---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 02/02/19: 9 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:05 AM - 555088-160 Air Jordan 1 Retro High OG Sail Red (blair2019) 2. 07:36 AM - Re: Overvoltage protection and other stuff (Robert L. Nuckolls, III) 3. 11:47 AM - Re: Overvoltage protection and other stuff (Alec Myers) 4. 03:52 PM - Re: Overvoltage protection and other stuff (Art Zemon) 5. 04:20 PM - Re: Overvoltage protection and other stuff (Alec Myers) 6. 05:01 PM - John Deere Generator pulses (Ernest Christley) 7. 05:31 PM - Narco Com-11 sidetone (N804RV) 8. 06:28 PM - Re: John Deere Generator pulses (user9253) 9. 09:59 PM - Re: Connectors (N804RV) ________________________________ Message 1 _____________________________________ Time: 04:05:40 AM PST US Subject: AeroElectric-List: 555088-160 Air Jordan 1 Retro High OG Sail Red From: "blair2019" It seems that this year's sneakers still can't escape the "Devil's Palm" of Air Jordan 1! Today, we just ushered in the release of the first Air Jordan 1 in 2019, and another new color scheme has surfaced! (https://www.2019mensjordans.com/product-category/air-jordan-1/)Air Jordan 1 Retro High OG Sail Red uses an extraordinarily vibrant white and red color. The white leather upper is complemented by red details and car lines. It also has a "two yuan" brush style! Flying wing logo, tongue embroidery label, this classic element is available, standard OG first year details. It will be officially released on March 16th, whether it is directly on the foot to cater to the bright sunshine in spring, or used for custom-made shoes, all of them are of good quality! Jordans 2019 Shoes (https://www.jordans2019shoes.com),Since the second half of last year, there have been a number of Foamposite foam materials to create the AF1 debut, and this time it is a high-top style! The Nike Air Force 1 Foamposite Cup NA Red is not only a unique bubble material, but also a dazzling all-red dress. Even the AF1 high-top shoe-shaped ankle straps are preserved. Although it is a pure red tone, the gloss effect of the upper and the matching of different materials still have a good visual level. In addition to the recent Tianjin spray theme, the Nike Sneakers (https://www.2019sneakersrelease.com/product-category/nike-sneakers/) brings us another surprise Nike Air Max 98, which is the white and red color. Similar to the Supreme sky-price co-branded style, this pair of Nike Air Max 98 is decorated with vibrant red in a white background. It is absolutely versatile and full of energy, making it easy to create a vibrant and energetic effect. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=487384#487384 ________________________________ Message 2 _____________________________________ Time: 07:36:57 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Overvoltage protection and other stuff At 03:43 PM 2/1/2019, you wrote: > >Bob et al. > >I=99m working with my engineering representative >to modify a TC aircraft to replace a 28V Gill >flooded battery with a pair of 12V Odyssey AGM in a different location. >The new location while not =9Csealed=9D, is not >provided with ventilation to the outside. > >Today=99s task is to demonstrate the new >installation will comply with 23.1353(d) which reads: >"No explosive or toxic gases emitted by any >battery in normal operation, or as the result of >any probable malfunction in the charging system >or battery installation, may accumulate in >hazardous quantities within the airplane.=9D There HAVE been H-O explosions associated with SVLA batteries. The only two I've been privy to were (1) an internal explosion on a 44AH bizjet battery that suffered an open, inter-cell weld in the top of the battery. The explosion cracked the case but did not cause damage to the aircraft. A second case was in a GlasAir fitted with a battery box behind the passenger seat. The battery contactor was inside the box too. The battery had been subjected to a sustained ov condition. The pilot was engaged in some exploratory, switch-flipping diagnostics that ignited the trapped gasses inside the battery box and blew it up. The WORST policy for dealing with an outgassing battery is to enclose it. The battery box was originally intended to conduct SPILLS over overboard. It had nothing to do with venting of gasses. The abused SLVA battery is LEAST likely to provoke a bad day in the cockpit by strapping it down to an open tray. Any dangerous gasses that do escape the battery simply waft away. Explosions occur when fuel is ignited within a tightly closed space. If 'fuel' is generated by an abused battery, the best prophylactic against explosion is to let it waft way. It won't explode or burn even if you ARE a smoker. >After conversation with Odyssey and after >reading their and other technical material I am >happy to argue that the only =9Cprobable=9D >malfunction in the charging system or battery >installation that could result in a release of a >hazardous quantity of gas would be a prolonged >over-voltage event (>30V for the two batteries >in series). That would release some quantity of hydrogen. Not the point. Proper conduct of FMEA considers ONLY one failure at a time. Assume that the battery WILL be abused as some point in the future. Then eliminate probability that the failure escalates into a more excited situation or propagation out to the rest of the system. Strap it down in the open air and you're good to go. >The aircraft charging system is based on a Bosch >28V automotive alternator; I don=99t have any >technical details of whether it has any inbuilt >over-voltage protection. The Approved Flight >Manual indicates that an over-voltage condition >has to be noticed by the pilot and pilot action >is required to take the alternator off-line >manually by pulling the c/b. So it=99s probable >there=99s no automatic protection included. > >To demonstrate that I=99m compliant with >23.1353(d) I=99m thinking of including in the >modification the installation of a crowbar >protection module on the alternator field coil. > >So=85 to get to the question=85 can anyone suggest a >part number/supplier for a 28V OV module (30V >trigger voltage)? Ideally one that is already in >use on a TC airplane somewhere, which will make >it easier to have that part approved as part of the modification. >. > >Or are there any other ways I could provide comfort with respect to 23.1353? Adding ov protection is called for by FMEA on the alternator irrespective of any other components on the aircraft. For decades, builders and some manufactures have modified internally regulated alternators to (1) remove internal regulators and (2) install legacy regulator/ov protection. I'll suggest that the confident fast-track is to do that mod to the alternator and install a regulator qualified for TC aircraft like https://tinyurl.com/yb6o5vtn or for OBAM aircraft https://tinyurl.com/y9tlkpyo Depending on your airplane's station in the aviation hierarchy. Both of these examples will come with OV protection . . . the B&C product also offers OV annunciation. Bob . . . ________________________________ Message 3 _____________________________________ Time: 11:47:25 AM PST US From: Alec Myers Subject: Re: AeroElectric-List: Overvoltage protection and other stuff > Strap it down in the open air and you're good to go. It is (they are) going to be located under the seat. The airframe is composite, and the seat frame is part of the airframe, forming a well, but the seat top doesnt seal tight, so lets assume that that the seat void is adequately ventilated for lighter-than-air gas to the rest of the cabin. Being a modern airframe, the cabin is relatively leak and draught free. The bubble canopy seals well with a rubber cushion all the way around. When the cabin ventilation system is shut off, there are no draughts. The lower explosive limit for Hydrogen is 4%. Taking a factor of 4 safety, and assuming a cabin volume of 3m^3, a hazardous amount of H2 is 30 litres. Outgassing from all lead acid batteries during a significant over voltage event is 7.6ml H2 / cell / amp / minute. RG technology works great to reduce outgassing at low charge rates but isnt a lot of use at high currents. The alternator is fitted with a 30A breaker. The worst case continuous release of hydrogen would occur when the alternator produces a voltage sufficient to charge the already-charged battery with a current of exactly 30A. Any more and the breaker will trip. There are 12 cells between the two batteries. That means that the worst case production of H2 is 2.7 litres / minute. A hazardous environment would follow, for regulatory purposes, in approximately 10-15 minutes, assuming no ventilation. I am *not* permitted to assume that the pilot will take the appropriate corrective action within that period and shut down the alternator. If I want to claim that the level of cabin ventilation is guaranteed to vent hydrogen at a rate sufficient to prevent buildup of 30l of H2 in that sort of time frame, I will have to justify that with adequate data. Alternatively if there is an over-voltage trip that prevents the bus voltage rising above 32V, then the battery would have to be limiting the overcharging current to less than 4A. The time to a hazardous buildup of H2 in the cabin would be 7.5 times greater, or more than one hour. At a current of 4A, I can carry out an experiment with the proposed battery and a power supply in the actual aircraft in a hangar, in still air conditions, to measure the cabin H2 concentration rate of rise. (I dont think I could find a power supply with sufficient voltage overhead to force 30A through a lead acid battery, nor would I feel comfortable doing so.) Another way to satisfy regulatory requirement is to use a Concorde RG-11M that has a manifold and a vent tube. I can connect the vent tube to the original vent provided for the flooded battery, and the requirement is satisfied because all gas will vent to the outside. The disadvantages are that its a lot more expensive than two odyssey batteries. And at 27lbs, harder to mount. >> I'll suggest that the confident fast-track is to do that mod to the alternator and install a regulator qualified for TC aircraft like There is merit in this idea, but I am concerned about project creep. To the extent that the existing IR alternator passed certification, its not an absolute requirement to upgrade it. On Feb 2, 2019, at 10:36 AM, Robert L. Nuckolls, III wrote: At 03:43 PM 2/1/2019, you wrote: > > Bob et al. > > Im working with my engineering representative to modify a TC aircraft to replace a 28V Gill flooded battery with a pair of 12V Odyssey AGM in a different location. > The new location while not sealed, is not provided with ventilation to the outside. > > Todays task is to demonstrate the new installation will comply with 23.1353(d) which reads: > "No explosive or toxic gases emitted by any battery in normal operation, or as the result of any probable malfunction in the charging system or battery installation, may accumulate in hazardous quantities within the airplane. There HAVE been H-O explosions associated with SVLA batteries. The only two I've been privy to were (1) an internal explosion on a 44AH bizjet battery that suffered an open, inter-cell weld in the top of the battery. The explosion cracked the case but did not cause damage to the aircraft. A second case was in a GlasAir fitted with a battery box behind the passenger seat. The battery contactor was inside the box too. The battery had been subjected to a sustained ov condition. The pilot was engaged in some exploratory, switch-flipping diagnostics that ignited the trapped gasses inside the battery box and blew it up. The WORST policy for dealing with an outgassing battery is to enclose it. The battery box was originally intended to conduct SPILLS over overboard. It had nothing to do with venting of gasses. The abused SLVA battery is LEAST likely to provoke a bad day in the cockpit by strapping it down to an open tray. Any dangerous gasses that do escape the battery simply waft away. Explosions occur when fuel is ignited within a tightly closed space. If 'fuel' is generated by an abused battery, the best prophylactic against explosion is to let it waft way. It won't explode or burn even if you ARE a smoker. > After conversation with Odyssey and after reading their and other technical material I am happy to argue that the only probable malfunction in the charging system or battery installation that could result in a release of a hazardous quantity of gas would be a prolonged over-voltage event (>30V for the two batteries in series). That would release some quantity of hydrogen. Not the point. Proper conduct of FMEA considers ONLY one failure at a time. Assume that the battery WILL be abused as some point in the future. Then eliminate probability that the failure escalates into a more excited situation or propagation out to the rest of the system. Strap it down in the open air and you're good to go. > The aircraft charging system is based on a Bosch 28V automotive alternator; I dont have any technical details of whether it has any inbuilt over-voltage protection. The Approved Flight Manual indicates that an over-voltage condition has to be noticed by the pilot and pilot action is required to take the alternator off-line manually by pulling the c/b. So its probable theres no automatic protection included. > > To demonstrate that Im compliant with 23.1353(d) Im thinking of including in the modification the installation of a crowbar protection module on the alternator field coil. > > So> to get to the question> can anyone suggest a part number/supplier for a 28V OV module (30V trigger voltage)? Ideally one that is already in use on a TC airplane somewhere, which will make it easier to have that part approved as part of the modification. > . > > Or are there any other ways I could provide comfort with respect to 23.1353? Adding ov protection is called for by FMEA on the alternator irrespective of any other components on the aircraft. For decades, builders and some manufactures have modified internally regulated alternators to (1) remove internal regulators and (2) install legacy regulator/ov protection. I'll suggest that the confident fast-track is to do that mod to the alternator and install a regulator qualified for TC aircraft like https://tinyurl.com/yb6o5vtn or for OBAM aircraft https://tinyurl.com/y9tlkpyo Depending on your airplane's station in the aviation hierarchy. Both of these examples will come with OV protection . . . the B&C product also offers OV annunciation. Bob . . . ________________________________ Message 4 _____________________________________ Time: 03:52:43 PM PST US From: Art Zemon Subject: Re: AeroElectric-List: Overvoltage protection and other stuff On Sat, Feb 2, 2019 at 2:04 PM Alec Myers wrote: > It is (they are) going to be located under the seat. The airframe is > composite, and the seat frame is part of the airframe, forming a well, bu t > the seat top doesn=99t seal tight, Alec, How about a low tech solution? Add a small vent from the well to the outside of the fuselage so that, whenever the airplane is in motion, low pressure on the outside draws air past the seat top, past the batteries, and out. -- Art Z. -- https://CheerfulCurmudgeon.com/ *"Be kind, for everyone you meet is fighting a hard battle."* ________________________________ Message 5 _____________________________________ Time: 04:20:11 PM PST US From: Alec Myers Subject: Re: AeroElectric-List: Overvoltage protection and other stuff I love low-tech! I dont think thats definitive enough for the powers that be, however. And I dont think my structures person will enjoy me drilling holes in a composite stressed fuselage just for a look see. On the subject of over-voltage trips, I have discovered that both Carling and Sensata (Klixon) make circuit breakers with, for instance, a second coil that you can use to trip the breaker via an isolated circuit (that could easily be triggered by an over-voltage, in addition to the regular over-current coil. So one of those could be used to replace the b-lead CB. It will be a challenge to find small quantities of what is a very specialized part though. On Feb 2, 2019, at 5:42 PM, Art Zemon wrote: On Sat, Feb 2, 2019 at 2:04 PM Alec Myers wrote: It is (they are) going to be located under the seat. The airframe is composite, and the seat frame is part of the airframe, forming a well, but the seat top doesnt seal tight, Alec, How about a low tech solution? Add a small vent from the well to the outside of the fuselage so that, whenever the airplane is in motion, low pressure on the outside draws air past the seat top, past the batteries, and out. -- Art Z. -- https://CheerfulCurmudgeon.com/ "Be kind, for everyone you meet is fighting a hard battle." ________________________________ Message 6 _____________________________________ Time: 05:01:18 PM PST US From: Ernest Christley Subject: AeroElectric-List: John Deere Generator pulses I'm using the pulses from my John Deere generator for my tack signal into m y EIS.=C2- Everything is working fine, and I've got a good solid signal. =C2- However, I'm not positive that I have it calibrated correctly.=C2- If someone with a JD generator that isn't mounted could tell me how many p ulses it makes for each revolution, I'd be very thankful. ________________________________ Message 7 _____________________________________ Time: 05:31:17 PM PST US Subject: AeroElectric-List: Narco Com-11 sidetone From: "N804RV" Anyone know if the Narco com-11 had sidetone? -------- Ken W. N804RV(reserved) RV-8 Empennage in work Read this topic online here: http://forums.matronics.com/viewtopic.php?p=487398#487398 ________________________________ Message 8 _____________________________________ Time: 06:28:57 PM PST US Subject: AeroElectric-List: Re: John Deere Generator pulses From: "user9253" What kind of engine? Is the generator gear driven or belt driven? How about using an optical tachometer to compare to the EIS? -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=487401#487401 ________________________________ Message 9 _____________________________________ Time: 09:59:59 PM PST US Subject: AeroElectric-List: Re: Connectors From: "N804RV" Here's what they are:https://youtu.be/XD1JDk1tCj4 This is the crimper you need to do it right: https://www.skygeek.com/dmc-tools-gmt232-commercial-crimp-tool-ad-1377.html?utm_source=googlebase&utm_medium=shoppingengine&utm_content=dmc-tools-gmt232-commercial-crimp-tool-ad-1377&utm_campaign=froogle&gclid=Cj0KCQiAnNXiBRCoARIsAJe_1cqpHgVAOlO0Ex-17snk3-lP0mvnmXVpE2YwSNUGU0P1KG_mrkt7ougaAgj7EALw_wcB -------- Ken W. 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