backup for EMS - sharing engine sensors?

[Taigajoe]

I have installed a single D700 system. In case of hard failure of SV or EMS module during flight there is no chance to get any information about the engine - only the noise.

I am thinking hence about an active backup for EMS - i.e. with MGL Av. E3. My question: Is it possible to share all engine sensors between Dynon EMS and MGL Av. E3? I know it is a question of the input resistors. Has anybody a solution for sharing engine sensors?
Thank you!

Taigajoe

 

[dynonsupport]

People generally don't do this, considering the failure of the engine instruments as something that isn't critical to have backed up, not to mention the added the engineering, weight, complexities/failure modes having more instruments/wires/switches/sensors introduces.

The thinking is (and this is not Dynon's opinion, just what our customers typically tell us) that unless you have an exotic power plant, your ears can tell you everything you need to know to get back on the ground safely.

 

[Taigajoe]

Thanks for your answer. I have no exotic engine - it is a 912S. In general I agree with your or your customers opinion regarding a backup of EMS. But the reason why I am thinking about is that I am flying sometimes very long distances over the Sea - up to 6..8 hours. I am trusting in the quality of your products but sometimes is it better to have a second chance in the middle of nowhere. I can hear if the engine is running smooth - over the Sea it is always running rough - or I can estimate the rpm but I cannot hear the oel temperature. Therefore I am thinking about a backup solution.

 

[dynonsupport]

There is no way with us, or any other engine monitor to share sensors. By definition, you now have two instruments hooked to the same wire, so the failure of one instrument can cause the signal on that wire to be changed, leading to a false reading on the other instrument. You won't find any engine monitors out there that support multiple connections to the same sensor.

Also, sensors are not perfect and fail themselves, so your redundancy is not as great as you think it is if you have two things reading the sensors but only one sensor.

If you really require this data backed up, you absolutely need to install a second set of senders on the engine.

 

[Taigajoe]

Ok, there are a lot of things to consider. Thank you!