---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Mon 09/02/13: 5 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:27 AM - OT- Smart Coupler II available (rd2@dejazzd.com) 2. 09:12 AM - Re: Low voltage indicator with dual alternators (Bill Watson) 3. 09:15 AM - Re: Over Voltage on Start Up (dbarnes) 4. 12:59 PM - Re: Question regarding AEC figure Z-11 (Robert L. Nuckolls, III) 5. 01:18 PM - Re: Broadcast Radio Bleedover on Transceiver (mike>bentley) ________________________________ Message 1 _____________________________________ Time: 07:27:14 AM PST US From: rd2@dejazzd.com Subject: AeroElectric-List: OT- Smart Coupler II available Hi all, While cleaning the hangar I found a box containing Smart Coupler II (NMEA-to-analog converter for handheld GPS to Autopilot coupling - see www.porcine.com/gps/sc/ham1.html). It was intended for a project that was never started (turned out to be an overkill). It is still in its shipping box, never soldered, manual included. The pdf manual can be downloaded here: ftp://ftp.porcine.com/SmartCoupler/scii_manual.pdf If anyone is interested, pls contact me offlist. Rumen do not archive ________________________________ Message 2 _____________________________________ Time: 09:12:34 AM PST US From: Bill Watson Subject: Re: AeroElectric-List: Low voltage indicator with dual alternators The Z-14, my kitchen sink, and operations with an interconnected dual bus redux: Bob, you said somewhere below: "As you have deduced, running them in parallel during normal operations has the potential for obscuring failure of one of the alternators." 'duh, yeah... During my 2nd annual condition inspection on my RV10 I found a fatigued ring terminal on my secondary alternator because I didn't leave enough slack in the 8AWG wire. The magnitude of movement between the hind end of the B&C 20amp pad mounted alternator and the firewall is probably as large as between any other part proximal to the firewall. It was still conducting but probably with high resistance. There were signs of shrink tube melting from heat. It may be the root cause of my charging problems which now includes a dead Odyssey 680 battery and the need to operate with both electrical buses interconnected. The good news is that your very robust Z-14 design just went on functioning at 100% for way too many hours while this guileless pilot flew on wondering what was going on while killing a battery and adding a TCW Intelligent Power Stabilizer. My first flight after replacing the lead and swapping batteries resulted in everything working as expected. My essential 'kitchen sink' will run 'forever' on one 2 year old PC680 battery. The engine starts effortlessly with the buses interconnected, and both buses have normal voltage indications during normal non-interconnected operations. Thanks for the help, insight, and the elegant Z-14. Bill "learning to maintain the plane, step by step" Watson On 7/8/2013 12:58 PM, Bill Watson wrote: > > > On 7/6/2013 9:31 AM, Robert L. Nuckolls, III wrote: >> >> >> >>> I have the same setup and that's how it works. That is, the low >>> voltage light simply monitors the voltage on the bus independent of >>> alternator operation. Given that, I've wondered how a failed >>> alternator would manifest itself. >> >> What architecture are we talking about? Z-12 or Z-14? >> With independent buses for each alternator, the two >> systems are normally operated with the cross-feed OPEN. >> Each LV montior will tell the condition of it's respective >> bus. > It's a Z-14 >> >> >>> - If failure was due to an overvoltage situation, the breaker would >>> pop. Since I normally fly with the 2 buses interconnected >> >> Not recommended. > I see what you mean. >> >>> I would expect the low voltage lights to remain off perhaps for the >>> remainder of the flight. If one did come on because bus voltage >>> dropped below the threshold, I would expect both to come on more or >>> less simultaneously as long as the buses were interconnected. The >>> only explicit indication of Alt failure would be the popped OV breaker. >> >> The design goals for Z-14 were two-fold. (1) >> being able to parallel batteries for engine >> cranking and (2) being able to share power between >> systems in the event of an alternator failure. >> >> As you have deduced, running them in parallel >> during normal operations has the potential for >> obscuring failure of one of the alternators. > My operational goals for the Z-14 included being able to run much of > the panel on one battery while still having a fully charged battery > for starting. The idea being that I wanted to be able to enter flight > plans and even check weather before engine start. That's worked out > well. I can connect the buses for starts if needed and that works > well as well. However, I normally start with the buses separated > because if I go parallel, the voltage drop causes my 3 MDFs to re-boot. >> >>> - Are there other modes of Alternator failure where there would be >>> no explicit indication of failure? I'm thinking that a snapped belt >>> would be an example. If loads and battery condition were such that >>> the interconnected bus voltage stayed above the low volt threshold, >>> there would be no explicit indication. Is that right? >> >> Yes. Another reason for running them independently >> of each other for normal flight ops. With the crossfeed >> closed, you have a Z-12 with dual batteries. Unless >> one alternator is configured for stand-by operation by >> incorporation of the appropriate regulator, then you >> have two alternators in a paralleled mode of operation >> controlled by regulators not designed for paralleling >> (current management) of the two alternators. >> > I'll be going back to running independent. I know what got me started > running with the buses interconnected but I lost track of what this > robust configuration is designed to do. > > Thanks Bob! > > > ----- > No virus found in this message. > Checked by AVG - www.avg.com > > ________________________________ Message 3 _____________________________________ Time: 09:15:24 AM PST US Subject: AeroElectric-List: Re: Over Voltage on Start Up From: "dbarnes" Starting at the battery a #2 cable goes to the inside of the fire wall to a plate with a field of spade connectors then through a 5/16 inch brass bolt to the engine side of the firewall to another field of spade connectors and also to one of the starter mounting bolts through a large braided cable. The regulator is on the engine side of the firewall and gets its ground from one of the spade connectors. Originally I had the sense line of the regulator hooked to a dedicated output from vertical power. In trying to solve this problem I moved it to the battery positive bolt on the firewall (through a small fuse). At first it seemed to solve the problem but the charging voltage was too low. When I adjusted higher I was back to the same problem. I am going to the hanger this pm and will try an alternate ground to the engine block and extend wires into the plane to measure the sense voltage and compare it to the vp displayed voltage. Thanks, Dan Barnes Read this topic online here: http://forums.matronics.com/viewtopic.php?p=407925#407925 ________________________________ Message 4 _____________________________________ Time: 12:59:56 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Re: Question regarding AEC figure Z-11 At 09:44 PM 9/1/2013, you wrote: >Hi Bob, > >Well, the last couple days I've been reconsidering what equipment is >truly necessary for continued operation to safe arrival at an >airport. I've revised my endurance bus list as follows: > > * GDU375 (G3X display unit and GPS nav), 0.6A typical, 1.1A max > * GSU25 (G3X ADHARS and magnetometer), 0.2A > * GEA24 (G3X engine information unit), 0.43A max > * GTX327 Transponder, 1.5A > * 2 x LED panel flood, less than.1A > * Radio, 7.5A max, .6A typical Rx, 3.0A typical Tx >Here's the rationale behind these choices. The G3X system is a >pretty low draw and contains my main nav and instrument indications >so I figured I might as well keep the whole thing online. The engine >instruments may not be absolutely necessary, but the eng instrument >LRU draws less than half and amp. The one I'm still debating is the >radio. It's the highest current consumer of the bunch, but really >only when transmitting. Figure I can have it on the e-bus and then >if things are real tight, just switch it off How long would you like to fly before things 'get tight'? What are your battery-only endurance goals? >. I can turn the main bus back on when it's time to land to access >the fuel pump and flap so I'll leave those off the e-bus. Of course, >the e-ign will be on the always hot battery bus. Okay, what's the cruising flight current draw on the ignition system? I get about 2.4A continuous draw with the e-bus list above. >Thanks for your help. I'm sure you're quite busy so I appreciate you >taking time to review my plan! No problem . . . it's what we do. What size battery is installed? Bob . . . ________________________________ Message 5 _____________________________________ Time: 01:18:38 PM PST US Subject: AeroElectric-List: Re: Broadcast Radio Bleedover on Transceiver From: "mike>bentley" Seems to be coming through from the headsets. It's not near as bad when I disconnect the co pilots headset. I wonder if an external ground to the intercom box would help. -------- Mike Bentley Joplin, MO N5498B Model 4-1200 (Flying) Jabiru 2200 Rotec Aerosport LCH Heads GT Prop Ellison EFS-2 Throttle Body Read this topic online here: http://forums.matronics.com/viewtopic.php?p=407935#407935 ------------------------------------------------------------------------------------- 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.