GRAUPNER MC-32 Manual page 56

servo and at least 500 mAh for every digital servo.
For example, from this point of view a battery with
1400 mAh would be the absolute minimum to power
a receiver system with a total of 4 analog servos. But
be sure to also consider the receiver itself into the
calculation because its bidirectional functionality will
draw about 70 mA of current too.
Regardless, it is generally recommended that you
connect the receiver via two cables to the power sup-
ply: cable "1" is to be as usual, plugged into the "12 +
B" port of the receiver and cable "2" at the opposite,
with "11 + B - "label, the end of the edge connector of
the receiver.
For example, by using a switch or voltage regulator
with two leading to the receiver power supply cable.
If necessary, use to connect them to the receiver a V
or Y cable No. 3936.11, see figure, if you need one or
both terminals of the receiver and to connect a servo,
speed controller etc.. They reduce by the double con-
nection to the switch or voltage regulator not only the
risk of a cable break, but also ensure more power to
the connected servos.
If a separate battery is connected to each receiver
battery connection, be absolutely sure the batteries
have the same voltage and power rating. Never con-
nect different battery types or batteries charged to
significantly different levels to the receiver. This can
lead to effects similar to short circuit conditions. In
such cases, insert voltage stabilizers, such as the
PRX-5A receiver power supply, between the batteries
and the receiver.
56 Receiver power supply
For reasons of safety, do not use battery boxes or dry
cell batteries.
The voltage of the on-board power supply will be dis-
played at the bottom right of the transmitter's screen
while the model is in operation:
GRAUBELE Stp
#01 Flt
«nor mal
3.9V
K78
2:22h M
If the voltage falls below the warning thresh-
old – 3.80 V as standard – set in the "RX SERVO
TEST" display of the "SETUP, DISPLAYS" sub-menu
of the »Telemetry« menu, page <?>, then the sys-
tem generates a visual and audible low voltage warn-
ing.
Despite this feature, be sure to check the
condition of the battery at regular inter-
vals. Do not wait for the warning to be
issued before recharging the battery.
Note:
An overview of available batteries, chargers
PRX receiver power
and current source test instruments can be
supply, stabilized
found in the Graupner RC main catalog or in
Order No. 4136
Internet at www.graupner.de. A selection of suitable
Computer chargers are listed in the table on page
<?>.
Receiver system power supply
NiMH 4-cell battery packs
In compliance with the aforementioned conditions,
your Graupner HoTT receiver system can be readily
operated with traditional 4-cell battery packs as long
as the packs have adequate capacity and voltage
0:00
level.
0:00
»
NiMH 5-cell battery packs
HoTT
Five-cell battery packs offer a greater voltage toler-
5.5V
ance than do 4-cell packs.
However, be aware that not every servo available on
the market is able to tolerate the voltage level output
by a 5-cell pack over the long term, this is particularly
true when the battery pack is freshly charged. Some
of these servos react to this with a noticeable "grind-
ing" sound.
Therefore pay attention to the specifications
of the servos you use before making a choice
for a 5-cell battery pack..
LiFe 6.6 V batteries with 2 cells
From a contemporary perspective, these new cells
are the very best choice.
LiFe cells are also available in hard plastic casings
to protect them from mechanical damage. Like LiPo
cells, LiFe cells can be quick charged in suitable
chargers and they are comparatively robust.
This type of secondary cell battery is also rated for
a significantly greater number of charge/discharge
cycles than, for example, LiPo batteries The nominal
6.6 V output of a 2-cell LiFe battery pack does not