---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 09/28/08: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 12:16 AM - Re: A Tale of Two Batteries (Ed Holyoke) 2. 09:29 AM - Re: A Tale of Two Batteries (Robert L. Nuckolls, III) 3. 10:14 AM - Regulated voltage to high (Bob Verwey) 4. 12:08 PM - Re: A Tale of Two Batteries (Ed Holyoke) 5. 06:21 PM - Transponder and Radio position (Carlos Trigo) 6. 06:25 PM - Re: A Tale of Two Batteries (Robert L. Nuckolls, III) 7. 06:37 PM - Re: Transponder and Radio position (Sam Hoskins) 8. 09:05 PM - Re: capacitance probes (James Robinson) ________________________________ Message 1 _____________________________________ Time: 12:16:41 AM PST US From: Ed Holyoke Subject: Re: AeroElectric-List: A Tale of Two Batteries Howdy Bob, I'd be interested to find out what the protocols are for salvaging damaged batteries. Got nothing to lose, after all. I guess I'll poke around the Concorde site and see if I can dig anything up. I was going to build the test rig you wrote about long ago with the electric clock and the zener diode cutout circuit, but I never go around to it and, when I read about the CBA, I thought "That's what I really want". It is a much more sophisticated and capable tool. On another note, is the VDC battery minder - aviation adjusted that much better than the standard 12248 charger which can be had about $65 cheaper? What is the AA, just a tenth of an amp or so lower setting, or is it magic? Pax, Ed Holyoke > > As a side note, there are tests conducted on deliberately > abused batteries to demonstrate an ability to recover from > that abuse. I don't recall the specifics but they involved > taking a battery down to 0 capacity for a long period of > time and then cycling it through a series of charge and > discharge protocols while measuring the useful capacity > of the battery during each discharge. All of Concorde's > products are qualified to these requirements as are > Hawker's aircraft products. > > I've seen quantities of $high$ batteries sitting in Concorde's > warranty return pile where the techs reported successful > recovery of a substantial number of the returns. Some had > be discharged and out of service for months. I don't > recall the figures but somewhere around 1/3 were > recoverable to 80% or better capacity. > > This data suggests that many batteries are returned > for warranty not because they are defective. They > came back because the user (or his mechanic) didn't understand > how ingredients that go into the recipe for success > in aircraft power generation and storage systems > worked together. > > Batteries are secretive buggers. There are no dials, > no diagnostic ports, and a host of vulnerabilities > to optimized performance. Without tools of investigation > and maintenance, the user is playing the odds that > don't get any better by being ignorant. > > As you've discovered, it takes $time$ and $investment$ > to achieve your level of understanding. Most airplane > owners are not compelled to make such expenditures. That's > why I've often recommend that folks buy the least > expensive battery and replace it every year. This > protocol may well provide a superior system reliability > with a minimum cost of ownership. > > It's that CBA a slick tool? By the way, you can use > it also as a data acquisition system. If you'd like to > measure and plot a voltage over a long period of time, > set it up to "test" a battery with 0.01A of discharge > rate. If this level of load is so small that it doesn't > adversely affect your system under investigation, then > the software will dutifully march off and gather the > data for you and put it out in nice plots. I own > two of those critters. > > Bob . . . > > ________________________________ Message 2 _____________________________________ Time: 09:29:48 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: A Tale of Two Batteries At 12:15 AM 9/28/2008 -0700, you wrote: > >Howdy Bob, > >I'd be interested to find out what the protocols are for salvaging damaged >batteries. Got nothing to lose, after all. I guess I'll poke around the >Concorde site and see if I can dig anything up. I may have the process document someplace. If I can't find it, I can get it from Concorde. It's not "magic". It doesn't use any form of incantation like de-sulfation pulsers, etc. As I recall it starts with a controlled over-charge that pushes the terminal voltage pretty high until internal resistance to come down. I think I recall Skip talking about 20 volts or more on a 12v battery. After the battery demonstrates a willingness to draw current in a more typical recharge mode, the battery is subjected to a series of constant current, charge- discharge cycles with each discharge cycle being quantified for energy delivered. Early in the process, successive discharges grow stronger. After the ability to store energy flattens out, the battery may be either deemed serviceable or ready for re-cycling. This process won't "refurbish" a worn out battery but it may "wake up" a mis-treated battery. >I was going to build the test rig you wrote about long ago with the >electric clock and the zener diode cutout circuit, but I never go around >to it and, when I read about the CBA, I thought "That's what I really >want". It is a much more sophisticated and capable tool. Yup, in this business tools is what it's all about. No matter how much you understand, you're not going to drive that nail without at least a hammer. Without the hammer, you're skill-set remains un-quantified and un-demonstrated. >On another note, is the VDC battery minder - aviation adjusted that much >better than the standard 12248 charger which can be had about $65 cheaper? ALL of the smart chargers that do constant current, voltage limited charging, top-off followed by a maintenance mode are about 1000 light years ahead of any "trickle- charger" of yesteryear. Like this: http://www.aeroelectric.com/Pictures/Curves/Ideal_Recharge_Protocol.jpg Now, here's the measured performance on a variety of "smart chargers" . . . http://www.aeroelectric.com/Pictures/Curves/Battery_Minder_Recharge.pdf http://www.aeroelectric.com/Pictures/Curves/Battery_Tender_Recharge.pdf http://aeroelectric.com/Pictures/Battery_Chargers/Schumacher_Chargers/SC2500-50AH.jpg http://www.aeroelectric.com/Pictures/Curves/HF93258_1.jpg http://www.aeroelectric.com/Pictures/Curves/schumacher_2.jpg http://www.aeroelectric.com/Pictures/Curves/schumacher_3.jpg http://www.aeroelectric.com/Pictures/Curves/schumacher_5.jpg None of these charge/maintenance protocols are identical to another one. Some don't exactly capture the "Idealized Protocol". Nonetheless, every guy behind the counter in a booth at OSH will point to HIS recharge curve and compare it with the recharge curve for the charger being sold across the isle and do his best to convince you that HIS is better. This is sort of like water districts of various cities extolling the virtues of THEIR water treatment by taking swipes at each other. They ignore the fact that only in the last 100 years or so of mankind's existence on the planet has the threat of water-borne disease become non-existent because of our understanding of simple-ideas that have nothing to do with hardness, taste, or perhaps even clarity of the product. And so it is with battery chargers. They're all so good compared to what we had 20 years ago that the only thing they can do is snipe at each other! > What is the AA, just a tenth of an amp or so lower setting, or is it magic? Not sure about what you're asking. Are you wondering what test currents are appropriate for testing AA cells? Depends on the technology. We know that the higher the load, the lower the apparent capacity due to internal losses in the cell. The discharge current selected for testing purposes has to do with the application in which you choose to use the product. For example, a wrist watch runs on fractions of microamps so you can get most of the energy out of that itty-bitty button cell in spite of it's 'horrendous' internal impedance. On the other hand, my digital camera with the big LCD color screen needs 500 mA or more of supply current. In this case, performance is optimized by selecting cells with the lowest practical resistance which is not necessarily the cell with the greatest capacity. I did all the tests on alkaline cells with 5 ohm load http://www.aeroelectric.com/articles/AA_Bat_Test.pdf . . . which was in the ball-park for various applications and consistent from test to test so that the brands could be compared. This suite of tests was run on AA cells at 300 mA constant current: http://www.aeroelectric.com/Pictures/Curves/AA_Battery_Tests_80322.jpg Again, the current needed to be consistent from test to test and in the ball-park for the applications (digital cameras). However, if you ran this same array of cells at say, 20 mA discharge rates, you'd get a LOT more total energy out of them. Bob . . . ________________________________ Message 3 _____________________________________ Time: 10:14:08 AM PST US From: "Bob Verwey" Subject: AeroElectric-List: Regulated voltage to high Hi folks I have had to come out of perpetual lurk on account of my little problem. I have a recently OH 12 v Delco Remy alternator on an IO470 experimental setup with a Motorola electronic automotive type regulator. The regulated voltage is 14.6v steady. I also changed the battery and some wiring (relay for the field switch, which works off the Cessna type split master). I previously had a wig wag ammeter, ostensibly due to wiring not being what it should be, or sensing in the incorrect place. Is it possible to "adjust" this voltage somehow? Bob Verwey A35 Bonanza ZU-DLW ________________________________ Message 4 _____________________________________ Time: 12:08:41 PM PST US From: Ed Holyoke Subject: Re: AeroElectric-List: A Tale of Two Batteries Bob, What I was asking about was the VDC 12248-AA-1 charger as compared to the straight 12248. I think the "aviation adjusted" charger runs a couple of tenths of a volt (I misspoke when I said amp) lower to make Concorde and Gill happy. I was asking if it really makes much difference in the life of the battery - $65 worth. I'm guessing from your test curves and stuff that the answer is probably no. The 12248 will also do flooded batteries where the AA-1 is AGM only. Pax, Ed Holyoke Robert L. Nuckolls, III wrote: > > >> What is the AA, just a tenth of an amp or so lower setting, or is it >> magic? > > > Not sure about what you're asking. Are you wondering what > test currents are appropriate for testing AA cells? > > ________________________________ Message 5 _____________________________________ Time: 06:21:23 PM PST US From: "Carlos Trigo" Subject: AeroElectric-List: Transponder and Radio position Hi there Folks I am about to begin the installation of the Transponder (GTX-330) and the Comm Radio (SL-30) in my RV-9A's panel, and I wonder if there is any rule of thumb about their position in the central rack. In panels that I have seen, the Xpdr is usually at the bottom position, with the Radio immediately above. Which are the pros and cons of putting those 2 avionics at the bottom of the rack, and the Xpdr below or above the Radio? Carlos ________________________________ Message 6 _____________________________________ Time: 06:25:47 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: A Tale of Two Batteries At 12:01 PM 9/28/2008 -0700, you wrote: > >Bob, > >What I was asking about was the VDC 12248-AA-1 charger as compared to the >straight 12248. I think the "aviation adjusted" charger runs a couple of >tenths of a volt (I misspoke when I said amp) lower to make Concorde and >Gill happy. I was asking if it really makes much difference in the life of >the battery - $65 worth. I'm guessing from your test curves and stuff that >the answer is probably no. The 12248 will also do flooded batteries where >the AA-1 is AGM only. Aha! I'm not familiar with those chargers . . . but yes, a few tenths here, a few tenths there is probably not significant in the grand scheme of things. I'd like to know the definition of "aviation adjusted" . . . and the rationale for making the distinction. Bottom line is that NO AIRPLANE in service even approximates the fondest wishes of a manufacturer for the care and feeding of their particular baby. So if you've got a top-off charger that drops down to within a half a volt of open circuit voltage, it's just fine. Bob . . . ________________________________ Message 7 _____________________________________ Time: 06:37:33 PM PST US From: "Sam Hoskins" Subject: Re: AeroElectric-List: Transponder and Radio position >From the ergonomics point of view, you would position things by how much you have to use them. Since you "use" a transponder less than a com radio, the com would get preference in the battle of the easiest reach. Sam Hoskins www.samhoskins.blogspot.com On Sun, Sep 28, 2008 at 8:20 PM, Carlos Trigo wrote: > Hi there Folks > > > I am about to begin the installation of the Transponder (GTX-330) and the > Comm Radio (SL-30) in my RV-9A's panel, and I wonder if there is any rule of > thumb about their position in the central rack. > > In panels that I have seen, the Xpdr is usually at the bottom position, > with the Radio immediately above. > > Which are the pros and cons of putting those 2 avionics at the bottom of > the rack, and the Xpdr below or above the Radio? > > > Carlos > > > * > > * > > ________________________________ Message 8 _____________________________________ Time: 09:05:15 PM PST US From: James Robinson Subject: AeroElectric-List: Re: capacitance probes Hi Bob I have a question regarding capacitance fuel probes.- I am having a fuel level reading on my lt tank that was fluxuating and is now reading zero. I am trying to narrow the problem.- Probes, analog to digital converter/ wi ring / EngineAirdataUnit- EAU.- My first thing to eliminate is the prob e.- It has 3 wires red-black-white if that helps. Jim Robinson Glll- N79R ------------------------------------------------------------------------------------- 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.