---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 08/28/16: 14 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:36 AM - Under Sized Wire (user9253) 2. 05:06 AM - Re: Under Sized Wire (racerjerry) 3. 08:07 AM - Re: Re: Under Sized Wire (Kelly McMullen) 4. 08:29 AM - Re: Re: Under Sized Wire (Rene) 5. 08:35 AM - Re: Re: Under Sized Wire (Charlie England) 6. 08:58 AM - Re: Under Sized Wire (Robert L. Nuckolls, III) 7. 09:06 AM - Re: Re: Under Sized Wire (A R Goldman) 8. 10:27 AM - Re: Connectors for Wing Roots (Robert L. Nuckolls, III) 9. 11:17 AM - Re: Connectors for Wing Roots (rayj) 10. 12:19 PM - Re: Connectors for Wing Roots (Charlie England) 11. 02:11 PM - Re: Re: Under Sized Wire (Kelly McMullen) 12. 06:37 PM - Re: Re: Under Sized Wire (Robert L. Nuckolls, III) 13. 07:24 PM - Re: Re: Under Sized Wire (Rene) 14. 08:28 PM - Re: Connectors for Wing Roots (ashleysc@broadstripe.net) ________________________________ Message 1 _____________________________________ Time: 04:36:11 AM PST US Subject: AeroElectric-List: Under Sized Wire From: "user9253" On page 20 of the October 2016 issue of Kitplanes Magazine, the author wrote, > "On one very nicely equipped RV-10, there was a 14 AWG wire being used as the main feed from the alternator. It was not only improperly sized, but also a potential fire hazard, as it was attached to a 60-amp alternator breaker. Clearly, the wire would have melted before the breaker could have activated." I agree that the wire was very undersized and would get very hot. But would it actually melt? -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=459972#459972 ________________________________ Message 2 _____________________________________ Time: 05:06:58 AM PST US Subject: AeroElectric-List: Re: Under Sized Wire From: "racerjerry" The REAL problem is smoke in the cockpit, shortly followed by incapacitation. Incapacitation happens long before the wire insulation turns to snot. Aircraft wire MUCH BETTER - avoid auto parts store PVC insulated wire. Use AC 43.13-1B as a guide and you will not go wrong. Available here: http://www.faa.gov/regulations_policies/advisory_circulars/index.cfm/go/document.information/documentID/99861 -------- Jerry King Read this topic online here: http://forums.matronics.com/viewtopic.php?p=459975#459975 ________________________________ Message 3 _____________________________________ Time: 08:07:56 AM PST US Subject: Re: AeroElectric-List: Re: Under Sized Wire From: Kelly McMullen Not sure whether the builder ever saw Van's wiring diagram for the RV-10, and certainly could not have purchased the optional wiring kit. it uses AWG 8 aircraft wire for alternator to bus, and 8 AWG for starter relay to bus, so both battery feed and alternator feed to bus is appropriate. Master relay to starter relay is 2 AWG. My RV-10 runs about 15 amps with everything in the panel plus strobes and nav lights, landing lights or pitot heat each add about 10 amps. Battery recharge after start will up the flow to a bit over 40 amps for a few minutes. Never have seen the current output of alternator get close to the rated 60 amps. I suppose a night start with landing lights needed could get there. On 8/28/2016 5:05 AM, racerjerry wrote: > > The REAL problem is smoke in the cockpit, shortly followed by incapacitation. Incapacitation happens long before the wire insulation turns to snot. > > Aircraft wire MUCH BETTER - avoid auto parts store PVC insulated wire. > > Use AC 43.13-1B as a guide and you will not go wrong. > Available here: > http://www.faa.gov/regulations_policies/advisory_circulars/index.cfm/go/document.information/documentID/99861 > > -------- > Jerry King > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=459975#459975 > > ________________________________ Message 4 _____________________________________ Time: 08:29:56 AM PST US From: "Rene" Subject: RE: AeroElectric-List: Re: Under Sized Wire Just FYI, after losing my first two alternators I upgraded to the Plane Power 70 amp. I left the 60amp breaker in the feed line. Worked fine....until I was on a long trip to FLA and it tripped the breaker. Three times......after take off and I think it was related to keying up the mic. Also, it happened on the second leg of the day....hot day....engine heat soaked. I upgraded to a 70 AMP breaker.....all is fine. My amp meter measures the flow to and from the main battery. So no real help there in determining if I was really seeing 70 amps. My calculated max load is nowhere near that.... Rene' 801-721-6080 -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Kelly McMullen Sent: Sunday, August 28, 2016 9:05 AM Subject: Re: AeroElectric-List: Re: Under Sized Wire --> Not sure whether the builder ever saw Van's wiring diagram for the RV-10, and certainly could not have purchased the optional wiring kit. it uses AWG 8 aircraft wire for alternator to bus, and 8 AWG for starter relay to bus, so both battery feed and alternator feed to bus is appropriate. Master relay to starter relay is 2 AWG. My RV-10 runs about 15 amps with everything in the panel plus strobes and nav lights, landing lights or pitot heat each add about 10 amps. Battery recharge after start will up the flow to a bit over 40 amps for a few minutes. Never have seen the current output of alternator get close to the rated 60 amps. I suppose a night start with landing lights needed could get there. On 8/28/2016 5:05 AM, racerjerry wrote: > --> > > The REAL problem is smoke in the cockpit, shortly followed by incapacitation. Incapacitation happens long before the wire insulation turns to snot. > > Aircraft wire MUCH BETTER - avoid auto parts store PVC insulated wire. > > Use AC 43.13-1B as a guide and you will not go wrong. > Available here: > http://www.faa.gov/regulations_policies/advisory_circulars/index.cfm/g > o/document.information/documentID/99861 > > -------- > Jerry King > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=459975#459975 > > ________________________________ Message 5 _____________________________________ Time: 08:35:13 AM PST US Subject: Re: AeroElectric-List: Re: Under Sized Wire From: Charlie England Note that all context was lost in replying to an email that only included advice to avoid PVC insulated wire (which isn't really that big a deal; there's just better stuff available now). On the subject of using 14awg wire on a 60 amp alternator: The point is not what is a typical draw; it's what the wire could potentially see. The mantra is: size the wire for the load (which can be a bit more than the *rated* capacity of the alternator, if the battery happened to be really low, or there were lots of loads like landing lights, pitot heat, etc), then fuse to protect the wire. And none of us has answered the original question: Would the wire melt? I don't know the answer for sure, but I do recall the rule of thumb for fuseable links: make the link 4 wire sizes under the wire size you're protecting. Ex: a #12 fuseable link wire protects a #8 wire. So, if a #8 is actually needed, #14 sounds like a quick blow fuse to me. Charlie On 8/28/2016 10:05 AM, Kelly McMullen wrote: > > > Not sure whether the builder ever saw Van's wiring diagram for the > RV-10, and certainly could not have purchased the optional wiring kit. > it uses AWG 8 aircraft wire for alternator to bus, and 8 AWG for > starter relay to bus, so both battery feed and alternator feed to bus > is appropriate. Master relay to starter relay is 2 AWG. My RV-10 runs > about 15 amps with everything in the panel plus strobes and nav > lights, landing lights or pitot heat each add about 10 amps. Battery > recharge after start will up the flow to a bit over 40 amps for a few > minutes. Never have seen the current output of alternator get close to > the rated 60 amps. I suppose a night start with landing lights needed > could get there. > > On 8/28/2016 5:05 AM, racerjerry wrote: >> >> >> The REAL problem is smoke in the cockpit, shortly followed by >> incapacitation. Incapacitation happens long before the wire >> insulation turns to snot. >> >> Aircraft wire MUCH BETTER - avoid auto parts store PVC insulated wire. >> >> Use AC 43.13-1B as a guide and you will not go wrong. >> Available here: >> http://www.faa.gov/regulations_policies/advisory_circulars/index.cfm/go/document.information/documentID/99861 >> >> >> -------- >> Jerry King ________________________________ Message 6 _____________________________________ Time: 08:58:41 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Under Sized Wire At 06:34 AM 8/28/2016, you wrote: > >On page 20 of the October 2016 issue of Kitplanes Magazine, the author wrote, > > "On one very nicely equipped RV-10, there was a 14 AWG wire being > used as the main feed from the alternator. It was not only > improperly sized, but also a potential fire hazard, as it was > attached to a 60-amp alternator breaker. Clearly, the wire would > have melted before the breaker could have activated." > I agree that the wire was very undersized and would get very > hot. But would it actually melt? Interesting question. You may recall the experiment I conducted on a 20 AMP load through a 22AWG Tefzel wire on the workbench some years back. While the wire did run hot (and voltage drop was no doubt higher than one would like) the jacket temperature stabilized well below maximum ratings for the insulation. http://tinyurl.com/6qr72fr I suspect a 14AWG hanging out in open air would not be seriously challenged for survival at 60A . . . but running the wire into bundles of other wires would have a profound influence on its ability to reject heat. Wire ratings are not so much a function of the copper but of the insulation, energy dissipated in the wire, temperature rise due to dissipation of that energy and ability to dump BTUs off into the environment. Insulation . . . and materials in contact with that insulation are the potential victims at risk. Bob . . . ________________________________ Message 7 _____________________________________ Time: 09:06:38 AM PST US From: A R Goldman Subject: Re: AeroElectric-List: Re: Under Sized Wire Yes the wire will melt -or-not depending on its gauge and the amount of overload. If my memory serves me correctly the fanles specify that a particular gauge will handle a particular amperage and with these variables will increase its temperature by so many degrees The wire won't melt until the temperature gets to the melting point of copper or whatever material it is made of. However the heat rise can cause all types of hurt as it starts to degrade the insulation and you get the characteristic electrical fire smell. Bundled wires have a smaller rating as the heat produced can effect adjacent wires So with a slight overload the wires will Probably not melt A larger gauge will of course maintain more heat and possibly become a greater hazard Now add the situation of an undersized wire and a large current flow and it will indeed melt explosively-- or "fuse" which will Break the circuit. In fact thrall is what a fuse or fusable link is. The difference is that they are usually thermally protected and placed in a safe access able area Rich Sent from my iPhone > On Aug 28, 2016, at 10:37 AM, Charlie England wrote: > > > Note that all context was lost in replying to an email that only included advice to avoid PVC insulated wire (which isn't really that big a deal; there's just better stuff available now). > > On the subject of using 14awg wire on a 60 amp alternator: The point is not what is a typical draw; it's what the wire could potentially see. The mantra is: size the wire for the load (which can be a bit more than the *rated* capacity of the alternator, if the battery happened to be really low, or there were lots of loads like landing lights, pitot heat, etc), then fuse to protect the wire. > > And none of us has answered the original question: Would the wire melt? I don't know the answer for sure, but I do recall the rule of thumb for fuseable links: make the link 4 wire sizes under the wire size you're protecting. Ex: a #12 fuseable link wire protects a #8 wire. So, if a #8 is actually needed, #14 sounds like a quick blow fuse to me. > > Charlie > >> On 8/28/2016 10:05 AM, Kelly McMullen wrote: >> >> Not sure whether the builder ever saw Van's wiring diagram for the RV-10, and certainly could not have purchased the optional wiring kit. it uses AWG 8 aircraft wire for alternator to bus, and 8 AWG for starter relay to bus, so both battery feed and alternator feed to bus is appropriate. Master relay to starter relay is 2 AWG. My RV-10 runs about 15 amps with everything in the panel plus strobes and nav lights, landing lights or pitot heat each add about 10 amps. Battery recharge after start will up the flow to a bit over 40 amps for a few minutes. Never have seen the current output of alternator get close to the rated 60 amps. I suppose a night start with landing lights needed could get there. >> >>> On 8/28/2016 5:05 AM, racerjerry wrote: >>> >>> The REAL problem is smoke in the cockpit, shortly followed by incapacitation. Incapacitation happens long before the wire insulation turns to snot. >>> >>> Aircraft wire MUCH BETTER - avoid auto parts store PVC insulated wire. >>> >>> Use AC 43.13-1B as a guide and you will not go wrong. >>> Available here: >>> http://www.faa.gov/regulations_policies/advisory_circulars/index.cfm/go/document.information/documentID/99861 >>> >>> -------- >>> Jerry King > > > > > ________________________________ Message 8 _____________________________________ Time: 10:27:06 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Connectors for Wing Roots The Matronics server seems to no longer allow embedded images. Here's a re-post of my comment along with a link to the picture At 11:30 AM 8/26/2016, you wrote: >Not familiar with "handshake connectors." Please amplify and provide >mfg. and pt. no. >Cheers! Stu. Here is one modern incarnation of a T&B terminal we used to use on the Cessna twin engine line. As you can see, they're not cheap. They're certainly secure in tension . . . but no more so than a knife splice. http://tinyurl.com/z5nx9h3 I've got some 40 year old wrist-locks around here somewhere . . . shows you how often I've been excited about using them. Bob . . . ________________________________ Message 9 _____________________________________ Time: 11:17:15 AM PST US Subject: Re: AeroElectric-List: Connectors for Wing Roots From: rayj The picture and the table of prices came through to me in email. 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) On 08/28/2016 12:17 PM, Robert L. Nuckolls, III wrote: > The Matronics server seems to no longer allow > embedded images. Here's a re-post of my comment > along with a link to the picture > > At 11:30 AM 8/26/2016, you wrote: >> Not familiar with "handshake connectors." Please amplify and provide >> mfg. and pt. no. >> Cheers! Stu. > > > Here is one modern incarnation of a T&B terminal > we used to use on the Cessna twin engine line. > As you can see, they're not cheap. They're certainly > secure in tension . . . but no more so than a > knife splice. > > http://tinyurl.com/z5nx9h3 > > I've got some 40 year old wrist-locks around here > somewhere . . . shows you how often I've been > excited about using them. > > > Bob . . . > ________________________________ Message 10 ____________________________________ Time: 12:19:38 PM PST US Subject: Re: AeroElectric-List: Connectors for Wing Roots From: Charlie England Bob, Same here. However, when I tried to reply to that email (the reply included the images from your original post), the Matronics server rejected my reply. I then deleted the images from my reply, and the server accepted it. That's not the 1st time it's happened to me in replying to one of your emails that had embedded images, so apparently it must alter something in the image when it 'broadcasts' the original email, and the resultant altered image isn't allowed to come back into the server. Charlie On 8/28/2016 1:13 PM, rayj wrote: > > The picture and the table of prices came through to me in email. > > 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) > > On 08/28/2016 12:17 PM, Robert L. Nuckolls, III wrote: >> The Matronics server seems to no longer allow >> embedded images. Here's a re-post of my comment >> along with a link to the picture >> >> At 11:30 AM 8/26/2016, you wrote: >>> Not familiar with "handshake connectors." Please amplify and provide >>> mfg. and pt. no. >>> Cheers! Stu. >> >> >> >> Here is one modern incarnation of a T&B terminal >> we used to use on the Cessna twin engine line. >> As you can see, they're not cheap. They're certainly >> secure in tension . . . but no more so than a >> knife splice. >> >> http://tinyurl.com/z5nx9h3 >> >> I've got some 40 year old wrist-locks around here >> somewhere . . . shows you how often I've been >> excited about using them. >> >> >> Bob . . . >> > ________________________________ Message 11 ____________________________________ Time: 02:11:55 PM PST US Subject: Re: AeroElectric-List: Re: Under Sized Wire From: Kelly McMullen I never saw the context with regard to PVC insulation. Not in the Kitplanes article,nor other messages here. The subject line was and is undersized wire. 14 AWG will carry 60 amps, especially if the run is short, for some period of time, probably not a long time. Question is whether the resistance generates more heat than the insulation can dissipate, and melts the insulation. Likely the load IS quite variable and steady state is no more than 80 percent of alternator capacity, more likely 30 percent. On 8/28/2016 8:37 AM, Charlie England wrote: > > > Note that all context was lost in replying to an email that only > included advice to avoid PVC insulated wire (which isn't really that big > a deal; there's just better stuff available now). ________________________________ Message 12 ____________________________________ Time: 06:37:30 PM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: Re: Under Sized Wire At 10:28 AM 8/28/2016, you wrote: > >Just FYI, after losing my first two alternators I upgraded to the Plane >Power 70 amp. I left the 60amp breaker in the feed line. Worked >fine....until I was on a long trip to FLA and it tripped the breaker. Three >times......after take off and I think it was related to keying up the mic. >Also, it happened on the second leg of the day....hot day....engine heat >soaked. > >I upgraded to a 70 AMP breaker.....all is fine. > >My amp meter measures the flow to and from the main battery. So no real >help there in determining if I was really seeing 70 amps. My calculated max >load is nowhere near that.... This kinda has the 'smell' of a faulty breaker . . . what kind was it and do you still have it? Bob . . . ________________________________ Message 13 ____________________________________ Time: 07:24:20 PM PST US From: "Rene" Subject: RE: AeroElectric-List: Re: Under Sized Wire I might...I will check at the hanger the next time I am out there. From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Sunday, August 28, 2016 7:35 PM Subject: RE: AeroElectric-List: Re: Under Sized Wire At 10:28 AM 8/28/2016, you wrote: Just FYI, after losing my first two alternators I upgraded to the Plane Power 70 amp. I left the 60amp breaker in the feed line. Worked fine....until I was on a long trip to FLA and it tripped the breaker. Three times......after take off and I think it was related to keying up the mic. Also, it happened on the second leg of the day....hot day....engine heat soaked. I upgraded to a 70 AMP breaker.....all is fine. My amp meter measures the flow to and from the main battery. So no real help there in determining if I was really seeing 70 amps. My calculated max load is nowhere near that.... This kinda has the 'smell' of a faulty breaker . . . what kind was it and do you still have it? Bob . . . ________________________________ Message 14 ____________________________________ Time: 08:28:25 PM PST US From: ashleysc@broadstripe.net Subject: Re: AeroElectric-List: Connectors for Wing Roots Hi Bob; I think the "wristlock" is different than the "handshake," but seem to do the same function. Thanks; I didn't know about wristlock either. Cheers! Stu. ----- Original Message ----- From: "Robert L. Nuckolls, III" Sent: Sunday, August 28, 2016 10:17:59 AM Subject: Re: AeroElectric-List: Connectors for Wing Roots The Matronics server seems to no longer allow embedded images. Here's a re-post of my comment along with a link to the picture At 11:30 AM 8/26/2016, you wrote: Not familiar with "handshake connectors." Please amplify and provide mfg. and pt. no. Cheers! Stu. Here is one modern incarnation of a T&B terminal we used to use on the Cessna twin engine line. As you can see, they're not cheap. They're certainly secure in tension . . . but no more so than a knife splice. http://tinyurl.com/z5nx9h3 I've got some 40 year old wrist-locks around here somewhere . . . shows you how often I've been excited about using them. 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