---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 12/25/21: 1 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:33 AM - Sv: ULPower Alternator/Regulator (Yahoo Mail) ________________________________ Message 1 _____________________________________ Time: 04:33:24 AM PST US From: Yahoo Mail Subject: Sv: AeroElectric-List: ULPower Alternator/Regulator Hi! Here is what ULPower says about their regulators capacity to handle failure s. The capacitor is key.... This is from the 520T manual available on net. The 30 Amp installation migh t be different, but is also available online. "The ECU needs a stable DC output . If the battery fails, or there is an op en contact inside, the buffering characteristics from the battery fail also . Such a situation may result in an unstable power supply to the ECU. Ther efore, we strongly recommend the installation of a genuine ULP capacitor (t his capacitor is able to cover for the big amount of amps coming from the a lternator/regulator) parallel on the battery. Likewise, a failure of the RR may result in an erratic power output, which is buffered by the battery and capacitor." Best regards Gjermund Westad ________________________________ Fra: owner-aeroelectric-list-server@matronics.com p=E5 vegne av Sebastien Sendt: l=F8rdag 25. desember 2021 05:23 Til: aeroelectric-l. Emne: Re: AeroElectric-List: ULPower Alternator/Regulator As Dan already posted, the alternator is permanent magnet. I was wondering more if anyone knows if the voltage regulator has any over- voltage protection included. ULPower are apparently very good about respond ing to inquiries so I will send them an email and post the reply to this li st. In any case, the electrical system on the aircraft in question has already been installed but was designed by a highly qualified and experienced elect rical & robotics engineer with no GA aircraft knowledge. The aircraft owner sent me the diagram so that I could admire it but a quick and dirty FMEA s howed some problems. A review of the manufacturer's instructions lead me to suggest that they rewire it to conform with those instructions but since t he alternator wiring already includes a current limiter and a solenoid I th ought it would be appropriate to leave those in rather than create the prob lem Joe pointed out vis a vis shorted b lead.1 If I can get permission I wi ll post the schematic to the list; notwithstanding its problematic features it's quite a work of art. Regards, Sebastien On Thu, Dec 23, 2021 at 2:11 PM Robert L. Nuckolls, III > wrote: 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 protectiv e 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.