---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 02/25/14: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:22 AM - Linear Actuator Position (Owen Baker) 2. 07:28 AM - Re: Wiring for Aircraft With Dual Electronic Ignition (user9253) 3. 07:38 AM - Re: Wiring for Aircraft With Dual Electronic Ignition (user9253) 4. 07:45 AM - Re: noise problem on radio (Robert L. Nuckolls, III) 5. 09:23 AM - Re: noise problem on radio (Sacha) 6. 01:33 PM - Re: Linear Actuator Position (The Kuffels) 7. 07:37 PM - Re: Wiring for Aircraft With Dual Electronic Ignition (Bob McCallum) ________________________________ Message 1 _____________________________________ Time: 05:22:10 AM PST US From: "Owen Baker " Subject: AeroElectric-List: Linear Actuator Position 2/25/2014 Hello James Baldwin, Are you expecting this simple circuit to also include how to create an indicator or display? There are already indicators in existence that require only simple wire connections. 1) See here: http://www.firgelli.com/Uploads/Pos%20datasheet.pdf at this home page: http://www.firgelli.com/products.php 2) See here: http://www.rayallencompany.com/products/indsens.html with this wiring instruction: http://www.rayallencompany.com/RACmedia/instructionsRP3.pdf at this home page: http://www.rayallencompany.com/products/servos.html I think that any ohm differences between your actuator and the indicators can either be rather easily overcome with help from some electrical guru or just ignored with the indicator still working effectively. OC PS: What linear actuator are you using and for what purpose? I have a few spare actuators that may be of help. 'O C' Baker says "The best investment you can make is the effort to gather and understand information." ============== Time: 06:55:51 PM PST US Subject: AeroElectric-List: Linear Actuator Position From: James Baldwin <1james.baldwin@gmail.com> Hey Electronic Guys -- Does anybody have a schematic for a simple circuit to show the position of the wiper on a 10k potentiometer? The leads are at each end of the resistor and one additional one for the wiper. I was thinking of a few LEDs that would light up depending on position of the wiper. Or maybe something that would light up when the actuator was centered. I also have a GRT EFIS if that could be used instead if anyone knows how. Thank you for the help. ________________________________ Message 2 _____________________________________ Time: 07:28:54 AM PST US Subject: AeroElectric-List: Re: Wiring for Aircraft With Dual Electronic Ignition From: "user9253" There is no fuse to protect the battery and wires from an alternator short circuit. I assume that the LEDs have a built-in resistor. ELTs do not normally require aircraft power. Replace 10 amp contactor coil fuses with 3 amp. Contactor and relay coils need diodes to short out high induced voltages. Main buses are not normally fused. The 60 amp fuse is not big danger, but it costs money, has weight and is one more thing to go wrong. I see no reason to have two contactors in series to feed the emergency bus. In fact, it doubles that chances of losing power to the bus. It is good to feed the avionics bus in two places, but the 5 amp fuses might blow. A relay is not necessary to indicate a blown turn coordinator fuse. Just put the LED in parallel with the fuse. Or buy a fuse that glows when blown, available in 3 amp or larger. Van's Aircraft sells them. The diode will reduce charging voltage to the aux battery, not necessarily a problem. Schottky diodes drop less voltage. There is a long, unprotected, always-hot wire between the battery and the master switch. Instead, most aircraft switch the negative side of the master contactor. Many builders have tried to improve on Bob Nuckolls' electrical architecture, but few have succeeded. You are probably better off using one of his drawings, perhaps Z-10/8 without the dynamo circuit. http://www.aeroelectric.com/PPS/Adobe_Architecture_Pdfs/ or even one like this is much less complicated: http://forum.matronics.com/download.php?id=37766 Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=419325#419325 ________________________________ Message 3 _____________________________________ Time: 07:38:13 AM PST US Subject: AeroElectric-List: Re: Wiring for Aircraft With Dual Electronic Ignition From: "user9253" If the emergency bus is inadvertently turned on during engine cranking, avionics bus fuses will blow. As is, there is no brownout protection for the avionics bus during engine cranking. The aux battery could be used for that purpose. Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=419326#419326 ________________________________ Message 4 _____________________________________ Time: 07:45:01 AM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: noise problem on radio At 03:46 PM 2/22/2014, you wrote: > >Thank you Bob, >I went back and inspired by your comment about Mr. Clue, I carefully >observed the phenomenon without jumping to conclusions. It turns out the >interference only happens when the (Trio Avionics Pro Pilot) Autopilot is >ON, even if the engine is OFF. Good work! > Attached is a link to a video with sound > >The interference happens in the form of a RX signal on the radio. In other >words, whatever is happening is causing the COM radio to think it's >receiving a transmission, as is evidenced by the RX signal that's visible on >the GNS430 screen. Okay, it's perceived as a radiated signal that comes in through the antenna coax. Have you checked SWR on the comm antenna? If your shield ground is loose at the radio, it can open a pathway for conducting otherwise insignificant signals into the receiver. Is there an installation/wiring manual for the AP that can be downloaded from the 'net? Also, you could 'sniff' around with a handheld. I'd craft a couple of probes to put onto your hand-held's antenna jack. An e-field probe consisting of a dime-sized disk supported on about an inch off the back end of the BNC connector. Also an h-field probe consisting of two turns of wire about 3/4" diam connected across a BNC connection on 1" of twisted leads. Open the squelch on the hand held and move the attached probes over components and wiring of the a/p to see if you can identify the strongest manifestation of the noise. Bob . . . ________________________________ Message 5 _____________________________________ Time: 09:23:04 AM PST US From: "Sacha" Subject: RE: AeroElectric-List: noise problem on radio > Attached is a link to a video with sound > >The interference happens in the form of a RX signal on the radio. In >other words, whatever is happening is causing the COM radio to think >it's receiving a transmission, as is evidenced by the RX signal that's >visible on the GNS430 screen. Okay, it's perceived as a radiated signal that comes in through the antenna coax. Have you checked SWR on the comm antenna? No, I haven't. Is it worth getting my hands on an SWR meter? If your shield ground is loose at the radio, it can open a pathway for conducting otherwise insignificant signals into the receiver. You mean that the coax shield could not connected or improperly connected to the appropriate BNC terminal? I actually have the coax connected to a backplate connector to which the GNS430 connector slides into, so I guess there is extra potential there for them not to properly connect (e.g. if the radio is not properly slotted into the backplate connector). Is there an installation/wiring manual for the AP that can be downloaded from the 'net? http://www.trioavionics.com/Pro%20Pilot%20Manual%203.8.pdf Also, you could 'sniff' around with a handheld. I'd craft a couple of probes to put onto your hand-held's antenna jack. I sniffed around yesterday with the handheld and its regular antenna. What I noticed was that as soon as I switch on the Avionics and the handheld antenna is close to them, I hear a bunch of noise, but I guess that's normal. When I switch on the AP and move the handheld antenna close to the servo cables (that are shielded), I can hear a stronger kind of buzzing noise. I really have to be almost touching those shielded cables though in order to pick anything up. I didn't try putting the antenna close to the radio's COM coax connector though. An e-field probe consisting of a dime-sized disk supported on about an inch off the back end of the BNC connector. Also an h-field probe consisting of two turns of wire about 3/4" diam connected across a BNC connection on 1" of twisted leads. Do you have any pictures of how to build these? Is this http://www.emcesd.com/tt120100.htm the right idea? Open the squelch on the hand held and move the attached probes over components and wiring of the a/p to see if you can identify the strongest manifestation of the noise. Bob Thanks again for the suggestions! Regards Sacha ________________________________ Message 6 _____________________________________ Time: 01:33:51 PM PST US From: "The Kuffels" Subject: Re: AeroElectric-List: Linear Actuator Position James, << schematic for a simple circuit to show the position of the wiper on a 10k potentiometer >> At $20, the 10 segment Firgelli indicator mentioned by Owen Baker is hard to beat. It appears to be "smart" in the sense it measures absolute voltage, not voltage relative to the buss value. This means the 10k potentiometer needs to be fed with a constant voltage such as provided by an LM7805 IC regulator. If you insist on building a simpler display the attached 5-level indicator uses less than $5 in parts. Tom ________________________________ Message 7 _____________________________________ Time: 07:37:49 PM PST US From: Bob McCallum Subject: RE: AeroElectric-List: Wiring for Aircraft With Dual Electronic Ignition Justin; 1. The 10A fuse on the starter relay serves no purpose. 2. Closing the switch leading from the "emergency" buss to the Blue Mountain EFIS back feeds the whole avionics buss through the 5amp fuse. It will most certainly fail. (and if the avionics master is closed also back feeds the main buss) What you're trying to do requires a second diode coming from the avionics buss, not just the single diode you've shown. 3. The four circuits on the left of the "emergency" buss back feed the main buss, making it impossible to isolate and also most likely the fuses will fail as they are likely not large enough in combination to support the whole of the electrical load. Guaranteed to fail if you touch the "starter" switch with the master off. Each of these four circuits, similar to above, require two diodes each to achieve what you've attempted to accomplish. 4. The "master" switch should be switching the ground side of the master relay, not the "live". 5. I don't see any active "low voltage" warning, unless that is the function of the circuit you've labeled "alt fault"?? Does your regulator support low voltage notification?? Many "alternator failure" lights do not achieve this goal. 6. Does your ELT actually require aircraft power?? This is rather unusual. 7. Nothing should be an "emergency". The word should not be part of an electrical system. In Bob's terms when the alternator fails, you revert to the pre-thought-out "plan B" which may entail switching off the main buss and relying on the "Endurance" buss for minimal electrical loads to get you to your destination. It shouldn't constitute an "emergency". 8. "Pulling fuses" should not be part of your "plan B' scenario, but I see a note whereby you "pull in case of buss failure". Switches are more convenient. In a "properly designed" electrical system there is no need to have any fuses accessible in flight. Nothing individually should be "critical" and troubleshooting should be done after the flight is over, not in the air. 9. Suggest reading AeroElectric connection and studying some of the "Z" drawings as most of what you are trying to achieve is elegantly covered and will allow you to fly, in the case of most failures, until you exhaust your fuel supply. (assuming proper battery maintenance) 10. By all means re-invent the wheel if you wish, that's what "experimental" is all about, but understand what's been developed before and the reasons behind why it's been done the way it was, and then tweak to suit your unique requirements. 11. As for your question on solid state relays, be aware that they are very reliable as long as they are properly heatsinked and kept within their ratings. We use them at work and get fantastic reliability as long as we over rate them. When operating at their design limits there are some failures, both fail open and fail closed. We've found that if we load them in the 30% to 50% range they are close to perfect. (no failures) Their chief advantage is very limited power consumption to operate the relay itself, conserving an extra amp or two of load to add to your battery endurance. Heat is their enemy and that's the reason behind de-rating to ensure they stay cool. We always keep them under 50% current rating. 12. Keep asking, we'll help you sort it out to be head and shoulders better than spam cans and achieve the reliability you require. Bob McC _____ From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Justin Jones Sent: Monday, February 24, 2014 10:39 AM Subject: AeroElectric-List: Wiring for Aircraft With Dual Electronic Ignition I am fairly unexperienced and new at the experimental building hobby. I am building a Bushcaddy L164 and I am putting dual electronic ignition on it. I absolutely need this to work at all times since I am flying over non-forgiving terrain in Alaska. The new systems are very reliable and I am confident that with a redundant system (EIGN-4-2R through the company fly EFII ) I will be fine as long as I can supply power to the system. I have drawn up a schematic on how I plan to wire the system and wanted some input from some experts out there to see if I have done anything incorrectly. I have attached the diagram. I have also considered using solid state relays in the system. I would use them for all of the relays except the starter relay. Any thoughts on this? I have found solid state relays that are rated for all of my applications to include the Battery Master (rated at 300A continuous and 500A for 1 sec). Thank you for your time and consideration. Justin ------------------------------------------------------------------------------------- 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.