My understanding is that the reason the battery should not be
disconnected during engine running is that it is important that the
regulator sees a load. One way to help achieve this is for at least one
significant electrical load to be supplied direct from the regulator
output. Anyone with a dual electrical pump system already does this
with one of the fuel pumps but for those with a mechanical pump another
load could be used.
Nigel Charles
-----Original Message-----
From: owner-europa-list-server@matronics.com [mailto:owner-europa-list-
server@matronics.com] On Behalf Of josok
Sent: 05 August 2008 21:50
Subject: Re: Europa-List: Ducatti Rectifier/Regulator
Mine failed just over 150 h. It's mounted inside the panel, to keep it
out of the heat of the engine. I really do not believe the error rate
of this component is environmental heat related. It's more of a quality
issue. Some time ago there was a similar thread, and if i remember
correctly there was a German origin alternative offered.
Anyhow, in my case there happened more then bargained for. The red
lamp came during flight, and shortly after a low voltage warning. Since
i can switch everything over to the second power system, i was not
worried, and did the 3 hrs 30 mins leg to the rotax dealer as intended.
There the engine was checked for damage after the wheel up landing, and
i mentioned the probable regulator failure. However, the charge lamp
was and stayed out. During the test flight thereafter i noticed that
there was still no charge. My assumption was that the red lamp had
burned out, and that everything would be fine after i would have
replaced the regulator. That assessment was wrong, as later turned out.
After about one hour in the next flight, smoke appeared in the cockpit,
and i asked for an immediate landing at a nearby airport. In the 5
minutes it took to land the plane, the smoke started to vanish. The
smell was something i had smelled before, but could not immediately
place. Examination sho
wed that the large smoothing capacitor had cooked itself empty.
The sequence of events has been, that this regulator developed a
fault, and put AC current to the battery and capacitor. After a while
the 30 amp battery fuse had blown, with the result that the charge
control lamp does not light. After that fuse had blown, the full AC
power of the charging coils was released on the capacitor, which gave
way, causing an emergency landing.
Lessons learned: Do not keep flying with a red lamp on. Do not assume
anything, check and correct before the next flight. Having an
alternative system is great, but creates overconfidence on the
downside.
Question unanswered: There is text on the regulator: Do not take the
battery off line with a running engine. If you look at the Rotax
manual, that is exactly what the main switch or contactor does. Maybe
the regulator blew up dangerously when i tried to recycle the main
switch. Also a blown battery fuse takes the battery off line. On the
other hand, there is no fuse in the charge coil circuit. In this case,
the connector shows melting marks, and solder has dripped from the one
of the AC connector tabs.
In other words: There is no protection from defect rectifiers in the
regulator. IMHO there should be a fuse in the circuit too. Unless i get
contradictionary information, that fuse will be there after the next
service stop.
Regards,
Jos Okhuijsen
Visit - www.EuropaOwners.org
Checked by AVG - http://www.avg.com
8/5/2008 6:03 AM
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