PowerBox Systems PowerBox Cockpit SRS User manual

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Dear customer,
We are delighted that you have decided to purchase the PowerBox
Cockpit / Competition SRS from our range.
We hope you have many hours of pleasure and great success with your
new PowerBox.
1. Product description
The PowerBox Competition SRS and Cockpit SRS incorporate SRS
technology, and since their introduction in 2010 they have gained wide
acceptance as the current state of technology. SRS stands for Serial
Receiver System: in contrast to conventional backer systems, the servo
information is transferred from the receiver in the form of a digital serial
signal. This reduces the physical connection between the receiver and
the PowerBox to a single cable. It is also straightforwardly possible to
connect a second receiver, which takes over the entire control system in
full, without any restrictions, if the first receiver should fail.
All the essential components for a secure power supply voltage - ICs,
micro-controllers and electronic circuits - are duplicated. The
outstanding features of this High-End power supply unit are a raft of the
latest innovations, unrestricted channel assignment (channel-
mapping) at the outputs, integral high-resolution graphic OLED screen,
door sequencer capable of multitasking with Setup Assistant, four
match-channels and the facility to bind to the downlink channels of
various manufacturers.

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Features:
- SRS: Serial Receiver System provides the facility to use receivers
with serial interface: Spektrum DSM2 and DSMX, Multiplex M-Link,
Futaba S-Bus, Graupner HoTT, Jeti R-SAT, JR DMSS.
- Unrestricted channel assignment of the PowerBox outputs
- Integral high-resolution graphic OLED screen with 128 x 64 pixels
- Particularly user-friendly menu-based programming using the
SensorSwitch
- Door sequencer: six freely programmable outputs with set-up
assistant
- Channel lock when undercarriage is retracted
- 12 channels inclusive one channel for the doorsequencer in the
Cockpit Version
- 14 channels in the Competition version
- Signal amplification and interference suppression for 12 channels
and 21 servos in the Cockpit version
- Signal amplification and interference suppression for 14 channels
and 18 servos in the Competition version
- Synchronised servo output for totally synchronous servo response
- Flight recorder: records Lost Frames and fail-safe periods for all
receivers connected to the backer
- Variable frame rate, range 9 ms - 21 ms
- 16-bit processor for fast, high-resolution signal processing
- Four match-channels, each for two servos. Accurate adjustment of
all eight servos
- Double regulated output voltage for receivers and servos
- Can be connected to Spektrum, HoTT and Multiplex MSB downlink
channel bus systems
- Direct transmission of battery voltages and capacities to the
transmitter
- Separate voltage and capacity displays for each battery
- Software-selectable servo voltage: 5.9 V or 7.4 V
- Minimum value memory displays any voltage collapses
- Large-area heat-sinks for high regulator power
- Regulator monitor, regulator malfunction indicator
- Support for three battery types: LiPo, NiMH / NiCd, LiFePo
- Suppresses any servo feedback currents which might develop
- Can be updated using the PowerBox USB Interface

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2. Connections, controls
The following illustrations show the essential sockets and controls:
Left: socket fot Spektrum telemetry
Right: SensorSwitch socket
Socket for USB Interface and
telemetry: MSB und HoTT
SET-Button
Power-on status LEDs
Switch buttons for Battery 1 and 2
Door sequencer outputs
Servo sockets
OLED screen
Battery input,
Battery 1 and 2
Serial inputs

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3. First steps, the unit in use:
In the following instructions we do not differentiate between the
PowerBox Cockpit SRS and Competition SRS, since the method of
programming the two units is absolutely identical. The only difference is
that the PowerBox Cockpit SRS includes the door sequencer
function, whereas the PowerBox Competition SRS does not.
3.1. Connections
Plug the batteries into the MPX connectors on the backer with correct
polarity. We recommend PowerBox Batteries of 1500mAh,
2800mAh, 3200 mAh or 4000mAh capacity. If you prefer to use other
makes of battery, or packs you have assembled yourself, please take
particular care over polarity - it is always better to check twice rather
than make a mistake. If you connect a battery to the backer incorrectly,
this will immediately ruin the associated regulator. The unit does not
feature reverse polarity protection, as this minimises power losses
between battery and backer. The +markings are printed clearly on the
case cover.
Connect the SensorSwitch to the appropriate red socket. Note that the
ribbon cable must run upwards. In models subject to powerful vibration
we recommend that you secure the ribbon cable at a minimum of one
point in order to prevent the connector working loose and falling out.
Although this would have no effect on the switched state of the backer,
it would prevent you switching it off.
Do not connect the receiver yet! Please read Point 3.7. to establish
the essential initial settings.
3.2. The procedure for switching on and off
The method of switching the unit on and off is very simple, and the
process effectively eliminates the possibility of changing the backer’s
status accidentally. This is the procedure
Locate the SET button on the SensorSwitch and hold it pressed in until
the central LED glows red. Now press buttons I and II in turn to switch
the backer on.
Repeat the procedure to switch off: hold the SET button pressed in, wait
until the central LED glows red, then confirm by pressing buttons I and
II in turn.

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Your PowerBox stores the last switched state (on or off). That means:
if the backer is switched off using the SensorSwitch, it stays switched
off.
Once switched on, the backer can only be turned off again using the
switch unit. Intermittent contacts or interruptions in the power supply
cannot cause the backer to be switched off.
3.3. Main screen display
When switched on, the unit’s integral screen shows this display:
Key to the individual display points:
- Digital voltage display:
This extremely accurate display allows you to read off the voltage of
the battery directly, i.e. the voltage which is present at the input of the
PowerBox.
- Graphic voltage display:
A brief glance into the model provides you with information about the
batteries’ state of charge. This display is always correct for the type of
battery you have selected. This means that the bar will extend right to
the top of the box if the connected battery is fully charged - assuming
that you have set the correct battery type. If the bar only fills the
bottom third of the box, then the corresponding battery is almost flat.
This indicator is supplemented by the residual capacity display.
- Residual battery capacity:
This display shows the momentary capacity value of the battery -
again, assuming that you have previously set the battery type
correctly. This display is capable of providing very accurate
information about the remaining battery capacity, although ageing
effects or defective batteries may falsify the value. In practice this
means that you should always take both values into account: if the
remaining capacity appears to be high, but the voltage has already
fallen to a low level, you should consider it an urgent necessity to
check the battery more closely.

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- Graphic indicator of battery charge state:
This display is set to match the capacity you previously entered for the
batteries connected to the backer. Assuming that the battery is of good
quality, this means: if the bar only reaches the half-way point, then the
battery is still half-full.
- Operating time:
This figure shows the elapsed time since the last RESET. It is
important always to carry out a RESET after each battery charge
process.
- Output voltage:
This value displays the backer’s exact output voltage. The voltage fed
to the servos and receiver is the exact value displayed here.
Note:
The residual capacity of the two batteries as displayed on the screen is
likely to drift apart as the packs are discharged; this is due to minor
differences in the rate of discharge of the batteries through the
PowerBox. This by no means indicates a fault in the PowerBox; in fact
it proves that the system features genuine redundancy. Here at
PowerBox Systems we take great trouble to compensate for manu-
facturing tolerances between the two regulators, but it is never possible
to produce a system which is completely devoid of tolerances. The only
method of discharging two batteries at 100% identical rates is to use a
system fitted with only one regulator. However, such systems cannot be
claimed to offer redundancy!
3.4. After the charge process
The PowerBox must be reset after each charge process, otherwise it is
impossible for the unit to display reliable values for energy consumption
and operating times. This is the reset procedure:
With the system switched on, locate both buttons I and II on the
SensorSwitch and press them simultaneously; hold them pressed in
until the following screen display appears:

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3.5. Basic settings
The PowerBox Cockpit / Competition SRS feature a new kind of
graphic OLED screen, intended to do away with old-fashioned
programming methods based on flashing LED codes, morse code
beeps or obsolete mechanical jumpers. The screen provides the basis
for an extremely user-friendly control system, and eliminates the need
for a supplementary setup unit or programming device. The
SensorSwitch is employed as a convenient means of entering settings
within the menu system, and since the SensorSwitch is always used as
the main ON / OFF switch, it is always installed in the model, so you
cannot forget it. Wherever possible the screen provides full information
in English; few abbreviations are used. The overall result is an intuitive
method of programming which is a great advantage at the flying field, as
you will rarely need to consult the operating instructions.
This is the basic rule in programming: buttons I and II are used to
move the cursor or change values, while the SET button is used to
select or confirm your inputs.
The breadth of functions offered by the PowerBox Cockpit /
Competition SRS is enormous, but the unit is by no means difficult to
operate. To provide a clear idea of the sequence required in order to use
the backer, we have drawn up a brief list of operations
1. Battery setting Point 3.6
2. Setting the receiving system Point 3.7
4. Output mapping and Failsafe Point 3.8
5. Servo matching and door sequencer Points 4 and 5
6. Fail-Safe settings Point 3.9
3.6. Battery settings
These settings should always be entered first, so that you have an
accurate view of the state of the battery while you carry out further
adjustments. In the screenshot below you will see the default settings of
the PowerBox Cockpit / Competition SRS. If you wish to change
them, this is the procedure:

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- Switch both batteries on.
- Press the SET button and hold it pressed in until the following display
appears:
- Press button II until the cursor (hollow circular ring) lines up with
Power Manager, then press the SET button. The following display
now appears:
If you wish to change one of the settings, use buttons Iand II to move
the cursor to the appropriate menu point, then press the SET button to
select it (cursor changes to a solid disc). You can now alter the value
using buttons Iand II. Once you have selected the desired value, press
the SET button to confirm it; this saves (stores) the new value. Select
the menu point OK to return to the main menu.
NOTE: the presence of a solid disc (instead of a ring) indicates that you
are in a menu point.
It is possible to alter a value more quickly by holding one of the two
buttons Ior II pressed in; the value then starts to change slowly in the
corresponding direction, and the rate of change accelerates with time.

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Key to the individual menu points:
- Chemistry:
this is where you set the battery type. Three different types of battery
are available:
• Two-cell LiPo
• Five-cell NiMH
• Two-cell LiFe
- Capacity:
you can enter the nominal capacity of your batteries at this point.
- Output voltage:
you can select the output voltage to 7.4V or 5.9V
CAUTION: if you intend to select the 7.4V output voltage, please ensure
before you make the change that all the consumer units connected to
the unit, i.e. all servos, receivers and gyros, are compatible with a 7.4V
supply. Information on this subject can be found in the instructions for
these components supplied by the manufacturers.
Compared with a direct, unregulated voltage of 8.4V, the advantage of
a stabilised 7.4V supply is that the voltage is always constant. This
means that the servos in your model always run at the same speed and
with the same torque, regardless of the manoeuvres you fly. For
example, if you were to operate the servos on the unregulated voltage
of LiPo batteries, their running characteristics would alter as the freshly
charged batteries steadily discharged during the flight. Another major
advantage of a regulated 7.4V voltage is that it completely eliminates
damaging voltage peaks (spikes); this extends the useful life of the
servos substantially.

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3.7. Setting the receiver system
Caution:
Please ensure that you have set the correct receiver type before
connecting the receivers. This is important, because the Spektrum
system operates on only 3.3V, whereas all other receivers work on 5.9V
or 7.4V. For example, if you set the receiver system to Futaba and
connect a Spektrum Remote Receiver, the Spektrum Remote
Receivers will be ruined!
If this setting is not selected, the subsequent functions, settings and
assistants only work in a restricted manner.
Switch the PowerBox on as described above. Hold the Set button
pressed in for a few seconds, and the menu system appears. Select the
RX/TX SETTINGS point; the first point in the TX-SYSTEM menu
enables you to select your radio control system:
• Spektrum DSM2 and DSMX:
If you select Spektrum DSM2 or DSMX, the additional menu point BIND
now appears. Whether you select the DSM2 or DSMX option depends
on your transmitter type - not on the satellites connected to the system.
For example, if your transmitter operates on DSM2, but the satellites
are DSMX types, select DSM2 at this point (for example, this applies to
all Spektrum modules fitted to MC-24 transmitters).
Now connect your satellites, and select the BIND menu point; at least
three satellites must be connected. Even if two of three satellites were
to fail in flight, SRS technology allows the PowerBox to continue to
function correctly with just a single satellite.
All satellites connected to the system now flash, and can be bound to
the transmitter.

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The following systems are connected to inputs RX1 and RX4 using the
three-core patch-leads supplied in the set:
• Futaba S-BUS:
Set the receiver or receivers to “Normal Mode” - not “High-Speed
Mode”.
If you are using the R7008SB receiver it is particularly important to set
Output 8 to S-Bus, and to use this output. Do not use the S-Bus2 output!
Naturally the receiver’s S-Bus2 socket can be used for Futaba telemetry
accessories.
• Multiplex M-Link:
The MPX receiver or receivers must be set to “Digital Output”. This can
be selected using the Pro - Mate device or a USB adapter (Multiplex or
PowerBox USB interface) and a PC. The software required for this is
called “Multiplex Launcher”, and is available as a free download from the
Multiplex website. You should also set the fail-safe time to 0s; this is
important if you wish to use two receivers, as it ensures a fast
switch-over if signal loss occurs. Turn off the telemetry on one receiver.
• SJ HoTT:
If you wish to use a HoTT receiving system, the SUMD signal must be
activated at the receiver. Use the SmartBox or the transmitter’s
Telemetry menu to set “CH OUT TYPE: SUMD OF 16”.
“OF” means that the receiver switches the SUMD signal off if signal loss
occurs. The SRS system detects this within a few milliseconds, and
switches over to the second receiver. If you intend to use only one
receiver, you can also set FS or HD.
• Jeti Duplex PPM:
Connect two R-Sat2 satellites directly to RX1 and RX4. One satellite is
operated as “Clone”, the other as “Normal”. The following settings have
proved effective in practice:
- Output Mode: Computed
- Signal Fault: off
- Signal Fault Delay: 0.5s
- Output period: 24ms (if you are using 12 to 16 channels, set this to 28ms)
- PPM 8, 9, 12, 16 according to your transmitter / transmitter module

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• Jeti Duplex EX:
The digital signal employed by Jeti is substantially faster and more
accurate than a PPM signal. The R-SAT2 satellites must be loaded with
software version 3.11 or later in order to be able to switch the EX signal
on. Set the following points in the sequence stated below:
- Output mode: PPM Positive
- No. of channels: 16 channels
- Output mode: EX Bus
- Output period: Auto
- Failsafe: Disabled
Note: in the case of the R-SAT2 the EX signal must be connected to the
EXT output - not to PPM-out. A more detailed description of the
procedure can be found in the Support Forum on our website, including
information on the subject of telemetry.
• JR DMSS:
In the case of the JR DMSS system you must use a receiver with X-Bus
output. This is the procedure:
- Connect the Bind plug to receiver 1
- Move to the “SYSTEM LIST” menu at the transmitter, and select “BIND
& RANGE”
- Select the “BIND” point, and wait until the LEDs light up green
- Move to the “X-BUS” point in the menu, and select “MODE.A”
If you are using two receivers, disconnect the first one at this point and
repeat the procedure with the second receiver. A more detailed
description of the procedure can be found in the Support Forum on our
website.

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3.8. Output Mapping
The OUTPUT MAPPING function allows the channels to be assigned in
any sequence you like. This makes it possible to connect the servos to
the sockets which best match the wiring arrangement in your model.
The only outputs which have a fixed assignment are those for the door
sequencer. By default the outputs have a standard assignment.
Caution: Disconnect the mechanical linkages from the unmatched
servos before connecting them to the backer, noting the setup
information under Point 4.
The letters to the left of the colon (:) are the channel outputs, as printed
on the case of the PowerBox Cockpit / Competition SRS. The
numbers to the right of the colon are the channels as they arrive from the
transmitter. The FS or HD to the right of the numbers indicates Fail-Safe
or Hold mode. Each channel can be set up individually for the unlikely
eventuality of signal loss (when two receivers are in use).
It is now very simple to position the cursor in front of a letter, press the
SET button, and assign an input channel to the selected output using
the I and II buttons.
If you press the SET button again, you can toggle between FS and HD
using the I and II buttons. Pressing the SET button once more stores the
assignment automatically.
It is also a very simple matter to arrange for the same input channel to
be present at multiple outputs, if you want more than one output to
generate the same function.

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Explanation of FS and HD:
• FS: If there is a complete loss of signal at all receivers connected to
the system, this output runs to a previously determined position. See
Point 3.9. for information on defining this position.
• HD: If there is a complete loss of signal at all receivers connected to
the system, this output remains in the last known valid position.
3.9. Teaching the failsafe positions
Access the OUTPUT MAPPING menu and set the appropriate outputs
to fail-safe as shown above. Now leave the OUTPUT MAPPING menu
and select the RX/TX SETTINGS menu, where you will find the TEACH
FAILSAFE POSITIONS menu point.
Use the transmitter to move all the model’s control surfaces, the
undercarriage and the throttle to the positions which you want them to
take up if a fail-safe situation should occur, then press the SET button:
this action stores your selected positions.
Check the settings by moving all the functions to any “non fail-safe
position” at the transmitter - e.g. move throttle to “full-throttle” - then
switch the transmitter off. All the outputs which are marked FS in the
OUTPUT MAPPING menu should now move to the previously set
positions, whereas all outputs not marked FS remain in the last known
position.
Note: thanks to the backer’s integral SRS system, and the facility to
operate two receivers simultaneously, the chances of complete
transmission failure are virtually zero. This claim is based on our three
years of experience with existing SRS products.

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4. Servo Match Function
The Servo-Match function provides the facility for adjusting the centre
position and end-points of the servos connected to the backer. If you
have a model aircraft with more than one servo per control surface, this
makes it possible to set up multiple servos to move to identical positions
at identical times. Since this ensures that the servos do not work against
each other, their effective life is increased, and more power is available
to move the control surfaces; matched servos also draw lower current.
It is also possible to reverse the direction of rotation of individual servos.
This function is useful if you wish to employ fewer channels at the
transmitter. For example, the right and left elevators, or the right and left
landing flaps, can be controlled using only one radio channel. In models
such as jets and warbirds, which by their nature have a large number of
working systems, this feature can be very important, but it can also
make transmitter programming much easier with other types of model.
Select SERVO-MATCHING in the Main menu, and the following screen
display appears:
To ensure accurate servo matching, the output to be adjusted must first
be initialised. Leave the associated transmitter stick at centre. Move the
cursor to INIT OUTPUT and press the SET button. Now move the
transmitter stick to both end-points.
The graphic display shows the movement of the upper arrow, which
indicates the input signal. The bar inside the box shows the movement
of the output. The three lower arrows indicate the centre and end-point
positions which are ‘learned’ in this process.
Note: if the channel has not yet been initialised, it is not possible to
select the START SERVOMATCHING and REVERSE SERVO points.

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The following examples illustrate the correct procedure for the
Servo-Match function:
a) Fine-tuning multiple servos to operate on a single control
surface; in this case the aileron of the right-hand wing.
- Disconnect the linkages to the - as yet unmatched - servos, to avoid
them being subjected to severe forces during the adjustment
procedure.
- Assign the output to the appropriate socket in the OUTPUT
MAPPING menu.
- Set up one servo (generally the inboard one - SERVO 1) in
mechanical terms, using the transmitter if necessary; continue
adjusting until the centre point and the maximum end-points are
exactly as required.
- Now access the Servo-Matching menu and select the servo to be
matched. In our example this would be OUTPUT B and SERVO 2.
- Initialise OUTPUT B as described above.
- Move the cursor to START SERVOMATCHING →but do not press
the SET button at this stage!
- At the transmitter, move the aileron stick to the position to be
adjusted, then press the SET button.
- You can now release the aileron stick: the PowerBox maintains this
position. You now have both hands free, and can adjust the position
accurately with one hand, using buttons I and II, whilst checking the
length (matching) of the disconnected ball-link at the horn with the
other hand.
- Press the SET button again to conclude this adjustment.
- Complete the set-up procedure for the centre position and both
end-points before re-connecting the servo linkage.
- If you need to carry out further adjustments to another end-point or
centre position, move the aileron stick in the desired direction again,
and press the SET button again to start the procedure.
- Repeat the procedure with all the servos connected to the same
control surface.
Note: if your model is fitted with very large ailerons, it can be
advantageous not to match the servos with 100% accuracy. If the
servos are precisely matched, gearbox play may allow aileron flutter to
develop. You can eliminate this risk as follows: first match the servos
exactly to each other, and then press buttons I or II two or three times to
reduce the effect of lost motion in the servo gears to a controlled extent.

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b) Reversing an output when servos are installed in a
“mirror-image” arrangement: in this case left and right landing
flaps.
- Disconnect the linkage to the left-hand landing flap, to avoid the servo
being subjected to severe forces during the adjustment procedure.
- Assign the output to the appropriate socket in the OUTPUT
MAPPING menu. In our example: right landing flap to OUTPUT D,
SERVO 1 and left landing flap to OUTPUT D, SERVO 2.
- First set up the right-hand landing flap servo in mechanical terms,
using the transmitter if necessary; continue adjusting until the centre
point and the maximum end-points are exactly as required.
- Now access the Servo-Matching menu and select the servo to be
matched (left landing flap SERVO 2).
- Move the landing flap switch to the centre position - not one end-point!
- Now select: INIT OUTPUT
- The output is initialised by moving the switch on your transmitter to
both end-points. If you have set up a delay at the transmitter, wait until
the end-point has been reached.
- Use the SET button to select REVERSE SERVO. A tick appears after
the function, and the left-hand landing flap servo now operates in the
correct direction.
- Move the cursor to START SERVOMATCHING and press the SET
button.
- Use button I or II to adjust the centre position of the left-hand landing
flap to the exact position required, then press the SET button.
- Move the transmitter switch to the “flaps extended” position, then
press the SET button again.
- Now set the appropriate end-point using button I or II before
concluding the procedure with the SET button.
- Move the transmitter switch to the “retracted” position, then press the
SET button again.
- Now set the corresponding end-point with button I or II, and conclude
the procedure by pressing the SET button.
- Both landing flaps will now move synchronously.

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5. Setting up the door sequencer
Select the SEQUENCER point at the main menu; this takes you to the
following screen display:
The SETUP ASSISTANT is a new function in the Cockpit SRS which
has been included since software version 15; it makes the task of
programming the actual door sequencer function considerably easier.
The EXPERT MENU provides a very powerful programming interface,
with which you can program highly individual sequences, or
alternatively expand the settings previously entered using the SETUP
ASSISTANT.
The SETUP ASSISTANT describes the TASKs in the actual door
sequencer in accordance with the data you enter. The Assistant guides
you through the settings: everything you need to do is described on the
screen. These printed instructions simply provide additional information
which cannot be displayed on the PowerBox screen due to size
limitations.
The recommended programming procedure is as follows: first enter the
basic settings using the SETUP ASSISTANT. At this point the system
setup will be complete for 90% of all models. If you wish to add more
wheel doors or adjust the sequence to cater for other details, this can be
carried out in the EXPERT MENUE.
Select the SETUP ASSISTANT in the menu; this takes you to the
following screen display:

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Operate the appropriate transmitter switch, and the PowerBox
automatically detects it as the switch which you have assigned to the
retract system. The on-screen arrows should now be located in front of
UP/DOWN. If you find that your retract switch works in the wrong
“sense” (direction), correct it by reversing that output at the transmitter.
Press the SET button again to proceed.
The door sequencer’s method of working is determined in the following
menu:
The following sequences are available:
Mode 1:
Extend undercarriage:
Open wheel doors →extend undercarriage
Retract undercarriage:
Retract undercarriage →close wheel doors
Mode 2:
Extend undercarriage:
Open nosewheel doors →extend nosewheel
Open main wheel doors →extend main undercarriage →close main
wheel doors
Retract undercarriage:
Retract nosewheel →Close nosewheel doors
Open main wheel doors →retract main undercarriage →close main
wheel doors