Wren 44 TurboProp Users Manual. Copyright Wren Turbines Ltd February 2008 Page 27
Mounting the ECU
The ECU can be mounted in any accessible position – people often use a hook & loop type strip.
The ECU has an LED (light emitting diode) next to the signal wire from the receiver and the data
display terminal socket, that shows its status when the terminal is not plugged in.
Once the remainder of the servos are installed and tidied the ECU can be set up with your radio.
Set up ECU (Engine Control Unit)
The ECU supplied is a special version of the FADEC Autostart ECU by Gaspar Espiell. It is a reliable unit
and is supplied programmed for the Wren44 TurboProp. The engine has already been set up and tested
using the ECU and the fuel pump, so there is only the radio to setup to get the engine ready for running.
Confirm you have connected the ECU input to the throttle channel of your receiver and the ECU data
terminal (display) is plugged into the ECU. Remove all rates, mixes and throttle travel settings in the
transmitter. The setup assumes the use of a transmitter with manual trims. If you have a transmitter with
digital trims it would be advised to check if a switch on the transmitter has been allocated the function of
“throttle cut” or “engine cut” which normally has the effect of producing the trim-down function. Check your
radio manual for this before you start.
As the display does not photograph well we have reproduced the display readings as a green box.
Turn on the transmitter and receiver. The opening screen should show as below: (If the temp’’ probe is not
connected it will show as 0’C). “T” = ambient temp’ (shown as 15’C but will be whatever you have locally at
the time).
Note there are four buttons along the bottom of the display
(^ v - +). The two left buttons move to the different screens
and the two right buttons are used to change the values
stored.
Press the 2
nd
from left button (v) to scroll down the menus until you find the one showing :
Press the right hand button (+) and the screen will change to:
On your transmitter, raise the throttle stick and trim to full. Ensure stick
is firmly against the stop.
Now holding the stick against the stop, press the right button (+) to set
the value into the ECU.
The screen will now change to:
Move the trim (or switch the “engine cut” switch to on) and throttle stick
back to zero and again press the right (+) button.
Trim Low
Trim Low
Trim Low
Trim Low
T=015’C
T=015’C
T=015’C
T=015’C
RPM 00000
RPM 00000
RPM 00000
RPM 00000
PW 000
PW 000
PW 000
PW 000
Transmitter
Transmitter
Transmitter
Transmitter
yes
yes
yes
yes
adjust
adjust
adjust
adjust
St
St
St
Stick Up Trim Up
ick Up Trim Up
ick Up Trim Up
ick Up Trim Up
(Full power)
(Full power)
(Full power)
(Full power)
Stick Down
Stick Down
Stick Down
Stick Down
Trim Down (Stop)
Trim Down (Stop)
Trim Down (Stop)
Trim Down (Stop)
