Linkage Menu
F X - 4 0
16.10 FAIL-SAFE
FAIL-SAFE SETTINGS
This function is only available in PCM-G3 or PCM-1024 mode.
This means that the corresponding modulation process must
be set at the transmitter, and a matching PCM receiver must
be installed in the model.
In the Fail-Safe menu you can set the following parameters for
channels 1 … 12:
1. ‘HOLD’ mode:
the last fault-free signals are stored tempora-
rily in the receiver, and are passed on to the servos if interfe-
rence should occur. These servo positions are maintained
(‘held’) until such time as valid signals are picked up from the
transmitter again. This is the default mode.
2. (F/S) Fail-Safe position:
when interference strikes, the ser-
vos run to pre-programmed positions which are set at the
transmitter; these settings are also stored temporarily in the
receiver.
3. An additional feature - the ‘Battery Fail-Safe’ function:
as
soon as the voltage of the receiver battery falls below a value
of about 3.8 V, the throttle servo runs to idle in order to warn
the pilot that the airborne battery is almost flat.
If this should
happen, you must land immediately.
The following illustrations show the Fail-Safe menu for fixed-
wing models and helicopters, with fail-safe settings already
entered.
Each channel is listed individually. The first column covers the
fail-safe mode (Hold or F/S), which can be changed as requi-
red. To do this simply activate the appropriate field, and con-
firm the security query by pressing ‘YES’.
If you opt for ‘Fail-Safe’, it is then necessary to enter the cor-
rect settings for the servo positions. This is carried out by
moving the associated transmitter controls to the desired
position, and operating the (F/S-POS) field for that channel. In
each case the servo position you enter is displayed as a per-
centage figure. A security query is then displayed; if you con-
firm with ‘Yes’, the new Fail-Safe value is stored. This process
has to be repeated for all the channels which you have set to
‘F/S’ mode.
In the second column you can use exactly the same procedure
to program the Battery Fail-safe feature, separately for each
channel. The display changes from ‘OFF’ to ‘B.F/S’.
The warning position for the selected servo is entered using
the method already described; the value is displayed on-
screen in the form of a percentage. We recommend that you
set up the throttle or airbrake / spoiler servo for this warning
function.
It is possible to reset the Battery Fail-Safe function; this is
achieved by assigning a transmitter control to the function:
activate the appropriate field at top right of the screen. When
you do this, the switch select menu appears.
You have to mark the transmitter control or switch you wish to
use for this function. The set control is displayed on the gra-
phic screen. If you wish to reset the switch select function,
press the ‘NONE’ button.
The ‘On-posi.’ but-
ton field is used to
determine the direc-
tion of effect of the
switch. If you prefer
to use a transmitter
control instead of a
switch, you can also
program hysteresis
(a dead zone) and a
switch range (linear
or symmetrical) in
addition to the swit-
ching position. The
coloured graphics
make the procedu-
res virtually self-
explanatory: basi-
cally you just move
the transmitter stick to the desired position, and press the
‘Sel.’ (Select) field. The software then adopts the set position
and displays it.
The F/S settings necessarily vary according to the set model
type. For example, sensible settings for a model helicopter
would cause it to take up a stable hover; for a fixed-wing
model aircraft it should take up a broad turning pattern. The
basic requirement is that brief interference should trigger a set
of fail-safe settings which would automatically enable the
model to adopt an inherently stable flight pattern even when
not under the pilot’s control, until contact with the transmitter
is restored. If you select the throttle function, don’t set the
throttle value too low, otherwise there is a danger that the
motor will stop.
You can check the settings by switching the transmitter off and
observing the reaction of the servos connected to the receiver.
Note:
When you select a fixed-wing model aircraft or helicopter as
the model type, a fail-safe setting is automatically pro-
grammed for the throttle function. It is important to check
whether the default setting is correct for your application.
Change it if necessary, or set the function to HOLD mode if
you prefer.
46
