---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 05/22/12: 17 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:49 AM - Re: ELT current demand (Bill Watson) 2. 08:41 AM - Re: Ground plane for GPS antenna? (Brantel) 3. 10:12 AM - Re: Re: AEC9001 Schottky diode in Z-13/8 (rayj) 4. 10:31 AM - Re: AEC9001 Schottky diode in Z-13/8 (Eric M. Jones) 5. 11:02 AM - Re: ELT current demand (Ken) 6. 11:17 AM - Re: Re: AEC9001 Schottky diode in Z-13/8 (rayj) 7. 11:32 AM - Re: AEC9001 Schottky diode in Z-13/8 (Eric M. Jones) 8. 11:55 AM - Re: Re: AEC9001 Schottky diode in Z-13/8 (ROGER & JEAN CURTIS) 9. 11:55 AM - Re: Re: AEC9001 Schottky diode in Z-13/8 (jason@jasonbeaver.com) 10. 11:56 AM - Re: Re: AEC9001 Schottky diode in Z-13/8 (Bob McCallum) 11. 12:28 PM - Re: Re: AEC9001 Schottky diode in Z-13/8 (rayj) 12. 02:54 PM - Re: Re: AEC9001 Schottky diode in Z-13/8 (Nikolaos Napoli) 13. 03:20 PM - Re: AEC9001 Schottky diode in Z-13/8 (MikeDunlop) 14. 05:34 PM - Re: Re: AEC9001 Schottky diode in Z-13/8 (Henador Titzoff) 15. 08:18 PM - Re: Re: AEC9001 Schottky diode in Z-13/8 (Jeff Luckey) 16. 10:58 PM - Feels like voltage to me (Paul Millner) 17. 11:19 PM - Re: Re: Anti Corrosive Zinc Paste (Paul Millner) ________________________________ Message 1 _____________________________________ Time: 05:49:47 AM PST US From: Bill Watson Subject: Re: AeroElectric-List: ELT current demand I installed the ACK E-04 unit. I must admit to total ignorance as to how these things work these days but can share the following. Beyond location and orientation of the main unit, your planning needs to include the remote operation panel (very small but wired to main unit via 4 conductor telephone wire - supplied). Remember that the main unit will probably be behind the cockpit and the remote panel will be on your panel. Though it is mostly self contained, there is a power lead requiring 40mA (practically any wire fuse combination will work). And a GPS input which I think is optional but desirable. The easiest thing may be to pick a unit and download their manual. The ACK unit's manual is here: http://www.ackavionics.com/406%20Page.html Good luck, Bill Watson On 5/21/2012 10:53 AM, f.kyle@sympatico.ca wrote: > Cheers, > I have not yet chosen the model of ELT for inclusion on my Europa, > but must make way for its eventual installation. That means fuse and wire > size choice. > Rather than spend time researching hesitant advertisers, I'm asking > for your advice on the current requirement of your or any ELT. > I am aware of the transmit level but of course it's for such a short time > that there must be an average level plus safe margin with which to work. > Thanks in advance. > Ferg > C-FFGG mono 914 CS prop > ________________________________ Message 2 _____________________________________ Time: 08:41:51 AM PST US Subject: AeroElectric-List: Re: Ground plane for GPS antenna? From: "Brantel" The 430W antenna is an active antenna that needs ~5v phantom power that it gets from the cable/430W unit. >From a Garmin Install Manual: * Antenna Doubler/Backing Plate The antenna installation must provide adequate support for the antenna considering a maximum drag load of 5 lbs. (at subsonic speed). When penetrating the skin with a large hole (i.e. for the coax connector) a doubler plate is required to re-instate the integrity of the aircraft skin. Never weaken the aircraft structure when choosing a mounting area. Make use of any available reinforcements where appropriate. * Antenna Grounding Plane Although no ground plane is required, the antennas typically perform better when a ground plane is used. The ground plane should be a conductive surface as large as practical, with a minimum diameter of 8 inches. To use an antenna in aircraft with fabric or composite skin, a ground plane is recommended. It is usually installed under the skin of the aircraft, below the antenna, and is made of either aluminum sheet or of wire mesh. * Antenna Grounding The antenna is grounded through the mounting hardware and the coax connection. The mounting hardware (washers and nuts) and doubler plate should make contact with an unpainted grounded surface ensuring proper antenna grounding. It is important to have good conductivity between the coaxial shield and the ground plane. The bottom of the antenna does not need to make contact with the ground plane (i.e. the surface may be painted). The antenna will capacitively couple to the ground plane beneath the paint or aircraft cover. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=373574#373574 ________________________________ Message 3 _____________________________________ Time: 10:12:54 AM PST US From: rayj Subject: Re: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 I really have to ask. Are you making the claim that in all the years "Sparky" used his fingers, He NEVER had his fingertips touch at different times? Assuming 60Hz, a difference in contact times of the the fingertips of 1/30 of a second would allow more than enough time for any affect that was going to take place between 1st and 2nd finger contact. Never more than 1/30 of a second, ever. I'm skeptical. Raymond Julian Kettle River, MN "And you know that I could have me a million more friends, and all I'd have to lose is my point of view." - John Prine On 05/20/2012 10:38 AM, Eric M. Jones wrote: > --> AeroElectric-List message posted by: "Eric M. > Jones" > > Bill B.: > > Hard to know. But the lesson is that a voltmeter should never, and I > mean NEVER be used as a makeshift continuity tester. A 12V indicator > lamp is a much better tool. > > I used to know an 85-year old electrician nicknamed Sparky (really) > who told me that in the early days they never used meters, he would > just put his two fingers across the line (even 440V!). But there was > a technique to it--one finger on the hot and one on the ground or > neutral AT THE SAME INSTANT--And don't touch anything else. Same when > removing them. It is easy to do this with 12V, but you have to lick > your fingers and press hard. Every kid knows you can test a 9V > battery on your tongue and a 1.5V cell can be tested UNDER the > tongue. > > -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive > Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=373400#373400 > > ________________________________ Message 4 _____________________________________ Time: 10:31:08 AM PST US Subject: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 From: "Eric M. Jones" > I'm skeptical. Raymond Julian Raymond. It is important to note that the electrical current flowed only up one finger and down the adjacent finger...never through the body, the heart or any bundle of nerves. So it couldn't kill him. Sparky also had tough hands that had done hard work for decades....I didn't doubt him at all. There are lots of seemingly-dangerous electrical tricks...if you know what you're doing. At 440V and 25k ohm dry skin, that's only 18 milliamps RMS. It shouldn't be a problem at all. How about we both try it and report back. YOU FIRST! -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=373577#373577 ________________________________ Message 5 _____________________________________ Time: 11:02:12 AM PST US From: Ken Subject: Re: AeroElectric-List: ELT current demand The E-04 directions are a bit skimpy on the aircraft power connection other than a 1 amp fuse and 40mA nominal. It would seem that it should be fed power whenever the master switch is on. I think the testing procedure implies that aircraft power is being used to process incoming GPS instructions which would imply that gps position info is already current and immediately ready to be transmitted if the ELT activates?? It would seem unlikely to expect to receive remote gps info after an impact. I've also seen vague references to a next gen 406 spec due in 2015 but no specifics. Would be nice if they could actually get the things to transmit a receivable signal even 50% of the time in an accident. Ken On 22/05/2012 8:48 AM, Bill Watson wrote: > > > I installed the ACK E-04 unit. I must admit to total ignorance as to how > these things work these days but can share the following. > > Beyond location and orientation of the main unit, your planning needs to > include the remote operation panel (very small but wired to main unit > via 4 conductor telephone wire - supplied). Remember that the main unit > will probably be behind the cockpit and the remote panel will be on your > panel. > > Though it is mostly self contained, there is a power lead requiring 40mA > (practically any wire fuse combination will work). And a GPS input which > I think is optional but desirable. > > The easiest thing may be to pick a unit and download their manual. The > ACK unit's manual is here: > http://www.ackavionics.com/406%20Page.html > > Good luck, > Bill Watson > > On 5/21/2012 10:53 AM, f.kyle@sympatico.ca wrote: >> Cheers, >> I have not yet chosen the model of ELT for inclusion on my Europa, >> but must make way for its eventual installation. That means fuse and wire >> size choice. >> Rather than spend time researching hesitant advertisers, I'm asking >> for your advice on the current requirement of your or any ELT. >> I am aware of the transmit level but of course it's for such a short time >> that there must be an average level plus safe margin with which to work. >> Thanks in advance. >> Ferg >> C-FFGG mono 914 CS prop >> > ________________________________ Message 6 _____________________________________ Time: 11:17:01 AM PST US From: rayj Subject: Re: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 I have no doubt he did it. I have done it to 1500v neon lighting transformers to see it they were hot. This does not address the "explanation" of how he did it. > I used to know an 85-year old electrician nicknamed Sparky (really) > who told me that in the early days they never used meters, he would > just put his two fingers across the line (even 440V!). But there was > a technique to it--one finger on the hot and one on the ground or > neutral AT THE SAME INSTANT--And don't touch anything else. Same when > removing them. Your claim that there is a technique to it, -----"AT THE SAME INSTANT"--------- is baseless, based on your explanation below. Which one is it???? Timing of the contact of the fingers has NOTHING to do with it and retelling stories with no basis in fact serves no purpose except to perpetuate falsehoods and whatever dangers are associated with believing them. Raymond Julian Kettle River, MN "And you know that I could have me a million more friends, and all I'd have to lose is my point of view." - John Prine On 05/22/2012 12:30 PM, Eric M. Jones wrote: > --> AeroElectric-List message posted by: "Eric M. > Jones" > > >> I'm skeptical. Raymond Julian > > > Raymond. It is important to note that the electrical current flowed > only up one finger and down the adjacent finger...never through the > body, the heart or any bundle of nerves. So it couldn't kill him. > > Sparky also had tough hands that had done hard work for decades....I > didn't doubt him at all. There are lots of seemingly-dangerous > electrical tricks...if you know what you're doing. At 440V and 25k > ohm dry skin, that's only 18 milliamps RMS. It shouldn't be a problem > at all. > > How about we both try it and report back. YOU FIRST! > > -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive > Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=373577#373577 > > ________________________________ Message 7 _____________________________________ Time: 11:32:31 AM PST US Subject: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 From: "Eric M. Jones" > Timing of the contact of the fingers has NOTHING to do with it and > retelling stories with no basis in fact serves no purpose except to > perpetuate falsehoods and whatever dangers are associated with believing them. > > Raymond Julian Man, Chill. That's what he said and I had no reason to disbelieve him. But yes, the two finger thing might not be useful. Chill!! -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=373583#373583 ________________________________ Message 8 _____________________________________ Time: 11:55:57 AM PST US From: "ROGER & JEAN CURTIS" Subject: RE: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 This does not address the "explanation" of how he did it. > I used to know an 85-year old electrician nicknamed Sparky (really) > who told me that in the early days they never used meters, he would > just put his two fingers across the line (even 440V!). But there was > a technique to it--one finger on the hot and one on the ground or > neutral AT THE SAME INSTANT--And don't touch anything else. Same when > removing them. Your claim that there is a technique to it, The part that is not well explained is that you must not be in contact with any ground. Now you can touch the hot wire and not be shocked, because there is not a completed circuit through your body. So, If you are not grounded it makes no difference if you touch both wires at the same time or not. There is only a completed circuit when you touch both wires, and the completed circuit is from one finger to the other. Hope this muddies the waters even more. Don't do this!! It's a stupid practice!!! Roger Do Not Archive ________________________________ Message 9 _____________________________________ Time: 11:55:58 AM PST US From: "jason@jasonbeaver.com" Subject: Re: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 When I first graduated from high school, I worked construction for one summer with an electrician who used the two finger trick to see if wires were hot. As long as no other portion of your body was grounded, you wouldn't get hurt. I spent most of the summer using this technique to see if wires were hot and learned to tell the difference between 110V and 220V feeds. At one point during the summer, I was helping him revive an old elevator from the late 1800s . At one point he touched two wires to see if they were hot and jerked his hand back in pain. He dug his multimeter out from the bottom of his toolbox and measure 600V DC on the wires! jason On May 22, 2012 at 1:30 PM "Eric M. Jones" wrote: > > > > I'm skeptical. Raymond Julian > > > Raymond. It is important to note that the electrical current flowed only up one finger and down the adjacent finger...never through the body, the heart or any bundle of nerves. So it couldn't kill him. > > Sparky also had tough hands that had done hard work for decades....I didn't doubt him at all. There are lots of seemingly-dangerous electrical tricks...if you know what you're doing. At 440V and 25k ohm dry skin, that's only 18 milliamps RMS. It shouldn't be a problem at all. > > How about we both try it and report back. YOU FIRST! > > -------- > Eric M. Jones > www.PerihelionDesign.com > 113 Brentwood Drive > Southbridge, MA 01550 > (508) 764-2072 > emjones(at)charter.net > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=373577#373577 > > ________________________________ Message 10 ____________________________________ Time: 11:56:12 AM PST US From: Bob McCallum Subject: RE: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 Eric is correct, can be done under the correct conditions. Not necessarily good idea, but possible. I found myself accidentally touching a live 600V 60 Hz wire once. Gets your attention real quick, but the connection was between a finger and the back of the same hand which was touching the junction box containing the live wire, no other ground involved. Very lucky but smarter! (In Canada most 3 phase industrial is 600 not 440 like the US) I'd turned off, and checked as dead, the main service to the building but this particular junction box was unfortunately back-fed from another building's service. I now check the individual circuits every time and not assume because the building is "dead" that every circuit also is. Another anecdotal example I personally witnessed was a mechanic, years ago, who tested the ignition wires on a running V8 auto engine to find a misfire by unplugging the wire from the spark plug, inserting a screwdriver, which he then held in his hand while resting against the block. He pronounced "that ones good" then proceeded to go to the next plug and so on until finally "there's the bad one". Impressed me no end, but not something I'm about to try myself. Do not archive Bob McC > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list- > server@matronics.com] On Behalf Of Eric M. Jones > Sent: Tuesday, May 22, 2012 1:30 PM > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 > > > > > I'm skeptical. Raymond Julian > > > Raymond. It is important to note that the electrical current flowed only up one finger > and down the adjacent finger...never through the body, the heart or any bundle of > nerves. So it couldn't kill him. > > Sparky also had tough hands that had done hard work for decades....I didn't doubt > him at all. There are lots of seemingly-dangerous electrical tricks...if you know what > you're doing. At 440V and 25k ohm dry skin, that's only 18 milliamps RMS. It > shouldn't be a problem at all. > > How about we both try it and report back. YOU FIRST! > > -------- > Eric M. Jones > www.PerihelionDesign.com > 113 Brentwood Drive > Southbridge, MA 01550 > (508) 764-2072 > emjones(at)charter.net > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=373577#373577 > > > > > > > > _- > ==================================================== > ====== > _- > ==================================================== > ====== > _- > ==================================================== > ====== > _- > ==================================================== > ====== > > ________________________________ Message 11 ____________________________________ Time: 12:28:35 PM PST US From: rayj Subject: Re: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 Chill..... that's your best response. Nuts. I was hoping to sort out fact from fiction. Never mind. Raymond Julian Kettle River, MN "And you know that I could have me a million more friends, and all I'd have to lose is my point of view." - John Prine On 05/22/2012 01:30 PM, Eric M. Jones wrote: > --> AeroElectric-List message posted by: "Eric M. Jones" > > >> Timing of the contact of the fingers has NOTHING to do with it and >> retelling stories with no basis in fact serves no purpose except to >> perpetuate falsehoods and whatever dangers are associated with believing them. >> >> Raymond Julian > > > Man, Chill. > > That's what he said and I had no reason to disbelieve him. But yes, the two finger thing might not be useful. > > Chill!! > > -------- > Eric M. Jones > www.PerihelionDesign.com > 113 Brentwood Drive > Southbridge, MA 01550 > (508) 764-2072 > emjones(at)charter.net > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=373583#373583 > > ________________________________ Message 12 ____________________________________ Time: 02:54:17 PM PST US From: Nikolaos Napoli Subject: Re: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 I have personally touched ignition wires in a high school electricity class many years ago with supervision from the instructor , after he demonstrated it first. As long as there is no other possible path other than the two fingers all you feel is a strong tingling in the fingers. Dont make a mistake though. Niko Nikolaos Napoli On May 22, 2012, at 2:55 PM, ROGER & JEAN CURTIS wrote: > > > This does not address the "explanation" of how he did it. > >> I used to know an 85-year old electrician nicknamed Sparky (really) >> who told me that in the early days they never used meters, he would >> just put his two fingers across the line (even 440V!). But there was >> a technique to it--one finger on the hot and one on the ground or >> neutral AT THE SAME INSTANT--And don't touch anything else. Same when >> removing them. > > Your claim that there is a technique to it, > > > > > The part that is not well explained is that you must not be in contact with > any ground. Now you can touch the hot wire and not be shocked, because > there is not a completed circuit through your body. So, If you are not > grounded it makes no difference if you touch both wires at the same time or > not. There is only a completed circuit when you touch both wires, and the > completed circuit is from one finger to the other. Hope this muddies the > waters even more. > > Don't do this!! It's a stupid practice!!! > > Roger > > Do Not Archive > > > > > > ________________________________ Message 13 ____________________________________ Time: 03:20:23 PM PST US Subject: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 From: "MikeDunlop" I can relate to some of these things, I started my working life as a mechanic and would like to have had a prize for every time I got zapped by touching the wrong end of a spark plug lead, 50k DC volts but no amps as such, one of the mechanics could stand there all day holding on to a live spark lead, I couldn't stand it... all it done was make me swear a lot though. On the other side of the coin, I had a friend who accidentally dropped a spanner across a 14k AC buss bar in a power station and received horrendous injuries including amputation of one arm. Moral of the story... know what you're dealing with and don't take chances. Miked (UK) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=373601#373601 ________________________________ Message 14 ____________________________________ Time: 05:34:54 PM PST US From: Henador Titzoff Subject: Re: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 Seems to me that all this voltage touchly-feely stuff is actually machismo at work. -Why not just use appropriate meters or tools to determine if >0 V is present? -This has the advantage of quantifying the voltage to a rea sonable level rather than counting the number of nads hairs standing up.=0A -=0AHenador Titzoff=0A=0A=0A________________________________=0A From: Mik eDunlop =0ATo: aeroelectric-list@matronics.com =0ASent: Tuesday, May 22, 2012 6:16 PM=0ASubject: AeroElectric-List: Re: AEC9001 Sc Dunlop" =0A=0AI can relate to some of these things, I s tarted my working life as a mechanic and would like to have had a prize for every time I got zapped by touching the wrong end of a spark plug lead, 50 k DC volts but no amps as such, one of the mechanics could stand there all day holding on to a live spark lead, I couldn't stand it... all it done was make me swear a lot though.- =0A=0AOn the other side of the coin,- I h ad a friend who accidentally dropped a spanner across a 14k AC buss bar in a power station and received horrendous injuries including amputation of on e arm.- - =0A=0AMoral of the story... know what you're dealing with and don't take chances.=0A=0AMiked (UK)=0A=0A=0A=0A=0ARead this topic online h ere:=0A=0Ahttp://forums.matronics.com/viewtopic.php?p=373601#373601=0A=0A = ________________________________ Message 15 ____________________________________ Time: 08:18:23 PM PST US From: "Jeff Luckey" Subject: RE: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 This thread should be renamed to "STUPID Electrician Tricks". _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Henador Titzoff Sent: Tuesday, May 22, 2012 17:33 Subject: Re: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 Seems to me that all this voltage touchly-feely stuff is actually machismo at work. Why not just use appropriate meters or tools to determine if >0V is present? This has the advantage of quantifying the voltage to a reasonable level rather than counting the number of nads hairs standing up. Henador Titzoff _____ From: MikeDunlop Sent: Tuesday, May 22, 2012 6:16 PM Subject: AeroElectric-List: Re: AEC9001 Schottky diode in Z-13/8 I can relate to some of these things, I started my working life as a mechanic and would like to have had a prize for every time I got zapped by touching the wrong end of a spark plug lead, 50k DC volts but no amps as such, one of the mechanics could stand there all day holding on to a live spark lead, I couldn't stand it... all it done was make me swear a lot though. On the other side of the coin, I had a friend who accidentally dropped a spanner across a 14k AC buss bar in a power station and received horrendous injuries including amputation of one arm. Moral of the story... know what you're dealing with and don't take chances. Miked (UK) Read this topic online here: http://forums.matronics.com/viewtopic.php?p=373601#373601http://www.matronic s.com/Navigator? - MATRONICS WEB FORUMS -< ======================= ________________________________ Message 16 ____________________________________ Time: 10:58:20 PM PST US From: Paul Millner Subject: AeroElectric-List: Feels like voltage to me Touching at the same time has nothing to do with the relative safety, or foolishness. of this approach. You could touch one finger, wait 30 seconds, and touch the second without any increase in risk, or for that matter, improvement in safety. In fact, going slower might just improve the safety slightly... but don't do this anyway! Paul On 5/22/2012 10:10 AM, rayj wrote: > > I really have to ask. Are you making the claim that in all the years > "Sparky" used his fingers, He NEVER had his fingertips touch at > different times? Assuming 60Hz, a difference in contact times of the > the fingertips of 1/30 of a second would allow more than enough time > for any affect that was going to take place between 1st and 2nd finger > contact. > > Never more than 1/30 of a second, ever. > > I'm skeptical. ________________________________ Message 17 ____________________________________ Time: 11:19:02 PM PST US From: Paul Millner Subject: Re: AeroElectric-List: Re: Anti Corrosive Zinc Paste Unfortunately, utility hiring policies don't always select for the brightest bulbs, excusing the pun... which sometimes can be quite a challenge for their sophisticated customers who labor mightily, at times, to convince them that, for instance, current *still* equals voltage times resistance, or similar advanced concepts. I once had to have days of meetings, and finally they had to fly their B+ student out from headquarters, to understand that it really was OK if we *gave* them a little power free from time to time to improve voltage regulation of their system in our neighborhood. Fortunately, he brightened (there's that pun again) and said, "Oh, I get it!" Revised contract language and relay settings were then only months of work process in coming. It's kind of like government, though... the cynic says you want your best minds being entrepreneurial... not running the bureaucracies like Hitler and Mussolini did... :-) Paul On 5/21/2012 4:06 PM, Henador Titzoff wrote: > Thanks, Eric, I appreciate your analytic approach to our problems, > with tests to determine validity. > > Today I went to AutoZone and bought some Permatex Dielectric Grease in > an 8 oz squeeze tube. It should last me for several years. > > Also, today I saw three local electric utility guys get out of a > Chevrolet souped up truck and start looking at one of their boxes. > Two of them seemed to know what they were doing, while one was > studying what I was doing, which was studying what they were doing. I > walked across the street and asked them what they were doing, and he > said that Engineering was looking at a switch box to see how it > functioned. I asked him what it was switching, and he said 12,000V. > I asked him how it got stepped down to 240V and 120V, and he said he > didn't know. He asked one of the other guys, and they started looking > around, finally spotting a box about two doors down. He said that box > was a step down transformer. I asked him if he knew what Penetrox or > No-Ox-ID was, and he said no and asked me what they were. I told him > they were pastes with zinc used to coat aluminum wires to keep them > from corroding, and he said he had heard of something like that. I'm > not sure where they dug up this fossil, but for an electric utility > engineer, he didn't know squat about his company's technology. I'm > now guessing he was a mismanager. > > Henador Titzoff > *From:* Eric M. Jones > *To:* aeroelectric-list@matronics.com > *Sent:* Monday, May 21, 2012 9:00 AM > *Subject:* AeroElectric-List: Re: Anti Corrosive Zinc Paste > > > > > I looked up Penetrox and there are several types; some for copper-to- > copper, some for aluminum-to-copper or aluminum-to-aluminum. > > Some history here is required: Years ago we experimented with > materials that contained suspended copper or silver for the purpose of > heat sinking large Xenon lamps, while simultaneously conducting > current (>20A). Here what happened: KA-BLAM-O!!! > > So we slinked back to using zinc oxide in silicone oil and no more > problem. Why we thought suspended metal particles was a good idea is > obvious...and wrong. > > What happened was that the suspended metal particles conducted current > while simultaneously preventing the really big flat contacts from > mating. And the current you can conduct with thousands of microscopic > particles is quite limited. > > So: Using goop with suspended metal particles is probably a good idea > at low current and modest voltage...like a connection to aluminum > antennae, or Al-Cu pigtails in homes wired with aluminum. But it's > probably a really bad idea with high currents at low voltages. Of > course this depends on the size of the particles, the materials and > hardness of the connectors and the pressure of the joint. > > But I wouldn't use the metal-particle goop without thinking about it > carefully. > > -------- > Eric M. Jones > www.PerihelionDesign.com > 113 Brentwood Drive > Southbridge, MA 01550 > (508) 764-2072 > emjones(at)charter.net > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=373466#373466 > http://www.matronics.com/Navigator? - MATRONICS WEB > FORUMS -< ======================= > > > * > > > * -- Please note my new email address! millner@me.com ------------------------------------------------------------------------------------- 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.