage is balanced
by increased risks, and it is necessary to adopt
different charging and discharging methods in
order to reduce the risk to a minimum.
It is essential to observe the basic instructions
provided here at all times. Please be sure
also to read the information and safety notes
provided by the battery manufacturer, and keep
within the stated technical limits.
The basic rule is that Lithium-based batteries
can ONLY be charged using special battery
chargers designed and adjusted to suit the
specific battery type (final charge voltage and
capacity).
In contrast to NiCd and NiMH batteries, Lithium
batteries have to be charged using what is
known as a constant current / constant voltage
method. The charge current required is deter-
mined by the battery capacity, and the charger
detects and sets this automatically. Lithium
batteries are usually charged at a charge
current of 1 - 2 C, where a charge current of 1 C
corresponds to the cell capacity. For example, if
a battery has a capacity of 1500 mAh, a charge
current of 1 C is 1500 mA, or 1.5 A. The Li-Po
Charger 4 automatically calculates the optimum
charge current to suit the battery connected
to it, up to a maximum of 3 amps. This makes
it unnecessary to set the charge rate, and the
charger therefore features no such means
of adjustment. Once the specific final charge
voltage for the particular battery type is reached,
the charger automatically reduces the current in
order to prevent the final charge voltage excee-
ding the permissible maximum value.
Liability Exclusion
As manufacturers, we at GRAUPNER are not in
a position to ensure that you observe the correct
methods of operation when installing, using and
maintaining this charger. For this reason we are
obliged to deny all liability for loss, damage or
costs which are incurred due to the incompetent
or incorrect use and operation of our products,
or which are connected with such operation in
any way.
