---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Wed 01/24/24: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:27 AM - Re: Re: Z101B and battery in the rear wiring question (Werner Schneider) 2. 02:24 AM - Re: Z101B and battery in the rear wiring question (user9253) 3. 03:09 AM - Re: Re: Z101B and battery in the rear wiring question (Werner Schneider) 4. 04:06 AM - Re: Re: Z101B and battery in the rear wiring question (Werner Schneider) 5. 07:49 AM - Re: Z101B and battery in the rear wiring question (user9253) 6. 10:08 AM - Re: OVM-14 MkIII development (update) (Robert L. Nuckolls, III) 7. 10:08 AM - 'Funky' fuses and other interesting adventures (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 12:27:26 AM PST US Subject: Re: AeroElectric-List: Re: Z101B and battery in the rear wiring question From: Werner Schneider Thanks a lot Joe for your thoughts, if I connect the wire 1 at the starter contactor I would defy the idea of Z101, that the aux alternator can feed the essential bus without switching on the main contactor, so I rather would like to keep that as in the original architecture. The main alternator feed can be protected close to the starter contactor here, as it would need a huge fuse when being close to the main contactor (starter current). Unfortunately due to CG reasons I need to have the battery at the rear end I agree would be easier/more logical on the FW..... Cheers Werner On 24.01.2024 03:43, user9253 wrote: > > In case of an immanent forced landing or smoke in the cockpit, the pilot should > have the ability to shut off all electrical power as close to the source as possible. > To comply with that rule, the battery contactor and other relays should be located > near the battery. The starter contactor may be located at the firewall. > Z-101 was not intended for a rear mounted battery. And so I recommend connecting > the 10AWG aux alternator wire that you have labeled "1" to the starter contactor > just like the main alternator is with a fuselink. If you do that, then > there will not be always-hot wires running from the back to the front. > Alternators do NOT need to be protected against producing too much current. > Alternators can not produce much more than they are rated for. Protection for > alternator feeders should be located closer to the battery end, not at the alternator end. > > -------- > Joe Gores > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=513130#513130 > > ________________________________ Message 2 _____________________________________ Time: 02:24:10 AM PST US Subject: AeroElectric-List: Re: Z101B and battery in the rear wiring question From: "user9253" > if I connect the wire 1 at the starter contactor I would defy the idea > of Z101, that the aux alternator can feed the essential bus without > switching on the main contactor That is not correct. If your wire #1 is connected to the starter contactor, then the path is from Aux Alt to starter contactor to downstream side of battery contactor to pink bridge rectifier diode to normal feed to brownout/AUX Bus. You might have to reduce the main bus electrical load depending on the capability of the aux alternator. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=513132#513132 ________________________________ Message 3 _____________________________________ Time: 03:09:25 AM PST US Subject: Re: AeroElectric-List: Re: Z101B and battery in the rear wiring question From: Werner Schneider Hi Joe, how could I doubt your advice :( (I just overlooked that path via the diode) That is very elegant, as the Aux would source the whole system the wire run would be short (and common to both alternators) (you would not use the blade fuses instead a fusible link in front of the starter contactor point?) So there would be a bit a different logic: - standard feed by main alternator to both buses - in case main fails Aux takes over all buses (independent if battery contactor is on or off (but should remain on to have stabilizing battery in system), reducing load on main bus could keep load in limits of Aux alternator - in case both fail the alt feed switch would connect the essential/engine bus directly to the bat. Simple and elegant, I bow my head to you for that solution, thank you!! Werner On 24.01.2024 11:23, user9253 wrote: > > >> if I connect the wire 1 at the starter contactor I would defy the idea >> of Z101, that the aux alternator can feed the essential bus without >> switching on the main contactor > That is not correct. If your wire #1 is connected to the starter contactor, then > the path is from Aux Alt to starter contactor to downstream side of battery > contactor to pink bridge rectifier diode to normal feed to brownout/AUX Bus. > You might have to reduce the main bus electrical load depending > on the capability of the aux alternator. > > -------- > Joe Gores > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=513132#513132 > > ________________________________ Message 4 _____________________________________ Time: 04:06:51 AM PST US Subject: Re: AeroElectric-List: Re: Z101B and battery in the rear wiring question From: Werner Schneider So it would look something like this, only long wire would be #3 but could be disconnected via the relay high concentration on starter contactor now of # of connection On 24.01.2024 11:23, user9253 wrote: > > >> if I connect the wire 1 at the starter contactor I would defy the idea >> of Z101, that the aux alternator can feed the essential bus without >> switching on the main contactor > That is not correct. If your wire #1 is connected to the starter contac tor, then > the path is from Aux Alt to starter contactor to downstream side of batt ery > contactor to pink bridge rectifier diode to normal feed to brownout/AUX Bus. > You might have to reduce the main bus electrical load depending > on the capability of the aux alternator. > > -------- > Joe Gores > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=513132#513132 > > ======================== ============ ======================== ============ ======================== ============ ======================== ============ ======================== ============ > > ________________________________ Message 5 _____________________________________ Time: 07:49:56 AM PST US Subject: AeroElectric-List: Re: Z101B and battery in the rear wiring question From: "user9253" Werner, some well respected people like Bob N. and Charlie E. prefer to use fusible links instead of ANL fuses. Fusible links have advantages: light weight and no exposed terminals that could short out and less money. It is a matter of personal choice. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=513137#513137 ________________________________ Message 6 _____________________________________ Time: 10:08:16 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Re: OVM-14 MkIII development (update) Haven't been ignoring you guys . . . fun projects got kinda diluted with holiday festivities and frivolities along with a few home maintenance items that could not wait . . . But in the mean time: I've been fiddling with the etched circuit for the prototype OVM-14 upgrade . . . due to the very compact ecb layout I was interested in exploring solder reflow assembly processes using joint-by-joint application of solder paste. The experiments were frustrating. The consistency and makeup of the solder 'paste' is critical. Samples I had on hand proved problematic in that they were reluctant to 'stick' to the pad until the component was placed. Seems this stuff has a shelf life too. Finally did conquer the process but while working with these cute little boards, it occurred to me that it was a bit late in my career life cycle to be spooling up in new manufacturing processes and inventorying new products! To my way of thinking, the optimized assembly configuration would lend itself to offering bare boards or even kits in addition to limited sales of completed assemblies while striving for compact assembly. Thought I give this a try: The attached figure is a snapshot of the present configuration OVM-14 ECB. It's not terribly larger than the legacy CBOVMs. I've not used this assembly technique in more years than I can recall . . . first observed it in the fabrication of my first solid state pocket radio. A Regency TR1 that cost me a pretty penny in newspaper route earnings about 1958! Note the resistors stand on end soldered into pads with very close spacing. This offers a tighter layout opportunity with another benefit: The upper end of each resistor can be oriented such that it attaches to an interesting 'test node' on the board. An oscilloscope or voltmeter probe can be clipped to the lead wire for performance evaluation and/or troubleshooting. What, you may ask, is that 'thing' hanging off the end of the board? My short path to low cost prototype boards is predicated on a fixed 3.8 x 2.5 inch coupon. Hmmm . . . what to do with that opportunity for a 'free' ecb? How about exploring a recently noticed LED product that caters to night time drone pilots? Red or green LEDs with built in flashers. A bit slower than I'd like but certainly bright enough. I've added a little 'parasite' board to the layout to proof an idea for a precision low volts warning annunciator with a very low parts count. I'll publish drawings for the ECB shortly with the notion of exploiting any willing talents for proofing the layout. I've got an order into Digikey for thru-hole parts to assemble the prototypes which should go VERY quickly. This may not be the optimal route but I think it's better than the rabbit hole I dove into the first time. Let's see what shakes out. Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ In the interest of creative evolution of the-best-we-know-how-to-do based on physics and good practice. ________________________________ Message 7 _____________________________________ Time: 10:08:36 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: 'Funky' fuses and other interesting adventures Shortly before the holidays we had a brief thread concerning the relative merits of utilizing automotive fuses of unknown source and equally unknown qualifications. We harkened to the admonitions from representatives of Busssman, Littlefuse, etc. etc: "NO . . . you can't have that . . . you'll shoot your eye out!" Oops . . . wrong movie . . . "Those fuses do not come with the assurances of performance control and reliability offered by our products . . . you're gonna set your wires on fire!" Okay, as we've discussed many times on this forum over the years, the science of good design requires a working knowledge in properties of materials, management of energy and refinement of process. Doesn't matter if you're baking cheese souffle, building a house . . . or wiring an airplane. There's another bit of wisdom handed down to us from history: "I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind." ---- Lord Kelvin ---- To be sure, a great deal of what is pushed down on us these days is considerably lacking in numbers! Okay, let's consider how we can 'go get the numbers'. I've acquired a new tool for the mess-making shop. Toward the goal of being able to test and quantify performance on various components, an accurately calibrated electronic load-bank is of considerable value. This critter will sink up to 250 watts with max voltage of 100; max current of 50A. It features a pulse generator that allows the load to be modulated with excursions in both magnitude, frequency and duration. I've not enjoyed this capability since the last regulator I did for Beech about a bazillion years ago. It also has a scaled current sample port that will drive my oscilloscope. This instrument will be invaluable for evaluating a box of 'funky' fuses. I will suggest there are two experiments to be designed and conducted. (1) compare interruption characteristics of the funky fuses with some name brand devices -and- their data sheets. (2) craft an experiment that attempts to set a wire on fire . . . or at least cause a level of destruction that generates expensive repairs if not risks to comfortable completions of flight. Things are moving ahead with the test stand. How would we set up the experiment for demise of an 'inadequately' protected wire? Keep in mind that my prodigal environmental chamber has returned from a 20-year 'sabbatical' so our experiment can include elevated environmental temperature effects. Bob . . . //// (o o) ===========o00o=(_)=o00o======== < Go ahead, make my day . . . > < show me where I'm wrong. > ================================ In the interest of creative evolution of the-best-we-know-how-to-do based on physics and good practice. ------------------------------------------------------------------------------------- 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.