---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Fri 01/22/16: 15 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:15 AM - Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con (user9253) 2. 07:31 AM - Any news about Matt? (Robert L. Nuckolls, III) 3. 07:32 AM - Re: Engine Ground (Robert L. Nuckolls, III) 4. 08:12 AM - Re: Any news about Matt? () 5. 08:16 AM - Re: Any news about Matt? (Charlie England) 6. 08:43 AM - Re: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con (Ken Ryan) 7. 10:18 AM - Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con (user9253) 8. 11:13 AM - Re: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con (Ross Home) 9. 11:49 AM - Re: Engine Ground (Kelly McMullen) 10. 12:02 PM - Re: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con (Ken Ryan) 11. 02:22 PM - Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con (user9253) 12. 05:21 PM - Re: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con (Robert L. Nuckolls, III) 13. 05:28 PM - Re: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con (Robert L. Nuckolls, III) 14. 06:06 PM - Re: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con (GTH) 15. 07:47 PM - Wiring Diagram (H. Marvin Haught Jr.) ________________________________ Message 1 _____________________________________ Time: 07:15:45 AM PST US Subject: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con From: "user9253" 1. Over voltage protection. Bob Nuckolls made a demonstration board for an court trial. He made a movie showing what happens when fuses or circuit breakers are in series. If Bob is reading, maybe he can provide a link to that movie. It was interesting. Anyway, even a 10 amp fuse might blow before a 5 amp series breaker trips. The fuse needs to be slow blow and much larger than the circuit breaker. Or do not put protection devices in series. 2. Understand 3. The capabilities of an EFIS are amazing. 4. OK 5. The reason that I suggested using a smaller breaker for the output of the 20 amp dynamo is that in the event of a short circuit, a 20 amp breaker might not ever trip because the dynamo will struggle to put out that much current. The AC coils or regulator could overheat. Since the fuel pump is the only load and requires less than 10 amps, a larger breaker is not needed. Have fun with your project. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=452191#452191 ________________________________ Message 2 _____________________________________ Time: 07:31:59 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Any news about Matt? It has been some time since Matt's misfortune was updated here on the List . . . does anyone have some recent feedback to share? Bob . . . ________________________________ Message 3 _____________________________________ Time: 07:32:18 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Engine Ground At 08:09 PM 1/21/2016, you wrote: >I happened to be helping repair a Cessna 170-B and noticed the >engine ground was routed only about 4" aft of the rubber mounts and >attached to a tab on the motor mount in lieu of the firewall. This >saved a few feet of heavy wire and a few ounces. That was a common practice . . . waaayyyy back when . . . Bob . . . ________________________________ Message 4 _____________________________________ Time: 08:12:14 AM PST US From: Subject: Re: AeroElectric-List: Any news about Matt? I didn't dear asking, but since there were 2 messages from him meanwhile about list usage, I was assuming that he is back in the saddle and things are ok. Rumen ---- "Robert L. Nuckolls wrote: ============ It has been some time since Matt's misfortune was updated here on the List . . . does anyone have some recent feedback to share? Bob . . . ________________________________ Message 5 _____________________________________ Time: 08:16:38 AM PST US Subject: Re: AeroElectric-List: Any news about Matt? From: Charlie England On 1/22/2016 8:50 AM, Robert L. Nuckolls, III wrote: > > > It has been some time since Matt's misfortune > was updated here on the List . . . does anyone > have some recent feedback to share? > > > Bob . . . Here's a link to a VAF thread about Matt: http://www.vansairforce.com/community/showthread.php?t=133051&highlight=matt+dralle Last bit of info says that he's moved to a rehab facility. Bob Leffler mentions that the family has been updating their facebook page, but I'm a bit of a facebook luddite. Charlie ________________________________ Message 6 _____________________________________ Time: 08:43:12 AM PST US From: Ken Ryan Subject: Re: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con Thanks Joe. I will move the field wire for the 40 amp alternator away from the bus, maybe to the battery relay. That will eliminate the fuse, leaving only the 5 amp panel breaker on the over voltage/field circuit. I will downsize the 20 amp panel breaker for the 20 amp integrated generator to 10 amps for the reasons you stated. On Fri, Jan 22, 2016 at 6:01 AM, user9253 wrote: > > 1. Over voltage protection. > Bob Nuckolls made a demonstration board for an court trial. He made a > movie showing what happens when fuses or circuit breakers are in series. > If Bob is reading, maybe he can provide a link to that movie. It was > interesting. Anyway, even a 10 amp fuse might blow before a 5 amp series > breaker trips. The fuse needs to be slow blow and much larger than the > circuit breaker. Or do not put protection devices in series. > 2. Understand > 3. The capabilities of an EFIS are amazing. > 4. OK > 5. The reason that I suggested using a smaller breaker for the output of > the 20 amp dynamo is that in the event of a short circuit, a 20 amp breaker > might not ever trip because the dynamo will struggle to put out that much > current. The AC coils or regulator could overheat. Since the fuel pump is > the only load and requires less than 10 amps, a larger breaker is not > needed. > Have fun with your project. > > -------- > Joe Gores > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=452191#452191 > > ________________________________ Message 7 _____________________________________ Time: 10:18:41 AM PST US Subject: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con From: "user9253" Link to Bob's demonstration of a circuit breaker and fuse in series. http://www.aeroelectric.com/Reference_Docs/Accidents/N811HB_Feb2008_LA-IVp/03_Larger%20Fuse%20Hypothesis.wmv WMV file size is 87 MB -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=452198#452198 ________________________________ Message 8 _____________________________________ Time: 11:13:31 AM PST US From: "Ross Home" Subject: RE: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con With a download time of 11 hours, I think I will pass even though it looks interesting. Thanks for posting it though. Ross -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of user9253 Sent: Friday, January 22, 2016 10:16 AM Subject: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con Link to Bob's demonstration of a circuit breaker and fuse in series. http://www.aeroelectric.com/Reference_Docs/Accidents/N811HB_Feb2008_LA-IVp/0 3_Larger%20Fuse%20Hypothesis.wmv WMV file size is 87 MB -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=452198#452198 ________________________________ Message 9 _____________________________________ Time: 11:49:15 AM PST US Subject: Re: AeroElectric-List: Engine Ground From: Kelly McMullen Perhaps my memory is fading from the C-170B that I owned for 23 years and sold 18 yrs ago, but I recall the engine ground going to the firewall. The path between the battery, master and starter relays is so short on that plane that it won't matter much. The battery was on the right side of firewall with one or both relays on the battery box. The starter is less than 12" away, one of the old pull start models at the top center of the engine accessory case. The run to the panel buss is equally short. On 1/22/2016 8:27 AM, Robert L. Nuckolls, III wrote: > At 08:09 PM 1/21/2016, you wrote: >> I happened to be helping repair a Cessna 170-B and noticed the engine >> ground was routed only about 4" aft of the rubber mounts and attached >> to a tab on the motor mount in lieu of the firewall. This saved a few >> feet of heavy wire and a few ounces. > > That was a common practice . . . waaayyyy back > when . . . > > > Bob . . . > ________________________________ Message 10 ____________________________________ Time: 12:02:06 PM PST US From: Ken Ryan Subject: Re: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con One other thing I was wondering ... does it make any difference if the panel breaker on the integrated generator comes before or after the capacitor? On Fri, Jan 22, 2016 at 7:40 AM, Ken Ryan wrote: > Thanks Joe. I will move the field wire for the 40 amp alternator away from > the bus, maybe to the battery relay. That will eliminate the fuse, leaving > only the 5 amp panel breaker on the over voltage/field circuit. I will > downsize the 20 amp panel breaker for the 20 amp integrated generator to 10 > amps for the reasons you stated. > > On Fri, Jan 22, 2016 at 6:01 AM, user9253 wrote: > >> >> 1. Over voltage protection. >> Bob Nuckolls made a demonstration board for an court trial. He made a >> movie showing what happens when fuses or circuit breakers are in series. >> If Bob is reading, maybe he can provide a link to that movie. It was >> interesting. Anyway, even a 10 amp fuse might blow before a 5 amp series >> breaker trips. The fuse needs to be slow blow and much larger than the >> circuit breaker. Or do not put protection devices in series. >> 2. Understand >> 3. The capabilities of an EFIS are amazing. >> 4. OK >> 5. The reason that I suggested using a smaller breaker for the output of >> the 20 amp dynamo is that in the event of a short circuit, a 20 amp breaker >> might not ever trip because the dynamo will struggle to put out that much >> current. The AC coils or regulator could overheat. Since the fuel pump is >> the only load and requires less than 10 amps, a larger breaker is not >> needed. >> Have fun with your project. >> >> -------- >> Joe Gores >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=452191#452191 >> >> >> >> >> >> >> >> >> >> >> > ________________________________ Message 11 ____________________________________ Time: 02:22:34 PM PST US Subject: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con From: "user9253" > does it make any difference if the panel breaker on the integrated generator comes before or after the capacitor? It will work in either location. But I think it is best the way you have it pictured. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=452202#452202 ________________________________ Message 12 ____________________________________ Time: 05:21:13 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con At 09:01 AM 1/22/2016, you wrote: > >1. Over voltage protection. >Bob Nuckolls made a demonstration board for an court trial. He made >a movie showing what happens when fuses or circuit breakers are in >series. If Bob is reading, maybe he can provide a link to that movie. The specific video is at: http://tinyurl.com/ppdv5fg The sum total of the accident analysis can be seen at: http://tinyurl.com/msfmldj > It was interesting. Anyway, even a 10 amp fuse might blow before > a 5 amp series breaker trips. I've opened 20A fuses through 5A breakers >5. The reason that I suggested using a smaller breaker for the >output of the 20 amp dynamo is that in the event of a short circuit, >a 20 amp breaker might not ever trip because the dynamo will >struggle to put out that much current. I'm aware of NO engine driven power source that is capable of opening its own output protection. Fuses, breakers, fusible links and current limiters protect wires . . . nothing more. Further, that protection needs to be installed facing the probable source of energy feeding the fault. In our itty-bitty airplanes, this is almost ALWAYS the battery. Hence, alternator output protection goes as close to the battery as practical. It is robust enough to stay closed under most energetic output the alternator can produce. I've written about the "breaker designed to nuisance trip" that was built into tens of thousands airplanes . . . a 60A breaker on 60A alternator. In the case of feeder protection for a 10-20A PM alternator/rectifier-regulator, a 30A fuse or mini current limiter is not too big and it CANNOT be nuisance tripped by alternator output. If some failure puts the alternator itself at risk . . . so be it. Let the alternator smoke, protect the wires and go to plan-B. Bob . . . ________________________________ Message 13 ____________________________________ Time: 05:28:07 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con At 01:54 PM 1/22/2016, you wrote: >One other thing I was wondering ... does it make any difference if >the panel breaker on the integrated generator comes before or after >the capacitor? In anecdotal observations over the years, I am not convinced that these capacitors across the bus on ANY system serve a useful purpose. I think it is there because somebody thought it was a good idea waaayyyyy back when . . . and I might even have agreed with the hypothesis. But in several instances of bench testing, I've not been able to measure any beneficial effect for the capacitor being there. I'm building a drive-stand to run the B&C SD-8 series machines on my bench. I'm doing some design studies on the next generation of PM rectifier-regulators to be offered by B&C. The legacy capacitor included in virtually every PM alternator architecture will be examined in detail with a goal of putting numbers on its efficacy. Bob . . . ________________________________ Message 14 ____________________________________ Time: 06:06:00 PM PST US From: GTH Subject: Re: AeroElectric-List: Re: Rotax 914 Generator, Alternator, Starting and Fuel Pump Con /Le 23/01/2016 02:24, Robert L. Nuckolls, III a crit : / > / > > The legacy capacitor included in virtually > every PM alternator architecture will be examined > in detail with a goal of putting numbers on > its efficacy./ Hi Bob and all, About 13 years ago during the build of our project, I had the opportunity to conduct some experiments with the Rotax 914 alternator & voltage regulator. We discovered that the Rotax voltage regulator doesn't start delivering energy unless it is subject to some voltage from the battery or capacitor. My buddy Jerome (he is the expert) made an electrical analysis of the performance of the voltage regulator. He also assessed the thermal behavior of the regulator with his students. I published some info on Contrails ! http://contrails.free.fr/elec_ducati_en.php Our MCR 4S four seater - wired as per the 'Connection philosophy - is still going strong after 11 years of service. FWIW, -- Best regards, Gilles http://contrails.free.fr http://lapierre.skunkworks.free.fr ________________________________ Message 15 ____________________________________ Time: 07:47:53 PM PST US From: "H. Marvin Haught Jr. " Subject: AeroElectric-List: Wiring Diagram Bob - I am finally back on the wiring diagram for the Pacer project I have in my hangar. Some health and family issues have taken precedence in the past months, but I am finally now where I can address the wiring of my project. I have used the time to lurk on the Short Wing Piper site as well as others, and got this diagram from a thread on wiring diagrams this week. I thought I would have the group as well as yourself take a look at this schematic as a basis for my electrical system. According to what I understood from the thread, the diagram is very similar to the wiring schematic for a 1981 Super Cub. I am having trouble accessing some of the archived photos and files on the site, but when I get that problem solved, will compare the actual Piper schematic to this one, and will post it here if it is different. To any extent, from my study of this particular schematic, I think it should make a good starting point for my project. Please take a look an provide feedback as you see fit. M. Haught --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ------------------------------------------------------------------------------------- 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.