AeroElectric-List Digest Archive

Wed 12/03/14


Total Messages Posted: 15



Today's Message Index:
----------------------
 
     1. 07:14 AM - Touchy (Joe)
     2. 08:24 AM - Re: Touchy (rayj)
     3. 08:27 AM - Re: Fusible links (Robert L. Nuckolls, III)
     4. 09:16 AM - Toroid beads VOR antenna vs. Active VOR antenna (Robert L. Nuckolls, III)
     5. 09:17 AM - Re: Fusible links (Charlie England)
     6. 10:04 AM - =?utf-8?Q?Re:__Fusible_links? ()
     7. 11:20 AM - Re: Fusible links (Robert L. Nuckolls, III)
     8. 12:19 PM - =?utf-8?Q?Re:__Fusible_links? ()
     9. 02:02 PM - Always on supply (donjohnston)
    10. 02:15 PM - Re: Fusible links (Robert L. Nuckolls, III)
    11. 02:56 PM - Re: Fusible links (B Tomm)
    12. 04:24 PM - Re: Re: Touchy (Bill Bradburry)
    13. 07:10 PM - Re: Fusible links (Lyle Peterson)
    14. 08:53 PM - Re: Fusible links (B Tomm)
    15. 09:22 PM - Sending two msgs to the list (Bill Bradburry)
 
 
 


Message 1


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    Time: 07:14:08 AM PST US
    From: Joe <fransew@gmail.com>
    Subject: Touchy
    There is an old saying, "Beggars can't be choosy." That applies to the AeroElectric List where replies are posted by volunteers. If I volunteered to help someone who then complained about my work, I would stop giving help. There is one very knowledgeable volunteer on the AeroElectric list who sometimes gives long winded and philosophical responses. Sometimes his response answers my question and sometimes not. Regardless, I appreciate it that he has volunteered his precious time to address my issue. There are many other participants on this forum who are also very knowledgeable. Some of them might not post a response to a question because they are afraid of getting flamed. So please treat everyone with respect. Do not post something that you would not say face to face. As for a question not being answered, maybe the question needs to be rephrased or needs to be more specific. Joe Gores


    Message 2


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    Time: 08:24:36 AM PST US
    From: rayj <raymondj@frontiernet.net>
    Subject: Re: Touchy
    Test, please ignore. do not archive -- Raymond Julian Kettle River, MN The things we admire in men, kindness and generosity, openness, honesty, understanding and feeling are the concomitants of failure in our system. And those traits we detest, sharpness, greed, acquisitiveness, meanness, egotism and self-interest are the traits of success. And while men admire the quality of the first they love the produce of the second. -John Steinbeck, novelist, Nobel laureate (1902-1968)


    Message 3


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    Time: 08:27:34 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Fusible links
    At 15:53 2014-12-02, you wrote: Thanks Bob, I had done it on mine a couple years back, but the other day I was helping a hangar neighbour make some improvements. He has a rear mounted battery on a BD4 (engine in front). He has one electronic ignition which was powered by an 18 awg wire connected on the firewall at the input power terminal at the starter solenoid. This fat wire was only powered when the master solenoid (located in back next to the battery) was active. Not ideal for electrically dependant ignition. There was a spare 18 awg wire already running all the way back to the battery and the owner wanted to use that. I suggested that we fuse it but that fuse would have to activate "slower" than the breaker on the panel. I therefore suggested a fusible link and that is where I crossed the line. Since it was such a good idea, and I had suggested it, it was suggested that I do it :) Not a problem since I had materials left over. Just couldn't remember if the 22awg wire (now hidden under the silicone impregnated sleeve) on my RV7 had been stripped or not. My thinking initially was that it must have been stripped because we really don't want any combustible material "inside" the fuse if possible. It didn't strip well, so I re-did it without stripping as you have confirmed. Thank you. Okay, this is a situation similar to the "bus extension" to panel mounted breaker for a crowbar ov protection system. Keep in mind that circuit protection is to keep the smoke in wires. Further, the 'rule of thumb' for always hot wires from a battery bus is to protect at 5A or less Given that fuses are MUCH faster than breakers . . . 7A fuse is a comfortable alternative to the 5A breaker. This is a convention driven by concerns for crash safety. Limit the energy available on an always-hot wire for the purposes of reducing risk of post crash fire. I don't believe for a minute that anyone did any tests combined with statistical analysis to come up with that 5A number . . . but intuitively, one finds comfort in protecting an always-hot wire at the lowest practical value. I suspect that the electronic ignition runs on MUCH less than 5A. What size is the panel mounted breaker? If it were my airplane, I'd drive the ignition supply wire from the battery through a 7A fuse and eliminate the panel mounted breaker. If that breaker EVER trips, then there's something seriously wrong with either the ignition system or the power pathway feeding it . . . the notion of resetting it is does not stand on favorable probabilities for recovery-by-reset. A 7A fuse, 5A breaker, or fusible link in the tail does not alter the probabilities . . . Bob . . .


    Message 4


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    Time: 09:16:09 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Toroid beads VOR antenna vs. Active VOR antenna
    > > >All perfectly doable. I just need to get a better understanding of >the necessities of your request. > >Thanks again, >James Understand. My current vision of this antenna suggests that it will look like a piece of RG coax with a little "lump" of a splice onto a 6-inch piece of wire. The 'lumpy splice' will contain a handful of components that allows the relatively poor antenna to deliver energy into the 50-ohm coax (end impedance of too-short element is WAAayyyy to high). A little background: Active antennas have been around for a long time. Adding some form of amplifier with a high input impedance to the antenna-end of a low impedance coax allows the 'crippled' but still quite serviceable antenna to deliver its energy into the low impedance feed line. Here are some examples: http://tinyurl.com/npdmnsw In particular, I'll call your attention to one of many versions described. Check out the "AA7" . .. Active Antenna AA-7 HF/VHF/UHF, 3-3000MHz It has an HF, VHF 'band' switch. You'll note that in the VHF position, the active circuitry consists of the single transistor and a couple of passive components. The circuit I posted earlier . . . Emacs! was an adaptation of the AA7 configuration. Most active antenna designs bring rf energy down the feed line and send dc power up to the antenna on the same feed line. I decided to keep coax installation as pristine as possible and not mess with the feed line after it leaves the antenna. So, the ready-to-install antenna assembly takes on the form described above where you hopefully will be able to offer a conduit through which the antenna can be extended into the wing. To eliminate the 'monkey motion' at the receiver end of the coax, dc power will have to be brought out to the amplifier on a separate, 22 awg wire that can be fed from the same breaker as the radio . . . The ferrite transformer cores came in last week. I need to brass-board this thing on the bench and verify performance before I squish it down into that 'lump' described earlier. An interesting and important feature of this experiment is to not glass the critter into place so that any future fiddling with the design doesn't take a hack saw to the airplane. I may mount one of this things on my roof and see how it compares with monitor antennas I have for listening to local city, police and fire services. I have one HF active antenna up there already. http://tinyurl.com/ou2ezdy The 'antenna' part of this critter is only a few inches long. I don't have any other HF optimized antennas up yet to compare it to . . . but this 'lump' on the end of a piece of coax hears 'lots of stuff'. Given that the 'stuff' of which VOR is made (high power, line of sight) it seems that our little experiment has a high probability of success for replacing the legacy dipoles and whiskers so favored by our TC brothers. Bob . . .


    Message 5


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    Time: 09:17:49 AM PST US
    From: Charlie England <ceengland7@gmail.com>
    Subject: Re: Fusible links
    On 12/3/2014 10:26 AM, Robert L. Nuckolls, III wrote: > <nuckolls.bob@aeroelectric.com> > > > At 15:53 2014-12-02, you wrote: > Thanks Bob, > > I had done it on mine a couple years back, but the other day I was > helping a hangar neighbour make some improvements. He has a rear > mounted battery on a BD4 (engine in front). He has one electronic > ignition which was powered by an 18 awg wire connected on the firewall > at the input power terminal at the starter solenoid. This fat wire was > only powered when the master solenoid (located in back next to the > battery) was active. Not ideal for electrically dependant ignition. > There was a spare 18 awg wire already running all the way back to the > battery and the owner wanted to use that. I suggested that we fuse it > but that fuse would have to activate "slower" than the breaker on the > panel. I therefore suggested a fusible link and that is where I > crossed the line. Since it was such a good idea, and I had suggested > it, it was suggested that I do it :) Not a problem since I had > materials left over. Just couldn't remember if the 22awg wire (now > hidden under the silicone impregnated sleeve) on my RV7 had been > stripped or not. My thinking initially was that it must have been > stripped because we really don't want any combustible material > "inside" the fuse if possible. It didn't strip well, so I re-did it > without stripping as you have confirmed. Thank you. > > Okay, this is a situation similar > to the "bus extension" to panel mounted > breaker for a crowbar ov protection > system. > > Keep in mind that circuit protection is > to keep the smoke in wires. Further, the > 'rule of thumb' for always hot wires from > a battery bus is to protect at 5A or less > Given that fuses are MUCH faster than > breakers . . . 7A fuse is a comfortable > alternative to the 5A breaker. > > This is a convention driven by concerns > for crash safety. Limit the energy available > on an always-hot wire for the purposes of > reducing risk of post crash fire. I don't > believe for a minute that anyone did any > tests combined with statistical analysis > to come up with that 5A number . . . but > intuitively, one finds comfort in protecting > an always-hot wire at the lowest practical > value. > > I suspect that the electronic ignition runs > on MUCH less than 5A. What size is the panel > mounted breaker? If it were my airplane, > I'd drive the ignition supply wire from the > battery through a 7A fuse and eliminate the > panel mounted breaker. > > If that breaker EVER trips, then there's > something seriously wrong with either > the ignition system or the power pathway > feeding it . . . the notion of resetting it > is does not stand on favorable probabilities > for recovery-by-reset. A 7A fuse, 5A breaker, > or fusible link in the tail does not alter > the probabilities . . . > > > Bob . . . Probably a safe assumption for 'traditional' a/c engines with stock fuel delivery, but different for 'alternative' (automotive-based) engines and increasingly, a/c engines, more current is required. Most automotive-based engines use high pressure fuel injection which must be included in current calculations. There's now a growing wave of automotive style injection on a/c engines, as well. High pressure gerotor or roller-vane fuel pumps typically draw 6-10 amps continuous. Even the little turbine style pumps (which must be installed inside the fuel tank; the input must be kept flooded) typically draw 3-4 amps. So total current demand to keep an 'electronic' engine running usually exceeds 10 amps; often as high as 15. So what's the solution? Dedicated fuse bus at the battery to distribute power to the various engine control components? Charlie


    Message 6


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    Time: 10:04:52 AM PST US
    From: <rnjcurtis@charter.net>
    Subject: Re:_AeroElectric-List:_Fusible_links?
    DQoNCg0KDQoNCg0KDQpQcm9iYWJseSBhIHNhZmUgYXNzdW1wdGlvbiBmb3IgJ3RyYWRpdGlvbmFs JyBhL2MgZW5naW5lcyB3aXRoIHN0b2NrIGZ1ZWwgDQpkZWxpdmVyeSwgYnV0IGRpZmZlcmVudCBm b3IgJ2FsdGVybmF0aXZlJyAoYXV0b21vdGl2ZS1iYXNlZCkgZW5naW5lcyBhbmQgDQppbmNyZWFz aW5nbHksIGEvYyBlbmdpbmVzLCBtb3JlIGN1cnJlbnQgaXMgcmVxdWlyZWQuIE1vc3QgDQphdXRv bW90aXZlLWJhc2VkIGVuZ2luZXMgdXNlIGhpZ2ggcHJlc3N1cmUgZnVlbCBpbmplY3Rpb24gd2hp Y2ggbXVzdCBiZSANCmluY2x1ZGVkIGluIGN1cnJlbnQgY2FsY3VsYXRpb25zLiBUaGVyZSdzIG5v dyBhIGdyb3dpbmcgd2F2ZSBvZiANCmF1dG9tb3RpdmUgc3R5bGUgaW5qZWN0aW9uIG9uIGEvYyBl bmdpbmVzLCBhcyB3ZWxsLiBIaWdoIHByZXNzdXJlIA0KZ2Vyb3RvciBvciByb2xsZXItdmFuZSBm dWVsIHB1bXBzIHR5cGljYWxseSBkcmF3IDYtMTAgYW1wcyBjb250aW51b3VzLiANCkV2ZW4gdGhl IGxpdHRsZSB0dXJiaW5lIHN0eWxlIHB1bXBzICh3aGljaCBtdXN0IGJlIGluc3RhbGxlZCBpbnNp ZGUgdGhlIA0KZnVlbCB0YW5rOyB0aGUgaW5wdXQgbXVzdCBiZSBrZXB0IGZsb29kZWQpIHR5cGlj YWxseSBkcmF3IDMtNCBhbXBzLiBTbyANCnRvdGFsIGN1cnJlbnQgZGVtYW5kIHRvIGtlZXAgYW4g J2VsZWN0cm9uaWMnIGVuZ2luZSBydW5uaW5nIHVzdWFsbHkgDQpleGNlZWRzIDEwIGFtcHM7IG9m dGVuIGFzIGhpZ2ggYXMgMTUuDQoNClNvIHdoYXQncyB0aGUgc29sdXRpb24/IERlZGljYXRlZCBm dXNlIGJ1cyBhdCB0aGUgYmF0dGVyeSB0byBkaXN0cmlidXRlIA0KcG93ZXIgdG8gdGhlIHZhcmlv dXMgZW5naW5lIGNvbnRyb2wgY29tcG9uZW50cz8NCg0KDQoNCg0KTWluZSBpcyBzZXQgdXAgd2l0 aCBkdWFsIGVsZWN0cm9uaWMgaWduaXRpb24gYW5kIGR1YWwgZnVlbCBwdW1wcy4gIFdpdGggbXkg ZHVhbCBiYXR0ZXJ5IHN5c3RlbSBJIGhhdmUgMiBmdXNlZCBjaXJjdWl0cyBvZmYgdGhlIG1haW4g YmF0dGVyeSBidXMgZ29pbmcgdG8gaWduaXRpb24gIzEgYW5kIGZ1ZWwgcHVtcCAjMS4gIEZyb20g bXkgQXV4aWxpYXJ5IGJhdHRlcnkgYnVzIEkgaGF2ZSBhbm90aGVyIDIgZnVzZWQgY2lyY3VpdHMg Z29pbmcgdG8gSWduaXRpb24gIzIgYW5kIGZ1ZWwgcHVtcCAjMi4gIFdpdGggdGhpcyBzeXN0ZW0g eW91IGhhdmUgdG90YWwgcmVkdW5kYW5jeSBhbmQgbGltaXRlZCBjdXJyZW50IGluIGVhY2ggd2ly ZS4NCg0KDQpSb2dlcg=


    Message 7


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    Time: 11:20:19 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Fusible links
    Probably a safe assumption for 'traditional' a/c engines with stock fuel delivery, but different for 'alternative' (automotive-based) engines and increasingly, a/c engines, more current is required. Most automotive-based engines use high pressure fuel injection which must be included in current calculations. There's now a growing wave of automotive style injection on a/c engines, as well. High pressure gerotor or roller-vane fuel pumps typically draw 6-10 amps continuous. Even the little turbine style pumps (which must be installed inside the fuel tank; the input must be kept flooded) typically draw 3-4 amps. So total current demand to keep an 'electronic' engine running usually exceeds 10 amps; often as high as 15. So what's the solution? Dedicated fuse bus at the battery to distribute power to the various engine control components? He was talking about an ignition system. Energy to light the fires is quite nominal. Not aware of any ignition that requires more than 3A. Lightspeed's flame throwing CD ignition runs 2.6A at 2700 rpm on a 6 cyl engine. Fuel delivery is another matter and, as you've noted, can be all over the map. TBI systems run on a few amps while some 40+ psi rail fed injector systems can be MUCH higher. I'd treat this like the heavy duty e-bus feeder illustrated in Z-32 . . . except the e-bus alt feed switch becomes a fuel system control switch. The relay could be a solid state device or one of the sealed electro-mechanical critters. This comports nicely with the TC aircraft philosophy for achieving a Max-Cold state of all wires when crew operated switches are placed to OFF. Bob . . .


    Message 8


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    Time: 12:19:42 PM PST US
    From: <rnjcurtis@charter.net>
    Subject: Re:_AeroElectric-List:_Fusible_links?
    DQoNCg0KDQoNCg0KDQogTm90IGF3YXJlIG9mDQogICAgYW55IGlnbml0aW9uIHRoYXQgcmVxdWly ZXMgbW9yZSB0aGFuIDNBLiBMaWdodHNwZWVkJ3MNCiAgICBmbGFtZSB0aHJvd2luZyBDRCBpZ25p dGlvbiBydW5zIDIuNkEgYXQgMjcwMCBycG0gb24NCiAgICBhIDYgY3lsIGVuZ2luZS4NCg0KDQoN CklmIHlvdSBhcmUgdXNpbmcgYSBQU1JVIChwcm9wZWxsZXIgc3BlZWQgcmVkdWN0aW9uIHVuaXQp IG9uIGEgNiBjeWxpbmRlciBlbmdpbmUgeW91IHdpbGwgaGF2ZSBhIGhpZ2hlciBlbmdpbmUgUlBN LCBwZXJoYXBzIGluIHRoZSByYW5nZSBvZiA0IC0gNSBrIHJwbS4gIFRoaXMgaGlnaGVyIHNwZWVk IHdpbGwgdHJhbnNsYXRlIHRvIGEgaGlnaGVyIGN1cnJlbnQgZmxvdyB0byB0aGUgZWxlY3Ryb25p YyBDRCBpZ25pdGlvbi4gIEFuIE1TRCA2QSBhdXRvbW90aXZlIENEIGlnbml0aW9uIG1vZHVsZSBp cyBzcGVjaWZpZWQgYXQgMUEgLyAxSyBSUE0sIHdoaWNoIHRyYW5zbGF0ZXMgdG8gcGVyaGFwcyA1 QSB3b3JzdCBjYXNlLg0KDQoNClJvZ2Vy


    Message 9


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    Time: 02:02:01 PM PST US
    Subject: Always on supply
    From: "donjohnston" <don@velocity-xl.com>
    The GPS manufacturer suggests connecting a second, always on, supply (they call it "clock power") which will improve GPS position acquisition time. What is the preferred way of providing this power? Run a fused line (they recommend a .1a fuse) directly from a battery terminal (or battery side of the master solenoid) to the GPS? IIRC, the EFIS would like one of these always on supplies also. So maybe run a fused wire from the battery to the panel and create an "always on" bus with fused branches off of that? Read this topic online here: http://forums.matronics.com/viewtopic.php?p=435279#435279


    Message 10


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    Time: 02:15:02 PM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Fusible links
    At 14:08 2014-12-03, you wrote: > Not aware of > any ignition that requires more than 3A. Lightspeed's > flame throwing CD ignition runs 2.6A at 2700 rpm on > a 6 cyl engine. > > >If you are using a PSRU (propeller speed reduction unit) on a 6 >cylinder engine you will have a higher engine RPM, perhaps in the >range of 4 - 5 k rpm. This higher speed will translate to a higher >current flow to the electronic CD ignition. An MSD 6A automotive CD >ignition module is specified at 1A / 1K RPM, which translates to >perhaps 5A worst case. Hmmmm . . . that's too bad. There's no good reason for ignition systems to draw that much current. I've talked with the guys at EmagAir about this several times. A take-away from those conversations says that it's most important to get an adequate spark delivered right on time. Magnetos have proven their ability to deliver adequate sparks while running . . . and they're certainly not flame throwers. Certainly hard to fiddle with the timing . . . and you need some kind of monkey motion like impulse couplers or shower-of-sparks to effect nice starts . . . but there's hundreds of thousands flying with few critical issues. Being able to advance the spark at low manifold pressures gets you some benefit . . .but the spark doesn't need to be any hotter . . . in fact, worst case sparking requirements are at max cylinder pressure which probably means a boosted engine at max retard timing. The legacy Kettering coil, condenser, points system delivers about 30-40 mJ per spark. For a 6-cyl engine running 2400 rpm, 40 rev/sec, 3 sparks per rev, energy at the plugs comes to about 120 mJ per rev or 4800 mJ per second. Assume a really lousy system efficiency of say 50% and we need to draw 9.6 watts from the ship's bus or about 700 mA. Now, deliver that energy even while cold and with a soggy battery . . . and be able to advance the timing at low manifold pressures, and you've got a perfectly adequate ignition system. So be curious and skeptical when someone says their 'flame throwing ignition system' is going to do great things for your airplane. If you're flying a racer, maybe. If you've got a nice point-a to point-b transportation machine that carries battery energy to implement Plan-B, perhaps all that flame at the spark plugs suggests a need to re-think the planning. Elegant solutions benefit from good stewardship of energy. It starts with the airfoils and extends down to batteries and fuel aboard. Bob . . .


    Message 11


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    Time: 02:56:54 PM PST US
    From: "B Tomm" <fvalarm@rapidnet.net>
    Subject: Fusible links
    Thanks Bob, The literature that came with the LightSpeed says the breaker should be 7.5 amp. (IO-540) You still recommend a 5 amp breaker (since he really wants some form of disconnect on the panel) and a (??? Value fuse, fusible link, breaker)at the rear for the feed from the battery. Perhaps I should suggest a 5 or 7.5 amp slow blo fuse at the battery, and a simple switch on the panel in place of the breaker if he must have a disconnect. Bevan -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Wednesday, December 03, 2014 8:27 AM Subject: RE: AeroElectric-List: Fusible links --> <nuckolls.bob@aeroelectric.com> At 15:53 2014-12-02, you wrote: Thanks Bob, I had done it on mine a couple years back, but the other day I was helping a hangar neighbour make some improvements. He has a rear mounted battery on a BD4 (engine in front). He has one electronic ignition which was powered by an 18 awg wire connected on the firewall at the input power terminal at the starter solenoid. This fat wire was only powered when the master solenoid (located in back next to the battery) was active. Not ideal for electrically dependant ignition. There was a spare 18 awg wire already running all the way back to the battery and the owner wanted to use that. I suggested that we fuse it but that fuse would have to activate "slower" than the breaker on the panel. I therefore suggested a fusible link and that is where I crossed the line. Since it was such a good idea, and I had suggested it, it was suggested that I do it :) Not a problem since I had materials left over. Just couldn't remember if the 22awg wire (now hidden under the silicone impregnated sleeve) on my RV7 had been stripped or not. My thinking initially was that it must have been stripped because we really don't want any combustible material "inside" the fuse if possible. It didn't strip well, so I re-did it without stripping as you have confirmed. Thank you. Okay, this is a situation similar to the "bus extension" to panel mounted breaker for a crowbar ov protection system. Keep in mind that circuit protection is to keep the smoke in wires. Further, the 'rule of thumb' for always hot wires from a battery bus is to protect at 5A or less Given that fuses are MUCH faster than breakers . . . 7A fuse is a comfortable alternative to the 5A breaker. This is a convention driven by concerns for crash safety. Limit the energy available on an always-hot wire for the purposes of reducing risk of post crash fire. I don't believe for a minute that anyone did any tests combined with statistical analysis to come up with that 5A number . . . but intuitively, one finds comfort in protecting an always-hot wire at the lowest practical value. I suspect that the electronic ignition runs on MUCH less than 5A. What size is the panel mounted breaker? If it were my airplane, I'd drive the ignition supply wire from the battery through a 7A fuse and eliminate the panel mounted breaker. If that breaker EVER trips, then there's something seriously wrong with either the ignition system or the power pathway feeding it . . . the notion of resetting it is does not stand on favorable probabilities for recovery-by-reset. A 7A fuse, 5A breaker, or fusible link in the tail does not alter the probabilities . . . Bob . . .


    Message 12


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    Time: 04:24:59 PM PST US
    From: "Bill Bradburry" <bbradburry@verizon.net>
    Subject: Re: Touchy
    I was being "cute" with the uninteresting comment, Bob. I suspect that everything on the list is interesting to someone on the list, although maybe not to everybody on the list. I think I get something even from the posts that I don't quite understand and for sure from the posts counseling the need for something someone wants to do. Sometimes I agree and sometimes not, but an opinion not your own can sometimes turn on a light bulb. When my questions get ignored I just assume that no one reading that day has a suggestion that he feels strongly about enough to post. It is disappointing though, when you really kinda want a suggestion and don't get anything and then some fairly basic thing will get 10 hits. :>) But I am not criticizing the list, because God knows, I am flying an airplane the parts of which would still be scattered all over the hangar if it had not been for the good and generous graces if Bob N. and the others on this list. Bill _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert Borger Sent: Tuesday, December 02, 2014 9:15 AM Subject: Re: AeroElectric-List: Re: Touchy Bill, I understand your unanswered requests for help. It's not that they are uninteresting. It's because I don't have an answer and I don't want to be one of the ones cluttering up the list with speculation or proposing alternatives you don't need. Blue skies & tailwinds, Bob Borger Europa XS Tri, Rotax 914, Airmaster C/S Prop (75 hrs). Little Toot Sport Biplane, Lycoming Thunderbolt AEIO-320 EXP 3705 Lynchburg Dr. Corinth, TX 76208-5331 Cel: 817-992-1117 <mailto:rlborger@mac.com> rlborger@mac.com On Dec 2, 2014, at 8:13 AM, Bill Bradburry <bbradburry@verizon.net> wrote: Stan, Very well said. A similar problem with the list is when there is no response at all. This happens to me quite frequently. I suppose it would help if I had more interesting problems. :>) Bill


    Message 13


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    Time: 07:10:23 PM PST US
    From: Lyle Peterson <lyleap@centurylink.net>
    Subject: Re: Fusible links
    Hi, I've been involved in electronics for some 30 years. I know what a fusible link is in an automobile. They do come in a variety of designs, some very much like a fuse as we know them. I have always questioned the value of a fusible link such as is used in automobiles. They are a length of wire, usually 4 wire gauges smaller than the wire they are protecting. They are most often a hassle to replace. Why would not a common fuse perform the same function and be much more easily replaced? Inquiring minds want to know, Lyle On 12/3/2014 4:14 PM, Robert L. Nuckolls, III wrote: > <nuckolls.bob@aeroelectric.com> > > At 14:08 2014-12-03, you wrote: > > >> Not aware of >> any ignition that requires more than 3A. Lightspeed's >> flame throwing CD ignition runs 2.6A at 2700 rpm on >> a 6 cyl engine. >> >> >> If you are using a PSRU (propeller speed reduction unit) on a 6 >> cylinder engine you will have a higher engine RPM, perhaps in the >> range of 4 - 5 k rpm. This higher speed will translate to a higher >> current flow to the electronic CD ignition. An MSD 6A automotive CD >> ignition module is specified at 1A / 1K RPM, which translates to >> perhaps 5A worst case. > > -- Lyle Sent from my Gateway E4610D desktop


    Message 14


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    Time: 08:53:03 PM PST US
    From: "B Tomm" <fvalarm@rapidnet.net>
    Subject: Fusible links
    The advantages of the fusible link in this case is: Must be slower acting than the breaker. I blew quite a few fuses until I found that I needed a fuse of about double the value to ensure the breaker trips first. This would suggest a 15 amp fuse which is larger than desired. Robust (although a fuse in an inline holder is equally suitable in this regard.) There's no place to mount a breaker near the battery where it is easily accessible and yet not in the way for battery access through the small panel where it is located. Cost and availability. We're trying to get this airplane back in the air so it can go home. They can make more permanent changes there. Bevan -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Lyle Peterson Sent: Wednesday, December 03, 2014 7:08 PM Subject: Re: AeroElectric-List: Fusible links --> <lyleap@centurylink.net> Hi, I've been involved in electronics for some 30 years. I know what a fusible link is in an automobile. They do come in a variety of designs, some very much like a fuse as we know them. I have always questioned the value of a fusible link such as is used in automobiles. They are a length of wire, usually 4 wire gauges smaller than the wire they are protecting. They are most often a hassle to replace. Why would not a common fuse perform the same function and be much more easily replaced? Inquiring minds want to know, Lyle On 12/3/2014 4:14 PM, Robert L. Nuckolls, III wrote: > <nuckolls.bob@aeroelectric.com> > > At 14:08 2014-12-03, you wrote: > > >> Not aware of >> any ignition that requires more than 3A. Lightspeed's >> flame throwing CD ignition runs 2.6A at 2700 rpm on >> a 6 cyl engine. >> >> >> If you are using a PSRU (propeller speed reduction unit) on a 6 >> cylinder engine you will have a higher engine RPM, perhaps in the >> range of 4 - 5 k rpm. This higher speed will translate to a higher >> current flow to the electronic CD ignition. An MSD 6A automotive CD >> ignition module is specified at 1A / 1K RPM, which translates to >> perhaps 5A worst case. > > -- Lyle Sent from my Gateway E4610D desktop


    Message 15


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    Time: 09:22:01 PM PST US
    From: "Bill Bradburry" <bbradburry@verizon.net>
    Subject: Sending two msgs to the list
    I seem to be sending two msgs to the list each time I post. I am using Outlook. Does anyone know why this may be happening? It appears to have started a couple of days ago. The msgs are about 12 minutes apart and I am only hitting send one time. AFAIK it is only happening with msgs to the Aeroelectric list. Thanks for any ideas. Bill




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