---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 07/19/11: 11 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:24 AM - Load Analysis Spread Sheet (mike) 2. 01:23 AM - Re: Load Analysis Spread Sheet (B Tomm) 3. 03:27 AM - Re: Load Analysis Spread Sheet (James Kilford) 4. 06:20 AM - Re: TXDR & Nav/Com light sensors (racerjerry) 5. 08:43 AM - Re: multiple shield ground wires (jayb) 6. 09:13 AM - Re: Drawing Z-13/20 (Robert L. Nuckolls, III) 7. 09:16 AM - Re: Load Analysis Spread Sheet (Robert L. Nuckolls, III) 8. 09:19 AM - Re: Re: multiple shield ground wires (Robert L. Nuckolls, III) 9. 10:30 AM - Re: Load Analysis Spread Sheet (Vern Little) 10. 12:38 PM - Re: Load Analysis Spread Sheet (Bill Watson) 11. 04:19 PM - Re: Load Analysis Spread Sheet (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 12:24:45 AM PST US From: "mike" Subject: AeroElectric-List: Load Analysis Spread Sheet Kind of a beginner's question here. I am sure someone out there has a good example of a Load Analysis, or perhaps something in visual basic, accounting for varying power loads in their design? I am looking for a coherent graphic of an electrical architecture that might be modifiable towards the design I have in mind. Failing that does anyone have a laundry list of power consumptions of representative airframe equipment found in light aircraft I could use as a starting point? Just trying to save some re-invent the wheel time. Thanks in advance, ________________________________ Message 2 _____________________________________ Time: 01:23:23 AM PST US From: "B Tomm" Subject: RE: AeroElectric-List: Load Analysis Spread Sheet Check this one out courtesy of Vertical Power. http://www.verticalpower.com/docs/Device_Amps.pdf Bevan _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of mike Sent: Tuesday, July 19, 2011 12:21 AM Subject: AeroElectric-List: Load Analysis Spread Sheet Kind of a beginner's question here. I am sure someone out there has a good example of a Load Analysis, or perhaps something in visual basic, accounting for varying power loads in their design? I am looking for a coherent graphic of an electrical architecture that might be modifiable towards the design I have in mind. Failing that does anyone have a laundry list of power consumptions of representative airframe equipment found in light aircraft I could use as a starting point? Just trying to save some re-invent the wheel time. Thanks in advance, ________________________________ Message 3 _____________________________________ Time: 03:27:07 AM PST US Subject: Re: AeroElectric-List: Load Analysis Spread Sheet From: James Kilford Mike, I found a useful exercise was to create a spreadsheet with columns for various stages of flight (e.g. startup, taxi, climbout, cruise, descent, etc.) and rows for the various items of equipment. Some basic formulas will give you a precise understanding of the loads at different points, along with a theoretical maximum. You can further break this down so that the rows are grouped together in "busses", e.g. main bus, endurance bus, to then determine other answers, e.g. how long might your battery last if you're on your endurance bus without an alternator. I've a spreadsheet with all this on if you want it. HTH James On 19 July 2011 08:20, mike wrote: > ** > Kind of a beginner's question here. I am sure someone out there has a good > example of a Load Analysis, or perhaps something in visual basic, accounting > for varying power loads in their design? I am looking for a coherent graphic > of an electrical architecture that might be modifiable towards the design I > have in mind. Failing that does anyone have a laundry list of power > consumptions of representative airframe equipment found in light aircraft I > could use as a starting point? Just trying to save some re-invent the wheel > time. > > Thanks in advance, > > > * > > * > > ________________________________ Message 4 _____________________________________ Time: 06:20:44 AM PST US Subject: AeroElectric-List: Re: TXDR & Nav/Com light sensors From: "racerjerry" I had the same symptoms. A flashlight shined directly on the photocell restored everything to normal brightness. After many years, the photocell material apparently oxidizes and disappears with age. If you have a smattering of electronics knowledge and experience with a soldering iron, the photocell (V301) on the KT-76A is not too difficult to replace as it is located off the main board on a separate switch board assy. behind the front panel. GOOGLE part no. 134-05005-0002. Mine cost me about $15 + shipping in 2006. -------- Jerry King Read this topic online here: http://forums.matronics.com/viewtopic.php?p=347022#347022 ________________________________ Message 5 _____________________________________ Time: 08:43:14 AM PST US Subject: AeroElectric-List: Re: multiple shield ground wires From: "jayb" I contacted the vendor and they stated that the diagram that showed shield grounds on both ends was a typo. One end only. Glad I asked the question though as there's always more to learn! Cheers, Jay "Follow the instructions. Shields can be shield-only, attach one end; or shield+purposful conductor, attach both ends as prescribed." Read this topic online here: http://forums.matronics.com/viewtopic.php?p=347043#347043 ________________________________ Message 6 _____________________________________ Time: 09:13:41 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Drawing Z-13/20 At 10:39 PM 7/18/2011, you wrote: >Forget my question (if you haven=92t done so >already) regarding why Z-13/20 went away with >Revision 12 of AEC. I found my answer. I=92m >getting this Matronics Email-Serve thing figured >out (i.e. search ' Duh!). You must have the >patience of Job, being asked the same question over and over. It happens in every classroom semester after semester . . . > >That said, I did an analysis of Z-12, and it is >quite similar to Z-13/20 with a few notable >exceptions. I have a couple of questions and observations regarding Z-12. > >The field for both alternators is fed from the >main bus. If the Aux alternator field was fed >from the E-Bus, it would provide battery current >should the Battery Contactor Fail (however >unlikely), with no apparent downside to the >overall design, other than the E-Bus alternate >feed would need to be switched on. Am I reading >this right, or is there more to it? This brings up a more basic question. If the battery contactor fails -AND- you stall the alternator -AND- assuming it won't come up self-excited only -THEN- are you limited to what runs off the e-bus from energy contained in a well-maintained battery. I'm told that belt driven alternators running at 10 KRPM will, for the most part, come up self excited. > >What is the intended normal operating position >of the E-Bus Alternate Feed Switch? It would >seem that it could be operated in the =93On=94 >position (enabled to provide battery power >=93when=94 the battery contactor fails) or Off >position (requiring it to be turned on =93when=94 the contactor fails). The original idea was to close the e-bus alternate feed during pre-flight to test the path (an perhaps get clearance delivery and ATIS). Then leave it off for remainder of flight. > >The Z-12 design powers both the main and E-Bus >from both alternators. Does this assume the >pilot will shed load (if necessary) from the >main bus necessary to stay below the output of >the backup alternator in order to save the >battery, until those devices are required for approach and landing? Correct. Z-12 was included in the Z-figures not so much because it was recommended for new design. It's an example of how the SD-20 can be added to and existing Z-11 style system (typical of most TC aircraft). Z-12 is installed in hundreds of TC aircraft as a factory options or aftermarket kit. However, Z-12 is a perfectly practical way to integrate the SD-20 into a single battery, two alternator system whether by system upgrade or new construction. MUCH preferred over the abortive Z-13/20. If one is inclined to dual batteries, then Z-14 is a seamless way to get the two alternators wired up. > >Bob, I=92m sure you know that when we ask these >questions, it=92s because (hopefully) we are thinking, which is a good thing. Absolutely! > I=92m sure you=92re beyond taking > challenges/questioning of your designs > personally. I for one really appreciate you > taking the time to answer questions and being here to educate. A recipe for success built from the minimum numbers of simple-ideas defends itself. If a recipe has errors of fact in logic or performance, it needs to be fixed . . . The teacher's worst nightmare is to discover a long history of promoting a bad idea for lack of study or errors in perception. Propagandists don't concern themselves with such things. Bob . . . ________________________________ Message 7 _____________________________________ Time: 09:16:51 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Load Analysis Spread Sheet At 02:20 AM 7/19/2011, you wrote: >Kind of a beginner's question here. I am sure someone out there has >a good example of a Load Analysis, or perhaps something in visual >basic, accounting for varying power loads in their design? I am >looking for a coherent graphic of an electrical architecture that >might be modifiable towards the design I have in mind. Failing that >does anyone have a laundry list of power consumptions of >representative airframe equipment found in light aircraft I could >use as a starting point? Just trying to save some re-invent the wheel time. Check out the downloads at: http://www.aeroelectric.com/PPS/Load_Analysis/ If you're handy with Excel and really want a self-calculating spread sheet, there are a couple of examples. Others here on the List no doubt have others to share. If you're doing a study on a Beechjet, then a spread-sheet is the only way to go. I suspect that a simple pencil/paper/calculator apporach is the fastest path to understanging by filling our a form like http://www.aeroelectric.com/PPS/Load_Analysis/Blank_Form.pdf This is an adaptation of the forms we were using on TC aircraft 60 years ago. Bob . . . ________________________________ Message 8 _____________________________________ Time: 09:19:05 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: multiple shield ground wires At 10:39 AM 7/19/2011, you wrote: > >I contacted the vendor and they stated that the diagram that showed >shield grounds on both ends was a typo. One end only. Glad I asked >the question though as there's always more to learn! Any day you go to bed knowing something you did not know that morning is a GOOD day. Any day you can tap the sum of your knowledge and experience to make the life of somebody else easier, it's a GREAT day. Bob . . . ________________________________ Message 9 _____________________________________ Time: 10:30:28 AM PST US From: "Vern Little" Subject: Re: AeroElectric-List: Load Analysis Spread Sheet Check www.verticalpower.com for their load planning spreadsheets. -Vern From: Robert L. Nuckolls, III Sent: Tuesday, July 19, 2011 9:14 AM Subject: Re: AeroElectric-List: Load Analysis Spread Sheet At 02:20 AM 7/19/2011, you wrote: Kind of a beginner's question here. I am sure someone out there has a good example of a Load Analysis, or perhaps something in visual basic, accounting for varying power loads in their design? I am looking for a coherent graphic of an electrical architecture that might be modifiable towards the design I have in mind. Failing that does anyone have a laundry list of power consumptions of representative airframe equipment found in light aircraft I could use as a starting point? Just trying to save some re-invent the wheel time. Check out the downloads at: http://www.aeroelectric.com/PPS/Load_Analysis/ If you're handy with Excel and really want a self-calculating spread sheet, there are a couple of examples. Others here on the List no doubt have others to share. If you're doing a study on a Beechjet, then a spread-sheet is the only way to go. I suspect that a simple pencil/paper/calculator apporach is the fastest path to understanging by filling our a form like http://www.aeroelectric.com/PPS/Load_Analysis/Blank_Form.pdf This is an adaptation of the forms we were using on TC aircraft 60 years ago. Bob . . . ------------------------------------------------------------------------- ------- No virus found in this message. Checked by AVG - www.avg.com ________________________________ Message 10 ____________________________________ Time: 12:38:36 PM PST US From: Bill Watson Subject: Re: AeroElectric-List: Load Analysis Spread Sheet You are going thru the same process as all of us have. Look at everything you can find, steal as much as can and along the way you'll get you're head wrapped around it. My worksheet with load analysis is attached. I assume you are already familiar with Bob's Z-designs (a collection of well vetted electrical architectures for our machines). Starting (and staying) there is the way to avoid re-inventing any wheels. My version of Bob's Z-14 is also attached. On 7/19/2011 3:20 AM, mike wrote: > Kind of a beginner's question here. I am sure someone out there has a > good example of a Load Analysis, or perhaps something in visual basic, > accounting for varying power loads in their design? I am looking for a > coherent graphic of an electrical architecture that might be > modifiable towards the design I have in mind. Failing that does anyone > have a laundry list of power consumptions of representative airframe > equipment found in light aircraft I could use as a starting point? > Just trying to save some re-invent the wheel time. > Thanks in advance, > ________________________________ Message 11 ____________________________________ Time: 04:19:04 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Load Analysis Spread Sheet At 02:32 PM 7/19/2011, you wrote: >You are going thru the same process as all of us have. Look at >everything you can find, steal as much as can and along the way >you'll get you're head wrapped around it. Agreed. Many builders start with a strong urge to "keep everything running" in spite of inevitable failures of all kinds. By inevitable failure I mean no piece of hardware on your airplane has an infinite service life, nor are any components immune to the effects of error in craftsmanship or degraded performance due to misunderstanding or neglect. The short version of this idea is "Things Break". Suggest you review the article on Failure Modes Effects analysis at: http://www.aeroelectric.com/articles/Failure%20Modes%20Effects%20Analysis.pdf also chapter 17 in the 'Connection Then figure out what you plan to do personally to deal with the failure of any device or system in the airplane. It's easy to spend hours, pounds and dollars designing an electrical system that will keep every device in the airplane POWERED while ignoring the non-zero probability that that coveted system is not immune from FAILURE. I've mentioned many times here on this List that my personal approach to flying airplanes (always rental machines) is to be prepared to aviate and navigate and navigate to airport of intended destination in what I call "The J-3 Mode". Toward that end my flight bag has always included . . . http://aeroelectric.com/Pictures/Misc/Vacination_for_Dark_Panel_Syndrom.pdf My goals for having confidence to operate my airplane- of-the-day is predicated on the idea that at best I'll get there as long as the engine runs and the flight controls stay hooked up. At worst, I'll get an adventure on some airport I never before intended to visit. For anyone setting out to configure their electrical system, the first question is, "Can I operate this airplane in the vast majority of anticipated missions with the master switches OFF?" If the answer to that is "yes", then I'll suggest that your extra-ordinary needs for electrical energy are small to zero. If "no", then what's the practical solution to making sure the MINIMAL compliment of additional hardware is powered up for longer than you have fuel to keep the engine running? Start with solving that problem first. What is your MINIMALIST plan and skill set for comfortable termination of flight and figure the energy budget for delivering to that plan? If any of those equipment items are necessary for keeping the engine running they should be powered from a battery bus. In other words, if you've got smoke in the cockpit, you should be able to turn the master switch OFF and STILL continue to airport of intended destination. After conducting this exercise, then figure out how many more electro-whizzies you'd like to have running, not for necessity but for convenience. Any airplane can be successfully operated to a comfortable arrival with ZERO engine instrumentation . . . if you want to take the time to learn how to do it. An airplane can be successfully navigated with ZERO panel mounted nav-aids. Communication is a driving consideration only during the approach to landing phase and this can be done with a hand-held. After figuring out how you will achieve this level of confidence and competence with the manner in which you intend to use your airplane, then decide what your dollar, weight and volume budget is for adding more "stuff". This exercise goes to two important points. Only a tiny fraction of unhappy days in the cockpit have roots in electrical system failures. The vast majority of unhappy days in the cockpit have roots in poor piloting skills usually combined with poor decision making processes in dealing with what should be a no-big deal failure. If things didn't break on airplanes, FBO's would be out of business. Only YOU can make sure the majority if not all of your failures are a maintenance event as opposed to an emergency arising from lack of skill/planning. After this thought exercise you are now properly informed to carry out a load analysis that will drive architecture, weight, system complexity, and cost of ownership. The short review for all the above is, "Please disabuse yourself of the notion that backups to backups is any sort of replacement for understanding your machine, it's limitations and your own limitations. Tony Levier in a '60 model C-172 is a lot less likely to suffer a bad day in the cockpit than most of today's pilots buying a Malibu or A-36 with all the goodies. Some of my most enjoyable cross countries were conducted in the J-3 mode. Go down low, get out the maps, punch up a destination on the $100 hand held GPS and shut all the rest of that stuff off. If you can do it for fun, you can do it when conditions demand it. Bob . . . ------------------------------------------------------------------------------------- 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.