---------------------------------------------------------- RotaxEngines-List Digest Archive --- Total Messages Posted Tue 09/29/09: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:41 AM - Re: Rotax 912 Charging Problem (rampil) 2. 06:07 AM - Re: Re: Rotax 912 Charging Problem (Bob Borger) 3. 06:11 AM - Re: Re: Rotax 912 Charging Problem (Pete Christensen) 4. 06:37 AM - Re: Rotax 912 Charging Problem (Catz631@aol.com) ________________________________ Message 1 _____________________________________ Time: 05:41:42 AM PST US Subject: RotaxEngines-List: Re: Rotax 912 Charging Problem From: "rampil" Hi Hugh, Yes, the latest install manual has a plot of output vs rpm which implies 20 A at 5000. However, the same manual also has a limit of 250 W on the alternator which at 13.5 is 18 A. In my original install manual, the limit was 17 A at 5800 rpm, derated to 16 A at 5500 rpm. To my knowledge, there has been no power output upgrade to the alternator since 2002 when my engine was delivered. Your problem seems to be completely explained by excessive load on the alternator and has nothing to do with the battery. Therefore, I may be crazy, but I am going to stand with my explanation given the limited info you supplied, and say that the new Install Manual is "generous" -------- Ira N224XS Read this topic online here: http://forums.matronics.com/viewtopic.php?p=265520#265520 ________________________________ Message 2 _____________________________________ Time: 06:07:34 AM PST US From: Bob Borger Subject: Re: RotaxEngines-List: Re: Rotax 912 Charging Problem Hello Hugh, I'll add my two cents to say that I agree completely with Ira. The stock alternator on the Rotax 9xx series engine is hard pressed to turn out more than 15 amps at 13.8 volts. And if you do try to run more than that through the Ducatti regulator the regulator will die. I suggest you sort out your power requirements to keep them under 15 amps for most of the flight so there some extra amps available to recharge the battery. Then you can add the landing lights and other power hogs at the end of the flight if they are needed. And find one of those Schumacher battery tenders that 'lectric Bob recommends and use it to keep your battery happy between flights. Check six, Bob Borger Europa XS, Rotax 914, Airmaster C/S prop On Tuesday, September 29, 2009, at 07:39AM, "rampil" wrote: > >Hi Hugh, > >Yes, the latest install manual has a plot of output vs rpm which >implies 20 A at 5000. However, the same manual also has a limit >of 250 W on the alternator which at 13.5 is 18 A. > >In my original install manual, the limit was 17 A at 5800 rpm, derated >to 16 A at 5500 rpm. > >To my knowledge, there has been no power output upgrade to the >alternator since 2002 when my engine was delivered. > >Your problem seems to be completely explained by excessive load on >the alternator and has nothing to do with the battery. > >Therefore, I may be crazy, but I am going to stand with my explanation >given the limited info you supplied, and say that the new Install >Manual is "generous" > >-------- >Ira N224XS > > >Read this topic online here: > >http://forums.matronics.com/viewtopic.php?p=265520#265520 > > ________________________________ Message 3 _____________________________________ Time: 06:11:58 AM PST US From: "Pete Christensen" Subject: Re: RotaxEngines-List: Re: Rotax 912 Charging Problem Hugh, I used the stock unit from Rotax. It is easy to install. I did add an aluminum heat sink thinking it would help keep things cool. Mine failed at about 400 hours. My regulator is behind my panel not in the engine area. Pete ----- Original Message ----- From: Hugh MCKAY III To: rotaxengines-list@matronics.com Sent: Monday, September 28, 2009 8:38 PM Subject: Re: RotaxEngines-List: Re: Rotax 912 Charging Problem Pete: What brand/type regulator did you have that failed? What type/brand did you replace it with? Hugh McKay --- On Mon, 9/28/09, Pete Christensen wrote: From: Pete Christensen Subject: Re: RotaxEngines-List: Re: Rotax 912 Charging Problem To: rotaxengines-list@matronics.com Date: Monday, September 28, 2009, 2:54 PM Had the same problem with my Kitfox III/912. Asked the same questions. Replaced the rectifier/regulator. Problem solved. Pete ----- Original Message ----- From: Hugh MCKAY III To: rotaxengines-list@matronics.com Sent: Monday, September 28, 2009 1:07 PM Subject: RotaxEngines-List: Re: Rotax 912 Charging Problem I have a Rotax 912 UL engine on an Allegro 2000 LSA. Recently I have had to replace my battery (12V 18Ah) because of it's inability to crank the engine. Prior to replacing the battery I noticed my combination Volt/Amp meter showed only 12 volts while flying. Usually the voltmeter shows about 13.5 volts at start-up while the engine is running on the ground and while flying. After replacing the battery, and starting the engine the voltmeter returned to 13.5 volts. However, when I began to close certain circuit breakers engaging the front landing light, the two wing tip landing lights, the two wing tip strobes, and the nav. lights I noticed the volt meter dropping back each time I engaged one of the breakers until finally the volt meter again was indicating only about 12 volts just as before. I have a "no charge" red light in the battery charging circuit that comes on if the battery is not being charged while the engine is running. This light normally does not come on unless the engine is at very low rpm ( aprx.1400 rpm). This is not normal for my engine for my idle speed is set at 1800 rpm. I do not know why the voltage is dropping each time I close the breaker for lights described above, or what may be causing the voltage drop. I know I have a good battery, but I don't know if my regulator is going bad, or if there may be aground some where, or somthing else. Can anyone shed any light on what may be causing this? The engine has only 255 hours on it and I have not had any other problems with the engine. Any help would be greatly appreciated. Hugh G. McKay III Allegro 2000 Rotax 912 UL N661WW hgmckay@bellsouth.net href="http://www.matronics.com/Navigator?RotaxEngines-List">http://www. .matronics.com/Navigator?RotaxEngines-List href="http://forums.matronics.com">http://forums.matronics.com href="http://www.matronics.com/contribution">http://www.matronics.com/c ist" rel=nofollow target=_blank>http://www.matronics.com/Navigator?RotaxEngines-List et=_blank>http://forums.matronics.com llow target=_blank>http://www.matronics.com/contribution ________________________________ Message 4 _____________________________________ Time: 06:37:54 AM PST US From: Catz631@aol.com Subject: Re: RotaxEngines-List: Rotax 912 Charging Problem Hugh, I had a similar problem with not enough voltage. I have a Monroy traffic alerter in my aircraft (a GOOD thing !). It monitors your buss voltage when it is not detecting other aircraft. The female voice alerted me to "low voltage" and sure enough the gauge confirmed it. I removed the regulator and cleaned each of the terminals in the hope that it might be corrosion. That did the trick and I now have normal voltage. You might give that a try before buying another regulator. They are expensive. Dick Maddux Fox 4 Pensacola,Fl ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message rotaxengines-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/RotaxEngines-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/rotaxengines-list Browse Digests http://www.matronics.com/digest/rotaxengines-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.