---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 01/31/04: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:47 AM - Re: Quick connects (KITFOXZ@aol.com) 2. 06:06 AM - ov protection for internal v.r. alternators (klehman@albedo.net) 3. 08:28 AM - Re: ov protection for internal v.r. alternators (Clay R) 4. 09:01 AM - Re: Alternator Field Wiring (John Schroeder) 5. 09:01 AM - Power supplies (Fergus Kyle) 6. 12:09 PM - Re: Re: ov protection for internal v.r. alternators (Ned Thomas) 7. 01:47 PM - Re: Quick connects (Robert L. Nuckolls, III) 8. 05:25 PM - Re: Quick connects (Dan Checkoway) ________________________________ Message 1 _____________________________________ Time: 05:47:25 AM PST US From: KITFOXZ@aol.com Subject: Re: AeroElectric-List: Quick connects --> AeroElectric-List message posted by: KITFOXZ@aol.com In a message dated 1/30/2004 3:01:52 AM Eastern Standard Time, dan@rvproject.com writes: All of the suggestions given are good ones. The problem with using a connector, though, is that if you need to remove the elevator, you'll have to remove the connector...not convenient. (at least that's the way it is on an RV...just a small round hole for the wire to pass through the elevator spar) Here's what I did instead: http://www.rvproject.com/20040124.html Hello Dan, As an electronics professional, hobbyist and aviation nut, it is good to see someone else finding some clever short cuts that I thought I owned in the privacy of my shop 8 ). Truthfully, many of us have used this "cheapest connector" idea for some years. But, it is more than just cheap as you have pointed out. It is a very small, reliable connection technique and if you stagger the connection pins a bit, there is no smaller total diameter method that I know of to connect a few wires in line for future easy disconnect. Another advantage is the ease in making the actual connections-one at a time in free space-not fighting to get to one pin in a nest of several. I also like "Dean's Connectors" as someone else mentioned. Dean's connectors are small, light, have very good contact pressures but they are a chore to solder the wires to if you are our age. (let's just say over 40) The Dean's connectors also suffer a diameter penalty in areas where that is an issue. Back to D-sub pins again, I have epoxied female pins just inside of small electronic goodies over the years. You drill a hole in the plastic shell of whatever device and cement the female pin inside. Cables of just a few wires with male pins connected and heat shrunk shielded are "plugged" in. Two holes in the side of a plastic cased goody backed up with female pins can be jumpered together with a "U" shaped pin where a function may be "jumpered" "out" or "in" for different functions. John P. Marzluf Columbus, Ohio Kitfox Outback (out back in the garage) ________________________________ Message 2 _____________________________________ Time: 06:06:30 AM PST US From: klehman@albedo.net Subject: AeroElectric-List: ov protection for internal v.r. alternators --> AeroElectric-List message posted by: klehman@albedo.net This is one of my remaining concerns as well. I'm using a different less common small alternator and the internal v.r. for it happens to be a bit expensive. I've seen several cautions regarding the requirement to have a battery in the circuit to stabilize alternators. If it is unstable, I can imagine excess voltage damaging the internal v.r. after the load is disconnected. That makes me think that a switch (Bat Master/Alt.) to allow disconnecting the ov relay while the engine is running may not be a good idea. Likewise my concern about ov protection unless I can be quite confident that no random erroneous disconnects are going to occur. A real ov event is not a concern of course as in that event the internal v.r. would almost certainly be already toasted. Ken >>>After talking to Vans, they said I probably blew the >>>voltage regulator by switching off the field that >>>disconnected the B-lead at the contactor. Switching >>>off field after it has started doesn't stop the >>>alternator because it gets field power from the >>>B-lead. They said they've been seeing this a lot >>>lately on alternators wired per z-24. >>> >>>Would it be an accurate statement to say that: >>>"Turning off the alt field after it has been turned on >>>for an internally regulated alternator wired as >>>depicted in Z-24 is a death sentence for the >>>alternator. An overvolt condition will also open the >>>contactor and finish off the alternator for good." >>> >>>If so, this might be a handy piece of information to >>>add to that diagram because it would have saved me >>>some trouble. > > This is the first I've heard of it. Gee, if Van's > has seen a rash of these events, it would have been > really nice of them to let me know about it. > > I'm looking into this. Watch this space. > > Bob . . . ________________________________ Message 3 _____________________________________ Time: 08:28:57 AM PST US From: Clay R Subject: AeroElectric-List: re: ov protection for internal v.r. alternators --> AeroElectric-List message posted by: Clay R Now I see the following warning on Vans web site on the alternator page. (I think this was added this week) Warning! The internally regulated 60 ampere alternator should not be used with overvoltage protection systems. If you open the charging circuit while it is in operation, it will destroy the regulator. -Clay __________________________________ ________________________________ Message 4 _____________________________________ Time: 09:01:17 AM PST US Subject: Re: AeroElectric-List: Alternator Field Wiring From: John Schroeder --> AeroElectric-List message posted by: John Schroeder Bob - 18 AWG and 22 AWGfuse link is it. Thanks John Do not archive > > If the wire between bus and regulator is long (say over > 6 feet) we'd like to minimize resistance . . . I'd > go 18/22 just for grins. Otherwise 20/24 is fine. > > Bob . . . ________________________________ Message 5 _____________________________________ Time: 09:01:54 AM PST US From: "Fergus Kyle" Subject: AeroElectric-List: Power supplies --> AeroElectric-List message posted by: "Fergus Kyle" Bob, " Unless your strobe supply has been sitting on the shelf for years, that time honored slow crank-up procedure isn't really useful. It was most useful 30 years ago before electrolytic capacitor technology really came of age . . ." Yeah, understood - 'cept the book that came with it says so, so maybe I've been harbouring this since '97. Of course as you have so clearly noted previously, manufacturers aren't ALWAYS right............. Cheers, Ferg ________________________________ Message 6 _____________________________________ Time: 12:09:06 PM PST US From: "Ned Thomas" <315@cox.net> Subject: Re: AeroElectric-List: re: ov protection for internal v.r. alternators --> AeroElectric-List message posted by: "Ned Thomas" <315@cox.net> For what it is worth, I had an internally regulated alternator on my RV6A. I had an Overvoltage occur and had no way to shut it off except land and turn off the engine. When I smelled the battery acid cooking out I was quite concerned. I was able to land before ruining the battery but even tho I immediately turned off the master when I found the voltmeter reading high, I did find that one of my strobes had fried. After this happened I installled the OV protection recommended by Bob. In the event you do encounter an OV situation you must be able to isolate the alternator. I was lucky, the battery could have blown up... ----- Original Message ----- From: "Clay R" Subject: AeroElectric-List: re: ov protection for internal v.r. alternators > --> AeroElectric-List message posted by: Clay R > > Now I see the following warning on Vans web site on > the alternator page. (I think this was added this > week) > > Warning! > The internally regulated 60 ampere alternator should > not be used with overvoltage protection systems. If > you open the charging circuit while it is in > operation, it will destroy the regulator. > > -Clay > > __________________________________ > > ________________________________ Message 7 _____________________________________ Time: 01:47:03 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Quick connects --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 08:46 AM 1/31/2004 -0500, you wrote: >--> AeroElectric-List message posted by: KITFOXZ@aol.com > >In a message dated 1/30/2004 3:01:52 AM Eastern Standard Time, >dan@rvproject.com writes: >All of the suggestions given are good ones. The problem with using a >connector, though, is that if you need to remove the elevator, you'll have >to remove the connector...not convenient. (at least that's the way it is on >an RV...just a small round hole for the wire to pass through the elevator >spar) > >Here's what I did instead: > >http://www.rvproject.com/20040124.html >Hello Dan, > >As an electronics professional, hobbyist and aviation nut, it is good to see >someone else finding some clever short cuts that I thought I owned in the >privacy of my shop 8 >). Truthfully, many of us have used this "cheapest >connector" idea for some years. But, it is more than just cheap as you >have pointed >out. It is a very small, reliable connection technique and if you stagger >the >connection pins a bit, there is no smaller total diameter method that I >know of >to connect a few wires in line for future easy disconnect. > >Another advantage is the ease in making the actual connections-one at a time >in free space-not fighting to get to one pin in a nest of several. I also >like "Dean's Connectors" as someone else mentioned. Dean's connectors are >small, >light, have very good contact pressures but they are a chore to solder the >wires to if you are our age. (let's just say over 40) The Dean's connectors >also suffer a diameter penalty in areas where that is an issue. > >Back to D-sub pins again, I have epoxied female pins just inside of small >electronic goodies over the years. You drill a hole in the plastic shell of >whatever device and cement the female pin inside. Cables of just a few >wires with >male pins connected and heat shrunk shielded are "plugged" in. Two holes in >the side of a plastic cased goody backed up with female pins can be jumpered >together with a "U" shaped pin where a function may be "jumpered" "out" or >"in" >for different functions. Just one caution. When examining connectors classically used in aircraft, one can see attention paid to protection of the pin-socket joints and making sure that tension on the wires won't open a joint. Unless you're working with butt-splices, knife splices, and soldered joints, etc. where resistance to tension are inherent in the technology, make sure your quest for miniaturization and/or convenience doesn't increased potential for failures that could make you uncomfortable. I offered the d-sub pins and heat shrink for compact thermocouple splicing . . . but then opening that joint in flight doesn't affect flight system performance. I don't intend to splash cold water on any innovative techniques . . . only a word to the wise to think through the failure mode effects analysis for any out-of-the-ordinary usage of parts. Question: do you KNOW how difficult it is to handle the airplane with a pitch trim actuator stuck at either extreme? Of course this question goes to reliability of ALL components in the pitch trim system, not just novel approaches to miniature connectors. Bob . . . ________________________________ Message 8 _____________________________________ Time: 05:25:07 PM PST US From: "Dan Checkoway" Subject: Re: AeroElectric-List: Quick connects --> AeroElectric-List message posted by: "Dan Checkoway" Thanks for the reality check. In answer to your question, I don't know for sure that the plane is manageable in a full out-of-trim condition. I've heard that RVs aren't a problem in that configuration (although not pleasant), and that's the assumption I'll run with until I have a chance to test it out first-hand in this particular plane. My feeling is that the D-subs-only approach is ok until the plane is painted. Once the elevators are finally reinstalled (essentially done being R&R'd come hell or high water), I think it makes sense at that point to use a D-9 connector (or something like it). I figure it would be painless to add the connector in the future since the pins and sockets are already wired. ;-) I guess my real point was that if you know ahead of time that the elevator needs to be removed, and you want to avoid cutting wires, the pins & sockets only approach is "convenient" (if not robust & foolproof). I don't mean to be defensive, and I really appreciate your point. I'm actually thinking that some sense of strain relief can be had by tie-wrapping the wires in an "S" (connectors in the middle of the S, so to speak) so that there can't be any direct tension on the pin/socket connections. I believe I have enough slack to do that. Anyway, thanks again, I'm just babbling, done now... 8-) do not archive )_( Dan RV-7 N714D http://www.rvproject.com ----- Original Message ----- From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Quick connects > --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > At 08:46 AM 1/31/2004 -0500, you wrote: > >--> AeroElectric-List message posted by: KITFOXZ@aol.com > > > >In a message dated 1/30/2004 3:01:52 AM Eastern Standard Time, > >dan@rvproject.com writes: > >All of the suggestions given are good ones. The problem with using a > >connector, though, is that if you need to remove the elevator, you'll have > >to remove the connector...not convenient. (at least that's the way it is on > >an RV...just a small round hole for the wire to pass through the elevator > >spar) > > > >Here's what I did instead: > > > >http://www.rvproject.com/20040124.html > >Hello Dan, > > > >As an electronics professional, hobbyist and aviation nut, it is good to see > >someone else finding some clever short cuts that I thought I owned in the > >privacy of my shop 8 > >). Truthfully, many of us have used this "cheapest > >connector" idea for some years. But, it is more than just cheap as you > >have pointed > >out. It is a very small, reliable connection technique and if you stagger > >the > >connection pins a bit, there is no smaller total diameter method that I > >know of > >to connect a few wires in line for future easy disconnect. > > > >Another advantage is the ease in making the actual connections-one at a time > >in free space-not fighting to get to one pin in a nest of several. I also > >like "Dean's Connectors" as someone else mentioned. Dean's connectors are > >small, > >light, have very good contact pressures but they are a chore to solder the > >wires to if you are our age. (let's just say over 40) The Dean's connectors > >also suffer a diameter penalty in areas where that is an issue. > > > >Back to D-sub pins again, I have epoxied female pins just inside of small > >electronic goodies over the years. You drill a hole in the plastic shell of > >whatever device and cement the female pin inside. Cables of just a few > >wires with > >male pins connected and heat shrunk shielded are "plugged" in. Two holes in > >the side of a plastic cased goody backed up with female pins can be jumpered > >together with a "U" shaped pin where a function may be "jumpered" "out" or > >"in" > >for different functions. > > Just one caution. When examining connectors classically > used in aircraft, one can see attention paid to protection > of the pin-socket joints and making sure that tension on > the wires won't open a joint. Unless you're working with > butt-splices, knife splices, and soldered joints, etc. where > resistance to tension are inherent in the technology, make > sure your quest for miniaturization and/or convenience doesn't > increased potential for failures that could make you > uncomfortable. I offered the d-sub pins and heat shrink > for compact thermocouple splicing . . . but then opening that > joint in flight doesn't affect flight system performance. > > I don't intend to splash cold water on any innovative > techniques . . . only a word to the wise to think through > the failure mode effects analysis for any out-of-the-ordinary > usage of parts. Question: do you KNOW how difficult it is > to handle the airplane with a pitch trim actuator stuck at > either extreme? Of course this question goes to reliability > of ALL components in the pitch trim system, not just novel > approaches to miniature connectors. > > Bob . . . > >