---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 06/17/08: 15 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:57 AM - Re: Lead-Free Solders (Jim McBurney) 2. 08:57 AM - Re: Lead-Free Solders (Robert L. Nuckolls, III) 3. 08:57 AM - Re: Broken Low Voltage Module (Robert L. Nuckolls, III) 4. 10:35 AM - Re: Broken Low Voltage Module (Bill Bradburry) 5. 11:03 AM - Thermocouple wire (Dennis Jones) 6. 11:18 AM - Slow make/break contacts (David E. Nelson) 7. 04:47 PM - Re: Slow make/break contacts (Robert L. Nuckolls, III) 8. 05:00 PM - Re: Thermocouple wire (Robert L. Nuckolls, III) 9. 05:14 PM - Re: Thermocouple wire (BobsV35B@aol.com) 10. 05:50 PM - Re: Thermocouple wire (Paul Kuntz) 11. 06:08 PM - Re: Thermocouple wire (ROGER & JEAN CURTIS) 12. 06:50 PM - Re: Thermocouple wire (Bob White) 13. 07:13 PM - Thermocouple wire (Dennis Jones) 14. 08:21 PM - Re: Thermocouple wire (Robert L. Nuckolls, III) 15. 08:27 PM - Re: Thermocouple wire (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 05:57:37 AM PST US From: "Jim McBurney" Subject: Re: AeroElectric-List: Lead-Free Solders I agree with you, Bob, that lead-free isn't the best way to go. However, it's getting harder and harder to get past the "tree-huggers". Notice how often you see "RoHS" in the catalogs anymore. Do not archive Blue skies and tailwinds Jim CH-801 DeltaHawk diesel Augusta GA 90% done, 90% left ________________________________ Message 2 _____________________________________ Time: 08:57:21 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Lead-Free Solders At 08:53 AM 6/17/2008 -0400, you wrote: > >I agree with you, Bob, that lead-free isn't the best way to go. However, >it's getting harder and harder to get past the "tree-huggers". Notice how >often you see "RoHS" in the catalogs anymore. > >Do not archive > >Blue skies and tailwinds Yes, but the RoHS components solder down very nicely with good ol' 63/37. I probably have a lifetime supply of the "good stuff" on my shelves. Now, this DOES raise the specter of tin-whiskers on components that are built to RoHS standards even when they're assembled to the product with 63/37. Fortunately, these experiences are rare. We've had hot tin dipped, closely spaced relay terminals on our GA aircraft for decades. 99.9% of the time, any whisker that might have offered a potential for system malfunction simply gets burned away. Of course, not the case with micro-electronics. In this case, it appears that conformal coatings have held the Whisker Dragon at bay. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 3 _____________________________________ Time: 08:57:47 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Broken Low Voltage Module At 10:54 PM 6/16/2008 -0400, you wrote: > > >Bob, >I sent the board in a couple of weeks ago. It should have been waiting for >you when you returned from your vacation to California. I never heard if >you found it ok. > >Have you had a chance to take a look at it, and if so, what did you >discover? > >Bill B It's laying on the desk right in front of me. I was thinking this morning that I could probably get to it this evening. I've been on travel quite a bit but there's a breathing spell coming up. Bob . . . ________________________________ Message 4 _____________________________________ Time: 10:35:37 AM PST US From: "Bill Bradburry" Subject: RE: AeroElectric-List: Broken Low Voltage Module Great! Thanks Bob! Bill B -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III Sent: Tuesday, June 17, 2008 11:55 AM Subject: Re: AeroElectric-List: Broken Low Voltage Module --> At 10:54 PM 6/16/2008 -0400, you wrote: > > >Bob, >I sent the board in a couple of weeks ago. It should have been waiting >for you when you returned from your vacation to California. I never >heard if you found it ok. > >Have you had a chance to take a look at it, and if so, what did you >discover? > >Bill B It's laying on the desk right in front of me. I was thinking this morning that I could probably get to it this evening. I've been on travel quite a bit but there's a breathing spell coming up. Bob . . . ________________________________ Message 5 _____________________________________ Time: 11:03:18 AM PST US From: "Dennis Jones" Subject: AeroElectric-List: Thermocouple wire What is the function of "serving thermocouple wire". Jonsey ________________________________ Message 6 _____________________________________ Time: 11:18:49 AM PST US From: "David E. Nelson" Subject: AeroElectric-List: Slow make/break contacts Hi Bob, While I was looking for the S700 series specs on Carling's www site, I came around a line of switches (F Series, in particular) with "slow make/break" contacts. This struck me as odd. Under what circumstances would one want to spread the contacts slowly? Thank you, /\/elson ~~ Lately my memory seems to be like a steel trap .... without any spring. ~~ ________________________________ Message 7 _____________________________________ Time: 04:47:10 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Slow make/break contacts At 01:15 PM 6/17/2008 -0500, you wrote: > > > >Hi Bob, > >While I was looking for the S700 series specs on Carling's www site, I >came around a line of switches (F Series, in particular) with "slow >make/break" contacts. This struck me as odd. Under what circumstances >would one want to spread the contacts slowly? It's not that you WANT to, it's an artifact of an inexpensive switch. You can buy switches with very fast contact spreading velocities and fast/forceful closing characteristics but these will use a mechanism that is much more complicated than: http://aeroelectric.com/Pictures/Switches/Carling_Cutaway.jpg While the el-cheeso switch does have an spring loaded, over-center action, it's still classed as a slow make-break device because you can "tease" it open and "sneak up" on a closure by holding the handle and preventing it from exploiting the over-center behavior. In a fast make/break device, you can't tease it. Once past the point of no return, the switch snaps to the new position with gusto. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 8 _____________________________________ Time: 05:00:09 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Thermocouple wire At 12:59 PM 6/17/2008 -0500, you wrote: >What is the function of "serving thermocouple wire". > >Jonsey Your use of the word "serving" doesn't bring up an image for me. I think I've heard the term used but its meaning escapes me at the moment. Bob . . . ________________________________ Message 9 _____________________________________ Time: 05:14:37 PM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: Thermocouple wire Hmmmm! When on a sailboat, "serving" something means we wrap it in a protective covering. Any possibilities there? Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 In a message dated 6/17/2008 7:02:11 P.M. Central Daylight Time, nuckolls.bob@cox.net writes: --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 12:59 PM 6/17/2008 -0500, you wrote: >What is the function of "serving thermocouple wire". > >Jonsey Your use of the word "serving" doesn't bring up an image for me. I think I've heard the term used but its meaning escapes me at the moment. Bob . . . **************Gas prices getting you down? Search AOL Autos for fuel-efficient used cars. (http://autos.aol.com/used?ncid=aolaut00050000000007) ________________________________ Message 10 ____________________________________ Time: 05:50:04 PM PST US From: "Paul Kuntz" Subject: Re: AeroElectric-List: Thermocouple wire That's what I was thinking -- in nautical use, serving means to wrap a large line with a smaller line or with cloth to protect it from chafing. So, when a wire is significantly longer than required, the excess is often folded back on itself a few times, then the end wrapped (served) around the folded portion to take up the extra length neatly. In the case of thermocouple wire, the application would be to get rid of the slack in the wire without having to cut it and thereby introduce additional dissimilar material junctions in the middle of the wire. Bob has talked many times about joining or splicing thermocouple wires so as not to influence the properties of its temperature detection ability, but I suspect the idea of "serving" the wire rather than remove the exess is another bit of electrical folklore that advises people to never cut and rejoin thermocouple cable. Cheers, Paul Kuntz On 6/17/08, BobsV35B@aol.com wrote: > > Hmmmm! > > When on a sailboat, "serving" something means we wrap it in a protective > covering. Any possibilities there? > > Happy Skies, > > Old Bob > AKA > Bob Siegfried > Ancient Aviator > 628 West 86th Street > Downers Grove, IL 60516 > 630 985-8502 > Stearman N3977A > Brookeridge Air Park LL22 > > In a message dated 6/17/2008 7:02:11 P.M. Central Daylight Time, > nuckolls.bob@cox.net writes: > > nuckolls.bob@cox.net> > > At 12:59 PM 6/17/2008 -0500, you wrote: > >What is the function of "serving thermocouple wire". > > > >Jonsey > > Your use of the word "serving" doesn't bring > up an image for me. I think I've heard the term > used but its meaning escapes me at the moment. > > Bob . . . > > > ------------------------------ > Gas prices getting you down? Search AOL Autos for fuel-efficient used cars > . > > * > > * > > ________________________________ Message 11 ____________________________________ Time: 06:08:51 PM PST US From: "ROGER & JEAN CURTIS" Subject: RE: AeroElectric-List: Thermocouple wire Hi Jonsey, Can you please restate your question and give us some reference context?? Roger -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Dennis Jones Sent: Tuesday, June 17, 2008 1:59 PM Subject: AeroElectric-List: Thermocouple wire What is the function of "serving thermocouple wire". Jonsey ________________________________ Message 12 ____________________________________ Time: 06:50:53 PM PST US From: Bob White Subject: Re: AeroElectric-List: Thermocouple wire On Tue, 17 Jun 2008 20:11:44 EDT BobsV35B@aol.com wrote: > Hmmmm! > > When on a sailboat, "serving" something means we wrap it in a protective > covering. Any possibilities there? > > Happy Skies, > > Old Bob > AKA > Bob Siegfried > Ancient Aviator > 628 West 86th Street > Downers Grove, IL 60516 > 630 985-8502 > Stearman N3977A > Brookeridge Air Park LL22 > > > In a message dated 6/17/2008 7:02:11 P.M. Central Daylight Time, > nuckolls.bob@cox.net writes: > > --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > > At 12:59 PM 6/17/2008 -0500, you wrote: > >What is the function of "serving thermocouple wire". > > > >Jonsey > > Your use of the word "serving" doesn't bring > up an image for me. I think I've heard the term > used but its meaning escapes me at the moment. > > Bob . . . > > > > > Interestingly enough, the only result from Google for "serving thermocouple wire" is to AC-21-99, Aircraft Wiring and Bonding Section 2 Chapter 16, Figure 16-14 shows the procedure and seems to match with the nautical terminology although I've don't recall hearing it before in reference to wiring. (http://www.casa.gov.au/rules/1998casr/021/021c99s2c16.pdf) Bob W. (Hanging on to the "bitter end".) Do not archive -- N93BD - Rotary Powered BD-4 - http://www.bob-white.com 3.8 Hours Total Time and holding Cables for your rotary installation - http://roblinstores.com/cables/ ________________________________ Message 13 ____________________________________ Time: 07:13:34 PM PST US From: "Dennis Jones" Subject: AeroElectric-List: Thermocouple wire I found a reference in AC 21-99 that states that the thermocouple wire is served at the branching point using nylon or waxed cotton cord in cool areas and fiberglass cord in hot areas. It also shows how to do the wrapping. It also references using clear lacquer at the flat base area covering 12.7 mm. The serving will prevent unraveling of the outer jacket. Jonsey ________________________________ Message 14 ____________________________________ Time: 08:21:54 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Thermocouple wire At 09:10 PM 6/17/2008 -0500, you wrote: >I found a reference in AC 21-99 that states that the thermocouple wire is >served at the branching point using nylon or waxed cotton cord in cool >areas and fiberglass cord in hot areas. It also shows how to do the >wrapping. It also references using clear lacquer at the flat base area >covering 12.7 mm. The serving will prevent unraveling of the outer jacket. > Aha! Yes, SOME thermocouple wires are covered in a woven fiberglas jacket and they will unravel with time and look funky. I have used the dacron flat lace to wrap the outer jacket and prevent fraying. You can use a short piece of heatshrink for this task too. As far as 'extra' wire, you can coil it up if you're loath to cut it. But I generally cut to finished length and put a connector on it. My favorite TC wires are the TT-K series from Omega found at: http://www.omega.com/ppt/pptsc.asp?ref=XC_K_TC_WIRE&Nav=temh06 Neoflon PFA (HighPerformance) 20 TT-K-20 Solid 20 TT-K-20S 7 x 28 22 TT-K-22S 7 x 30 24 TT-K-24 Solid 24 TT-K-24S 7 x 32 30 TT-K-30 Solid 36 TT-K-36 Solid 40 TT-K-40 Solid This is a Tefzel-like insulation that is easy to strip, reasonably robust and user friendly in the tiny (36 and 40AWG) wire sizes. This stuff won't unravel. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 15 ____________________________________ Time: 08:27:55 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Thermocouple wire > > >Interestingly enough, the only result from Google for "serving >thermocouple wire" is to AC-21-99, Aircraft Wiring and Bonding > >Section 2 Chapter 16, Figure 16-14 shows the procedure and seems to >match with the nautical terminology although I've don't recall hearing >it before in reference to wiring. >(http://www.casa.gov.au/rules/1998casr/021/021c99s2c16.pdf) > >Bob W. (Hanging on to the "bitter end".) Interesting. This is a rather dated document that touches on TC wiring techniques typical of 1930 to 1950 when self-powered TC temperature instruments were common. These tended to have large AWG wires of specific length that could not be altered without affecting calibration of the instrument. They also did not benefit from modern plastic insulations. Modern TC signal conditioners draw pico-amperes of Seebeck voltage, ANY gage wire of ANY length will produce satisfactory performance. Yeah kids, that's how our grandpas used to do it! Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ------------------------------------------------------------------------------------- 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.