---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Wed 05/27/09: 21 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 06:37 AM - Re: Engine mount as starter ground path (Robert L. Nuckolls, III) 2. 06:37 AM - KX-125 Installation Manual? (jf3sb) 3. 07:15 AM - Re: AeroElectric-List Digest: 21 Msgs - 05/26/09 (Johnson, Phillip (EXP)) 4. 07:21 AM - SEC-1223 Power Supply --Question re isolating diode and charge limiting resistor (DCS317@aol.com) 5. 07:46 AM - Re: KX-125 Installation Manual? (Werner Schneider) 6. 09:21 AM - Grounding philosophy (Robert L. Nuckolls, III) 7. 09:29 AM - SEC-1223 Power Supply (Robert L. Nuckolls, III) 8. 10:03 AM - Re: Grounding philosophy (Matt Prather) 9. 11:03 AM - Re: Engine mount as starter ground path (Lincoln Keill) 10. 11:13 AM - Re: Engine mount as starter ground path (Bill Mauledriver Watson) 11. 12:11 PM - DynaFocal engine mount ring (Bill Bradburry) 12. 12:25 PM - Re: Engine mount as starter ground path (David LLoyd) 13. 01:06 PM - Alternator with built-in regulator (Wade Roe) 14. 01:43 PM - Re: Alternator with built-in regulator (Hinde, Frank George (Corvallis)) 15. 02:23 PM - State of the art - then and now (Robert L. Nuckolls, III) 16. 02:23 PM - Re: Alternator with built-in regulator (Wade Roe) 17. 02:30 PM - Re: Alternator with built-in regulator (Robert L. Nuckolls, III) 18. 02:37 PM - Re: Re: Engine mount as starter ground path (Robert L. Nuckolls, III) 19. 02:52 PM - Re: Alternator with built-in regulator (Hinde, Frank George (Corvallis)) 20. 08:40 PM - Re: Alternator with built-in regulator (Robert L. Nuckolls, III) 21. 08:41 PM - Military_Humor_Miss_America_1.jpg (JPEG Image, 490x442 pixels) (RScott) ________________________________ Message 1 _____________________________________ Time: 06:37:58 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Engine mount as starter ground path At 11:35 PM 5/26/2009, you wrote: > > >t 08:47 PM 5/26/2009, you wrote: > > >The Z-14 I've put into my RV10 follows the best practices as >described in the Connection with one oversight.... I have the 2 >sided forest of tabs on the firewall but I only have an AWG 8 >cable running to it from the rear batteries instead of an AWG2 fat >wire. And it's too late to swap it out without significant re-work. Bill, re-reading my posting from last night I'm not sure I conveyed a clear image of my recommendations. In a nutshell: Add local grounds to airframe for the batteries if you don't already have them. Add crankcase to firewall ground stud for engine. Leave jumpers across the engine mount biscuits. You can cut the 8AWG wire out if you wish and if it is practical. It adds only weight and offers no significant electrical function. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 2 _____________________________________ Time: 06:37:59 AM PST US Subject: AeroElectric-List: KX-125 Installation Manual? From: "jf3sb" Ladies/Gents: I'm in the process of wiring up a KX-125 Nav/Com into my Zenith 701 panel. Would anyone happen to have an installation manual for this radio? I've got the connector pinouts, but still more questions than answers about what gets connected where. Thanks... John Flavin Olathe, KS Zenith CH701 still 80% and holding... Read this topic online here: http://forums.matronics.com/viewtopic.php?p=245534#245534 ________________________________ Message 3 _____________________________________ Time: 07:15:45 AM PST US From: "Johnson, Phillip (EXP)" Subject: AeroElectric-List: RE: AeroElectric-List Digest: 21 Msgs - 05/26/09 Bob, I read your message and went to your web link indicated below and I can't accept that it is a good design. The problem that I see is that your design does not create a single ground reference. Ideally you want the engine block to be the ground reference with all currents flowing through it. To this end you need to connect the battery -ve to the crankcase and then make all grounds connect, either directly or indirectly, to the crankcase as well. In doing this there will be no ground potential differences to upset the instrumentation. If we look at schematic given in http://www.aeroelectric.com/articles/grnding.pdf there is no alternator shown but we all know that the alternator ground is connected to the crankcase so all the current that the alternator generates must pass through the engine block and then on to the battery through the interconnections given in your circuit. If I now connect an instrument such as an engine monitor to the instrument panel and ground it as indicated in the diagram the ground voltage that the engine monitor uses will be different to the ground reference seen by the sensor located on the engine in particular when high currents are being sourced from the alternator. Such a configuration will cause erroneous readings unless a differential arrangement is utilised. In addition to the grounding issues related to the instrumentation it is likely that, at some point, someone will make some ground connections to the engine block and some to the instrumentation ground. Somewhere , we are all human, the two will interconnect (yes you could/should check for all of these but people don't in particular when the owner is not the builder). All will be well when the system is new but as the aircraft ages and maybe the aircraft is sold to a new owner the ground between the engine and instrumentation/firewall ground will be left off (maybe after an annual inspection or maintenance session) or degraded through loose connection. The pilot now tries to start the engine and all of the current tries to flow through this instrumentation ground. This causes a melt down of the wiring and a potential ground fire and risk to those expensive electronics. It is my opinion, and I believe that the automotive industry also adopts this philosophy, that you connect the battery ground to the crankcase and then strap the engine to the airframe/car body and system ground so that the high current grounds pass only through the engine. Charging ground currents, which can be extremely high, also only pass through the engine block thereby preventing erroneous instrumentation and potential fire risk. OK I've now started to run and get my flame suit on. Regards to all Phillip Johnson ________________________________ Message 7 _____________________________________ Time: 01:56:29 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Engine mount as starter ground path At 10:14 AM 5/26/2009, you wrote: > >Does anyone have some scientific information (beyond the practical >description in the Connection) that I can use to convince someone that >running the engine ground strap to the engine mount is a poor choice ? > >Thanks ! The shortest, lowest resistance and minimum parts count path in any high current conduction path is the road to Ground System Nirvana. See: http://www.aeroelectric.com/articles/grnding.pdf Engine mounts are steel assembled with steel hardware. The joints between mounts and other components of the airframe are not treated for the purpose of electrical "bonding". The engine mount is intended to hold the engine on the airplane and was not designed or installed to be a part of the electrical system. Note that Figure Z-15 and Chapter 5 of the 'Connection speak to and illustrate a notion that engines are best tied to the single point fire-wall ground block with a single-flexible- fatwire. To avoid having the firewall sheet participate in a PARALLEL ground path (read ground loop) any bonding jumpers across the engine mounts are best removed. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 4 _____________________________________ Time: 07:21:18 AM PST US From: DCS317@aol.com Subject: AeroElectric-List: SEC-1223 Power Supply --Question re isolating diode and charge limiting resistor Bob, On reading a recent thread on Aerolectrics, I ordered the SEC-1223 Power Supply from Universal Radio to power my avionics on the ground with direct connection to my aircraft battery as a battery backup. Question: The supplied manual gives a warning: "These units are power supplies and not battery chargers. Do not connect these units directly to a battery. Battery charging and battery charging may be undertaken only when the battery is connected through suitable external isolating diodes and charge limiting resistor. The isolating diode will ensure that the battery does not back power the power supply.. When the battery is deeply discharged, it will initially draw a very large charging current and thus, will force the power supply into current limit mode for prolonged periods. This is harmful for the power supply. The charge limiting resistor will limit the charging current, thereby, ensuring that the maximum charging current is well below the current limit value of the power supply. It is recommended that optional battery backup module BBM-1225 may be used to convert SEC-1223 for battery backup application." Looks simple enough to make my own module? Could you recommend a circuit with diagram and give your two cents regarding the warning? Don Schmiesing **************Dinner Made Easy Newsletter - Simple Meal Ideas for Your Family. Sign Up Now! 3Fhttp:%2F%2Frecipes.dinnermadeeasy.com%2F%3FESRC%3D622) ________________________________ Message 5 _____________________________________ Time: 07:46:52 AM PST US From: Werner Schneider Subject: Re: AeroElectric-List: KX-125 Installation Manual? Sent by PM br Werner jf3sb wrote: > > Ladies/Gents: > > I'm in the process of wiring up a KX-125 Nav/Com into my Zenith 701 panel. Would anyone happen to have an installation manual for this radio? I've got the connector pinouts, but still more questions than answers about what gets connected where. > > Thanks... > > John Flavin > Olathe, KS > Zenith CH701 still 80% and holding... > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=245534#245534 > > > ________________________________ Message 6 _____________________________________ Time: 09:21:48 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Grounding philosophy At 09:05 AM 5/27/2009, you wrote: Bob, I read your message and went to your web link indicated below and I can't accept that it is a good design. The problem that I see is that your design does not create a single ground reference. Yes it does. The architectures discussed in Figure Z-15 and other writings suggeste the stud at the forest of tabs on the firewall is the central point ground for the aircraft. Ideally you want the engine block to be the ground reference with all currents flowing through it. To this end you need to connect the battery -ve to the crankcase and then make all grounds connect, either directly or indirectly, to the crankcase as well. In doing this there will be no ground potential differences to upset the instrumentation. Instrumentation is a special case where grounded automotive sensors are at risk for suffering ground loop interference. This has been discussed at length in various writings. If the problem presents itself (usually manifest by a shift in instrumentation readings in response to alternator loads), then the "ground" leads for panel mounted instruments need to be extended to the crankcase. However, if one has a very low resistance net between he crankcase and the firewall ground stud . . . then the "problem" may be reduced to insignificant if not completely unobservable. The pilot now tries to start the engine and all of the current tries to flow through this instrumentation ground. This causes a melt down of the wiring and a potential ground fire and risk to those expensive electronics. Again, discussed in past publications and postings . . . "Smoking ground returns" is easily avoided by not closing the returns. Common occurrences include the risk of instrumentation grounds for instruments not designed to live in the real world of aircraft. Another common risk happens when builders attached p-lead shields to crankcase at one end and airframe at the other end. All of my drawings illustrate technique for avoiding that loop as well. It is my opinion, and I believe that the automotive industry also adopts this philosophy, that you connect the battery ground to the crankcase and then strap the engine to the airframe/car body and system ground so that the high current grounds pass only through the engine. Charging ground currents, which can be extremely high, also only pass through the engine block thereby preventing erroneous instrumentation and potential fire risk. Batteries go to crankcases in cars because the battery always sits right next to the engine. The automotive industry has adopted the same philosophy as every other industry for minimizing the numbers of joints, fasteners and pieces of wire in the fat-wire conduction paths. Now, if one had a battery on the forward side of the firewall then there is no electrical reason NOT to ground the battery right to the crankcase. There are mechanical reasons not to . . . we've already established the value of a 2AWG equivalent jumper from crankcase to ground stud. This same stud becomes a practical spot to ground a battery as well . . . and the 2AWG bonding strap makes sure that voltage differences between the crankcase and the ground stud are insignificantly small. If the battery is aft of the firewall, then the most practical battery ground is the firewall ground stud . . . or to the airframe on an all metal airplane. OK I've now started to run and get my flame suit on. Zero risk from me sir . . . Bob . . . ________________________________ Message 7 _____________________________________ Time: 09:29:31 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: SEC-1223 Power Supply At 09:18 AM 5/27/2009, you wrote: Bob, On reading a recent thread on Aerolectrics, I ordered the SEC-1223 Power Supply from Universal Radio to power my avionics on the ground with direct connection to my aircraft battery as a battery backup. Question: The supplied manual gives a warning: "These units are power supplies and not battery chargers. Do not connect these units directly to a battery. Battery charging and battery charging may be undertaken only when the battery is connected through suitable external isolating diodes and charge limiting resistor. The isolating diode will ensure that the battery does not back power the power supply.. When the battery is deeply discharged, it will initially draw a very large charging current and thus, will force the power supply into current limit mode for prolonged periods. This is harmful for the power supply. The charge limiting resistor will limit the charging current, thereby, ensuring that the maximum charging current is well below the current limit value of the power supply. It is recommended that optional battery backup module BBM-1225 may be used to convert SEC-1223 for battery backup application." Looks simple enough to make my own module? Could you recommend a circuit with diagram and give your two cents regarding the warning? Yes. I have a drawing in the pile of things to do that shows how to convert the SEC-1223 (or a similar power supply) to an "alternator emulator". The warnings from Samlex about using the stand-alone power supply as a battery charger are well taken. Any time I've used these supplies to power up the airplane in the shop, the power supply was used as a battery emulator. I'll see if I can dig out those drawings and publish them along with the explanatory text. In the mean time, just use the power supply to energize the system (tied to the alternator b-lead?) but leaving the battery master switch OFF. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 8 _____________________________________ Time: 10:03:13 AM PST US Subject: Re: AeroElectric-List: Grounding philosophy From: "Matt Prather" > > snip > > Batteries go to crankcases in cars because the battery > always sits right next to the engine. The automotive > industry has adopted the same philosophy as every other snip Just to be contrarian, our family has owned two different cars with the battery in the trunk (rear) and the engine in the front - both foreign jobs.. :) The manufacturer claims they did it for better weight distribution. I can't recall whether the batteries were locally grounded, or if they had a dedicated ground wire running to the front. > > Bob . . . > Matt- ________________________________ Message 9 _____________________________________ Time: 11:03:47 AM PST US From: Lincoln Keill Subject: AeroElectric-List: Re: Engine mount as starter ground path The discussion about engine mounts as ground points has generated a questio n. -The "When is a Good Ground Not?" article shows 2AWG wire for the high current paths as do the Z-15 diagrams demonstrating various grounding arch itectures. - The Z-13/8 diagram I was planning my electrical system around shows 4AWG wi res for these same high current paths. -All my "fat wires" will be under 3 feet since my RG battery, starter and battery contactors, 40A alternator, and firewall ground block will all be on or close to the firewall. -I th ought I had read somewhere in the "AeroElectric Connection" that 4AWG was f ine as long as all the fat wires were 3 feet or less, but now I can't find it. Could someone confirm that 4AWG welding cable is acceptable for the high cu rrent wires when these wires are all located on the hot side of the firewal l, wired per Z-13/8 and each under three feet in length? Lincoln KeillRV-7A Do not archive ________________________________ Message 10 ____________________________________ Time: 11:13:38 AM PST US From: Bill Mauledriver Watson Subject: Re: AeroElectric-List: Engine mount as starter ground path It's crystal clear now! Thanks Robert L. Nuckolls, III wrote: > > > At 11:35 PM 5/26/2009, you wrote: >> >> >> t 08:47 PM 5/26/2009, you wrote: >> >> >> The Z-14 I've put into my RV10 follows the best practices as >> described in the Connection with one oversight.... I have the 2 sided >> forest of tabs on the firewall but I only have an AWG 8 cable >> running to it from the rear batteries instead of an AWG2 fat wire. >> And it's too late to swap it out without significant re-work. > > Bill, re-reading my posting from last night I'm not > sure I conveyed a clear image of my recommendations. > In a nutshell: > > Add local grounds to airframe for the batteries if > you don't already have them. > > Add crankcase to firewall ground stud for engine. > > Leave jumpers across the engine mount biscuits. > > You can cut the 8AWG wire out if you wish and > if it is practical. It adds only weight and > offers no significant electrical function. > > > Bob . . . > > ----------------------------------------) > ( . . . a long habit of not thinking ) > ( a thing wrong, gives it a superficial ) > ( appearance of being right . . . ) > ( ) > ( -Thomas Paine 1776- ) > ---------------------------------------- > > ________________________________ Message 11 ____________________________________ Time: 12:11:36 PM PST US From: "Bill Bradburry" Subject: AeroElectric-List: DynaFocal engine mount ring Not exactly electric, but airplane related... I have an engine mount ring for sale.. I am using an alternative engine, so I don't need this ring. AC Spruce sells it for $180 plus shipping. I will sell mine for $125 plus shipping. It is a Type 1 Dynafocal with 2.75 cups. Bill B ________________________________ Message 12 ____________________________________ Time: 12:25:16 PM PST US From: "David LLoyd" Subject: Re: AeroElectric-List: Engine mount as starter ground path Static is usually described as high voltage and little to no current. That means those nasty electrons are really juiced up...like a 2 year old loaded with chocolate cake, etc. They can jump tall buildings, and wide gaps, etc. A hopped up electron does not need a good conductor to move and be a nuisance. Rusty or otherwise not well connected pipes, etc. work just fine. So connecting a static grounding line to an exhaust pipe should work just fine to dump most, if not all, of the electrons to ground. Most of my Cessna wing is bare aluminum. As an extra precaution, I lightly touch the fuel nozzle to the wing surface before I even take the fuel caps off. That also relieves any final electrons off the table before fueling. Also, as the fuel flows, I make sure the nozzle is touching the metal filler neck. In dry climates especially, flowing fuel will also generate some static. With the nozzle grounded against the filler metal that takes care of those speedy critters also. David ----- Original Message ----- From: Kelly McMullen To: aeroelectric-list@matronics.com Sent: Tuesday, May 26, 2009 2:21 PM Subject: Re: AeroElectric-List: Engine mount as starter ground path Given such a ground path, how does one get lineboys trained that the engine exhaust pipe is a terrible place for ground wire, that the fuel tanks are in the wings, and something like a bare spot on wing tiedown has a much shorter ground path? I always wonder how static charge is supposed to make it from the fuel tank through the airframe to the engine and down the rusty, carboned up exhaust pipe, usually with a swivel or slip joint or two to that ground wire, without significant resistance. Robert L. Nuckolls, III wrote: At 10:14 AM 5/26/2009, you wrote: Does anyone have some scientific information (beyond the practical description in the Connection) that I can use to convince someone that running the engine ground strap to the engine mount is a poor choice ? Thanks ! The shortest, lowest resistance and minimum parts count path in any high current conduction path is the road to Ground System Nirvana. See: http://www.aeroelectric.com/articles/grnding.pdf Engine mounts are steel assembled with steel hardware. The joints between mounts and other components of the airframe are not treated for the purpose of electrical "bonding". The engine mount is intended to hold the engine on the airplane and was not designed or installed to be a part of the electrical system. Note that Figure Z-15 and Chapter 5 of the 'Connection speak to and illustrate a notion that engines are best tied to the single point fire-wall ground block with a single-flexible- fatwire. To avoid having the firewall sheet participate in a PARALLEL ground path (read ground loop) any bonding jumpers across the engine mounts are best removed. Bob . . . ________________________________ Message 13 ____________________________________ Time: 01:06:26 PM PST US From: "Wade Roe" Subject: AeroElectric-List: Alternator with built-in regulator I am building an RV-7 and have purchased a stock alternator from Vans (in firewall forward kit). I understand this unit to have a built-in regulator. I hope to use the B&C LR3C-14. Being new to aircraft electronics...will this create an issue or is there something that I'm missing? Wade Roe SOUTHERN CARBIDE TECHNOLOGIES, INC. 7739 Unity Road M&D Industrial Park Tuscaloosa, AL 35401 205-248-6700 205-248-6372 fax ________________________________ Message 14 ____________________________________ Time: 01:43:21 PM PST US From: "Hinde, Frank George (Corvallis)" Subject: RE: AeroElectric-List: Alternator with built-in regulator If the regulator is built in it means exactly that..No external regulator will be required or indeed desired... Did you get the Plane Power 60A alternator or the rebuilt Honda unit I think it is. The Plane Power is the finest internally regulated alternator there is and Van's has the best prices on them. If you are building an electrically dependant airplane or an IFR bird then this is the unit you should have. Frank -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Wade Roe Sent: Wednesday, May 27, 2009 1:00 PM Subject: AeroElectric-List: Alternator with built-in regulator I am building an RV-7 and have purchased a stock alternator from Vans (in firewall forward kit). I understand this unit to have a built-in regulator. I hope to use the B&C LR3C-14. Being new to aircraft electronics...will this create an issue or is there something that I'm missing? Wade Roe SOUTHERN CARBIDE TECHNOLOGIES, INC. 7739 Unity Road M&D Industrial Park Tuscaloosa, AL 35401 205-248-6700 205-248-6372 fax ________________________________ Message 15 ____________________________________ Time: 02:23:43 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: State of the art - then and now I'm in possession of several issues of the Electrical Experimenter circa 1916. This hobbyist/amateur/semi- professional publication offered a newsstand source for both understanding and state of the art news in a range of technologies. I'm using one of these magazines as reference for a science history presentation I'm doing. I've scanned it for sharing and thought I would post it for those having an interest in such things. See: http://tinyurl.com/ofbj3c It's interesting to see the depth and scope of interests illustrated on these pages. It's also interesting to see a level of hucksterism and quackery not unlike that which pours forth in today's video and print media! See pdf pages 7, 25, 62 (violet rays), 65 (Pandiculator). But the casually discriminating eye can easily identify and appreciate the good stuff of which there is plenty. Hope you enjoy browsing this piece of technological history. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 16 ____________________________________ Time: 02:23:48 PM PST US From: "Wade Roe" Subject: RE: AeroElectric-List: Alternator with built-in regulator The alternator from Vans is a reconditioned Japanese automobile unit (Honda?) that came with the firewall forward kit. I figured the B&C linear regulator to be a superior/cleaner product than that on the alternator. The plane will be IFR and all electric. Wade Roe -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Hinde, Frank George (Corvallis) Sent: Wednesday, May 27, 2009 3:37 PM Subject: RE: AeroElectric-List: Alternator with built-in regulator (Corvallis)" If the regulator is built in it means exactly that..No external regulator will be required or indeed desired... Did you get the Plane Power 60A alternator or the rebuilt Honda unit I think it is. The Plane Power is the finest internally regulated alternator there is and Van's has the best prices on them. If you are building an electrically dependant airplane or an IFR bird then this is the unit you should have. Frank -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Wade Roe Sent: Wednesday, May 27, 2009 1:00 PM Subject: AeroElectric-List: Alternator with built-in regulator I am building an RV-7 and have purchased a stock alternator from Vans (in firewall forward kit). I understand this unit to have a built-in regulator. I hope to use the B&C LR3C-14. Being new to aircraft electronics...will this create an issue or is there something that I'm missing? Wade Roe SOUTHERN CARBIDE TECHNOLOGIES, INC. 7739 Unity Road M&D Industrial Park Tuscaloosa, AL 35401 205-248-6700 205-248-6372 fax ________________________________ Message 17 ____________________________________ Time: 02:30:51 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Alternator with built-in regulator At 02:59 PM 5/27/2009, you wrote: > >I am building an RV-7 and have purchased a stock alternator from Vans >(in firewall forward kit). I understand this unit to have a built-in >regulator. I hope to use the B&C LR3C-14. Being new to aircraft >electronics...will this create an issue or is there something that I'm >missing? Do you have a copy of the 'Connection? It speaks to the various configurations for internally/externally regulated alternators. The updated chapter on alternators is posted at: http://aeroelectric.com/R12A/03_Alternator_12A1.pdf Most single engine airplanes fly with externally regulated alternators for reasons offered in the chapter cited above. But either configuration can be adapted to aircraft. If you have a Plane Power unit from Van's, know that it has been successfully integrated into aircraft while meeting design goals for ON/OFF, any time, any conditions control. Further, it's fitted with over-voltage management. You won't need an LR-3 for this alternator. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 18 ____________________________________ Time: 02:37:45 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Engine mount as starter ground path At 01:00 PM 5/27/2009, you wrote: >The discussion about engine mounts as ground points has generated a >question. The "When is a Good Ground Not?" article shows 2AWG wire >for the high current paths as do the Z-15 diagrams demonstrating >various grounding architectures. > >The Z-13/8 diagram I was planning my electrical system around shows >4AWG wires for these same high current paths. All my "fat wires" >will be under 3 feet since my RG battery, starter and battery >contactors, 40A alternator, and firewall ground block will all be on >or close to the firewall. I thought I had read somewhere in the >"AeroElectric Connection" that 4AWG was fine as long as all the fat >wires were 3 feet or less, but now I can't find it. > >Could someone confirm that 4AWG welding cable is acceptable for the >high current wires when these wires are all located on the hot side >of the firewall, wired per Z-13/8 and each under three feet in length? The drawings published on our website and publications are intended to illustrate architectures. Exact sizing of circuit protection, wires, batteries, alternators, etc. are up to the builder based on a host of considerations. Your recollection is accurate in that if the battery, starter and alternator are all within short distances of each other (3' or so) then 4AWG is adequate to the task of managing fat-wire duties. When engine and batteries are remotely located from each other (rear mounted batteries in RV-8, canard pushers) will benefit from something bigger like 2AWG battery cables. Really extreme cases like some some winged watercraft, parallel 2AWG or 0AWG is often used. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 19 ____________________________________ Time: 02:52:45 PM PST US From: "Hinde, Frank George (Corvallis)" Subject: RE: AeroElectric-List: Alternator with built-in regulator In that case send that alternator back to Vans and exchange it for the plane power unit...Trying to use the B&C regulator (which it was not designed for) is a bit like putting lipstick on a pig..Its still a pig! I futzed with a rebuilt alternator for a while and had a couple of scary moments in IMC..then I changed to the Plane power and its been faultless ever since. They come with a wonderful reputation. No electrical noise, just fit (with the supplied brackets) and forget it. On An all electric IFR airplane the alternator is not the place to be making shortcuts!!!..The extra couple of hundred bucks is WELL spent. Frank RV7a..all electric IFR including 2* EI's and the fuel pumps! -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Wade Roe Sent: Wednesday, May 27, 2009 2:20 PM Subject: RE: AeroElectric-List: Alternator with built-in regulator The alternator from Vans is a reconditioned Japanese automobile unit (Honda?) that came with the firewall forward kit. I figured the B&C linear regulator to be a superior/cleaner product than that on the alternator. The plane will be IFR and all electric. Wade Roe ________________________________ Message 20 ____________________________________ Time: 08:40:17 PM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Alternator with built-in regulator > > >The plane will be IFR and all electric. > >Wade Roe > Wade, would it be a fair assumption then that a second alternator will go onto the vacuum pump pad? Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 21 ____________________________________ Time: 08:41:35 PM PST US From: RScott Subject: AeroElectric-List: Military_Humor_Miss_America_1.jpg (JPEG Image, 490x442 pixels) http://www.allmilitary.com/i/Image/Military_Humor_Miss_America_1.jpg ------------------------------------------------------------------------------------- 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.