AeroElectric-List Digest Archive

Sun 03/19/06


Total Messages Posted: 17



Today's Message Index:
----------------------
 
     1. 01:20 AM - KR 87 (Richard Garforth)
     2. 05:45 AM - Backup fuel injection (was Z-19) (Ken)
     3. 05:47 AM - Re: Landing Light Circuit? (Eric M. Jones)
     4. 06:49 AM - Backup fuel injection (was Z-19) (BobsV35B@aol.com)
     5. 07:07 AM - Re: Backup fuel injection (was Z-19) (Ken)
     6. 08:09 AM - Re: redundant fuel delivery (was Z-19 questions) (Robert L. Nuckolls, III)
     7. 09:27 AM - Re: Headset and Mic Connections (Robert L. Nuckolls, III)
     8. 09:46 AM - Why is wire plated? ()
     9. 10:07 AM - Re: Why is wire plated? (Robert L. Nuckolls, III)
    10. 01:00 PM - Silicone wire ()
    11. 01:34 PM - Re: Re: Z-19 questions (John Burnaby)
    12. 05:57 PM - Any merit using a capacitor with ND alternator? ()
    13. 06:17 PM - NiCads (Alex Peterson)
    14. 06:50 PM - Re: NiCads (Vern Little)
    15. 07:18 PM - Re: NiCads (Brian Lloyd)
    16. 08:24 PM - Re: Any merit using a capacitor with ND alternator? (Robert L. Nuckolls, III)
    17. 10:03 PM - Re: Batt Charger/voltmeter/ammeter/temp (Speedy11@aol.com)
 
 
 


Message 1


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    Time: 01:20:23 AM PST US
    From: "Richard Garforth" <richard@hawk.flyer.co.uk>
    Subject: KR 87
    --> AeroElectric-List message posted by: "Richard Garforth" <richard@hawk.flyer.co.uk> Has anyone a copy of the KR 87 install manual that they could Email me please ? Richard RV10


    Message 2


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    Time: 05:45:34 AM PST US
    From: Ken <klehman@albedo.net>
    Subject: Backup fuel injection (was Z-19)
    --> AeroElectric-List message posted by: Ken <klehman@albedo.net> John Sure one injector will do it. That is how a carbuerator and countless throttle body injected cars run. While not absolutely necessary, with only one injector, it is usually positioned upstream of the throttle butterfly for good mixing which was difficult for me so I welded in four more ports for 4 used port injectors like newer cars do. The airflow is usually down into a throttle body injected engine which simplifies some things like fire risk. If you go to the megasquirt site http://www.megasquirt.info/v22manual/mtabcon.htm you will find hundreds of pages of info on the megasquirt computer and how it operates written for the many hundreds of neophytes that have built and installed it on just about every type of gas engine that exists. Better than most books on the subject. And several very active user groups to peruse or ask questions. I wouldn't bet my life on it but that little computer is totally adequate to control a backup fuel injection system if you are willing to invest the time to learn about it and save the cost of purchasing a second off the shelf system. I understand when someone says the primary system is orders of magnitude more reliable than the engine but that is not true for all the sensors, my wiring, or an overheated part that was not installed in the best place. Just before we take this off list (it is a bit off topic) I totally agree with Bob's post on fuel starvation. I installed a 2 gallon gravity fed header tank with a float switch in it to warn if it is ever not full. Ken John Burnaby wrote: >--> AeroElectric-List message posted by: "John Burnaby" <jonlaury@impulse.net> > >Ken, > >I'm intrigued. Could one just put a single injector squirting into the intake plenum? What takes the sensor signals and fires it? Just remember, you're talking to an electro-phobe. > >Thanks, >John > >


    Message 3


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    Time: 05:47:39 AM PST US
    Subject: Re: Landing Light Circuit?
    From: "Eric M. Jones" <emjones@charter.net>
    --> AeroElectric-List message posted by: "Eric M. Jones" <emjones@charter.net> Hi Ron, I can categorically state that an inductor of any use in a landing light circuit would weigh more than a watermellon. I think you are looking for an NTC thermistor to limit inrush current. These are little quarter-size parts that have a higher resistance when cold and a lower resistance when hot. Most thermistor makers have these. Digikey has p/n KC022L. When cold the part is 0.7 ohms and when hot it is 0.02 ohms (1/35th as resistive). This lowers the filament thermal shock considerably. It is important to realize that the part runs HOT. Make no attempt to cool it off. It wants to be mounted in still air, probably on the back of the lamp itself. The "keep-alive" lamp current technique uses power that could be better used elsewhere, but this is a personal choice. It is easy to make a soft-start switch in solid state too. -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones@charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=22617#22617


    Message 4


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    Time: 06:49:30 AM PST US
    From: BobsV35B@aol.com
    Subject: Backup fuel injection (was Z-19)
    --> AeroElectric-List message posted by: BobsV35B@aol.com Good Morning Ken and John, Some fifty plus years ago, I had a friend who was doing a lot of IFR flying in a Cessna 170. He had experienced a few problems with fuel feed. Plugged filters and such. His back up answer (long before the FAA came into existence and the CAA didn't bother GA as much as the FAA does now) was to place a "T" fitting at the outflow of the left main fuel tank. From there he ran a one-eighth inch copper line to the carburetor via a small needle valve mounted on the control panel. That line was fastened to a small fitting that he had inserted in the carburetor throat just down stream from the butterfly valve. He could stop the fuel from the normal system by turning off the fuel valve, open his auxiliary needle valve and control the power quite well by using the throttle valve to control airflow and the needle valve to control fuel. That setup bypassed almost all of the areas with which he had experienced difficulties. More than one way to skin a cat! Do Not Archive Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator Stearman N3977A Brookeridge Air Park LL22 Downers Grove, IL 60516 630 985-8503 In a message dated 3/19/2006 7:47:30 A.M. Central Standard Time, klehman@albedo.net writes: Sure one injector will do it. That is how a carburetor and countless throttle body injected cars run. While not absolutely necessary, with only one injector, it is usually positioned upstream of the throttle butterfly for good mixing which was difficult for me so I welded in four more ports for 4 used port injectors like newer cars do.


    Message 5


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    Time: 07:07:11 AM PST US
    From: Ken <klehman@albedo.net>
    Subject: Re: Backup fuel injection (was Z-19)
    --> AeroElectric-List message posted by: Ken <klehman@albedo.net> Yes I understand there were a number of such systems fitted. I've also heard that there were about as many problems caused by guys training (playing with it) as there were saves because of it. I guess some guys have even used a primer system with success. Since a manual system would have limited use on takeoff or on approach I decided to go with something a little more sophisticated. Ken BobsV35B@aol.com wrote: >--> AeroElectric-List message posted by: BobsV35B@aol.com > > > >Good Morning Ken and John, > >Some fifty plus years ago, I had a friend who was doing a lot of IFR flying >in a Cessna 170. > >He had experienced a few problems with fuel feed. Plugged filters and such. > > >His back up answer (long before the FAA came into existence and the CAA >didn't bother GA as much as the FAA does now) was to place a "T" fitting at the >outflow of the left main fuel tank. From there he ran a one-eighth inch >copper line to the carburetor via a small needle valve mounted on the control >panel. That line was fastened to a small fitting that he had inserted in the >carburetor throat just down stream from the butterfly valve. He could stop the >fuel from the normal system by turning off the fuel valve, open his auxiliary >needle valve and control the power quite well by using the throttle valve to >control airflow and the needle valve to control fuel. That setup bypassed >almost all of the areas with which he had experienced difficulties. > >More than one way to skin a cat! > >Do Not Archive > >Happy Skies, > >Old Bob >AKA >Bob Siegfried >Ancient Aviator >Stearman N3977A >Brookeridge Air Park LL22 >Downers Grove, IL 60516 >630 985-8503 > >


    Message 6


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    Time: 08:09:39 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: redundant fuel delivery (was Z-19 questions)
    --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net> At 06:23 PM 3/18/2006 -0500, you wrote: >--> AeroElectric-List message posted by: Ken <klehman@albedo.net> > >John > >The advice to not make a primary system less reliable by adding backups >that could compromise it is good advice. However if you want a second >system, an independant second system can certainly be installed that >does not have any common failure points or share items with the primary >system. Ideally neither system should know that the other exists. > >For example a backup efi might be a homemade megasquirt unit that shares >no sensors, wiring, injectors, etc. with the primary system. The >throttle sensor can be eliminated since airplane throttles are opened >slowly. The engine temperature sensor could be eliminated because the >engine will already be warm if the backup is needed. So a minimum system >needs a crank or cam sensor for rpm, a MAP sensor which is onboard the >$150. ish megasquirt, an inlet air temp sensor, one or more additional >injectors, an independant power source and a separate power switch. I'm >sure you already have a second fuel pump. A lot of reliability concerns >go away with the ability to just select another system. Exactly! Here's a post I made some years ago on that same topic suggesting an even simpler way to craft independent fuel delivery systems to on engine using stock hardware, no modifications to the engine and a simple, easy to implement procedure: From: "Robert L. Nuckolls, III" <nuckolls@aeroelectric.com> Subject: AeroElectric-List: Re: Fuel system failure . . . Sender: owner-aeroelectric-list-server@matronics.com --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckolls@aeroelectric.com> > >in regards to the fuel primer , what do you mean by primary system failure? >is this where you would be using a fuel flow meter with the vane paddles in >it ? they do warn to have a bypass in a system like this. i have used >two different types of electric primers that i put together , worked great >and were cheap. if you want i could tell you how i did it .........marty Some years ago(I believe I may have written about the idea in my first issue of the AeroElectric Connection) I suggested that builders consider a backup fuel delivery system. I opined that it was pretty easy to do . . . in fact, lots of certified airplanes are already fitted with a rudimentary backup system. DataPoint 1: I've read dozens of hangar flying stories over the years where a pilot suffered a variety of normal fuel delivery system failures (broken throttle linkage, stuck float in carb, plugged fuel lines, etc) and managed to nurse his airplane to a comfortable landing by stroking the primer pump. DataPoint 2: I connected these stories with a system I observed on the Beech Skipper (BE-77) in which I took my primary training. To prime the engine, one pressed in on the key while cranking. This closes an extra set of contacts in the key switch opening a solenoid valve that routes fuel from the downstream side of the boost pump to the primer lines. This made sure that the cranking motor was turning as raw fuel was fed to the engine. This improves vaporization efficiency because the engine is ingesting air while priming fuel is flowing. DataPoint 3: The so called fuel injected engines found on airplanes is very rudimentary when compared with modern EFI systems on automobiles but is technically elegant with respect to complexity. They simply deliver a calibrated pressure flow of fuel to a nozzle located just outside the intake valve of each cylinder. DataPoint 4: I've noted that some engines don't prime all cylinders, to make the backup delivery system work, you'd want to have fuel delivered to every cylinder. Other primers dump fuel into the carburetor which is fine too (More modern EFI engines might have a single nozzle dump fuel into the airflow just outside the throttle plate). Proposal: Borrowing from the electrically controlled primer system found on the BE-77 and perhaps other airplanes, how about putting a valve in the primer line that allows calibration of primer fuel flow to some rate commensurate with 60-70% power. A needle valve would work. Arrange to supply power to the boost pump and open the solenoid valve by the proper placement of switches in the cockpit. If one wanted to take redundancy to a logical limit, I'd put a separate finger strainer in a tank and supply the primer system with it's own electric pump. Now, should one find himself airborne with no way to get fuel to the engine through the normal delivery path, you would shut off the normal delivery system (valves closed, pump off, mixture to idle cutoff) and flip the primer switch on. The throttle then becomes a mixture control. Adjust throttle for best running engine. See: http://www.aeroelectric.com/Pictures/Schematics/NoValve.gif The reasoning here is that a simple enhancement to a stock primer system would provide an on-purpose backup to the normal fuel delivery system. Several years after I first proposed this system, a LongEz driver e-mailed me to say that his airplane suffered a frozen fuel selector valve and the handle broke off with the valve in a position that wouldn't allow delivery of useful fuel. The calibrated primer backup system did the job and he continued flight for over 30 minutes to an uneventful landing at an airport. Bob . . . -------------------------------------------------- ( "Imagination is more important than knowledge. ) ( It is a miracle that curiosity survives formal ) ( education" ) ( Albert Einstein ) --------------------------------------------------


    Message 7


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    Time: 09:27:40 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: Headset and Mic Connections
    --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net> At 01:19 PM 3/18/2006 -0500, you wrote: >--> AeroElectric-List message posted by: SMITHBKN@aol.com > >I ordered some headset and mic jacks from B&C Specialty. Are the >connections to these supposed to be soldered? If so, is there a standard >practice used >to attach the wire to the solder tabs on the jacks? The solder tabs have a >small diameter hole in them. See: http://aeroelectric.com/articles/Jack_Tab_Soldering/Jack_Tab_Soldering.html Bob . . . < What is so wonderful about scientific truth...is that > < the authority which determines whether there can be > < debate or not does not reside in some fraternity of > < scientists; nor is it divine. The authority rests > < with experiment. > < --Lawrence M. Krauss >


    Message 8


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    Time: 09:46:44 AM PST US
    Subject: Why is wire plated?
    From: <rparigor@SUFFOLK.LIB.NY.US>
    --> AeroElectric-List message posted by: <rparigor@suffolk.lib.ny.us> Sorry if this is a second post, first gave came back with a wierd error. Why is wire common found on aerocraft plated? What are advantages/disadvantages? What material is the plating? I want to use a short length of #12 with silicone insulation common to model electrics in the cockpit for it's ability to carry amps and remain very flexable (a gazillion strands of copper no plating). Thx. Ron Parigoris


    Message 9


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    Time: 10:07:47 AM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net>
    Subject: Re: Why is wire plated?
    --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net> At 05:44 PM 3/19/2006 +0000, you wrote: >--> AeroElectric-List message posted by: <rparigor@suffolk.lib.ny.us> > >Sorry if this is a second post, first gave came back with a wierd error. > >Why is wire common found on aerocraft plated? > >What are advantages/disadvantages? > >What material is the plating? > >I want to use a short length of #12 with silicone insulation common to >model electrics in the cockpit for it's ability to carry amps and remain >very flexable (a gazillion strands of copper no plating). Primary reason is to maintain conditions conducive to joining the wire. Bare copper will corrode and make soldering difficult. Corrosion also introduces contaminants into a crimped joint where clean, gas-tight joining is a goal. If you use new, un-plated wire and it's nice and bright before soldering or crimping, the material will be just fine for your project. Similarly, welding cable with super flexibility and low cost is attractive for many fat wires in an airplane. This wire is also fabricated from bare copper that's entirely suited to the task if bright and clean at time of assembly. I'm not familiar with "model electrics". I'm also curious as to popular use of silicone insulation. If I were to go on a shopping trip for silicone insulated wire, I'm not sure I could find any in Wichita beyond that which is offered on spark plug wires. It's not an insulation we commonly see on spools of wire intended for point to point interconnections. Can you enlighten us further? Bob . . . < What is so wonderful about scientific truth...is that > < the authority which determines whether there can be > < debate or not does not reside in some fraternity of > < scientists; nor is it divine. The authority rests > < with experiment. > < --Lawrence M. Krauss >


    Message 10


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    Time: 01:00:15 PM PST US
    Subject: Silicone wire
    From: <rparigor@SUFFOLK.LIB.NY.US>
    --> AeroElectric-List message posted by: <rparigor@suffolk.lib.ny.us> Hello Bob "I'm not familiar with "model electrics". I'm also curious as to popular use of silicone insulation" Model Electric Airplanes are getting much popular (as well as Helis and Boats), especial with new battery technology. Charging and switching about of battery packs, causes much flexing demands. Weight is critical, and the gazillion strands helps out not only on flexibility, but minimal weight for ability to carry amps. On models you often cheat on size of wire to save weight, and that can heat things up. Silicone insulation is very flexible and pretty good at high temperatures. In the quantities I buy, it is not cheap. Astroflight, Hobby Lobby and many others sell it. One of my favorite connectors, Sermos or Anderson Powerpole Modular connectors work awful well with Model Electrics. The 15 amp, 30 amp and 45 amp size is the same size, just the pins are different. I would much rather parallel 2 connectors than rely on 1. If things are perfect you can use a 30 amp for 30 amps. That said I do find from time to time signs of high resistance joints. Using 2 parallel 15s, never had a problem. They are going to be used in numerous locations on my Europa. Check out: http://www.yourzagi.com/wagmax.htm Go to fourth picture down, it shows parallel silicone wire and connectors. You can position the modular connectors so they are keyed so can not make a mistake. Can easily stack a dozen or more in a row or cube. www.mcmaster sells them. 2 parallel work great for Cessna landing lights in cowl, easy removal and install, even when real cold out. I will use them for connectors for allowing electron to my wings, which will be removed a fair amount. Off topic, but in that same picture #4, you will see black size E Dacron thread holding on my 3/4HP motor! This technique is unbelievable. Use a little JB Weld fast cure to get position you want, then use thin CA (Crazy type glue like Zap)to hold thread in place. A quick slice and tap and motor is off. Way off subject, buy some keen edge razor blades from McMaster Carr, they are black and super sharp. Break em with pliers for small on the spot scalpel. Same photo you can see the 2 Carbon Fiber rods, they are green. I go to an indoor Archery range, and garbage pick CF arrows that hit the cement wall, or the knocks get "Knocked" forward a few inches. Since most of these are unidirectional wrapped, they are not great in some directions as far as strength. I internal custom sleeve where more strength is desired, and then wrap the exterior with Spectra Fishing line and thin CA. If you have not played with this stuff, do so. Strong like steel, glues easily with thin CA, not good for high temperatures. Another appeal for holding batteries, is the spectra is not a good conductor. CF conducts better than you care for in many electrical instances. Spectra is pretty abrasion resistant. Anyway CF and Spectra wrap, and Size E Dacron are all making its way into Europa. Also McMaster check out Kevlar and Nomex thread. For much of my wires, and fuel lines instead of traditional nylon ty wraps on stand offs, I took a piece of Balsa Wood square 2 inches by 1 inch and laid up 1 ply BID. Then I sewed with Kevlar thread using a Zig Zag stitch Velcro to the 2 x 1. Then wrapped with thin .020 safety wire, and laid up 1 layer BID on bottom. Now just need to Redux this anywhere you need a hold-down. On my fuel lines going through the tunnel I put a piece of Velcro on the lines themselves. Ron Parigoris


    Message 11


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    Time: 01:34:17 PM PST US
    From: "John Burnaby" <jonlaury@impulse.net>
    Subject: Re: Z-19 questions
    --> AeroElectric-List message posted by: "John Burnaby" <jonlaury@impulse.net> How I love this list. Thanks Bob, for once again clarifying the options and saving me time and money. John do not archive


    Message 12


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    Time: 05:57:55 PM PST US
    Subject: Any merit using a capacitor with ND alternator?
    From: <rparigor@SUFFOLK.LIB.NY.US>
    --> AeroElectric-List message posted by: <rparigor@suffolk.lib.ny.us> Is there any merit using a 22,000mF capacitor with a SD-20s alternator and a LR3C linear regulator as far as: Keeping things stable if battery were to go off line (my main reason for asking this question)? Perhaps reducing some sort of noise? Other? ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Rotax 914 internal generator and Ducati regulator/rectifier as per the install manual have you install a 22,000mF capacitor. I think idea is not only for noise control, but if the battery goes off line it will keep things stable. Rotax has an optional 40 amp ND alternator with internal regulator. I suspect it is a switching regulator. Anyway as per the install manual have you install a 22,000mF capacitor. Thx. Ron Parigoris


    Message 13


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    Time: 06:17:49 PM PST US
    From: "Alex Peterson" <alexpeterson@earthlink.net>
    Subject: NiCads
    --> AeroElectric-List message posted by: "Alex Peterson" <alexpeterson@earthlink.net> Years ago, I knew an electrical engineer who claimed he could rejuvenate NiCad batteries by charging a capacitor and zapping it across the battery. I watched him do this, and saw what I recall were positive results. He claimed it reduced the internal resistance, so they would hold a charge better. Is there anything to this? Alex Peterson RV6-A N66AP 729 hours Maple Grove, MN


    Message 14


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    Time: 06:50:07 PM PST US
    From: Vern Little <rv-9a-online@telus.net>
    Subject: Re: NiCads
    --> AeroElectric-List message posted by: Vern Little <rv-9a-online@telus.net> I've done it a lot. I used it to blow out internal shorts in battery packs. I'd take a big computer-grade low esr electrolytic, charge it with a power supply then connect it to the batter pack. The large current would blow out any internal shorts. This works a few times, but is not a permanent fix for NiCd problems. Also, the charge rate of NiCd batteries is proportional to the discharge rate... so the trick is to discharge them quickly, then charge them quickly using special chargers (battery charger/conditioners). Also, it's better to pulse charge the NiCd batteries, rather than using a smooth DC charging source. You may want to Google it, because there is a lot of info available. Vern Little Alex Peterson wrote: > --> AeroElectric-List message posted by: "Alex Peterson" <alexpeterson@earthlink.net> > > Years ago, I knew an electrical engineer who claimed he could rejuvenate > NiCad batteries by charging a capacitor and zapping it across the battery. > I watched him do this, and saw what I recall were positive results. He > claimed it reduced the internal resistance, so they would hold a charge > better. Is there anything to this? > > > Alex Peterson > RV6-A N66AP 729 hours > Maple Grove, MN > > > > > > > > > > > > > > > > >


    Message 15


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    Time: 07:18:47 PM PST US
    From: Brian Lloyd <brian-yak@lloyd.com>
    Subject: Re: NiCads
    --> AeroElectric-List message posted by: Brian Lloyd <brian-yak@lloyd.com> Alex Peterson wrote: > --> AeroElectric-List message posted by: "Alex Peterson" <alexpeterson@earthlink.net> > > Years ago, I knew an electrical engineer who claimed he could rejuvenate > NiCad batteries by charging a capacitor and zapping it across the battery. > I watched him do this, and saw what I recall were positive results. He > claimed it reduced the internal resistance, so they would hold a charge > better. Is there anything to this? There is something to this but it is not because it reduced the internal resistance. Seems that NiCds have a tendency for the sodium hydroxide electrolyte to form conductive crystals if the battery is left discharged. The crystals grow through the separator and cause a short between the plates (electrodes inside the battery). When that happens you can't charge the NiCd. What the capacitor does is provide a huge momentary current that destroys these crystals without overheating the battery. Once the shorts are blown clear, the battery will then take a charge. The only caveat is, when this happens it usually means that the battery is approaching the end of its life. The crystal is not completely destroyed but the short is removed. The crystal is likely to grow back and short the cell again. Still, it is a useful technique if you need to get a couple more cycles from your NiCds. -- Brian Lloyd 361 Catterline Way brian-yak at lloyd dot com Folsom, CA 95630 +1.916.367.2131 (voice) +1.270.912.0788 (fax) I fly because it releases my mind from the tyranny of petty things . . . - Antoine de Saint-Exupery


    Message 16


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    Time: 08:24:50 PM PST US
    From: "Robert L. Nuckolls, III" <nuckollsr@cox.net> alternator?
    Subject: Re: Any merit using a capacitor with ND alternator?
    --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" <nuckollsr@cox.net> alternator? At 01:50 AM 3/20/2006 +0000, you wrote: >--> AeroElectric-List message posted by: <rparigor@suffolk.lib.ny.us> > >Is there any merit using a 22,000mF capacitor with a SD-20s alternator and >a LR3C linear regulator as far as: >Keeping things stable if battery were to go off line (my main reason for >asking this question)? >Perhaps reducing some sort of noise? >Other? >~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ >Rotax 914 internal generator and Ducati regulator/rectifier as per the >install manual have you install a 22,000mF capacitor. I think idea is not >only for noise control, but if the battery goes off line it will keep >things stable. > >Rotax has an optional 40 amp ND alternator with internal regulator. I >suspect it is a switching regulator. Anyway as per the install manual have >you install a 22,000mF capacitor. Nope, if there was some benefit to be realized, we would have included it in the recommended installation drawings. That isn't to say that adding a capacitor won't reduce some noise characteristics. It's just that the noise from a 3-phase, wound field alternator is a known quantity that falls below acceptable limits expected on a DC alternator/battery system. See: http://www.aeroelectric.com/Pictures/Curves/MSTD704_28V_Noise.jpg These noise values are for a 28v system, half them for 14v. Everyone who is a savvy supplier to the industry EXPECTS and designs their products to live in this environment. Should you encounter a device not designed to live in the real world, it's usually easier to filter off the offending noise at input to the victim as opposed to attacking it at the source. Bob . . .


    Message 17


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    Time: 10:03:11 PM PST US
    From: Speedy11@aol.com
    Subject: Re: Batt Charger/voltmeter/ammeter/temp
    --> AeroElectric-List message posted by: Speedy11@aol.com Sorry I asked. I'll know better next time. Stan Sutterfield Do Not Archive Anyone have experience with this product? http://www.customdynamics.com/kisan-battery-charger.htm Is it any good?




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