Engine Start and D180 Power Interuption

[zimzeus]

Here's the engine start sequence...1)split master switch-Batt on. 2) Avionics switch on(boots up Dynon DEK180 only) 3) Engine start switch... to start.
Here's what happens...power to D180 is shut-off(blank screen) and D180 reboots when ignition switch is released
Is this normal or is something wired wrong ??
PS- I don't believe a internal Battery back-up is installed

Thanks ZMAN

 

[PhantomPholly]

If you don't have the battery backup installed, then two situations can cause the Dynon to re-boot:
1) Interruption of the power to the Dynon
2) System voltage falling below about 10v

Since my D180 is both my primary flight instruments and my EMS, I thought it well worth the extra money for the battery. Without that, in the event of electrical failure you don't know if another problem (like an engine fire) is occurring which might require you to shut down the engine.

The extra money could save your life. Caveat Emptor.

 

[zimzeus]

Are u saying that when u start your engine your D180 stays powered up all the time when the starter is cranking ?

 

[PhantomPholly]

Are u saying that when u start your engine your D180 stays powered up all the time when the starter is cranking ?

Yes - I have the internal battery, but I think my system voltage does not fall low enough for it to switch over.  I don't recall noticing it switching to internal battery power - it would give an alert for low voltage.  But, that is exactly the sort of thing I'm looking for on start, because that would be a sign that either my starter or battery is getting weak.

In any event, I would want to see all my instrument readings during startup - you might have only seconds to avert a real disaster if you get a fire on startup!  That is why I personally would not consider an EMS which does not function irrespective of battery voltage.

 

[dynonsupport]

zimzeus - This is normal if you do not have the internal battery installed. Basically, the FlightDEK-D180 needs about 10Vdc to operate. While you're cranking, the voltage can briefly dip below the minimum voltage. The internal battery prevents this behavior because the Dynon unit can briefly switch to it during the low voltage.

This behavior will not damage the Dynon, though.

 

[bertrand]

I had a similar behavior even after starting  up . Last week ,my D180 began to reboot  after 5 mn of running.My internal batterie was flat because I had to change the plane batterie and let the plane without voltage for a long period of time (2months) .

Is is the reason ? The voltage is normaly around 13V when the engine is running . Does  fluctuations on the output voltage ( Rotax) can be responsible for the reboot ?

I had no choice but  to interrupt my fligth and recharging the internal batterie but I still dont know if the problem is resolved.

regards

Bertrand

 

[PhantomPholly]

Bertrand,

What version of the firmware do you have loaded? Do you have the "keep alive" wire connected?

There were charging issues with older versions, and the keep alive is no longer recommended. I don't think 2 months should be long enough for a fully charged battery to discharge.

 

[bertrand]

Hello PhantomPholly

I don't remember the version number but my D180 just came from factory this summer because of stability problems ( the horizon was turning around in grey color). So I assume that it has a recent version.

I have the keep alive wiring.

It seems that when the internal battery has been charged a little the D180 doesn't reboot because before my flight I connected the principal battery for around 2 hours and the D180 stayed ok for 5 mn (and then turned of and began to reboot ). So during these 2 hours the keep alive worked to charge the dynon battery .

Bertrand

 

[PhantomPholly]

Recommend you do check your firmware version and make sure it is at least 5.0.

Dynon no longer recommends using the keep-alive line - disconnect it.

Then give the unit an overnight charge with a charger (a laptop computer transformer is usually 16-20v, and should do nicely). Check the internal battery voltage after disconnecting it. If it is now up to the recommended voltage (check the manual, or previous posts here) then you should be good to go.

Following all that you should not have any loss of EMS functionality during engine start.

 

[dynonsupport]

Well, first of all, we no longer recommend that you connect the keep alive wire. So disconnect that first and see if that changes anything.

Next, voltage fluctuations should not cause reboots unless they dip below 10V. If you're talking about the unit rebooting during engine start, that is expected behavior if you do not have a battery (of you have one and it is dead).

 

[bertrand]

Thanks for your answer . I'll disconnect the keep alive wire.

The rebooting problem was not during engine start but at least 5 mn later ( during taxiing) .The average voltage is usually over 10V (around 13,4V) that the reason why I was thinking of fluctuations .

Those fluctuations with Rotax equipment are noticed on the AMP measurement ( see posts on this subject) , so I guessed it was also the case for the voltage.

Bertrand