Skyview display of flap position (resolved)

[Harry]

I'm using an AircraftExtras FPS (flap positioning system) with Skyview and want to show flap position on the EFIS.
The system uses a Ray Allen POS-12 to control the flaps.  The instructions specifically say to not wire the potentiometer directly to the display device as well as their box.  It has a separate output for this purpose.  Problem is the output sends a variable voltage for flap position from 0 to 6 volts.  The Skyview instructions say that the input voltage should be from 0 to 5 volts.
I spoke with someone at Dynon a few weeks ago about this issue.  They recommended that I not connect it if the voltage is above 5.

Any ideas on how to correct this?  Would an inline resistor of some sort possibly work?

Harry

 

[mmarien]

Re: Skyview display of flap position

I'm using the FPS and have the output pin 11 wired to my SV. The voltage is less then 5V. My calibration file:

user_cal={
valid=1
name=FLAPS POSITION
num_points=4
point={
volts=2.49874
value=0
}
point={
volts=2.29713
value=10
}
point={
volts=2.06589
value=35
}
point={
volts=1.77456
value=70
}
}

If you are not sure about your configuration, connect a voltmeter to the FPS pin 11 and run the flaps through the full range to check the output.

 

[Harry]

Re: Skyview display of flap position

Thanks, but I already checked that.  I am getting 6.1 volts out of pin #11 when the flaps are at the full up position

Harry

 

[sandaville]

Re: Skyview display of flap position

You could use a simple 5 to 1.1 ratio potential divider to drop the voltage. Something like 100K and 22K resistors should work. Connect as follows:-

Join one end of each resistor together.
Connect other end of 100K resistor to Ground.
Connect other end of 22K resistor to your 6.1 volt source.
Check the voltage across the 100K resistor and it should be around 5V when flaps are full up. (for info the other 1.1V will be dropped across the other resistor)
If all OK connect the point where the 2 resistors are joined to your EMS input pin.
DONT FORGET TO INSULATE THE CONNECTIONS AND ENSURE THE EMS IS CONNECTED TO THE SAME GROUND AS THE 100K RESISTOR AND YOUR FPS.

 

[dynonsupport]

Re: Skyview display of flap position

Note that SkyView can't measure above 5V, but it won't damage anything at voltages that are slightly above like you're talking about. So the issue is that between 5-6V, you won't get any instrument movement.

 

[Harry]

Re: Skyview display of flap position

Got it fixed!
I don't know why I didn't think of it earlier, but I simply moved the connection point to the flap arm closer to the pivot point resulting in less movement of the potentiometer.
Re-programed the FPS and now getting 4.75 volts at full up flaps.

Thanks for the replies!

Harry