---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 11/06/07: 19 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 11:59 AM - Re: Questions on Z-16 Diagram (txpilot) 2. 12:20 PM - Battery Bus Feed (Richard Talbot) 3. 12:20 PM - TRIM Disconnect Switch () 4. 01:47 PM - Re: LR-3 Controller (dksington) 5. 02:57 PM - Re: TRIM Disconnect Switch (Dale Ensing) 6. 03:44 PM - Re: TRIM Disconnect Switch (Richard Dudley) 7. 04:02 PM - Re: TRIM Disconnect Switch (Dave Saylor) 8. 04:03 PM - 496 Audio--easy fix (Dave Saylor) 9. 04:36 PM - Re: TRIM Disconnect Switch (Kevin Horton) 10. 05:13 PM - Re: TRIM Disconnect Switch (Matt Prather) 11. 05:52 PM - Re: 496 Audio--easy fix (N81JG@aol.com) 12. 06:07 PM - Re: TRIM Disconnect Switch (Robert McCallum) 13. 07:24 PM - Hoping to garner interest for an aeroelectric seminar in the Southeast... (Don Hall) 14. 07:31 PM - Re: Hoping to garner interest for an aeroelectric seminar in the Southeast... (Neal George) 15. 07:39 PM - Re: Re: LR-3 Controller (Robert L. Nuckolls, III) 16. 07:41 PM - Re: TRIM Disconnect Switch (rtitsworth) 17. 07:41 PM - Re: Battery Bus Feed (Robert L. Nuckolls, III) 18. 07:43 PM - Re: TRIM Disconnect Switch (Robert L. Nuckolls, III) 19. 07:55 PM - Re: Re: Questions on Z-16 Diagram (Robert L. Nuckolls, III) ________________________________ Message 1 _____________________________________ Time: 11:59:45 AM PST US Subject: AeroElectric-List: Re: Questions on Z-16 Diagram From: "txpilot" > If you use some other ov protection > scheme, you could leave the breaker out and just > run the alternator field from a standard fuse > on the block. One choice would be using the AEC9011 > generator/alternator OV relay feature. This > eliminates the need for a breaker. Thanks, Bob. I'll just stick with the crowbar OV protection in the Z-16 diagram. I just ordered everything I need from B&C. Now all I need is a good fire extinguisher. [Laughing] Dan Read this topic online here: http://forums.matronics.com/viewtopic.php?p=144195#144195 ________________________________ Message 2 _____________________________________ Time: 12:20:13 PM PST US From: "Richard Talbot" Subject: AeroElectric-List: Battery Bus Feed Hi Everyone, One more question in relation to my Battery Bus. I am following Z-13 and adapting to my aircraft in a few places. One of these is in relation to the Battery Bus feed. I note that the drawing specifies a short run (6 inches or less) of 14 AWG wire from the positive side of the battery to the fuse block. My issue is that I am going to exceed the recommended wiring distance to around 3-4 feet and would feel more comfortable with some protection for the wire. As I see it my choices are: - Install an inline fuse holder in the engine compartment, near the battery. - Install a fusible Link. - Relocate the fuse block (I don't want to do this) I suspect the fusible link is a better option but I wanted to get some advice from other members of the list. If I use a fusible link how do I size it? Should it be 2AWG smaller than the wire? Thanks/Regards Richard ________________________________ Message 3 _____________________________________ Time: 12:20:14 PM PST US From: Subject: AeroElectric-List: TRIM Disconnect Switch G'day Everyone, First let me start this discussion with how I would install manual trim systems in my RV 7 next time. The servos, wiring, relays, stick grips and other associated issues are just not worth the trouble and cost IMO. However, I have the things now so I am going to finish putting them in. I am fairly unhappy having an electric trim system in my aircraft without any manual system as I believe it is at risk of running away and cannot be manually returned to an in trim position. My expectation is that it may be possible to catch it in the act and disable the trim system before it manages to get itself to full travel. I believe this is virtually a requirement in the certified world, and I have lost count of the number of aircraft I have flown over the years with electric trim disabled. I want the disconnect on the stick as I feel it may be difficult to find in a hurry if it is elsewhere. In order to alleviate this issue I propose to fit a "trim disconnect" switch to my Ray Allen G207 switch. To date I have the four momentary push buttons for trim, another button for PTT, another for AP disconnect and a spare momentary switch. I propose to use this for the Trim Disconnect. The momentary switch is not ideal, as I guess I am going to need to use it to trigger a CB to pop or similar. This adds expense for the cct breaker and the wires running to my stick grip are pretty small (around 24 AWG or smaller) so I am not sure it will work. My other option is to replace the momentary switch with a miniature toggle from Ray Allen rated at 2A. I could use this to switch the power supply to both motors. I can see this adds failure points. Has anyone satisfactorily done this previously? What is recommended in this area? Thanks/Regards Richard ________________________________ Message 4 _____________________________________ Time: 01:47:48 PM PST US Subject: AeroElectric-List: Re: LR-3 Controller From: "dksington" I have started wiring my aircraft and have wired a LR3-C controller as per instructions (whilst following Z-11). I have realised, though, that I have an internally regulated alternator (55A unit made by Air-Tec, supplied by Mattituck with my TMX IO-360). Can I 'double-up' on the regulator whilst maintaining the OV protection & LV indication or do I need to change something? Many thanks for the help in advance, and for the Aerolectric Connection - a truly excellent publication. Derek Sington. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=144219#144219 ________________________________ Message 5 _____________________________________ Time: 02:57:23 PM PST US From: "Dale Ensing" Subject: Re: AeroElectric-List: TRIM Disconnect Switch Richard, I have the miniature toggle switch for trim disconnect on my stick grip. Works fine other than occasionally hitting the switch unintentionally and turning off power to servo. Have Ray Allen trim servos on two homebuilt airplanes with no run away problems. Dale Ensing ----- Original Message ----- From: richard@talbots.net.au To: AeroElectric-List Digest Server Sent: Tuesday, November 06, 2007 3:18 PM Subject: AeroElectric-List: TRIM Disconnect Switch G'day Everyone, First let me start this discussion with how I would install manual trim systems in my RV 7 next time. The servos, wiring, relays, stick grips and other associated issues are just not worth the trouble and cost IMO. However, I have the things now so I am going to finish putting them in. I am fairly unhappy having an electric trim system in my aircraft without any manual system as I believe it is at risk of running away and cannot be manually returned to an in trim position. My expectation is that it may be possible to catch it in the act and disable the trim system before it manages to get itself to full travel. I believe this is virtually a requirement in the certified world, and I have lost count of the number of aircraft I have flown over the years with electric trim disabled. I want the disconnect on the stick as I feel it may be difficult to find in a hurry if it is elsewhere. In order to alleviate this issue I propose to fit a "trim disconnect" switch to my Ray Allen G207 switch. To date I have the four momentary push buttons for trim, another button for PTT, another for AP disconnect and a spare momentary switch. I propose to use this for the Trim Disconnect. The momentary switch is not ideal, as I guess I am going to need to use it to trigger a CB to pop or similar. This adds expense for the cct breaker and the wires running to my stick grip are pretty small (around 24 AWG or smaller) so I am not sure it will work. My other option is to replace the momentary switch with a miniature toggle from Ray Allen rated at 2A. I could use this to switch the power supply to both motors. I can see this adds failure points. Has anyone satisfactorily done this previously? What is recommended in this area? Thanks/Regards Richard ________________________________ Message 6 _____________________________________ Time: 03:44:29 PM PST US From: Richard Dudley Subject: Re: AeroElectric-List: TRIM Disconnect Switch Hi Richard, I resonate with your comments about the value of electric trim and switches on the stick grip. I had a couple of Cherokee 235s a couple of decades ago, one with a manual elevator trim by overhead crank, the other with electric elevator trim on the yoke. Both had manual flaps. When I flew the second one with the electric elevator trim, though it worked perfectly well, I found myself using the overhead manual crank for elevator trim. I never found the electric trim useful. The manual flaps were never a problem. When I built my RV-6A, I decided that I would go with manual elevator trim, manual aileron trim and manual flaps. Part of the rationale was the experience with the Cherokees and the rest was independence from the electrical system. At the time, I did not even think of runaway trim. Though I believe that runaway trim is a fairly remote failure in a simple system, I would now make it a consideration. The chance of detecting it in time to hit another switch before it went full throw seems poor. The real benefit of a trim access on the grip versus reaching for a manual trim knob doesn't strike me as worth the complications of multiple speed trim and concern about runaway and its solutions. I find my manual trim to allow delicate adjustment at all airspeeds. Perhaps, those who spend a lot of time at formation flying might find convenience with electric trim. However, in Navy flight training in SNJs in the 50s, we did a lot of formation flying with manual elevator and rudder trim without any related problems. I have a similar rationale for my manual flaps. They are not electrically dependent and are only used for landing and occasionally for takeoffs. My only switch on the stick grip is my push-to-talk. I consider that to be essential. I have read lots of e-mails on this list by folks who want to not only have push-to-talk and trim on the grip, but starter button and ident. That is a lot of stuff to wire, for parts count and reliability concerns. Best regards, Richard Dudley richard@talbots.net.au wrote: > G'day Everyone, > > > > First let me start this discussion with how I would install manual > trim systems in my RV 7 next time. The servos, wiring, relays, stick > grips and other associated issues are just not worth the trouble and > cost IMO. However, I have the things now so I am going to finish > putting them in. > > > > I am fairly unhappy having an electric trim system in my aircraft > without any manual system as I believe it is at risk of running away > and cannot be manually returned to an in trim position. My > expectation is that it may be possible to catch it in the act and > disable the trim system before it manages to get itself to full > travel. I believe this is virtually a requirement in the certified > world, and I have lost count of the number of aircraft I have flown > over the years with electric trim disabled. I want the disconnect on > the stick as I feel it may be difficult to find in a hurry if it is > elsewhere. > > > > In order to alleviate this issue I propose to fit a "trim disconnect" > switch to my Ray Allen G207 switch. To date I have the four momentary > push buttons for trim, another button for PTT, another for AP > disconnect and a spare momentary switch. I propose to use this for > the Trim Disconnect. > > > > The momentary switch is not ideal, as I guess I am going to need to > use it to trigger a CB to pop or similar. This adds expense for the > cct breaker and the wires running to my stick grip are pretty small > (around 24 AWG or smaller) so I am not sure it will work. > > > My other option is to replace the momentary switch with a miniature > toggle from Ray Allen rated at 2A. I could use this to switch the > power supply to both motors. I can see this adds failure points. > > > Has anyone satisfactorily done this previously? What is recommended > in this area? > > > Thanks/Regards > > Richard > > ________________________________ Message 7 _____________________________________ Time: 04:02:57 PM PST US From: "Dave Saylor" Subject: RE: AeroElectric-List: TRIM Disconnect Switch I usually recommend a master trim switch. On my plane I used a toggle CB between the flap switch and autopilot master. Another approach is to use a momentary pushbutton in the ground from the trim switch. Then it takes two fingers to activate trim, and runaway trim is pretty much eliminated since both switches would have to fail simultaneously. Dave Saylor AirCrafters LLC 140 Aviation Way Watsonville, CA 831-722-9141 831-750-0284 CL www.AirCraftersLLC.com _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Dale Ensing Sent: Tuesday, November 06, 2007 2:54 PM Subject: Re: AeroElectric-List: TRIM Disconnect Switch Richard, I have the miniature toggle switch for trim disconnect on my stick grip. Works fine other than occasionally hitting the switch unintentionally and turning off power to servo. Have Ray Allen trim servos on two homebuilt airplanes with no run away problems. Dale Ensing ----- Original Message ----- From: richard@talbots.net.au Server Sent: Tuesday, November 06, 2007 3:18 PM Subject: AeroElectric-List: TRIM Disconnect Switch G'day Everyone, First let me start this discussion with how I would install manual trim systems in my RV 7 next time. The servos, wiring, relays, stick grips and other associated issues are just not worth the trouble and cost IMO. However, I have the things now so I am going to finish putting them in. I am fairly unhappy having an electric trim system in my aircraft without any manual system as I believe it is at risk of running away and cannot be manually returned to an in trim position. My expectation is that it may be possible to catch it in the act and disable the trim system before it manages to get itself to full travel. I believe this is virtually a requirement in the certified world, and I have lost count of the number of aircraft I have flown over the years with electric trim disabled. I want the disconnect on the stick as I feel it may be difficult to find in a hurry if it is elsewhere. In order to alleviate this issue I propose to fit a "trim disconnect" switch to my Ray Allen G207 switch. To date I have the four momentary push buttons for trim, another button for PTT, another for AP disconnect and a spare momentary switch. I propose to use this for the Trim Disconnect. The momentary switch is not ideal, as I guess I am going to need to use it to trigger a CB to pop or similar. This adds expense for the cct breaker and the wires running to my stick grip are pretty small (around 24 AWG or smaller) so I am not sure it will work. My other option is to replace the momentary switch with a miniature toggle from Ray Allen rated at 2A. I could use this to switch the power supply to both motors. I can see this adds failure points. Has anyone satisfactorily done this previously? What is recommended in this area? Thanks/Regards Richard href="http://www.matronics.com/contribution">http://www.matronics.com/chref "http://www.matronics.com/Navigator?AeroElectric-List">http://www.matronics. com/Navigator?AeroElectric-List href="http://forums.matronics.com">http://forums.matronics.com ________________________________ Message 8 _____________________________________ Time: 04:03:32 PM PST US From: "Dave Saylor" Subject: AeroElectric-List: 496 Audio--easy fix We have the audio working as desired from the 496. It turned out to be a very simple solution. To recount: It was my intention to have terrain warnings from a Garmin 496 wired to the unswitched audio input of a Garmin GMA340 audio panel. Garmin sells a "power/data cable" that provides wiring for audio output along with serial data and 12VDC to power the GPS. The audio wires are labeled "voice+" and "voice-". Garmin also sells a similar cable that terminates in a speaker housed adjacent to a 12V plug for using in the car. I took the speaker housing apart and confirmed that the voice+/- wires connected to the speaker. When we ran the voice wires into the audio panel, we got nothing. We tried several approaches, including running the audio into DME (nothing), ADF (nothing), though an audio transformer, though a potentiometer and through various simple resistors (zip, zero, nada). Just dead air from the 496. Finally, Jacek Kesy, who works at AirCrafters, discovered that when the "voice-" wire from the GPS was disconnected from the audio panel, everything worked perfectly. Audio must be grounding somewhere else, and the wire that certainly seems like audio ground is actually "audio disable". Once the voice- wire is grounded, you have to turn the 496 off and back on to get any audio. Here is how the final scenario is wired: 1/8" audio jack is wired to Music 1 on the audio panel. It outputs warnings and XM audio. Music 1 is muted by intercom activity or incoming transmissions. As an aside, I also have a 1/8" audio jack wired through a toggle so I can select either XM or some other source for Music 1. But that has no bearing on the 496 audio problem. >From the 496 power/data cable, the "voice+" wire ties to a 220 ohm resistor, then to the unswitched audio input at the audio panel. The only other unswitched audio input is from the EFIS. It also goes through a 220 ohm resistor. Perhaps someone else can tell us what exactly the 220 ohm resistors do--my understanding is that they balance the two audio signals. I don't know what would happen without them. So now, even though the warnings coming from Music 1 are at time muted, I always get the EFIS warnings and the terrain warnings, as long as the audio panel is on. There are a bunch of setup parameters for the 496 as well on the Sound page of the main menu. Those are all pretty intuitive and seem to mostly effect the audio jack, not the output to the power/data cable. So that's it. Problem solved basically by trial and error, but it's working the way I want it to now. Dave Saylor AirCrafters LLC 140 Aviation Way Watsonville, CA 831-722-9141 831-750-0284 CL www.AirCraftersLLC.com ________________________________ Message 9 _____________________________________ Time: 04:36:57 PM PST US From: Kevin Horton Subject: Re: AeroElectric-List: TRIM Disconnect Switch On 6-Nov-07, at 3:18 PM, wrote: > I am fairly unhappy having an electric trim system in my aircraft > without any manual system as I believe it is at risk of running away > and cannot be manually returned to an in trim position. My > expectation is that it may be possible to catch it in the act and > disable the trim system before it manages to get itself to full > travel. I believe this is virtually a requirement in the certified > world, and I have lost count of the number of aircraft I have flown > over the years with electric trim disabled. I want the disconnect > on the stick as I feel it may be difficult to find in a hurry if it > is elsewhere. > > In order to alleviate this issue I propose to fit a trim > disconnect switch to my Ray Allen G207 switch. To date I have the > four momentary push buttons for trim, another button for PTT, > another for AP disconnect and a spare momentary switch. I propose > to use this for the Trim Disconnect. > > The momentary switch is not ideal, as I guess I am going to need to > use it to trigger a CB to pop or similar. This adds expense for the > cct breaker and the wires running to my stick grip are pretty small > (around 24 AWG or smaller) so I am not sure it will work. My RV-8 electric trim is wired through a master switch on the side console, and a momentary disconnect switch on the stick. The trim power is removed while the momentary switch on the stick is pressed. If I had a trim runaway, I would press and hold the trim disconnect switch on the stick, then turn off the master switch on the side console, then release the momentary switch on the stick. I also plan to do flight testing to check the stick forces with the trim at full travel in either direction. If the stick forces were too high, I would reduce the travel of the trim tab. -- Kevin Horton RV-8 (finishing kit) Ottawa, Canada http://www.kilohotel.com/rv8 ________________________________ Message 10 ____________________________________ Time: 05:13:17 PM PST US Subject: Re: AeroElectric-List: TRIM Disconnect Switch From: "Matt Prather" Does anyone use a visual or audible indicator for when the trim motor is running? A steady tone when the motor running wouldn't be too annoying, I think, and might make it easy to identify a problem. You could use a hall effect sensor to drive the indicator. I know it's counter to the goal of making systems simpler, but might be worth it for installations where a mechanical backup is impractical.. Matt- > > > On 6-Nov-07, at 3:18 PM, > wrote: > >> I am fairly unhappy having an electric trim system in my aircraft >> without any manual system as I believe it is at risk of running away >> and cannot be manually returned to an in trim position. My >> expectation is that it may be possible to catch it in the act and >> disable the trim system before it manages to get itself to full >> travel. I believe this is virtually a requirement in the certified >> world, and I have lost count of the number of aircraft I have flown >> over the years with electric trim disabled. I want the disconnect >> on the stick as I feel it may be difficult to find in a hurry if it >> is elsewhere. >> >> In order to alleviate this issue I propose to fit a trim >> disconnect switch to my Ray Allen G207 switch. To date I have the >> four momentary push buttons for trim, another button for PTT, >> another for AP disconnect and a spare momentary switch. I propose >> to use this for the Trim Disconnect. >> >> The momentary switch is not ideal, as I guess I am going to need to >> use it to trigger a CB to pop or similar. This adds expense for the >> cct breaker and the wires running to my stick grip are pretty small >> (around 24 AWG or smaller) so I am not sure it will work. > > My RV-8 electric trim is wired through a master switch on the side > console, and a momentary disconnect switch on the stick. The trim > power is removed while the momentary switch on the stick is pressed. > If I had a trim runaway, I would press and hold the trim disconnect > switch on the stick, then turn off the master switch on the side > console, then release the momentary switch on the stick. > > I also plan to do flight testing to check the stick forces with the > trim at full travel in either direction. If the stick forces were too > high, I would reduce the travel of the trim tab. > > -- > Kevin Horton RV-8 (finishing kit) > Ottawa, Canada > http://www.kilohotel.com/rv8 > > ________________________________ Message 11 ____________________________________ Time: 05:52:53 PM PST US From: N81JG@aol.com Subject: Re: AeroElectric-List: 496 Audio--easy fix HI Dave, I just got my RV7A panel all together and the XM antenna working. When I turned on the XM, radio and intercom ( I don't have an audio panel since I have only an SL30) I had the XM come on at high volume. I then noted that there was no volume control for the XM other than the intercom or headset controls. The GPS warning came through clear. I guess I will have to place a potentiometer in the GPS 1/8" output line to control the XM volume. Does anyone know how and where I get the right pot to do the volume control? I decided when I wired the Flightcom intercom and set the dip switches I didn't want the music to mute each time the radio or intercom squelch was broken so I will have to keep the music volume toned down so I will not miss any reception or warning. Oh, I guess the warnings will be toned down with the music. I'll have to see how that works. Mainly I want to be able to control XM music volume independent of the radio. John Greaves RV7A nearing completion VariEze N81JG nearing replacement of overhauled engine Redding, CA ________________________________ Message 12 ____________________________________ Time: 06:07:29 PM PST US From: "Robert McCallum" Subject: Re: AeroElectric-List: TRIM Disconnect Switch Trim runaway should hopefully be of minor concern for several reasons. 1; The likelihood of it happening is very low. (probably not worth worrying about) 2; Full trim travel in the types of aircraft we are building is generally liveable. i.e. although it may increase the stick forces somewhat the aircraft is still controllable (if it isn't then the trim effectiveness should perhaps be reduced until it is) 3; If you are really paranoid about the possibility, then it is a simple matter to install a DPDT centre off toggle switch in the wiring to the motor (after all the relays, control devices etc) so that in the event the trim does run away, the relays weld etc, you simply reverse this switch to run the trim back to neutral then select the centre off position to totally disconnect and isolate the motor. (this switch, if it becomes your choice, should be spring return to off from the reverse position to make it impossible to leave in the reverse position) 4; Manual trim eliminates even the remotest possibility if you're not otherwise comfortable. Bob McC ----- Original Message ----- From: "Matt Prather" Sent: Tuesday, November 06, 2007 8:12 PM Subject: Re: AeroElectric-List: TRIM Disconnect Switch > > Does anyone use a visual or audible indicator for when the trim motor is > running? A steady tone when the motor running wouldn't be too annoying, I > think, and might make it easy to identify a problem. You could use a hall > effect sensor to drive the indicator. I know it's counter to the goal of > making systems simpler, but might be worth it for installations where a > mechanical backup is impractical.. > > > Matt- > > > > > > > > On 6-Nov-07, at 3:18 PM, > > wrote: > > > >> I am fairly unhappy having an electric trim system in my aircraft > >> without any manual system as I believe it is at risk of running away > >> and cannot be manually returned to an in trim position. My > >> expectation is that it may be possible to catch it in the act and > >> disable the trim system before it manages to get itself to full > >> travel. I believe this is virtually a requirement in the certified > >> world, and I have lost count of the number of aircraft I have flown > >> over the years with electric trim disabled. I want the disconnect > >> on the stick as I feel it may be difficult to find in a hurry if it > >> is elsewhere. > >> > >> In order to alleviate this issue I propose to fit a "trim > >> disconnect" switch to my Ray Allen G207 switch. To date I have the > >> four momentary push buttons for trim, another button for PTT, > >> another for AP disconnect and a spare momentary switch. I propose > >> to use this for the Trim Disconnect. > >> > >> The momentary switch is not ideal, as I guess I am going to need to > >> use it to trigger a CB to pop or similar. This adds expense for the > >> cct breaker and the wires running to my stick grip are pretty small > >> (around 24 AWG or smaller) so I am not sure it will work. > > > > My RV-8 electric trim is wired through a master switch on the side > > console, and a momentary disconnect switch on the stick. The trim > > power is removed while the momentary switch on the stick is pressed. > > If I had a trim runaway, I would press and hold the trim disconnect > > switch on the stick, then turn off the master switch on the side > > console, then release the momentary switch on the stick. > > > > I also plan to do flight testing to check the stick forces with the > > trim at full travel in either direction. If the stick forces were too > > high, I would reduce the travel of the trim tab. > > > > -- > > Kevin Horton RV-8 (finishing kit) > > Ottawa, Canada > > http://www.kilohotel.com/rv8 > > > > > > > > > > > > > > > > > > > > > > > > ________________________________ Message 13 ____________________________________ Time: 07:24:26 PM PST US From: "Don Hall" Subject: AeroElectric-List: Hoping to garner interest for an aeroelectric seminar in the Southeast... I'm from Atlanta. Anywhere within reasonable driving distance is fine with me. Would try to secure a time somewhere in 1Q 2008. Please send me an email privately. If I can get enough folks interested, I'll contact Bob and secure a facility. Thanks, ****************************************** Don Hall N517DG (registered) rv7 finishing ****************************************** ________________________________ Message 14 ____________________________________ Time: 07:31:40 PM PST US From: "Neal George" Subject: RE: AeroElectric-List: Hoping to garner interest for an aeroelectric seminar in the Southeast... I'm in... Neal E. George 2023 Everglades Drive Navarre, FL 32566 Home - 850-515-0640 Cell - 850-218-4838 _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Don Hall Sent: Tuesday, November 06, 2007 9:23 PM Subject: AeroElectric-List: Hoping to garner interest for an aeroelectric seminar in the Southeast... I'm from Atlanta. Anywhere within reasonable driving distance is fine with me. Would try to secure a time somewhere in 1Q 2008. Please send me an email privately. If I can get enough folks interested, I'll contact Bob and secure a facility. Thanks, ****************************************** Don Hall N517DG (registered) rv7 finishing ****************************************** ________________________________ Message 15 ____________________________________ Time: 07:39:10 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: LR-3 Controller At 01:45 PM 11/6/2007 -0800, you wrote: > >I have started wiring my aircraft and have wired a LR3-C controller as per >instructions (whilst following Z-11). I have realised, though, that I >have an internally regulated alternator (55A unit made by Air-Tec, >supplied by Mattituck with my TMX IO-360). Can I 'double-up' on the >regulator whilst maintaining the OV protection & LV indication or do I >need to change something? No, the LR3 is not compatible with the internally regulated alternator. You can . . . (1) have the alternator modified to bring out the field lead for external regulation by means of the LR3C or . . . (2) wire per Z-24 as explained in . . . http://aeroelectric.com/articles/Adapting_IR_Alternators_to_Aircraft.pdf in anticipation of changing out for the AEC9004 Alternator Controller for IR alternators. >Many thanks for the help in advance, and for the Aerolectric Connection - >a truly excellent publication. Thank you for the kind words. I'm pleased that you find it a good return on investment. Bob . . . ---------------------------------------- ( "Problems are the price of progress. ) ( Don't bring me anything but trouble. ) ( Good news weakens me." ) ( -Charles F. Kettering- ) ---------------------------------------- ________________________________ Message 16 ____________________________________ Time: 07:41:28 PM PST US From: "rtitsworth" Subject: RE: AeroElectric-List: TRIM Disconnect Switch Richard, If you're referring to the typical Ray Allen (RAC) electric trim, you'll note that the only time there is power to the trim servo is when your wiring is commanding a trim movement. So, first off, it is virtually impossible for the servo itself to run-away. Rather, a "run-away" has to be caused by the up-stream wiring. Keep this in mind when designing and constructing your trim circuits. Also therefore, there are several potential approaches to mitigate potential run-away scenarios. 1. Limit the overall trim such that the plane is still manually controllable at full time. 2. Think about having two independent trim feeds/buttons (with isolated disconnects). One on each stick, or 1 stick and 1 panel, etc. That way, if one feed fails and causes a runaway, you can disconnect it and then take corrective action with the other. 3. Some folks have even put a momentary power feed line reversal circuit (button) in the system. Push it and whatever is causing the trim to run one way will automatically cause it to run back the other way. Let go (and disconnect) when it's in the middle (neutral). 4. etc The RAC system's safety is in it's inherent simplicity. From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of richard@talbots.net.au Sent: Tuesday, November 06, 2007 3:19 PM G'day Everyone, ..I am fairly unhappy having an electric trim system in my aircraft without any manual system as I believe it is at risk of running away and cannot be manually returned to an in trim position.. ________________________________ Message 17 ____________________________________ Time: 07:41:53 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Battery Bus Feed At 07:18 AM 11/7/2007 +1100, you wrote: >Hi Everyone, > > >One more question in relation to my Battery Bus. I am following Z-13 and >adapting to my aircraft in a few places. One of these is in relation to >the Battery Bus feed. I note that the drawing specifies a short run (6 >inches or less) of 14 AWG wire from the positive side of the battery to >the fuse block. My issue is that I am going to exceed the recommended >wiring distance to around 3-4 feet and would feel more comfortable with >some protection for the wire. As I see it my choices are: > > >- Install an inline fuse holder in the engine compartment, near the >battery. > >- Install a fusible Link. > >- Relocate the fuse block (I don t want to do this) If it's not next to the battery, then it's not a battery bus but an always-hot bus. There are reasons for the published recommendations based on about 70+ years of aviation experience. But it is your airplane and nobody here should be trying to convince you to do something that is not also supported by your understanding. > > >I suspect the fusible link is a better option but I wanted to get some >advice from other members of the list. > >If I use a fusible link how do I size it? Should it be 2AWG smaller than >the wire? Use a fuse here. It needs to be as responsive as practical to overload/fault conditions. Fuses are the device of choice. Bob . . . ---------------------------------------- ( "Problems are the price of progress. ) ( Don't bring me anything but trouble. ) ( Good news weakens me." ) ( -Charles F. Kettering- ) ---------------------------------------- ________________________________ Message 18 ____________________________________ Time: 07:43:15 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: TRIM Disconnect Switch At 07:18 AM 11/7/2007 +1100, you wrote: >G day Everyone, > > >First let me start this discussion with how I would install manual trim >systems in my RV 7 next time. The servos, wiring, relays, stick grips and >other associated issues are just not worth the trouble and cost >IMO. However, I have the things now so I am going to finish putting them in. > > >I am fairly unhappy having an electric trim system in my aircraft without >any manual system as I believe it is at risk of running away and cannot be >manually returned to an in trim position. My expectation is that it may >be possible to catch it in the act and disable the trim system before it >manages to get itself to full travel. I believe this is virtually a >requirement in the certified world, and I have lost count of the number of >aircraft I have flown over the years with electric trim disabled. I want >the disconnect on the stick as I feel it may be difficult to find in a >hurry if it is elsewhere. > > >In order to alleviate this issue I propose to fit a trim disconnect switch >to my Ray Allen G207 switch. To date I have the four momentary push >buttons for trim, another button for PTT, another for AP disconnect and a >spare momentary switch. I propose to use this for the Trim Disconnect. > > >The momentary switch is not ideal, as I guess I am going to need to use it >to trigger a CB to pop or similar. This adds expense for the cct breaker >and the wires running to my stick grip are pretty small (around 24 AWG or >smaller) so I am not sure it will work. > > >My other option is to replace the momentary switch with a miniature toggle >from Ray Allen rated at 2A. I could use this to switch the power supply >to both motors. I can see this adds failure points. > > >Has anyone satisfactorily done this previously? What is recommended in >this area? See: http://www.aeroelectric.com/PPS/Flight/Trim/AP_Disconnect_B.pdf Bob . . . ---------------------------------------- ( "Problems are the price of progress. ) ( Don't bring me anything but trouble. ) ( Good news weakens me." ) ( -Charles F. Kettering- ) ---------------------------------------- ________________________________ Message 19 ____________________________________ Time: 07:55:09 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Questions on Z-16 Diagram At 08:14 PM 11/5/2007 -0800, you wrote: > >Along these same Z-16 lines (Jabiru/Rotax with 20 amp AC generator)... > >Is it any problem for the regulator if it's control ("sense") is fed from >the same circuit breaker as the OV module ( and OV-relay coil)? > >In other words, if the OV relay trips (breaking the AC line between the >alternator and regulator), the "sense" line to the regulator opens, >dropping the control voltage into the regulator to zero. Is this a problem? > >Would there be any advantage (or disadvantage) to feeding the regulator >control directly from the bus? Depending on who's rectifier/regulator is being used, there may be manufacturer's prohibitions for connection of "C" to the bus independently of B and R. Having said that, and based on what I've seen of what's reputed to be an exemplar schematic of this genre' of rectifier/regulator, (See: http://www.aeroelectric.com/Pictures/Regulators/regul_912.jpg) I can perceive no reason in the physics for this prohibition. But unless provided with a lucid schematic of the specific device in question, I cannot refute the prohibition with confidence. Hence the drawing you see in Z-16. What problems have you deduced for wiring as suggested? Bob . . . ---------------------------------------- ( "Problems are the price of progress. ) ( Don't bring me anything but trouble. ) ( Good news weakens me." ) ( -Charles F. 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