Motorglider avionics

[HL Falbaum]

I just got a DG800B, with Dittel Radio and S-Nav/GPSNav setup. The Battery
is 2 parallel 6v in series w/ 2 more parallel 6 v giving 12v 24 AH. As far
as I can determine this is the standard DG800 setup.

The former owner assures me that the avionics are not bothered by voltage
spikes when starting or shutting down the engine.

The GPS needs time at basline and uninterrupted recording after that for
badge/record flight. I don't want to sit on the runway, idling the engine
before takeoff. Our airport is not conducive to taxi out and go.

Has anyone in r.a.s.-land had a problem with starting the engine with
avionics on?

Thanks

--
Hartley Falbaum

[5Z]

No problem with my ASH-26E.

I have 2 12v/18ah batteries. One is is hardwired to the engine and a
panel switch to choose one or the other to run the avionics. I usually
run the instruments from teh 2nd battery, but not always.

After assembly, I energize the panel and all instruments are on for
30-60 minutes. I tow to the takeoff zone, start, warmup, and launch.
Never had a problem.

-Tom

[COLIN LAMB]

A problem can occur when a field is shut down. This might be a relay used
for starting the engine. When the field collapses, a spike can occur.
Often a diode is placed across the field (opposite to the normal flow of the
circuit) to prevent this collapse (which is opposite polarity) from causing
a problem. The relay is unaffected by this.

Colin

[Gary Evans]

I have a DG808, Cambridge L-Nav and GPS. I have always
turned the instruments on before starting the engine.


At 00:42 18 September 2005, Hl Falbaum wrote:
>I just got a DG800B, with Dittel Radio and S-Nav/GPSNav
>setup. The Battery
>is 2 parallel 6v in series w/ 2 more parallel 6 v giving
>12v 24 AH. As far
>as I can determine this is the standard DG800 setup.
>
>The former owner assures me that the avionics are not
>bothered by voltage
>spikes when starting or shutting down the engine.
>
>The GPS needs time at basline and uninterrupted recording
>after that for
>badge/record flight. I don't want to sit on the runway,
>idling the engine
>before takeoff. Our airport is not conducive to taxi
>out and go.
>
>Has anyone in r.a.s.-land had a problem with starting
>the engine with
>avionics on?
>
>Thanks
>
>--
>Hartley Falbaum
>
>
>

[[email protected]]

I had a Super Dimona (aka Katana Xtreme these days) and now have a
Stemme. In both cases, I have started and stopped the engine with
avionics on with no problem. Of course, one ship's behavior does not
guarantee another's as there can be difference such as a large
capacitor or other filter on the avionics bus to help cut down voltage
spikes.

On the other side of the equation, even though I have had no problems,
if there is time I will turn off whatever avionics make sense before
starting or stopping the engine (e.g., turn off the transponder before
starting the engine to taxi after landing).

Martin