---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Fri 06/17/05: 3 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 08:09 AM - Re: Re: 40amp Denso Aerosport Alternator (Robert L. Nuckolls, III) 2. 10:23 AM - Boost Pump Wiring (John Schroeder) 3. 06:49 PM - KT-76 Solder connector (Bill Judge) ________________________________ Message 1 _____________________________________ Time: 08:09:44 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: 40amp Denso Aerosport Alternator --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 09:35 PM 6/13/2005 -0700, you wrote: >--> AeroElectric-List message posted by: > > > >Bob N wrote: > >Okay, it's your considered recommendation that if one > >purchases p/n (xxxxx) from supplier (YYYYY) then OV > >protection is not called for. You've cited data to support > >your advice. Now, how do we get this information into > >the hands of the greatest numbers of builders? > > >Bob, my advice is from a ranked amateur and offer it with no warrantee. >You have served to improve the knowledge and best interested of count less >builders, including myself. I dont think we need to disseminate my opinion >further than this list. > > > >George, you seem to have completely missed the point > >I've been trying to illustrate during this endless > >thread. YOU and many like you are building ONE airplane. > >You may have conversed with others to gather data > >on and make selection of specific components in > >which you have either trust supported by repeatable > >experiments or faith supported by the gross weight of > >anecdotal information. In either case, you're certainly > >free to go forward with your choice and I wish you well. > > >There are no one-size fits all solutions. I have not listed any specific >part numbers because frankly I dont want the liability. Second I have been >honest that getting detailed info on a Denso alternator and design in next >to impossible since all the engineers are in Japan. As far as anecdotal >evidence, I have tracked down as much info on how transistors fail, why >and what characteristics different transistors have. It is not a fact but >a widely held electronics industry expectation that transistor are VERY >reliable. The external V-regulator and crow bar is no doubt more bullet >proof. I take your word on it based on your experience and it makes >sense. I think for most builders they take things on faith and standard >practice. No need to reinvent the wheel. > > >I think the hey my Denso has worked for 10 years with no problems is just >that, anecdotal. I agree. As far as tests, sadly are in Japan and in >Japanese. I hear the Japanese are good with electronics. I am sure Denso >with 20-30 years making alternators with internal VRs have tested them and >done failure analysis. Granted a car is not an airplane and I have no proof. > > > >Please understand that I write for thousands of builders > >working on thousands of airplanes being fabricated all > >over the world. Their choices for selection of a suitable > >alternator MIGHT include part number (xxxxx) and maybe > >they have access to supplier (YYYYY) but I would be > >remiss in my duties if I were to LIMIT my recommendations > >to this narrow range of choices . . . especially when > >I have no data from any repeatable experiments > >to support my advice. Further, there are MILLIONS of > >alternators with THOUSANDS of part numbers that will > >perform very well and free of concerns if we drive > >probability of hazardous failure down with layered > >systems architecture . . . this is a major component > >of FAILURE TOLERANT design. You ASSUME that a part > >will fail and then incorporate protection -OR- > >alternate technology (Plan B). > > >Bob, I understand all your recommendations. I understand from your >analysis, lack of information and judgment you cant endorse it. I think >your opinions are the most conservative and will provide a method of DC >power production in an aircraft that provides repeatable reliability and >a level of safety required in certified aircraft designs. However for me >in a VFR RV (experimental) with an engine that does not require electrical >power (mechanical systems and self sustaining ignition), I can get away >with an alternate path to electric DC power generation. This path is using >an internal VR alternator with no extra external OV protection. I have OV >warning (large flashing red light) and a manual way to disconnect the >alternator output (b-lead) from the system thru a CB. Works for me and me >only. > > >Others have used the Denso 40 amp, aka Niagara, with good results. Again >far from rigorous scientific proof, but a collection of general facts, >anecdotes and opinion. My recommendation is inferior to the method of >using an external alternator regulator and an OV module, aka crow-bar, in >a rigorous scientific way. However my design will work OK as intended and >be safe in my opinion, while being lighter, simpler, and cheaper. > > > >When I handed control lock keys of an explosively > >launched recovery parachute controller to the pilot who > >was going to depend on that system to safe his life > >and perhaps his airplane, I could look him right in > >the eye and offer that I have done the best I know > >how to do. When I write words on this List and for > >the 'Connection, I believe am operating with that > >same sense of duty to offer the best and most > >universally useable information available. I am > >pleased that you have discovered what you believe > >is the ultimate solution to your system design > >goals and parts procurement issues. Please fly them in > >good health. The odds are definitely in your favor. > > >Mr. Nuckolls not to pander to you in anyway, sincerely you have single >handedly educated thousands of pilot/builders about electrical systems. >The knowledge of the aviation community in general is the better for your >contributions. The average aircraft (homebuilt) electrical system has >improved due to your efforts. I dont mean to undermine your methods, >analysis or opinions. However I do pick a choose what features I install >in my electrical system. The most notably is the internal regulated >alternator. I think you have said this yourself, If it can fail assume it >will and what will happen when it does. I have analyzed my system and find >that all alternator failures will be passive and not a threat to safety of >flight FOR ME. (Dont try this at home, your mileage may vary and this info >is provided for entertainment purposes only, Sincerely Georges Lawyers, >Dwey-Cheat'em and Howe) > > > >But understand that I've obligated myself to operate > >in a wider arena and to offer advice that permits > >me to look any builder in the eye and offer that > >it's the best and most universally applicable > >technology I know how to do right now. I have no > >FAITH in the universal performance of all the > >automotive alternators available to the OBAM aircraft > >community around the world but I do have the > >knowledge of countless REPEATABLE EXPERIMENTS > >conducted to craft the most failure tolerant > >and hazard free systems I know how to do today. > > >Amen, I have no way, other than FAITH, that the Denso alternator will not >hurt me or the airframe, and the level of risk, is appropriate and I am >willing to accept it and understand it. I have determined that my old >Collins transponder and new Icom A200 (without OV protected power supply) >may likely be damaged. Other equipment is OV protected internally and if >damaged the manufacture assured me the damage would be repairable at >nominal cost. Plan A never have an electrical failure. My maintenance plan >to assure reliability is checking electrical volts and amps carefully for >any sign/trend of impending failure, replace battery on regular basis and >never over load alternator. During flight test I will thermocouple >alternator to determine operating temps are acceptable. Blast cooling tube >will be installed. > > > > I'm not here to argue against the gospel of > >Nipon Denso or any other. I have tools called > >Failure Mode Effects Analysis, decades of experience > >with others who design, build and fly airplanes > >and a personal goal of understanding how things > >work and sharing that with anyone who has an > >interest. I cannot advise a builder to adopt a > >design philosophy that I do not understand or that > >he cannot understand AND CONTROL. > > >Bob, no one mounting the sermon; You are right you dont have ABSOLUTE >control and dont have complete understanding how the IC chip and >transistor works in a Denso. I have gone as far as I needed to see the >truth, GOOD ENOUGH for me, no more or less. I really think alternators >with internal regulators are getting better and soon will have failsafe >internal regulators. The auto industry will demand it and we will benefit >from it. > > >Other alternators like Mitsubishi have also worked well, and from my >research others like Delco/Motorola/Hitachi have had poor service history >according to the Highway Safety foundation. The Denso has just happened to >become the De-facto choice for homebuilders, proven to be reliable in >cars, industrial equip and planes, size, weight and the dual internal fans. > > >I looked at the problem of over voltage, load dump, transient voltage and >equipment protection and found that it is acceptable that my system suffer >an OV condition, so reliably is moot. However I prey that it will be as >reliable as I think it will be and as others have experienced. The chance >of fire or catastrophic failure of the alternator is nill. I do run the >risk of some equipment damage if a rare OV occurred, but that may be >limited to a few hundred dollars of damage. That is where I am putting my >faith, but this is a special system design and meets my fault tolerance >analysis. > > >If it can fail it will and any failure should not cause a hazard. Amen, we >shall now turn our Aeroelectric Hymnal to page XX. > > > >Bob . . . > > >All the best and I thank you again for forcing us to critically think thru >out systems. Even if it is not the perfect solution for ALL at least it is >MY system and I have knowledge of the risk and benefits. I am searching >for the lightest and most reliable electrical system I can get, and I >accept the risk of an OV as unlikely but an acceptable one. Bob I have >learned a lot from your books and forum. Carefully considered and well put sir . . . with one minor exception. I hope I'm not "forcing" anyone to do anything, even if it's to exercise the benefits of critical thinking. I appreciate your participation here on the List. The quality of our critical thinking can only grow when we have multiple gray matter masses considering the questions! Bob . . . ________________________________ Message 2 _____________________________________ Time: 10:23:19 AM PST US Subject: AeroElectric-List: Boost Pump Wiring From: "John Schroeder" --> AeroElectric-List message posted by: "John Schroeder" Hello Bob - Attached is a wire sheet showing the wiring for a Dukes Fuel pump that we installed in our Lancair ES. For some reason, Dukes keeps voltage on the lead that is not in use - as designated by the switch position. We discovered this when we turned the pump on for a quick check and both annunciator lights lit up. We tested a solution of inserting diodes in line on each power lead to the pump. This works great. We used the 1n5400 diodes, but I wonder if the 3 amp capacity is sufficient. Dukes recommends a 7.5 amp fuse for the device. Any comments on: (1) The wiring itself? (2) The size of the diodes? Many thanks, John Schroeder -- ________________________________ Message 3 _____________________________________ Time: 06:49:53 PM PST US From: Bill Judge Subject: AeroElectric-List: KT-76 Solder connector --> AeroElectric-List message posted by: Bill Judge Hello All: I'm installing a KT-76 in my RV-8 and would like to be able to easily disconnect the transponder from the co-ax but it has a solder termination rather than a BNC. Does anyone know if there is BNC version of this connector? If not then I'll put a connector down the line a few inches but that would be adding more places for failure... Thanks in advance. Bill Judge N84WJ