Brian, A lot of years ago I found myself over horizon to horizon thick
forest, somewhere near the Czech border with all my electrical
instruments showing no signs of electricity and my assumption was that
my 914 was running on the fuel left in the carb bowls Fortunately my
standard checking system found that both master and alternator switches
were off and order was restored before everything went quiet (I had just
returned my pee bottle to its place under my left thigh support and in
doing so had managed to catch the toggle switches with my trouser
bottom. I felt that I had to share this slightly embarrassing incident
with the Europa community via Matronics in the spirit of the club, and
Andy Draper pointed out that if my wiring was as per manual the 914
would continue as the first pump is driven directly from the alternator
before its output gets to the alternator switch. I have subsequently
deliberately switched everything off and found this to be true.
Which makes me wonder about the exclusion of 914s from the Lithium
battery approval. Clearly if your battery blows up you won't be able to
get started, but on the face of it if it happens in flight you can still
expect to get home, (assuming you can find the way!)
Regards, David Joyce, GXSDJ
On 2017-09-10 08:43, Brian Davies wrote:
> For those of you operating under the LAA system there is a Standard Mod SM
> 14337
that gives details of approved Lithium batteries. Just a note of caution when
using batteries with a Battery Management System (BMS) that automatically
disconnects the battery if over or under charged. The Rotax built in alternator
produces avionics damaging voltages when the battery is disconnected. An
overvolt
protection circuit should be fitted to guard against this.
>
> At the moment the Mod cannot be used for the 914 because it relies on a
> working
electrical system. The range of batteries will be updated as more data becomes
available from the manufactures. What has already become clear is that not
all lithium batteries are suitable.
>
> Brian
>
> G-DDBD
>
> FROM: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com] ON BEHALF OF Greg Fuchs
> SENT: 09 September 2017 20:30
> TO: europa-list@matronics.com
> SUBJECT: RE: Europa-List: Battery
>
> Paul,
>
> The ETX36C has been used successfully for years. The Rotax 914 charging system
needs to be slightly modified to bring the charging voltage into the range the
lithium battery likes (Jim and Heather brought that to my attention). A diode
on the 'C' terminal of the Ducati regulator is adequate to fool the regulator
into thinking the battery is at a slightly lower voltage than it actually is
and so it will up its charge voltage, placing the battery into proper charging
range. I think its 13.9 to 14.6 volts per the data sheet, if memory serves.
>
> This lithium battery has cell protection. It has internal circuitry that can
remove the battery from the circuit due to too low or too high voltages (i.e.
when it is overcharged or drained). A happily charged battery will not
disconnect
---From the airframe. It is wise to have a good metal battery box for these in
the unlikely event of a thermal fiasco. A thin Fiberfrax layer can likely do
wonders too.
>
> The weight savings is amazing.. When you hold them in your hand, they feel
> like
a fake toy battery, but they will spin the engine right up for sure.
>
> Greg
>
> -------------------------
>
> FROM: owner-europa-list-server@matronics.com
> [mailto:owner-europa-list-server@matronics.com] ON BEHALF OF Paul McAllister
> SENT: Friday, September 08, 2017 7:13 AM
> TO: europa-list@matronics.com
> SUBJECT: Europa-List: Battery
>
> Hi All,
>
> My trusty Odessey battery has died and gone to heaven (or wherever batteries
go).
>
> I am seeking peoples experience with the new style Lithium batteries, and in
particular what can be sourced in the US.
>
> Thanks, Paul
>
> [1]
>
> Virus-free. www.avg.com [1]
Links:
------
[1]
http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=emailclient
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