Red cube fuel flow sensor not indicating

[Eric_Greenwell]

The Red Cube was installed in the plane when I picked it up in Mar 2014, but none of the screens had a fuel flow widget on them, and I never checked the fuel flow setup.

-I recently added a fuel flow widget to one of the screens, but it indicates 0.0 all the time.

-The wiring is correct at the sensor (black-black, white-yellow, red-red), but I didn't trace back to the C37 plug.

-Sensor Debug shows zeros for the Raw data at all times (even with the engine running), and 80000 for the calibration.

-Fuel pressure reads properly

What is suggested for tracing the problem?

 

[Dynon]

First, go to the EMS pin mapping and makes sure that fuel flow is configured on pin 14 (this is the nominal /by the book way to set it up). Next, the default K-factor is usually 68000, so I'd change that back. If that doesn't fix things, do trace each of the wires to the 37 pin connector.

 

[Eric_Greenwell]

First, go to the EMS pin mapping and makes sure that fuel flow is configured on pin 14 (this is the nominal /by the book way to set it up). Next, the default K-factor is usually 68000, so I'd change that back. If that doesn't fix things, do trace each of the wires to the 37 pin connector.

- Fuel flow is configured on pin 14
- Did not change K factor, as accuracy isn't a problem right now
- I determined the cube's white signal wire has continuity to C37/pin 14
- The black wire is grounded
- The red is supplying 11.99 volt
- The signal wire has 3.3 volts with SkyView on and the engine off

That leaves the EMS, which seems to be working on everything else, or the Red Cube. What is the next step?

 

[rvator51]

Another thought is to export your sensor logs and show the fuel flow widget setup from the sensor logs  here so the forum readers can check if it looks like it is configured correctly.

 

[dynonsupport]

The best test here is to take the white wire and tap it to ground. You can do this by hand with an alligator clip or something, with or without the red cube attached, as long as you see 3.3V on that wire.

If the EMS is working, this will cause flow to show up on the EMS. Just a tap or two a second will work. Then you know it's the red cube.

 

[Eric_Greenwell]

Another thought is to export your sensor logs and show the fuel flow widget setup from the sensor logs  here so the forum readers can check if it looks like it is configured correctly.

The attached picture shows the Sensor Debug Data during a flight. Just zeros show for the fuel flow, so I assume it's the signal, not the widget setup. I'll try the tapping the white wire to ground in the next day or two; also get the widget setup in case I'm wrong about that.

 

[Eric_Greenwell]

The best test here is to take the white wire and tap it to ground. You can do this by hand with an alligator clip or something, with or without the red cube attached, as long as you see 3.3V on that wire.

If the EMS is working, this will cause flow to show up on the EMS. Just a tap or two a second will work. Then you know it's the red cube.

I wish I'd known this method in the beginning, because it was quick and easy to do. When I did it, the sensor debug page showed pulses coming in, and the fuel flow widget showed a gallon or so flow. Since that's all working, it appears the problem is with the Red Cube.

Now what? I believe the aircraft dealer bought the Cube from Dynon, and had it installed with SkyView, EMS, Dynon radio, etc. I've had the plane less than a year, so I assume it's covered by a warranty. Who gives me a new cube and pays for the installation?

Ideally, someone sends me a cube Real Soon Now, I take it to Aircore in Arlington later in March, they do the annual, replace the Red Cube, and I or they return the non-functioning one to Dynon. Or maybe Dynon could get it to Aircore before I fly over there from Richland.

 

[Dynon]

Hi Eric,

Get in touch with our support department directly at 425-402-0433 or support at dynonavionics dot com and we can help get you sorted out.

 

[swatson999]

If the aircraft is Experimental, you can do the replacement yourself, of course, instead of waiting for annual inspection.

 

[Eric_Greenwell]

If the aircraft is Experimental, you can do the replacement yourself, of course, instead of waiting for annual inspection.

It's an S-LSA glider, so it can use Dynon equipment, but I'm not allowed to do that kind of work. Now you might be wondering why it has a fuel flow transducer if it's a glider; well, it's what we glider folks call a "touring motorglider", as it combines good airplane qualities (two seats, 110 kt TAS cruise, 110 lbs baggage) with decent glider qualities (30:1 glide ratio).

http://www.phoenixairusa.com/

 

[jakej]

Hey Eric

Can you guess what this glider is? ;D ;D

 

[Eric_Greenwell]

Well, it looks Australian to me, but that one only had two engines! This one looks much more complicated, and I can't recognize the glider with the little bit of it in the picture. Will it have SkyView in it?

 

[jakej]

Asw20 with 3x Amt jets, only one in existence I believe - a lot of wires for me to connect for such small engines. No Skyviews on this one but I am firing SVs on his Glasair super II RG as part of a complete install at the moment

Jake J