---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 12/23/21: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:01 AM - Re: Flashing on One side Ceases after a Minute or so (George Nielsen) 2. 09:18 AM - ULPower Alternator/Regulator (Sebastien) 3. 11:34 AM - Re: ULPower Alternator/Regulator (user9253) 4. 02:01 PM - Re: ULPower Alternator/Regulator (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 12:01:48 AM PST US Subject: AeroElectric-List: Re: Flashing on One side Ceases after a Minute or so From: George Nielsen Glen, thank you for your reply. Indeed this unit has been dormant for a few years. I reckon that I will have to switch it on regularly. George > Time: 11:50:09 AM PST US > From: GLEN MATEJCEK > Subject: AeroElectric-List: Flashing on One side Ceases after a Minute or so > > > Howdy- > Has the unit been sitting dormant long? I seem to recall from some long time ago > that there were electrolytic capacitors in that power supply that could go > bad if they sat unused for long periods. There was the possibility of recovering > them if the went through repetitive power up cycles over time. So, you might > just try powering on every so often to see if it starts functioning properly > again. I > ________________________________ Message 2 _____________________________________ Time: 09:18:06 AM PST US From: Sebastien Subject: AeroElectric-List: ULPower Alternator/Regulator Does anyone have experience with this system? My friend is installing a UL350 Engine and their wiring diagram and instructions specify no protective devices between the alternator and the battery. Does anyone know if this alternator/regulator combination can suffer from an overvoltage event? Or is the regulator fault tolerant? Regards, Sebastien ________________________________ Message 3 _____________________________________ Time: 11:34:35 AM PST US Subject: AeroElectric-List: Re: ULPower Alternator/Regulator From: "user9253" When the alternator "B" lead shorts to ground, the pilot will be lucky if there is no fire when the "B" lead turns white hot and melts from high battery current. Now that the alternator is no longer connected, the electrical system relies on the battery. But half of the battery energy has already been depleted melting the "B" lead. Either a large fuse or fusible link should protect the "B" lead from excessive battery current, regardless of what UL Power says. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=505365#505365 ________________________________ Message 4 _____________________________________ Time: 02:01:16 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: ULPower Alternator/Regulator At 11:16 AM 12/23/2021, you wrote: >Does anyone have experience with this system? My friend is installing a >UL350 Engine and their wiring diagram and instructions specify no protective >devices between the alternator and the battery. Protecting b-lead wiring from hard faults within the alternator itself is a legacy protocol in T/C aircraft since the first Ford alternator was bolted to a Cessna (approx 1964). However, LOTS of automotive applications tie the alternator b-lead right to battery (+) (like my '87 GMC) with some later models adding a fusible link at the battery end (like the 97 Chevy I worked on last week). What kind of alternator is on the UL350, wound field or permanent magnet? >Does anyone know if this alternator/regulator combination >can suffer from an overvoltage event? Or is the regulator >fault tolerant? There is NO alternator system immune to OV events. Probability, severity and risk run the gamut from a little puff of smoke to a major incendiary event. That needs to be sorted out in a failure mode effects analysis with appropriate prophylactics incorporated. As supplier of the system, the engine manufacturer SHOULD have conducted those studies and published well considered protocols in their manual . . . unfortunately, few engine suppliers have any notion of what that process entails. The usual answer to a query on the matter is: "we've got xxxx of these flying with no reported events of noteworthy magnitude." For this List to offer any more considered advice, much more data are needed as to system characteristics. The SAFE thing is to incorporate b-lead and ov protection as a matter of policy . . . it's light, cheap and better to have it and not need it as opposed to needing and not having. Bob . . . Un impeachable logic: George Carlin asked, "If black boxes survive crashes, why don't they make the whole airplane out of that stuff?" ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-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/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-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.