EMS / FT60 voltage issue

[wolf243_pl]

I have a FT60 fuel flow transducer mounted in my plane but get constantly 0 reading in the Dynon HDX.
Pin 14 is mapped and the calibration is set. The transducer is connected to the EMS-220 with the correct pins (13, 14, 15) but I measure only 7,95V on the red cable comming from pin 15.
According to the instruction the pin supoused to give 12V !?
I thought this was the reason the transducer is not working at all .

But recently I gave it 12V from another source and still had no reading in the HDX. I've looked at the debug file while the engine was running and there where only zeros.
So it makes me wondering maybe the "cube" is broken ?, but on the other hand the voltage on pin 15 is too low.
Could it be that the EMS gets too low voltage and therefore is not working properly? all other sensors connected to it are working fine.

 

[maartenversteeg]

I think that voltage output of the EMS is normal, but I will measure on my plane to see what exact value I get, and report later today. Also note that the output of the FT60 are pulses for a certain quatity of fuel measured so you can't just measure a voltage at the output of the sensor

 

[airguy]

The FT-60 does not send a "voltage" to indicate fuel flow, it sends a pulse connecting to ground for a very short period of time each time the turbine wheel inside the FT-60 spins and breaks an IR light beam internally. You can simulate this by taking the signal pin on the EMS and tap it to ground quickly by hand - you should see a fuel flow signal on the Dynon. If you are not getting a fuel flow "pulse" signal from the FT60, you need to check the power and ground to the FT60, and then check to make sure the turbine wheel inside is turning freely. Blow through (lungs and breathe - NOT compressed air) and see if you get a pulse output on the Dynon.

You cannot open the FT-60 - there are very tiny wires that are potted internally and you will break them when opening the unit. If someone in the past has tried to open the unit, then that is your problem.

 

[maartenversteeg]

NO my memory was wrong, I actually measure 13.4 volt on the 12 Volt sensor supply out of the EMS with two FT60 cubes connected

 

[wolf243_pl]

I've tried to simulate the "cube" per instructions and the fuel flow came alive ! That shows the EMS is working fine.

So I conected a new "cube" that I happend to have and its showing fuel flow after blowing in it !! even the low voltage is no issue anymore

Only thing left to do is to install the new "cube" and enjoy flying . Thanks a lot !!

 

[airguy]

First check your old cubes for power, ground, and signal wire problems - you might not have dead cubes, just a bad connection on a wire.

 

[wolf243_pl]

Finaly yesterday had some time to remove the old and install the new one. As far as I can tell (without openning it) the connections on the old one are fine , the turbine wheel inside is spinning freely - but the cube is not working.

Im glad that the new one is !

It needs propably some calibration. I had no daylight anymore to fly it so I just ran the engine for few minutes to verify everything is OK ( strangely for me there was little diffrence in FF at 1100RPM - 3,7 at full rich and 3,0 very lean - in my DA40 it goes as far as 1,7 gal/h - both are lycoming IO360).

Need to empty and refuel the tanks to see the diffrence in calculation

 

[jakej]

"Need to empty and refuel the tanks to see the diffrence in calculation " ?

Surely you meant a different method ? Fuel Computer cal is done by burning fuel etc

 

[wolf243_pl]

Sorry for the menthal shortcut

What I meant was I have to check the diffrence between real fuel burn and the calculation made by the computer based on FF.

And if its too much off , then change the value in sensor calibration menu.

 

[tniel7331]

I have a FT60 fuel flow transducer mounted in my plane but get constantly 0 reading in the Dynon HDX.
Pin 14 is mapped and the calibration is set. The transducer is connected to the EMS-220 with the correct pins (13, 14, 15) but I measure only 7,95V on the red cable comming from pin 15.
According to the instruction the pin supoused to give 12V !?
I thought this was the reason the transducer is not working at all .

But recently I gave it 12V from another source and still had no reading in the HDX. I've looked at the debug file while the engine was running and there where only zeros.
So it makes me wondering maybe the "cube" is broken ?, but on the other hand the voltage on pin 15 is too low.
Could it be that the EMS gets too low voltage and therefore is not working properly? all other sensors connected to it are working fine.

Tap on the fuel flow sensor and have someone watch. If it reads anything the sensor is bad. It works like a paddle wheel with a pick up as it spins. I've replaced 1 in 3 years and about a dozen Acft

 

[tniel7331]

Engine not running. Just power on. Also if it's off blow some air through it (don't tell dynon I said this ) sometimes a little dirty fuel gets by especially if fresh install and freezes up the action