---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 11/03/05: 19 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:27 AM - Re: shielded wire installation (Robert L. Nuckolls, III) 2. 06:42 AM - Re: Re: Charging two batteries (Hinde, Frank George (Corvallis)) 3. 06:53 AM - Re: Charging two batteries (Robert L. Nuckolls, III) 4. 07:36 AM - Re: Re: Charging two batteries (Robert L. Nuckolls, III) 5. 07:36 AM - Re: Charging two batteries (Hinde, Frank George (Corvallis)) 6. 08:12 AM - Re: Re: Charging two batteries (Hinde, Frank George (Corvallis)) 7. 09:26 AM - Samlex Power Supply (Jon & Kathryn Hults) 8. 11:46 AM - Suzuki Samuri Alternator (NEW) () 9. 11:48 AM - Re: Re: Charging two batteries (Robert L. Nuckolls, III) 10. 12:26 PM - Re: Samlex Power Supply (Robert L. Nuckolls, III) 11. 01:48 PM - Understanding Alternators (Robert L. Nuckolls, III) 12. 04:18 PM - Re: Understanding Alternators (Bob McCallum) 13. 04:55 PM - Re: Charging two batteries (Joe Dubner) 14. 05:11 PM - kt 78 single row plug and contacts (Bill and Marsha) 15. 06:45 PM - help the non-believers (Dan Checkoway) 16. 07:46 PM - Re: Understanding Alternators (Robert L. Nuckolls, III) 17. 07:55 PM - Re: help the non-believers (Robert L. Nuckolls, III) 18. 08:13 PM - Re: Re: Charging two batteries (Robert L. Nuckolls, III) 19. 08:50 PM - Re: Welding Cable AWG 2 (jerb) ________________________________ Message 1 _____________________________________ Time: 06:27:54 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: shielded wire installation --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 03:29 PM 11/2/2005 -0800, you wrote: >--> AeroElectric-List message posted by: Erich_Weaver@URSCorp.com > >greetings > >Stupid questions from the electrically challenged: > >Recently received a strobe system from Creativ Air. The bundled wire >supplied for the task includes a bare wire that I presume is associated >with the surrounding thin foil shield. No instructions provided for the >bare wire. Does it get connected to ground along with the normal insulated >ground wire or just float unconnected? If connected to ground, does it >matter whether just one end or both ends of it are connected? And exactly >what am I actually protecting myself from here? Isnt shielding pretty >limited in what it can do? As long as the shield conductor is not ALSO being used as a power carrying conductor, the CURRENT that will flow in the shield is exceedingly small . . . Shielding is a propagation breaker for ELECTROSTATICALLY conducted noise which is present only in proximity to high voltage, fast moving waveforms (like those found in the strobe wiring). It has no value for de-coupling MAGNETICALLY conducted noise (twisted pairs do that best). The bare wire under the shield IS indeed intended for making electrical connection to the aluminum foil shield. You attach this wire (or an extension of this wire) to the case of the strobe at the mounting feet. Having said that, should you allow this shield to go un-connected, it's unlikely that you'll perceive any increase in strobe noise in any other system . . . the wires that are typically bundled with strobe heads are not potential victims. >One more: the provided individual strobe wires are 22 awg. Seemed small >to me, but I believe thats good for 5 amps, and looking at the system specs >and the wire chart, that should work for this system. But dont the strobe >trigger wires have really high voltage, maybe even in the low thousands of >volts? Isnt there a limit to the voltage a wire can carry as well as the >amps? Should I be concerned?What say the list? Wire AWG sets the temperature rise on a wire when carrying steady state current. The current limit is set by how much heat the INSULATION can stand -OR- your limits on system voltage drop at the current of interest . . . whichever is more restrictive. The INSULATION is also tasked with keeping the volts inside the wire. The popular M22759/16 Tefzel wire is rated for 600V service. I don't recall but the Beldfoil shielded twisted trio used in most strobe systems is rated for 600V too . . . voltage to power the strobe bulb is on the order of 300V. The bulb may have a peak power draw on the order of 1000 to 2000 watts. A 2,000 watt peak power draw is about 6.6 amps at 300v, well within the capabilities of the 22AWG wire. Bob . . . ________________________________ Message 2 _____________________________________ Time: 06:42:45 AM PST US Subject: RE: AeroElectric-List: Re: Charging two batteries From: "Hinde, Frank George (Corvallis)" --> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" Now you tell me...:) Guess I have a HF battery charger for the lawn tractor now! Frank -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Joe Dubner Subject: AeroElectric-List: Re: Charging two batteries --> AeroElectric-List message posted by: Joe Dubner On 02-Nov-05 14:37 Hinde, Frank George (Corvallis) wrote: > --> AeroElectric-List message posted by: "Hinde, Frank George > --> (Corvallis)" > > Just bought one for $24 plus shipping off EBAY...My little harbor > freight charger was still about .25V low for a continuous trickle to > my Odyssey battery even after 2 days. > > Thanks...Spend the money do the right thing and forget about it!...:) > > Frank The Harbor Freight "battery maintainer" is adjustable, you know. At least the old models were although a friend recently bought one that had a fixed voltage output. The unit is nothing more than a current-limited constant-voltage power supply using a 7805 regulator and a handful of discrete components. Adjusting it involves opening up the housing and tweaking a small pot while measuring the no-load output on an accurate voltmeter. 13.5 volts is about right IMO. Seems like a lot of value for about $10 on sale. -- Joe Joe Dubner Long-EZ 821RP Lewiston, ID http://www.nicon.org/chapter328/jd/ ________________________________ Message 3 _____________________________________ Time: 06:53:01 AM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Charging two batteries --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 02:37 PM 11/2/2005 -0800, you wrote: >--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" > > >Just bought one for $24 plus shipping off EBAY...My little harbor >freight charger was still about .25V low for a continuous trickle to my >Odyssey battery even after 2 days. > >Thanks...Spend the money do the right thing and forget about it!...:) > >Frank I would counsel adoption of some term other than "trickle charge" for the modern maintenance of batteries. I days of yore, a "trickle charge" was defined as some steady state, CONSTANT CURRENT charge that was deemed too low to be detrimental to the battery but sufficient to offset the battery's inherent self-discharge rate. Flooded batteries had about a .5 to 1% per day self discharge rate. So a 30 a.h. car battery REALLY needed 5 to 20 MILLIAMPS of input current to offset internal losses. "Trickle chargers" were typically in the .5 to 1.0 ampere range. So, under trickle-charge maintenance, a flooded battery could be expected to consume water which was easily replaced. The SVLA/RG battery cannot be so maintained and a true trickle- charge will cook them. So, a new approach is needed. If you set a fully charged batter on the shelf and come back to measure its terminal voltage after 24 hours, it will be on the order of 12.8 volts. Okay, this is the voltage at which internal losses are being supplied. Suppose we hook a 13.0 volt power supply to the battery. This voltage is way too low to do any chemical conversions, i.e. CHARGE the battery. However, it make the power supply the higher and therefore dominant power source in the system . . . it WILL assume ALL parasitic loads in the system thereby causing all self discharging of the battery to cease. The battery maintainer product DO have a charge mode. The Battery Tender Juniors will put out about .75A in the charge mode. I use them to charge my really big instrumentation batteries after a test run . . . it might take it a day or two to bring up a depleted battery . . . but then it drops to 13.0 CONSTANT VOLTAGE maintenance mode and sustains the battery in a ready state indefinitely . . . but it's NOT a trickle- charger. Bob . . . ________________________________ Message 4 _____________________________________ Time: 07:36:02 AM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Re: Charging two batteries --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 06:41 AM 11/3/2005 -0800, you wrote: >--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" > > >Now you tell me...:) > >Guess I have a HF battery charger for the lawn tractor now! > >Frank > > >The Harbor Freight "battery maintainer" is adjustable, you know. At >least the old models were although a friend recently bought one that had >a fixed voltage output. The unit is nothing more than a current-limited >constant-voltage power supply using a 7805 regulator and a handful of >discrete components. > >Adjusting it involves opening up the housing and tweaking a small pot >while measuring the no-load output on an accurate voltmeter. 13.5 volts >is about right IMO. > >Seems like a lot of value for about $10 on sale. I've tested a couple of HF "maintainers" and only one of the three was truly suited to the task. The acid test is to come back in two or three days after the battery was placed in 'storage' on the maintainer and measure the battery terminal voltage. It should be greater than 13.0 and less than 13.5 with 13.0 being the preferred end of the spectrum. Two devices I tested were running 14.2 and 13.8 volts. The 13.8 would probably have been okay but the 14.2 was definitely too high. If you have some control over the product via potentiometer adjustment, great. Shoot for 13.0 Bob . . . ________________________________ Message 5 _____________________________________ Time: 07:36:33 AM PST US Subject: RE: AeroElectric-List: Charging two batteries From: "Hinde, Frank George (Corvallis)" --> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" Cool!...Thanks for the education Bob Frank RV7A (IFR) Wiring DONE, Done...And thankfully DONE! Do not archive -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Subject: RE: AeroElectric-List: Charging two batteries --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" --> At 02:37 PM 11/2/2005 -0800, you wrote: >--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" > > >Just bought one for $24 plus shipping off EBAY...My little harbor >freight charger was still about .25V low for a continuous trickle to my >Odyssey battery even after 2 days. > >Thanks...Spend the money do the right thing and forget about it!...:) > >Frank I would counsel adoption of some term other than "trickle charge" for the modern maintenance of batteries. I days of yore, a "trickle charge" was defined as some steady state, CONSTANT CURRENT charge that was deemed too low to be detrimental to the battery but sufficient to offset the battery's inherent self-discharge rate. Flooded batteries had about a .5 to 1% per day self discharge rate. So a 30 a.h. car battery REALLY needed 5 to 20 MILLIAMPS of input current to offset internal losses. "Trickle chargers" were typically in the .5 to 1.0 ampere range. So, under trickle-charge maintenance, a flooded battery could be expected to consume water which was easily replaced. The SVLA/RG battery cannot be so maintained and a true trickle- charge will cook them. So, a new approach is needed. If you set a fully charged batter on the shelf and come back to measure its terminal voltage after 24 hours, it will be on the order of 12.8 volts. Okay, this is the voltage at which internal losses are being supplied. Suppose we hook a 13.0 volt power supply to the battery. This voltage is way too low to do any chemical conversions, i.e. CHARGE the battery. However, it make the power supply the higher and therefore dominant power source in the system . . . it WILL assume ALL parasitic loads in the system thereby causing all self discharging of the battery to cease. The battery maintainer product DO have a charge mode. The Battery Tender Juniors will put out about .75A in the charge mode. I use them to charge my really big instrumentation batteries after a test run . . . it might take it a day or two to bring up a depleted battery . . . but then it drops to 13.0 CONSTANT VOLTAGE maintenance mode and sustains the battery in a ready state indefinitely . . . but it's NOT a trickle- charger. Bob . . . ________________________________ Message 6 _____________________________________ Time: 08:12:23 AM PST US Subject: RE: AeroElectric-List: Re: Charging two batteries From: "Hinde, Frank George (Corvallis)" --> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" I am assuming you measure the battery volts with the charger/maintainer still connected after two or three days?? Thanks Frank -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Subject: RE: AeroElectric-List: Re: Charging two batteries --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" --> At 06:41 AM 11/3/2005 -0800, you wrote: >--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" > > >Now you tell me...:) > >Guess I have a HF battery charger for the lawn tractor now! > >Frank > > >The Harbor Freight "battery maintainer" is adjustable, you know. At >least the old models were although a friend recently bought one that >had a fixed voltage output. The unit is nothing more than a >current-limited constant-voltage power supply using a 7805 regulator >and a handful of discrete components. > >Adjusting it involves opening up the housing and tweaking a small pot >while measuring the no-load output on an accurate voltmeter. 13.5 >volts is about right IMO. > >Seems like a lot of value for about $10 on sale. I've tested a couple of HF "maintainers" and only one of the three was truly suited to the task. The acid test is to come back in two or three days after the battery was placed in 'storage' on the maintainer and measure the battery terminal voltage. It should be greater than 13.0 and less than 13.5 with 13.0 being the preferred end of the spectrum. Two devices I tested were running 14.2 and 13.8 volts. The 13.8 would probably have been okay but the 14.2 was definitely too high. If you have some control over the product via potentiometer adjustment, great. Shoot for 13.0 Bob . . . ________________________________ Message 7 _____________________________________ Time: 09:26:38 AM PST US Subject: AeroElectric-List: Samlex Power Supply From: Jon & Kathryn Hults --> AeroElectric-List message posted by: Jon & Kathryn Hults Bob, I bought one of the Samlex 13.8 VDC power supplies you had on the list a few weeks ago to hook up to my airplane during install/troubleshooting/training of my avionics. My question is: It didn't come with output cables, so what sort of cables/wires should I use and where on the airplane should I attach them to power the airplane's electrical system? Attach to the fat wires on the battery? Disconnect the battery first? Thought I'd ask before just connecting it with all those radios at stake! Thanks, Jon Hults Lancair Legacy ________________________________ Message 8 _____________________________________ Time: 11:46:46 AM PST US From: Subject: AeroElectric-List: Suzuki Samuri Alternator (NEW) --> AeroElectric-List message posted by: >From: "LarryRobertHelming" >Subject: Suzuki Samuri Alternator > >--> AeroElectric-List message posted by: "LarryRobertHelming" > >Charlie Kuss: How does anyone check the rectifier diodes? I ask this >because I have looked at a failed alternator (different type '77 honda >civic) and what I think might be the diodes seem to be soldered to the >surrounding casing material. Any help would be appreciated. Thanks. > >Indiana Larry Larry: I can help you with info on how to check, repair, replacement parts but my first suggestion is just replace it with a new unit. BUY NEW: I can tell you where to get a BRAND NEW 55 amp ND (Suzuki Samurai/Sidekick, Chev Sprint) alternator for $95 plus shipping. Write me for info if you want. By the time you buy individual components (retail) and spend the time replacing parts, it is easier buy new if you can get a good price. This price is cheaper than a rebuild . The list on a rebuild is almost $200, the $95 is a sale price. This is what I have bought them for before. This is a NEW Nippondenso alternator. Sometimes new alternators come on eBay also. Most of us can't buy wholesale direct from large wholesalers of parts, unless you know where to look. One place, I know of, will sell to individuals (without hassle). They are the ones I referred to above, who have new units for a great price from time to time. It is worth a try. No guarantee's since it was a October sale, but it's worth a call. They repeat sales all the time. Even if you can buy and replace a few parts, you have an alternator with other old components of unknown service time (e.g., bearings). I also don't think you should just willy-nilly replace parts on a guess. Let me know if you want a new unit. Also did you have a OV module tied to the thing? IF YOU WANT TO REPAIR HERE IS SOME INFO Here is a great source of info on the web on how to trouble shoot the charging system on a Toyota, which happens to be a ND alternator of similar design. http://www.autoshop101.com/ (Under Technical Articles, Item 08: Toyota Charging Systems) You can test the diodes (rectifier) can be checked with an ohmmeter. Many Ohmmeters have a diode check function (see: ref page 19). You are just checking for an open or short. A better test is spinning the unit under load with an oscilloscope to determine rectifier state (see: ref above page 18). PART NUMBERS Here are some part numbers and can can go to a local auto electric shop. Remember there are after market and original ND parts. Large after market part manufactures are Transpo, ASE and Laster. I assume you have a: Alternator - Nippondenso IR/IF 55 Amp, 12 Volt, CW, 1-Groove Pulley Used On: (1988-87) Chevrolet Sprint 1.0L (1995-86) Suzuki Samurai 1.3L (1989) Suzuki Sidekick 1.3L Replaces: Nippondenso 100211-141, 100211-155, 100211-407 Lester Nos: 14684 -Replacement Rectifier unit: 31-8200 Rectifier For: Nippondenso 45-60 Amp IR/IF Alternators w/ 100mm OD Stator Used On: (1998-85) Suzuki, Toyota Replaces: Nippondenso 021580-3130, -4340 Unit Nos: Nippondenso 100211-155, 100211-407 Lester Nos: 14684 Dimensions: 88mm OD M6 x 1.0 Battery Terminal Notes: Similar to 31-8221 except position of stator lead mtg. holes not interchangeable Components: 32-8909 Negative Diode 32-8910 Positive Diode Features: Renard 20 Amp/200 Volt, dish diodes Also consider: INR724 Rectifier, Transpo -OR- INR724 (Ref. Num. 31-8200) Rectifier (Transpo part number) For: Nippondenso 45-60 Amp IR/IF Alternators w/ 100mm OD Stator Used On: (1998-85) Suzuki, Toyota Replaces: Nippondenso 021580-3130, -4340 Toyota 27357-11170, -72150 Unit Nos: Nippondenso 100211-155, 100211-407 Lester Nos: 14684 Dimensions: 90mm OD M6 x 1.0 x 44mm Battery Terminal Features: Transpo 8-dish diodes, 40 amp (The INR724 appears to be an upgraded after market unit). -Replacement Regulator: 5-8205-3 (Ref. Num. IN221-1) Regulator 12 Volt, A-Circuit, D-IG-L Terminals For: Nippondenso IR/IF Alternators Used On: (1995-84) Chevrolet, Geo, Honda, Isuzu, Suzuki Replaces: Nippondenso 126000-0410, -0430 Suzuki 32500-82610 Unit Nos: Nippondenso 100211-141 Lester Nos: 14684Dimensions: 64mm Mtg. Length Notes: L-terminal is an output terminal. Similar to 35-8226-1 except 35-8226-1 w/ LRC feature. Components: 35-8205-5 Repair Circuit Features: Short-circuit protection of lamp and field circuits Also consider: 35-8205-5 Repair Circuit -Aftermarket REGULATOR UNIT- Regulator 12 Volt, A-Circuit, D-IG-L Terminals For: Nippondenso IR/IF Alternators Used On: (1995-86) Daihatsu, Suzuki Replaces: Nippondenso 126000-0720, -0721, -1330 Suzuki 32500-86510, -86511 Unit Nos: Nippondenso 100211-155, 100211-407 Lester Nos: 14684 Dimensions: 57.5mm Mtg. Length Notes: L-terminal is not an output terminal. Similar to 35-8216 except 35-8216 L-terminal is an output terminal. Components: 35-8215-5 Repair Circuit Features: OE approved Short-circuit protection of field circuit Also consider: 35-8215-5 Repair Circuit IN253 Regulator, Transpo THE ENTIRE BRUSH ASSY Brush Holder Assy. (holder, cover, brushes) For: Nippondenso IR/IF Alternators Used On: (2004-86) Acura, Chevrolet, Geo, Honda, Isuzu, Jaguar, Lexus, Mazda, Toyota, Volvo Replaces: Nippondenso 021620-2530, 021620-2720 Toyota 27370-42010, 27370-75060 Lester Nos: 13684 Notes: Used w/ 41-82306 seal, 41-82101 gasket Components: 38-8201 Brush 46-82400 Plastic Cover Features: Best Value Also consider: 39-8203 Brush Holder Assy IF YOU JUST WANT TO REPLACE BRUSHES Brush 12 Volt For: Nippondenso ER/IF, IR/IF Alternators Used On: (2002-83) Acura, Chevrolet, Chrysler, Daihatsu, Dodge, Eagle, Geo, Honda, Isuzu, Jaguar, Jeep, Lexus, Mazda, Plymouth, Sterling, Suzuki, Toyota, Volvo; Toyota Lift Truck Lester Nos: 13684 Dimensions: 5mm T x 7mm W x 15mm L x 48mm LL Good Luck Larry. I think new is the way to go. It will likely be the last alternator you buy for this plane. Again suggest you keep some ducted air directed toward the back, DON'T cycle the alternator ON/OFF while under load (spinning) and if at all possible buy new units as opposed to rebuilds. George --------------------------------- ________________________________ Message 9 _____________________________________ Time: 11:48:55 AM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Re: Charging two batteries --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 08:11 AM 11/3/2005 -0800, you wrote: >--> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" > > >I am assuming you measure the battery volts with the charger/maintainer >still connected after two or three days?? > >Thanks Yes. The point is to confirm that it's a REAL maintainer and NOT a trickle-charger (or poorly crafted maintainer). Bob . . . ________________________________ Message 10 ____________________________________ Time: 12:26:57 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Samlex Power Supply --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 09:24 AM 11/3/2005 -0800, you wrote: >--> AeroElectric-List message posted by: Jon & Kathryn Hults > > >Bob, > >I bought one of the Samlex 13.8 VDC power supplies you had on the list a few >weeks ago to hook up to my airplane during install/troubleshooting/training >of my avionics. > >My question is: It didn't come with output cables, so what sort of >cables/wires should I use and where on the airplane should I attach them to >power the airplane's electrical system? Attach to the fat wires on the >battery? Disconnect the battery first? > >Thought I'd ask before just connecting it with all those radios at stake! You need some nice soft, fat-wire but smaller than 4AWG welding cable (although the welding cable is cheap, easy to get and easy to work with). When I was selling that supply, I also offered a cable assembly that could be used to covey the 25A from power supply to aircraft. I suggested that the power supply be attached to the airplane alternator's B-lead connection. This way, the power supply emulates the alternator even to the extent that it will charge the battery and allow the entire system to be up and running as if it were being supplied by an alternator running with just enough RPM to put out 25A. I fabricated this jumper from a 10 AWG speaker cable with to conductors paired like lamp cord. Very flexible and pleasant to work with. I even suggested that one might wish to build up a little switching box with an AC outlet on it and a short AC power cord. The box contained a 12v relay good for 120VAC at 10A or so. The relay is used to control 120 VAC going into the power supply. The relay's coil leads are brought out to a connector and wired to the airplane such that the relay coil can be energized from the same switch that turns the alternator on or off from the panel. Except for available power output, this arrangement provides an AC mains supplied, alternator emulator that permits things to work in from the pilot's seat just as if the engine were running. One builder wrote me telling about a potentiometer he found inside his power supply that allowed adjustment of the output voltage up to 14.2 . . . cool but not terribly necessary. These supplies are pretty bullet proof, well regulated and very well filtered. You can run ship's goodies from these supplies with or without the battery in the system. Bob . . . ________________________________ Message 11 ____________________________________ Time: 01:48:53 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Understanding Alternators --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" As I promised for last weekend, here are the first pages of an introduction leading up to a series of repeatable experiments designed to discover the operating characteristics of alternators. As always, considered critical review welcome. http://www.aeroelectric.com/articles/alternators/UA/Alternators_1.html I've got the next 4 pages roughed out. Will try to get them up in the next week or so. Bob . . . ________________________________ Message 12 ____________________________________ Time: 04:18:38 PM PST US From: "Bob McCallum" Subject: Re: AeroElectric-List: Understanding Alternators --> AeroElectric-List message posted by: "Bob McCallum" Bob; Being VERY picky, but you asked for criticism. I believe in your second paragraph of this article where you state "Further, even the largest automotive alternators require the brushes to carry more than 3 or four amps." , that you actually mean "no more than 3 or 4 amps." Bob McC ----- Original Message ----- From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Understanding Alternators > --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > > As I promised for last weekend, here are the first > pages of an introduction leading up to a series > of repeatable experiments designed to discover > the operating characteristics of alternators. > > As always, considered critical review welcome. > > http://www.aeroelectric.com/articles/alternators/UA/Alternators_1.html > > I've got the next 4 pages roughed out. Will try to get > them up in the next week or so. > > Bob . . . > > ________________________________ Message 13 ____________________________________ Time: 04:55:17 PM PST US From: Joe Dubner Subject: AeroElectric-List: Re: Charging two batteries --> AeroElectric-List message posted by: Joe Dubner I agree with Frank Hinde's sentiment: thanks for the education, Bob. My comments follow this segment of your message. On 03-Nov-05 07:34 Robert L. Nuckolls, III wrote: [snip] > > I've tested a couple of HF "maintainers" and only one of the three > was truly suited to the task. The acid test is to come back in two or > three days after the battery was placed in 'storage' on the maintainer > and measure the battery terminal voltage. It should be greater than 13.0 > and less than 13.5 with 13.0 being the preferred end of the spectrum. > > Two devices I tested were running 14.2 and 13.8 volts. The 13.8 would > probably have been okay but the 14.2 was definitely too high. If you > have some control over the product via potentiometer adjustment, great. > Shoot for 13.0 FWIW and just as a data point, I hooked up a 12V 4AH SLA battery to a regulated power supply set to 13.5V (to simulate a Harbor Freight "battery maintainer"). The battery was fully charged but had been sitting around for a couple of weeks. After a few seconds the battery drew about 40 ma. (.01C). After about an hour the charge rate was down to 10 ma. (.0025C ?) and appears to be "trickling" downward (pun intended :-). This is the point where I'd normally remove it from the "charger" (or at my first noticing this near-zero charge rate if it was on the charger overnight). But I'd feel comfortable about leaving it there indefinitely in accordance with the chart printed on the battery housing: Application: Voltage: Current: ----------- ------- ------- Standby 13.5 - 13.8 No Limit Cycle Use 14.4 - 15.0 0.3 Capacity This may or may not be representative of SLA batteries intended to start and power our aircraft but it's how I typically charge my non-aircraft SLA batteries. -- Joe Joe Dubner Long-EZ 821RP Lewiston, ID http://www.nicon.org/chapter328/jd/ ________________________________ Message 14 ____________________________________ Time: 05:11:46 PM PST US From: "Bill and Marsha" Subject: AeroElectric-List: kt 78 single row plug and contacts --> AeroElectric-List message posted by: "Bill and Marsha" Does anyone know the Molex part nombers for the plug and contacts for a KT 78 Transponder? Thanks Bill ________________________________ Message 15 ____________________________________ Time: 06:45:21 PM PST US From: "Dan Checkoway" Subject: AeroElectric-List: help the non-believers --> AeroElectric-List message posted by: "Dan Checkoway" http://www.vansairforce.com/community/showthread.php?t=3810 (see the last few posts regarding strobe & antenna runs in the same conduit) They're implying that I got "lucky" having run my landing light wires, position light wires, and shielded strobe wires right next to my shielded RG400 antenna runs in the same conduit run. I have no strobe noise in my system and they think it's because I am lucky, rather than because I properly shielded, grounded shields properly, and grounded my audio systems and other toys properly (as per Bob's and others' good advice). I'm not an electrical engineer and have limited understanding of "invisible" concepts such as induced noise, right hand rule, whatever. I don't know the deep technical explanation behind why shielding works, nor can I fully explain to a non-believer why something that is not properly shielded may be noisy. But I have a feeling it's not luck at work in my case. Maybe Bob or somebody knowledgeable on this list can poke in on this thread and be the voice of reason. If you can't post there, feel free to email me (here or off-list, doesn't matter) and I'll re-post your wisdom on the VAF Forums. do not archive )_( Dan RV-7 N714D (661 hours) http://www.rvproject.com ________________________________ Message 16 ____________________________________ Time: 07:46:22 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Understanding Alternators --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 07:14 PM 11/3/2005 -0500, you wrote: >--> AeroElectric-List message posted by: "Bob McCallum" > > >Bob; > >Being VERY picky, but you asked for criticism. I believe in your second >paragraph of this article where you state "Further, even the largest >automotive alternators require the brushes to carry more than 3 or four >amps." , that you actually mean "no more than 3 or 4 amps." > >Bob McC Yes! Thank you. Bob . . . ________________________________ Message 17 ____________________________________ Time: 07:55:00 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: help the non-believers --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 06:45 PM 11/3/2005 -0800, you wrote: >--> AeroElectric-List message posted by: "Dan Checkoway" > >http://www.vansairforce.com/community/showthread.php?t=3810 > >(see the last few posts regarding strobe & antenna runs in the same conduit) > >They're implying that I got "lucky" having run my landing light wires, >position light wires, and shielded strobe wires right next to my shielded >RG400 antenna runs in the same conduit run. I have no strobe noise in my >system and they think it's because I am lucky, rather than because I >properly shielded, grounded shields properly, and grounded my audio systems >and other toys properly (as per Bob's and others' good advice). > >I'm not an electrical engineer and have limited understanding of "invisible" >concepts such as induced noise, right hand rule, whatever. I don't know the >deep technical explanation behind why shielding works, nor can I fully >explain to a non-believer why something that is not properly shielded may be >noisy. But I have a feeling it's not luck at work in my case. Engineers that depend on luck don't stay employed very long. >Maybe Bob or somebody knowledgeable on this list can poke in on this thread >and be the voice of reason. If you can't post there, feel free to email me >(here or off-list, doesn't matter) and I'll re-post your wisdom on the VAF >Forums. I was tempted . . . but getting involved in lots of different forums that soaked up so many hours of not-so-spare time. I think I'll pass on this one! There are probably dozens of forums that propagate poor science . . . can't help them all. Bob . . . ________________________________ Message 18 ____________________________________ Time: 08:13:31 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Charging two batteries --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > >FWIW and just as a data point, I hooked up a 12V 4AH SLA battery to a >regulated power supply set to 13.5V (to simulate a Harbor Freight >"battery maintainer"). The battery was fully charged but had been >sitting around for a couple of weeks. After a few seconds the battery >drew about 40 ma. (.01C). After about an hour the charge rate was down >to 10 ma. (.0025C ?) and appears to be "trickling" downward (pun >intended :-). Good data! I just checked one of my big-honker 32 a.h. batteries that's been setting on a Battery Tender for several weeks. Terminal voltage with Battery Tender connected was 13.1 volts. I checked the "charging current" out of the battery tender and it was stroking along at the grand total of 560 MICROAMPS! I think this is a good measurement of that battery's internal self-discharge current. If allowed to set un-supported, we can guess that it would toss off about 1/2 it's capacity in about 3.6 years. >This is the point where I'd normally remove it from the "charger" (or at >my first noticing this near-zero charge rate if it was on the charger >overnight). But I'd feel comfortable about leaving it there >indefinitely in accordance with the chart printed on the battery housing: > >Application: Voltage: Current: >----------- ------- ------- >Standby 13.5 - 13.8 No Limit >Cycle Use 14.4 - 15.0 0.3 Capacity > >This may or may not be representative of SLA batteries intended to start >and power our aircraft but it's how I typically charge my non-aircraft >SLA batteries. There isn't a great deal of difference in the various "styles" of Lead-Acid batteries. There was a bit of a dust up over mis-interpreted specifications a few months back that prompted this critical review of some published documents: http://www.aeroelectric.com/articles/Batteries/Deltran_Odyssey_Floobydust.html Battery Tender type gizmos will top-off an SLA battery at the "cycle use" voltage levels and then drop back to a maintenance level that is below that of the "standby" levels. See: http://batterytender.com/includes/languages/english/resources/Product_Info_BT_Junior.pdf Slick gizmos. Bob . . . ________________________________ Message 19 ____________________________________ Time: 08:50:00 PM PST US From: jerb Subject: Re: AeroElectric-List: Welding Cable AWG 2 --> AeroElectric-List message posted by: jerb I think the big issue with jumper cable grade of wire is its insulation, the insulation may be tough but it probably would burn pretty well. I wouldn't use it for that reason alone, buy welding cable it made for hard use and resist burning. Also jumper cable tends to use larger stands twisted into a conductor where welding cable is fine strands proving be more tolerant to vibration and flexing that takes place on aircraft. jerb At 11:39 PM 10/30/2005, you wrote: >--> AeroElectric-List message posted by: "Chris Byrne" > > >Listers > >Just a thought. >Would the cable from high quality Jump Start leads be suitable for the short >runs to the starter etc in place of welding cable. >Ther are good and bad jump start cables. I have a good one and would be a >good source if suitable. > >Chris Byrne >Sydney > >