Rotax 914 engine sensors

[JohnH]

I am planning an SV installation with a Rotax 914. Will the UMA N1EU07D differential fuel pressure sender work with the Dynon EMS 220? If not what fuel pressure sender should I order?
Should I order the Rotax 912 EMS sesor kit and simply add the UMA fuel pressure sender?

 

[dynonsupport]

The UMA differential pressure sensor is not technically supported today, but will be, likely in the 3.0 release. We don't have plans to stock the sensor ourselves, so yes, you would need to purchase it separately.

 

[JohnH]

Thanks for the answer. I don't mind purchasing it separately, but the real issue is that I need to get it working correctly with the SV. I will most likely ask for help in a few weeks when all the goodies arrive.

 

[JohnH]

It does seem odd to me that the Rotax 914 is not well supported. I have found this with AFS and when doing research on the Garmin G3X. Are there that few 914 installations?

 

[dynonsupport]

We do find that there are not enough 914 installs for us to stock the kits for them ourselves. But the SkyView system was designed with the 914 in mind and supports the differential fuel pressure sender, return fuel flow sender, and boosted MAP sender that a 914 needs, so we do our best to support it fully.

We do have the file you need to use the UMA differential fuel pressure sender right now so if anyone needs it go ahead and ask. It will also be part of the 3.0 release as mentioned.

 

[Hasbroucka]

Does the UMA differential pressure sensor then provide MAP and Fuel pressure reading on the EMS? or does it only provide the differential (carburator, relative fuel pressure)?

 

[Hasbroucka]

the 914 fuel pressure will run 3psi up to 25psi, depending on boost levels, and the MAP will run 0 to 20 psi (0 to 40in Hg)depending on RPM and boost levels.

Can I use a Dynon fuel injected fuel/fluid pressure sensor for fuel and one Dynon MAP sensor for MAP and overlay or closely place the two gauges so that i can see the differential pressure?

If yes, then would there be a way to configure the EMS to alarm if the fuel pres. ever goes less than MAP plus 4in Hg?

however we do it, it is helpful to have MAP and fuel pressure, I personally do not care if it is differential fuel pressure or total, as long as it can be presented in a manner that displays the differential.

 

[Dynon]

The UMA differential pressure measures the Rotax-specified fuel pressure against air box pressure, which is the thing you care about.

 

[Hasbroucka]

I think you are saying that it will provide One reading, differential between the two points.

Could you respond to my questions in Reply 6 please?

 

[Dynon]

Yes, you get one reading, which is fuel pressure, but is measured as Rotax specifies (against the air box pressure)

There isn't a way to set a conditional alarm like you're asking about.

You can put your MAP and fuel pressure sensor readings next to each other on the SkyView Engine Page, but, note that MAP is absolute pressure, while fuel pressure is gauge or differential pressure.

 

[pier]

Good morning,
I'd like to install a pressure sensor in the airbox of a 914 and read the signal on a Skyview system, what kind of sensor I need?
Thank you very much for your support P.

 

[Dynon]

What you're really after as an operator is the fuel pressure with respect to the airbox: See page 7-39 of the latest version of the SV Installation manual, excerpted below:


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Rotax 914 Differential Fuel Pressure Sensor
The fuel pressure sensors that Dynon Avionics sells are not suitable for use with the Rotax 914 engine, as Rotax specifies that fuel pressure on the 914 engine be measured with respect to the air box pressure. All fuel pressure sensors sold by Dynon Avionics are only capable of measuring fuel pressure against ambient air pressure.
The UMA N1EU007D sensor is a third-party differential pressure sensor which measures fuel pressure with respect to air box pressure as required by the 914 engine. This sensor is not supplied by Dynon Avionics, but it is supported by SkyView.
Install the differential fuel pressure sender in an area convenient to the connections on the engine. The mounting threads are 5/8-18. Connect side of sender marked with a “W” to the fuel line close to the carburetors. Use 1/8-27 pipe thread fitting. Connect the other side of sender to the air box. This can be done by inserting a “T” in the carb vent lines that go to the air box. Use a 1/8-27 pipe thread, barbed insert into the sender. Make sure all fittings on the air box lines are tight using spring clamps or tie wraps.
SV-EMS-220/221 Installation and Configuration
7-40 SkyView System Installation Guide - Revision P
Connect the red wire to EMS pin 15 (12V power). Connect the black wire to ground (an SV-EMS-220/221 ground is appropriate). Connect the white wire to any of the “C” type inputs on the SV-EMS-220/221 module - pins 8, 22, or 31 only.
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If you're after the airbox pressure with respect to ambient, you can fit any of our Kavlico pressure sensors to easily get air box pressure (gauge pressure). I'm not sure what the boost profile is for the 912, but you'd probably want either the 5 or 15 PSI sensor.