Graupner GmbH & Co. KG MC-20 Manual De Usuario
47
Receiver initialization
Receiver power supply
Among other aspects, the safe operation of a model
depends on a reliable power supply. In the event
that, despite smooth operating rods, fully charged
battery, battery leads with adequate cross-section,
minimum contact resistances at connectors, etc.,
the transmitter indicates repeated receiver voltage
collapses or is receiver voltage is generally too low;
please give attention to the following notices.
Give primary attention to fully charged batteries when
model operation is to be started. Be sure that the
contact surfaces of connectors and switches really
are low resistance. If necessary, measure the voltage
drop across installed switch cables when they are
under load because even new heavy-duty switches
can cause a voltage drop of up to 0.2 V. This value
can increase in contacts by factors as a consequence
of aging and oxidation. The constant vibrations and
jarring also takes its toll on contacts to produce a
creeping increase of contact resistance.
Servos present another possible problem source.
Even rather small servos like a Graupner/JR DS-281
can draw up to 0.75 A of current when it is blocks
under load. Just four of these servos in a "foam"
model can therefore load down the on-board power
supply by as much as 3 A …
Therefore you should choose a power supply which
will not break down under greater loads but rather
always deliver suffi cient voltage. To "calculate"
necessary battery capacity you should always fi gure
on at least 350 mAh for every analog 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.
In any case, it is recommended that several of the six
Among other aspects, the safe operation of a model
depends on a reliable power supply. In the event
that, despite smooth operating rods, fully charged
battery, battery leads with adequate cross-section,
minimum contact resistances at connectors, etc.,
the transmitter indicates repeated receiver voltage
collapses or is receiver voltage is generally too low;
please give attention to the following notices.
Give primary attention to fully charged batteries when
model operation is to be started. Be sure that the
contact surfaces of connectors and switches really
are low resistance. If necessary, measure the voltage
drop across installed switch cables when they are
under load because even new heavy-duty switches
can cause a voltage drop of up to 0.2 V. This value
can increase in contacts by factors as a consequence
of aging and oxidation. The constant vibrations and
jarring also takes its toll on contacts to produce a
creeping increase of contact resistance.
Servos present another possible problem source.
Even rather small servos like a Graupner/JR DS-281
can draw up to 0.75 A of current when it is blocks
under load. Just four of these servos in a "foam"
model can therefore load down the on-board power
supply by as much as 3 A …
Therefore you should choose a power supply which
will not break down under greater loads but rather
always deliver suffi cient voltage. To "calculate"
necessary battery capacity you should always fi gure
on at least 350 mAh for every analog 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.
In any case, it is recommended that several of the six
available connections designated "- +/B" be used for
the supply of power. (These connections are ONLY
intended for battery connections.)
Connect the power supply preferably by way of
the socket/s which are close to connectors of
attached servos. Where only high-power servos are
connected, it may be necessary to use all receiver
battery connections to connect as many as three
PRX receiver power supplies (depending on battery
power). Even where only two batteries are used via 1
PRX it is preferable to use the receiver connections
closest to the servos which draw the most current.
The fi gure below shows an example of a stabilized
receiver power supply (PRX-5A, order no. 4136) for
the connection of two batteries. As an alternative
solution, a switch could be inserted with power supply
cables to two receiver connectors. Such a double
connection not only reduces the risks associated with
a cable break but also ensures a more uniform supply
of power to attached 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
connect different battery types or batteries charged
to signifi cantly 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.
the supply of power. (These connections are ONLY
intended for battery connections.)
Connect the power supply preferably by way of
the socket/s which are close to connectors of
attached servos. Where only high-power servos are
connected, it may be necessary to use all receiver
battery connections to connect as many as three
PRX receiver power supplies (depending on battery
power). Even where only two batteries are used via 1
PRX it is preferable to use the receiver connections
closest to the servos which draw the most current.
The fi gure below shows an example of a stabilized
receiver power supply (PRX-5A, order no. 4136) for
the connection of two batteries. As an alternative
solution, a switch could be inserted with power supply
cables to two receiver connectors. Such a double
connection not only reduces the risks associated with
a cable break but also ensures a more uniform supply
of power to attached 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
connect different battery types or batteries charged
to signifi cantly 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.
PRX receiver power
supply, stabilized
Order No. 4136
supply, stabilized
Order No. 4136
For reasons of safety, do not use battery boxes or dry
cell batteries.
The voltage of the on-board power supply will be
displayed at the bottom right of the transmitter's
screen while the model is in operation.
cell batteries.
The voltage of the on-board power supply will be
displayed at the bottom right of the transmitter's
screen while the model is in operation.
#01
0:00h
Stop watch
Flight tim
K78
0:00.0
4.1V
0:00.0
0
0
0
0
0:00h
M
V
RX VOLT:4.8V
If the adjustable warning threshold (default value
3.60 V) set in the Telemetry menu, see page 260,
is underrun, a visual and an acoustic under-voltage
warning will be issued.
Despite this feature, be sure to check the condition
of the battery at regular intervals. Do not wait for
the warning to be issued before recharging the
battery.
3.60 V) set in the Telemetry menu, see page 260,
is underrun, a visual and an acoustic under-voltage
warning will be issued.
Despite this feature, be sure to check the condition
of the battery at regular intervals. Do not wait for
the warning to be issued before recharging the
battery.
Note:
An overview of available batteries, chargers and
current source test instruments can be found in
the Graupner RC main catalog or in Internet at
www.graupner.de. A selection of suitable Compter
chargers are listed in the table on page 17.
An overview of available batteries, chargers and
current source test instruments can be found in
the Graupner RC main catalog or in Internet at
www.graupner.de. A selection of suitable Compter
chargers are listed in the table on page 17.
Receiver power supply