Parameter Throttle Min. (Idle, Throttle Limiter) - Multiplex Royal SX 9 Instructions Manual

The throttle curve for model helicopters is set up in the
menu ¢Control, Throttle. For each of the flight
phases 1 - 3 you can set up a separate throttle curve
with five points, in order to match motor power to the
collective pitch setting of the various flight phases as
accurately as possible. The aim is to obtain a constant
system rotational speed over the full range of collective
pitch. The throttle curve can only be fine-tuned in
flight, and varies according to many parameters (mo-
tor power, carburettor settings, power characteristics,
collective pitch curve, rotor blades, ...). If you change
any one parameter, you will generally need to adjust
the throttle curve again.
The current position of the collective pitch stick is
shown in the graph as a vertical dotted line; this is in-
tended as an aid at the set-up stage.
Example 1: Throttle curve, flight phase HOVER
Simple throttle curve for the hover. The least motor
power is required for negative collective pitch (= de-
scent - in our example: P1 = 35%). The most motor
power is required for positive collective pitch (= climb -
in our example P5 = 85%).
Example 2: Throttle curve, flight phase ACRO
Symmetrical V-shaped throttle curve for increased
throttle when climbing in normal and inverted flight:
Special case: throttle Curve = OFF for electric heli-
copters with brushless motors in governor mode:
In this case a throttle curve does not need to be set up
at the transmitter. When set to governor mode, the
speed controller provides for a constant system rota-
tional speed; all it requires is a fixed pre-set value for
the requisite system speed in each flight phase. The
throttle curve can be switched off by setting the pa-
rameter Curve = OFF in the menu ¢Control,
Throttle. In this case the values of P1 ... P5 are
automatically the same (= fixed value), regardless of
the point which you address.
Throttle curve AUTOROT(ation):
The fourth flight phase for model helicopters is the
auto-rotation phase (AUTOROT, auto-rotation = emer-
gency landing if engine / motor fails). This phase al-
ways has highest priority amongst the flight phases,
i.e. if you operate the switch assigned to auto-rotation,
the transmitter immediately switches to the AUTOROT
flight phase, regardless of the position of the flight
phase switch for Phases 1 - 3. A curve for Throttle
is not set; instead a fixed value is used, which allows
you to set a fixed throttle position (e.g. safe motor idle
or motor OFF in the case of an electric power sys-
tem). The auto-rotation flight phase is primarily used
for practising auto-rotation landings.
Points P1 ... P5 cannot be set separately, i.e. chang-
ing any one value also changes all the other points.
The fixed throttle value for auto-rotation is reduced or
increased:
Note:
At any one time the screen can only display the throttle
curve for the active flight phase. If you wish to change
the throttle curve, please remember that you must first
activate the appropriate flight phase before you actu-
ally alter the value.
15.4.12. Parameter Throttle Min. (idle, throttle
limiter)
The parameter Min. defines the idle speed of the
power system when the throttle limiter is at minimum
or idle. If your model is powered by a glow engine, this
is the speed which is required for starting the engine
and maintaining a safe idle (approx. 20%). For electric-
powered models the setting should be 0% (= motor
OFF). This parameter applies to all flight phases, and
can be adjusted if necessary using the idle trim (trim
buttons for the collective pitch stick) ().
The horizontal dotted line in the graph shows the posi-
tion of the throttle limiter in all flight phases. The throt-
tle limiter restricts the throttle setting.

Tip:
If you wish to adjust the idle (parameter Min.), first
move the throttle limiter to the idle position. The
change in the Idle setting Min. can then be seen di-
rectly from the horizontal dotted line which indicates
the throttle limiter:
Manual
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