The WREN MW54 MkIII turbo-jet

[Mister-Sheep]

Hi everyone. I am currently undertaking tests on a WREN MW54 MkIII turbo-jet. I have loaded the results from FADEC into my computer and have noticed the 'throttle' channel seems to pulse 0,191,0,191,0,191... when the engine is not running. Does anybody know what this is? and what do all the throttle numbers represent? All i know is that the highest reading is 988 at full power but I have no idea what this represents.
Cheers everyone
J.Ryan

[Turbo-Tom]

The pump value represents the PWM ratio of the 10 bit PWM module that controls power to the pump motor. A pwm setting of 988 means that the pump motor receives full battery voltage 988 out of 1024 "time slots" (for a ten bit PWM). Yet the pulsing while the engine is shut off seems a little strange to me. Is the pump turning over? It may also be an effect of the FADEC PC software program. I found it behaves a little "peculiar" here and there. Especially when saving and restoring FADEC settings, it seems to make mistakes.

Another thing to observe is that at full power, the PWM shouldn't be too high with a FADEC or you may get into trouble with flameouts. A PWM of 988 is already quite at the edge. I wouldn't go beyond 800 or the margin for pump wear or other tolerances may already be too small. You may try adding a cell to the pump battery, this should solve the problem (that is if one arises). Also, acceleration of the engine will benefit from the higher voltage.

The FADEC is a nice system and will operate your engine very smoothly. Especially the starts are very good, no flames and low temperatures. But the system is not without its flaws and adjusting it properly to get the best performance from your engine may be quite tricky.

If you've got further questions, unfortunately I cannot reply until Monday next week since I'll just start off towards the Villesse Jet meeting in Italy.

Cheers,
Tom

[ROSSMANS]

Hi everyone. I am currently undertaking tests on a WREN MW54 MkIII turbo-jet. I have loaded the results from FADEC into my computer and have noticed the 'throttle' channel seems to pulse 0,191,0,191,0,191... when the engine is not running. Does anybody know what this is? and what do all the throttle numbers represent? All i know is that the highest reading is 988 at full power but I have no idea what this represents.
Cheers everyone
J.RyanWhy dont you e-mail Sara at WREN Turbines and get the gen you require. :confused: