---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 02/26/19: 4 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:08 PM - History of the E-Bus (Robert L. Nuckolls, III) 2. 12:10 PM - List subscription problems? (Robert L. Nuckolls, III) 3. 01:19 PM - Re: List subscription problems? (Christopher Cee Stone) 4. 07:17 PM - Buy [5Pieces] Samsung Galaxy New S10/S10+ 128GB $3,495CAD (trptioip) ________________________________ Message 1 _____________________________________ Time: 12:08:18 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: History of the E-Bus One dark and quiet night, a long time ago, I got a call from one of my California seminar attendees wrestling with a Load Analysis/FMEA for his Long-Ez project. He cited a seminar discussion about the value of Plan-B protocols for dealing with single failure of a really important component of the electrical system. A plan that would prevent a failure from becoming the source of his personal 'dark-n-stormy-night' story . . . or worse yet . . . root cause of events that produced an NTSB accident report on his demise. His airplane was fitted with an SD-8. 8+ Amps in cruise rpm. He was interested in long endurance flights over unfriendly terrain limited to daytime only. No lights on the aircraft. After some discussion we settled on a design goal for powering a minimally useful list of electro-whizzies, battery only for duration of fuel aboard. I forget the exact numbers but one of the sticking points of our study was the battery contactor . . . 0.8A of constant draw while energized . . . enough energy to operate two solid state radios . . . just sitting there using that energy to do nothing more than get warm. During that discussion, we concocted the idea of an ENDURANCE bus to (1) power a minimally useful equipment list, (2) power additional items easily turned off to shed load and (3) have a battery energy path around a de-energized battery contactor. I think it was Figure Z-1 back in those days but the outcome of the conversation added a bus structure diode fed from the main bus and switched feed from the battery bus. As I recall, we crafted a plan-B for his project that would offer 5+ hours of battery only operations with a battery offering only 80% of nameplate capacity. I made a mistake in calling it the ESSENTIAL bus. Others wanted to call it the EMERGENCY bus. Later I reasoned that the sole purpose for installing the E-Bus was to prevent loss of alternator or battery contactor from becoming an emergency. Easily switched gizmos of lesser utility might also be driven from this bus; easily managed by performing a check-list driven transition to Plan-B. Over the years, some builders have opted to add switches to 'protect' avionics. Some persist in the EMERGENCY/ESSENTIAL nomenclature . . . which is fine. But understand that the E-Bus has roots in a design goal to maximize the utility of a very limited electrical system while reducing risk. The E-bus is still practical for architectures like Z13/8 where the second engine driven power source is small (cheap and light too!). Z13/8 offers an unlimited duration for en route energy supplied by the SD8 and practically unlimited energy for descent and approach to landing by taping battery reserves to augment the alternator. As larger, pad-driven alternators became available, the TC aircraft world readily embraced the notion of simply adding the second, smaller alternator in tandem with the main alternator but with no significant changes to original architecture (See Z12). The larger pad-driven machine reduced concerns for parasitic loads like battery contactors. It also simplified crafting plan-B requirements for load-shedding. The value of an E-bus goes down. This narrative is intended to encourage well considered decisions for 'enhancing' a Z-figure. We have an opportunity here on the List to advance the state of our art and science with tools the TC aircraft world has largely abandoned. In no way do I suggest that enhancements are not useful . . . to be sure, Z-figs have evolved considerably over 31 years of collective consideration by what must now include several thousand observers/ contributors. Let us continue to refine old or advance new ideas . . . but let's do it by the numbers and with diligent respect for lessons learned. Bob . . . ________________________________ Message 2 _____________________________________ Time: 12:10:09 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: List subscription problems? I've had some reports of subscribers to the List being 'dropped' for reasons unknown. In each case, the victim was able to renew their membership through the /subscribe page on matronics.com Has anyone else experienced this difficulty? Bob . . . ________________________________ Message 3 _____________________________________ Time: 01:19:49 PM PST US From: Christopher Cee Stone Subject: Re: AeroElectric-List: List subscription problems? Bob... Yes, was dropped and unable to log in to re-subscribe. Contacted Matt and the issue was resolved. -Chris Stone On Tue, Feb 26, 2019 at 12:14 PM Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > nuckolls.bob@aeroelectric.com> > > I've had some reports of subscribers to the > List being 'dropped' for reasons unknown. > > In each case, the victim was able to renew > their membership through the /subscribe page > on matronics.com > > Has anyone else experienced this difficulty? > > > Bob . . . > > ________________________________ Message 4 _____________________________________ Time: 07:17:12 PM PST US Subject: AeroElectric-List: Buy [5Pieces] Samsung Galaxy New S10/S10+ 128GB $3,495CAD From: "trptioip" Available to buy on our website www . esellibuy . com Read this topic online here: http://forums.matronics.com/viewtopic.php?p=487829#487829 ------------------------------------------------------------------------------------- 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.