---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 07/08/10: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:37 AM - Re: Re: Heat Sink necessary? (Ken) 2. 06:59 AM - Re: Re: Lithium Battery Option () 3. 07:38 AM - Re: Heat Sink necessary? (jonlaury) 4. 01:46 PM - Re: Re: Heat Sink necessary? (Ken) 5. 02:09 PM - Quick splice connectors? (Jack L Bell) 6. 02:37 PM - Re: Quick splice connectors? (Robert L. Nuckolls, III) 7. 03:23 PM - Re: Quick splice connectors? (Bob McCallum) 8. 04:31 PM - Re: Quick splice connectors? (Mike Welch) 9. 05:23 PM - Re: Quick splice connectors? (Jack L Bell) 10. 05:39 PM - Re: Quick splice connectors? (sharmon32) ________________________________ Message 1 _____________________________________ Time: 04:37:54 AM PST US From: Ken Subject: Re: AeroElectric-List: Re: Heat Sink necessary? Normally injectors are sized such that full on only represents about 30% extra fuel over full power. (sized primarily to give better idle control) So yes in most cases an engine will run at aircraft cruise power or higher with all injectors locked full on. I would consider one or more locked on injectors a single failure. Older ecu's batch fire injectors and share drivers. But yes you'd need to go into ecu and wiring specifics to determine whether a single failure could lock more than one injector on. 100% extra fuel (twice normal flow) on my subaru makes the exhaust system quite hot but does not stop the engine. Rare but injectors do occasionally fail on. A minor concern admittedly. Similarly for multiple coil ignitions. Rare but I've seen single coils short out internally and draw continuous current. I'm just suggesting that some headroom or safety margin in the sizing and fusing of such circuits is a good idea and that would include any diodes. Ken Robert L. Nuckolls, III wrote: > > > At 05:47 PM 7/7/2010, you wrote: >> >> It is sometimes good to imagine what can go wrong. Generally high >> impedance injectors run around 12 ohms resistance. If one or more >> injector driver fails on, the engine will likely keep running unless >> subsequently a fuse pops or a diode fails due to the extra current. >> I'd consider making sure the diode had some heat sinking and was >> capable of feeding all six injectors at 100% duty cycle which is >> likely 7+ amps at 14+ volts. > > Would that not be a multiple failure scenario? . . . > and would the engine run with 5 of the 6 injectors > turned on hard? > > Bob . . . > ________________________________ Message 2 _____________________________________ Time: 06:59:52 AM PST US Subject: RE: AeroElectric-List: Re: Lithium Battery Option From: I love it - Porsche throws in a lead acid battery just in case it gets a bit chilly for the lithium. At 13 pounds it's not a huge savings on the RG jobs. Glenn -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Jon Finley Sent: Wednesday, July 07, 2010 6:28 PM Subject: RE: AeroElectric-List: Re: Lithium Battery Option If my math is right, that works out to $77.00/pound. Not quite up to the rumored $100,000/pound that Formula 1 is willing to pay but still out of my budget.... :-( Jon -----Original Message----- From: "N38CW" Sent: Wednesday, July 7, 2010 3:47pm Subject: AeroElectric-List: Re: Lithium Battery Option Yep, it's a bit pricey... http://www.motorauthority.com/blog/1039902_porsches-1700-starter-battery-option-for-boxster-spyder-911-gt3 -------- Bill Settle RV-8 Fuselage Read this topic online here: http://forums.matronics.com/viewtopic.php?p======== ________________________________ Message 3 _____________________________________ Time: 07:38:27 AM PST US Subject: AeroElectric-List: Re: Heat Sink necessary? From: "jonlaury" Ken, Thank you for your illumination of some issues surrounding EFI. The Simple Digital Systems EFI is the one I'm using. Your comments have explained why SDS said that I might want to consider using a 15 amp circuit. It never made sense to me until I read your comments about sizing for all 6 injectors locking on (100% duty cycle). The bridge diode that I'm using is rated for 25a @ 200v so there seems to be sufficient headroom. My injectors are low impedance type and SDS supplies a 3 x 4 x 1/8" aluminum piece with 3 gold anodized resistors??(I'm guessing) that have fins radiating around them. Installation instructions say this piece can get "quite hot at higher duty cycles". It seems that the SDS EFI 'wants' to have high impedance injectors. Are there advantages to a high impedance architecture? John Read this topic online here: http://forums.matronics.com/viewtopic.php?p=304179#304179 ________________________________ Message 4 _____________________________________ Time: 01:46:55 PM PST US From: Ken Subject: Re: AeroElectric-List: Re: Heat Sink necessary? John Port injectors are usually high impedance and they are by far the most common injector. They simplify control issues and drive circuits and are the only ones that I've played with. Suitable mosfet (transistor) switches are very cheap and don't have large heat sinking requirements. I allow just over 1 millisec opening delay for mine when calculating and the 90 volt spike when I turn them off is not much of a problem. Large injectors for throttle body injection or very high power engines are more likely to be low impedance. Larger injectors need more energy to activate them. I have not used them but they are not uncommon in the aftermarket. Low impedance ones will open faster I believe but you typically throttle back the current to a hold open value. That likely extends life but it also lets them close faster. The higher current and higher voltage spikes of low impedance injectors complicates things. Your power resistors would be there to reduce the hold open current. There are other methods like pulse width modulation, flyback circuits, etc. There are hardware and software methods of accomplishing all this but it is simpler with the high impedance (lower current) injectors. I'm pleased if I helped a bit. SDS does good work and they likely have better explanations of this on their extensive website so definitely follow their recommendations. Ken jonlaury wrote: > > > Ken, Thank you for your illumination of some issues surrounding EFI. > The Simple Digital Systems EFI is the one I'm using. Your comments > have explained why SDS said that I might want to consider using a 15 > amp circuit. It never made sense to me until I read your comments > about sizing for all 6 injectors locking on (100% duty cycle). The > bridge diode that I'm using is rated for 25a @ 200v so there seems to > be sufficient headroom. My injectors are low impedance type and SDS > supplies a 3 x 4 x 1/8" aluminum piece with 3 gold anodized > resistors??(I'm guessing) that have fins radiating around them. > Installation instructions say this piece can get "quite hot at higher > duty cycles". It seems that the SDS EFI 'wants' to have high > impedance injectors. Are there advantages to a high impedance > architecture? > > John > ________________________________ Message 5 _____________________________________ Time: 02:09:05 PM PST US From: Jack L Bell Subject: AeroElectric-List: Quick splice connectors? I've begun wiring, and have always hated cutting a good wire to splice into it. I've found no reference to the quick splices in any of the aircraft parts catalogs, so before giving up, and cutting the ignition CDI wires to connect the kill switches (That alone feels all sorts of wrong to me..), I thought I'd ask the question: Has anyone used a splice such as http://www.wiringproducts.com/contents/en-us/d266.html in their wiring? Thanks, -Jack Austin, TX Avid Catalina (getting there..) ________________________________ Message 6 _____________________________________ Time: 02:37:59 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Quick splice connectors? >I thought I'd ask the question: Has anyone used a splice >such as http://www.wiringproducts.com/contents/en-us/d266.html >in their wiring? Keep in mind that the design goal for bringing two wires together is "gas tightness". I.e. give the joining the same environmental resistance to effects of moisture and oxygen as if they were one piece of metal. Detailed discussions of these goals and some of the recipes for achieving them are discussed at: http://aeroelectric.com/articles/rules/review.html http://aeroelectric.com/articles/Solder_Lap_Splicing/Solder_Lap_Splices.html http://aeroelectric.com/articles/terminal.pdf The splices you've cited are not crafted to these design goals. I've seen those used on aircraft that traveled to various air shows . . . but the question to be asked is not "have you used them?" but "what studies have shown them to be of the same caliber as legacy products and processes that have been proven to be essentially zero risk?" Bob . . . ________________________________ Message 7 _____________________________________ Time: 03:23:30 PM PST US From: "Bob McCallum" Subject: RE: AeroElectric-List: Quick splice connectors? Jack; Absolutely not! These were developed, I believe, as a "quick'n'dirty", temporary connection in the automotive industry for such applications as a one time trailer hook-up for say a rental trailer. Personal (bad) experience is that they are unreliable and in a very short time the nice one piece original wire will corrode through where this so called "splice" damaged the insulation. I wouldn't use them for anything let alone on an aircraft. They certainly don't provide the nice solid "gas tight" joint that the properly crimped PIDG terminals provide. Where and how would you propose to use such a connection? I don't follow the reference to having to cut the CDI wires. The power supply to a CDI ignition, I would have thought, would involve a supply wire and a ground wire just like any other accessory. No?? If they need to be "spliced" then a proper PIDG splice is the way to go. See http://tinyurl.com/2575j6g or http://tinyurl.com/27zackn Now all of this is my personal opinion and others may differ, but for what it may be worth, there you have it. Bob McC > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list- > server@matronics.com] On Behalf Of Jack L Bell > Sent: Thursday, July 08, 2010 5:08 PM > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: Quick splice connectors? > > > > > I've begun wiring, and have always hated cutting a good wire > to splice into it. I've found no reference to the quick > splices in any of the aircraft parts catalogs, so before > giving up, and cutting the ignition CDI wires to connect > the kill switches (That alone feels all sorts of wrong to me..), > I thought I'd ask the question: Has anyone used a splice > such as http://www.wiringproducts.com/contents/en-us/d266.html > in their wiring? > > Thanks, > > -Jack > Austin, TX > Avid Catalina (getting there..) > > _- > ==================================================== > ====== > _- > ==================================================== > ====== > _- > ==================================================== > ====== > _- > ==================================================== > ====== > > ________________________________ Message 8 _____________________________________ Time: 04:31:58 PM PST US From: Mike Welch Subject: RE: AeroElectric-List: Quick splice connectors? > Absolutely not! > > These were developed=2C I believe=2C as a "quick'n'dirty"=2C temporary co nnection > in the automotive industry for such applications as a one time trailer > hook-up for say a rental trailer. > Bob McC Jack=2C I was going to respond to your question regarding the splices you asked a bout=2C but then I read Bob McC's email. He said essentially the same thin g I was going top say. These splices are what the (U-Haul=2C Ryder=2C etc) trailer hook-up guys grab=2C to keep from doing a proper splicing job. Th ey're quick=2C they corrode=2C and they're virtually useless on anything of long term dependability. I've used them=2C but NEVER on an airplane. Basically=2C they're junk. My opinion.... Mike Welch _________________________________________________________________ Hotmail is redefining busy with tools for the New Busy. Get more from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID28326::T:WLMTAGL:O N:WL:en-US:WM_HMP:042010_2 ________________________________ Message 9 _____________________________________ Time: 05:23:39 PM PST US From: Jack L Bell Subject: AeroElectric-List: Re: Quick splice connectors? >Keep in mind that the design goal for bringing >two wires together is "gas tightness". I.e. >give the joining the same environmental resistance >to effects of moisture and oxygen as if they were one >piece of metal. Detailed discussions of these goals >and some of the recipes for achieving them are >discussed at: That whole concept of gas tightness is what led me down the path of those connectors: I figured leaving the wire intact in the first place was better than cutting, then rejoining the wire. I'd looked at the mechanical support from the better connectors, and didn't see any disadvantage there, but had not considered the galvanic reaction from dissimilar metals. That might be a problem in an amphibian. The entire plan was to follow the whole theory of the kill switch in the first place- if it fails, the engine keeps running. I'll go down a modified solder-lap approach. I'm *much* more comfortable with solder joints than crimp joints, and will support them with a double heat-shrink cover. (Lead exposure? What might a few years of soldering circuit boards by hand add in the way of exposure? I figure that's why I'm always on a diet..) Thanks again, Jack ________________________________ Message 10 ____________________________________ Time: 05:39:00 PM PST US From: "sharmon32" Subject: Re: AeroElectric-List: Quick splice connectors? Jack : They use those splices at the U-haul trailer place. They will screw up your trailer wiring in about one year they are junk. I would never put anything like that in my plane. I would trim the insulator back real careful and solder the wire you want to connect then use some of that plastic stuff coat in and cover it with shrink wrap. STeve Not a wiring expert Steven W. Harmon 2446 E. 3800 N. Filer Idaho 83328 "Lovin Life in Idaho" Where Being poor on a farm beats being rich in the city ----- Original Message ----- From: "Jack L Bell" Sent: Thursday, July 08, 2010 3:08 PM Subject: AeroElectric-List: Quick splice connectors? > > > > I've begun wiring, and have always hated cutting a good wire > to splice into it. I've found no reference to the quick > splices in any of the aircraft parts catalogs, so before > giving up, and cutting the ignition CDI wires to connect > the kill switches (That alone feels all sorts of wrong to me..), > I thought I'd ask the question: Has anyone used a splice > such as http://www.wiringproducts.com/contents/en-us/d266.html > in their wiring? > > Thanks, > > -Jack > Austin, TX > Avid Catalina (getting there..) > > > ------------------------------------------------------------------------------------- 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.