General Notes On Using The Charger - GRAUPNER ULTRA DUO PLUS 80 Operating Manual

5. General notes on using the charger

Charging batteries
When a battery is charged, a particular quantity of electrical energy is fed into it. The charge quantity is calculated by multiplying charge current
by charge time. The maximum permissible charge current varies according to the battery type, and can be found in the information provided by
the battery manufacturer. It is only permissible to charge batteries at rates higher than the standard (slow) current if they are expressly stated
to be rapid-charge capable. The STANDARD CHARGE CURRENT is 1/10 (one tenth) of the cells' nominal capacity (e.g. for a 1.7 Ah pack the
standard charge current is 170 mA.
Connect the battery to be charged to the charger output sockets using a suitable charge lead (red = positive terminal, black = negative terminal).
Use genuine charge leads of adequate conductor cross-section exclusively.
Be sure to read the information provided by the battery manufacturer regarding charging methods, and observe the recommended charge currents
and charge times. Do not attempt to fast-charge batteries unless they are expressly stated to be suitable for the high currents which this charger
delivers.
Please bear in mind that new batteries do not reach their full capacity until they have undergone several charge / discharge cycles. You should
also be aware that the charger may terminate the charge process prematurely when connected to new packs, and batteries which have been
deepdischarged.
A Ni-Cd pack will normally be warm at the end of a rapid-charge process, but if you notice that one cell of the pack is much hotter than the others,
this may well indicate a fault in that cell. Such packs could fail completely without warning, and should not be used again. Dispose of the battery
safely, preferably taking it to a toxic waste disposal centre.
Ensure that all connectors and terminal clamps make good, sound contact. For example, if there is a brief interruption due to an intermittent con-
tact, the result is inevitably a malfunction such as a restart of the charge process, which would result in the pack being massively overcharged.
A common cause of malfunctions is the use of unsuitable charge leads. Since the charger is incapable of detecting the difference between a
pack's internal resistance, cable resistance and connector transfer resistance, the fi rst requirement if the charger is to work perfectly is that the
charge lead should be of adequate conductor cross-section and should be not be more than 30 cm long Goodquality connectors (gold-contact
types) must be fi tted to both ends).
A battery installed in a radio control transmitter can usually be recharged via the integral charge socket which is fi tted to the transmitter itself.
Transmitter charge sockets generally include a diode which prevents reverse current flow. This prevents damage to the transmitter electronics
should the charger be connected with reverse polarity, or if a short-circuit occurs between the bare ends of the charge lead connectors.
The stated maximum charge current for the transmitter battery must never be exceeded.
To avoid possible damage to the internal transmitter components due to overheating and heat build-up, we recommend that the battery should be
removed from the transmitter's battery compartment prior to charging.
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Operating Manual ULTRA DUO PLUS 80