---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 10/29/05: 18 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:39 AM - Re: [Please Read] The Do Not Archive Flag and List Behavior... (Vern W.) 2. 06:26 AM - Re: Controlling IR ND Alternators (Ken) 3. 07:22 AM - New Product (Display Drivers and Display Power) (John Schroeder) 4. 08:13 AM - Re: Fatwire (Eric M. Jones) 5. 12:14 PM - Re: New Product (Display Drivers and Display Power) (rv-9a-online) 6. 12:50 PM - Re: Re: PMA/VR's (Robert L. Nuckolls, III) 7. 01:29 PM - Re: New Product (Display Drivers and Display Power) (John Schroeder) 8. 03:10 PM - Ipod Wiring (Tinne maha) 9. 03:54 PM - Re: Re: Hobbs meter wiring (Robert L. Nuckolls, III) 10. 03:57 PM - Master Relay Mount (Michael Ashura) 11. 04:11 PM - Re: Master Relay Mount (Robert L. Nuckolls, III) 12. 05:01 PM - Re: Master Relay Mount (gert) 13. 05:36 PM - Re: New Product (Display Drivers and Display Power) (Leo Corbalis) 14. 06:32 PM - Re: Ipod Wiring (Jim Baker) 15. 06:45 PM - Re: Ipod Wiring (Jim Baker) 16. 07:29 PM - Peanut Gyro and inverter for sale (Richard Riley) 17. 08:43 PM - Master Relay Mount (Michael Ashura) 18. 09:37 PM - Re: Master Relay Mount (DonVS) ________________________________ Message 1 _____________________________________ Time: 05:39:19 AM PST US From: "Vern W." Subject: Re: AeroElectric-List: [Please Read] The Do Not Archive Flag and List Behavior... --> AeroElectric-List message posted by: "Vern W." On 10/28/05, Matt Dralle wrote: > > --> AeroElectric-List message posted by: Matt Dralle dralle@matronics.com > > > * Composing a message that makes > one's point, yet doesn't offend isn't rocket science, and we are > quite capable of this level of respect for one another.* > > Well Matt, it's not the rocket science of understanding how to make a respectful reply that is the problem in the AeroElectric list, it's "Rocket Propelled Egos" that seems to keep this kind of nonsense going. I'm amazed that Bob just keeps plugging on and keeps his tone level while staying focused on the true purpose of the list. I don't know how he does it. Vern ________________________________ Message 2 _____________________________________ Time: 06:26:21 AM PST US From: Ken Subject: Re: AeroElectric-List: Controlling IR ND Alternators --> AeroElectric-List message posted by: Ken Do we know what Zeftronics uses for a B lead contactor? I couldn't find any mention in the archives. Ken >snip > >Hello Larry, I believe that this goal can be met by buying the 40 amp >alternator kit advertised here >http://www.niagaraairparts.com/ along with the Zeftronic OVP wiring and >equipment set up available by link from this web site. > >snip > ________________________________ Message 3 _____________________________________ Time: 07:22:52 AM PST US Subject: AeroElectric-List: New Product (Display Drivers and Display Power) From: "John Schroeder" --> AeroElectric-List message posted by: "John Schroeder" Does anyone have an opinion as to how this device might help solve some of the problems of lighting panels or other cockpit/cabin lighting with LED's? Would it make things more complex than they are now? ie. dropping resistors, series vs parallel strings of LED's, etc. Thanks, John Schroeder ==================================== Maxim Integrated Products (NASDAQ: MXIM) introduces the MAX6971/MAX6983 16-port and the MAX6970/MAX6980/MAX6981 8-port constant-current LED drivers. All these LED drivers feature a 25MHz, 4-wire, industry-standard SPI-compatible serial interface. The 16 or 8 open-drain, constant-current-sinking LED driver outputs are rated at 36V. Using a single external resistor with a 2% current matching between outputs and 6% matching between cascaded devices, each port can sink up to 55mA for all LEDs. They operate from a 3V to 5.5V supply and are specified for the -40C to +125C operating range. All the devices are designed to support standard lighting and signage applications. More: http://www.maxim-ic.com/view_press_release.cfm/release_id/1158 -- ________________________________ Message 4 _____________________________________ Time: 08:13:38 AM PST US From: "Eric M. Jones" Subject: AeroElectric-List: Re: Fatwire --> AeroElectric-List message posted by: "Eric M. Jones" Perihelion Design sells two basic CCA fatwires: http://www.periheliondesign.com/fatwires.htm Typically (there is no standard), insulated 4AWG copper battery cable is 3.02 ounces per foot. Super-4-CCA is 1.72 ounces per foot (57% the weight of copper )--so you will save 2.03 pounds with 25' of cable. The stranding is 7 X 21 X 23g The specification are on the website (on the installation sheet). But the electrical specs are a dead-nuts match to 4AWG copper. However, the Super-2-CCA is a little more complicated. The cable manufacturer overshot the mark by 14%. I don't know to this day where the error was--the 23AWG strands do grow very slightly larger on the spool, but then again, manufacturer was responsible for meeting the resistance numbers (and the weight was the dependent variable)--I just don't know. The result was that the CCA wire is lower in resistance than copper. In fact it is lower in resistance than 2AWG silver. Super-2-CCA turned out to be 0.134 milliOhms per foot and 3.08 ounces per foot. (as above--this is about the typical weight of 4AWG copper) You can compare this with 2AWG copper, 2AWG Copper=0.156 milliOhms per foot 2AWG Silver =0.146 milliOhms per foot Super-2-CCA =0.134 milliOhms per foot 1AWG Copper=0.124 milliOhms per foot There really is a lot of variation in weight per foot for copper cable because of the variety of insulations, so I have not listed them here, but you can make your own comparisons. If you use 1AWG, there is only an 8% increase in resistance and a 54% decrease in weight (apprx.). And 1AWG cable is very heavy stuff. If you use 2AWG, there is a 16% decrease in resistance and a 40% decrease in weight (apprx.). Not quite what my target was but still extremely nice. I have suggested to several builders that if they have a low internal resistance battery, good connections and an easy-starting engine (like a Subie), I estimate that Super-4-CCA would be entirely satisfactory with a rear mounted battery. As they say--this is experimental--but that's what I'm planning to do in my Glastar. Both cables, after long study on the subject, were insulated with a proprietary polyvinyl thermoplastic elastomer, or call it PVC. But the new PVC is not like the old stuff. This insulation has no bad habits. Just cut a piece off and burn it to see how it behaves. It is self-extinguishing and doesn't emit noxious smoke. Along with 105 DegC, cut resistance, non-cracking, fuel and oil resistant, and all the good stuff. So that's the whole story. If you do nothing else just read the http://www.periheliondesign.com/fatwires_files/Copper%20cables.pdf on my website. Hope this clears thing up. Regards, Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 (508) 764-2072 "...Beans for supper tonight, six o'clock. Navy beans cooked in Oklahoma ham... Got to eat 'em with a spoon, raw onions and cornbread; nothing else...." --Will Rogers ________________________________ Message 5 _____________________________________ Time: 12:14:45 PM PST US From: rv-9a-online Subject: Re: AeroElectric-List: New Product (Display Drivers and Display Power) --> AeroElectric-List message posted by: rv-9a-online Hi John: The interface to the Maxim devices uses an SPI port, which usually assumes the involvement of a microprocessor. This adds cost/complexity. In addition, I don't think the MAX devices can be dimmed, although there may be a way to do it by switching the reference resistor value. Finally, you also need a low voltage logic supply. All of this means that it would be part of a bigger system, but not particularly cost effective as a stand-alone device for simple LED lamps. I've developing new 8 and 12 channel LED annuciator panel controllers with integral 0.4" x 0.8" LEDs. One of the constraints that I usually put on the products I develop is to consider the long-term maintenance and servicability. This means using commonly available multi-sourced components, and avoiding software (microprocessors) if not absolutely required. Five or ten years from now, when a problem develops, it shoud be simple for a field tech to diagnose and replace a faulty component. This is a round about way of saying that in my opinion, sometimes a ballast resistor per LED or per group of LEDs is a low-tech, reliable, serviceable solution that should be considered. Good luck with your project, Vern Little www.vx-aviation.com John Schroeder wrote: >--> AeroElectric-List message posted by: "John Schroeder" > >Does anyone have an opinion as to how this device might help solve some of >the problems of lighting panels or other cockpit/cabin lighting with >LED's? Would it make things more complex than they are now? ie. dropping >resistors, series vs parallel strings of LED's, etc. > >Thanks, > >John Schroeder >==================================== >Maxim Integrated Products (NASDAQ: MXIM) introduces the >MAX6971/MAX6983 16-port and the MAX6970/MAX6980/MAX6981 8-port >constant-current LED drivers. All these LED drivers feature a >25MHz, 4-wire, industry-standard SPI-compatible serial interface. >The 16 or 8 open-drain, constant-current-sinking LED driver >outputs are rated at 36V. Using a single external resistor with a >2% current matching between outputs and 6% matching between >cascaded devices, each port can sink up to 55mA for all LEDs. >They operate from a 3V to 5.5V supply and are specified for the >-40C to +125C operating range. All the devices are >designed to support standard lighting and signage applications. > More: http://www.maxim-ic.com/view_press_release.cfm/release_id/1158 > > > > ________________________________ Message 6 _____________________________________ Time: 12:50:55 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: PMA/VR's --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 07:54 AM 10/28/2005 -0400, you wrote: >--> AeroElectric-List message posted by: "Rodney Dunham" > > >Bob, > >Great idea about the upcoming comic book. BTW, why do you call them comic >books??? LOTS of pictures . . . see typical document at: http://aeroelectric.com/articles/CrimpTools/crimptools.html >My planes both use PM alternators. Almost all the discussion is concerning >the other alternator type. I would appreciate a comic book on the PM >alternator and VR. You're certainly aware of this increasingly popular technology. The SD-8 alternator is the product that launched B&C many moons ago. At that time, anything more than 20A from a PM alternator was in the real-hard pile. Now we're seeing some pretty hefty machines in the consumer products market. >Some of my questions: >How many volts AC produced by the (Rotax 912/Jabiru 3300) alternator at >various RPM's? This is a WAG but I've heard numbers on the order of 20-30 VAC from the AC output windings on a Rotax 912 at cruise RPM. This seems reasonable for a 14V system. I expect you would measure values in this range on about every alternator of this type. > How can I measure this on mine? (Should I???) Certainly if it satisfies some level of curiosity . . . and after having gathered such data, I'm sure there are folks on the list who would appreciate it if you shared it. However, aside from wanting to understand the inner workings of the system, there's no compelling reason for the installer/ operator of these systems to make the effort. > How many amps AC produced by the alternator at various RPM's? I recall seeing charts in a Rotax 912 manual that cited available output current for available DC output current versus RPM. As I recall, one could expect the full 18A only at cruise RPM. This is the biggest limitation for PM alternators. The difficulties with rectifying AND regulating the output in devices capable of carrying these relatively large currents compels the designer NOT to have any excess capabilities. Specifically, the answer to your question is that the AC current flowing in the output windings of the altenrator will be on the same order as the DC ouput current after the AC is rectified. The wound field alternator can be throttled by controlling field current so the only electronics that MUST carry output current are simple diodes on heatsinks. It's easy to reign in a wound field alternator running at 10,000+ RPM on the front of a Lycoming. Being able to operate with pulley ratios that provide nice outputs at ramp/taxi RPMs is an endearing quality. With the current state of the technology offered in PM alternator regulators, that luxury is not offered. Hence, folks who design these machines into their projects must design operating procedures that are accommodating to the system's limited output at less that cruise RPM. I found a copy of the 912 Installation Manual in my archives. Here's a couple of screen shots from the book: http://www.aeroelectric.com/Pictures/Alternators/Rotax_Aux_Alternator.gif http://www.aeroelectric.com/Pictures/Alternators/Rotax_PM_Alternator_!.gif It's interesting that the performance differences between a PM alternator and a wound-field alternator are published in same document. Note that at ramp/taxi speeds, the wound field alternator offers more output than the PM alternator does in cruise! > How does the (Ducati) VR convert the AC to DC? Somewhere in my stack of stuff, I have a schematic furnished by Giles for a dissected Ducati regulator supplied with the Rotax engines. It was similar in principle to the B&C regulator for the SD-8. A pair of diodes and a pair of silicon controlled rectifiers are connected in the classic full-wave bridge rectifier. The SCR's are used to control the regulator's DC output with circuitry that delay's triggering of the device until some time AFTER the rise in each cycle of the alternator's AC output wave form. The later the trigger, the lower the output. Found it: See http://www.aeroelectric.com/Pictures/Regulators/Regul_01.jpg and http://www.aeroelectric.com/Pictures/Regulators/regul_912.jpg The "transistors" marked TP154E must me TRIACS. They're shown as NPN transistors . . . which wouldn't work. > What happens to the extera engerny after the BAT is charged? Unlike the earliest PM regulators found on small engines and motor cycles, the modern PM regulators are SERIES control devices that throttle pathway between the regulator and battery such that as demand for energy goes down, current from the alternator goes down too. In the earliest days of this technology, designers used SHUNT regulators to simply load the alternator and keep it's output voltage in check after system demands went down. This system caused the alternator to "work" at full output all the time and after the battery was charged, a lightly loaded system produced a very hot-running regulator . . . virtually all of the alternator's available output was tossed off as heat. > What are the failure modes? The most prominent failure mode in these systems is damaged rectifiers due largely to insufficient cooling. > How would I recognize impending failure? You won't have any external electrical indications. The regulator's case temperature would be too high due to poor installation/cooling. > How do I differentiate BAT from VR from ALT failure? The alternator is relatively bullet proof. Failed PM alternators will have burned windings. Batteries are easily tested using techniques described in other threads and involves the used of capacity testing techniques, load testing techniques all of which can be mitigated by preventative maintenance techniques calling for periodic replacement (every annual). This leaves the rectifier/regulator as the weakest link in the system. Failure of this device is easily recognized by (1) inability to maintain bus voltage within established bounds with known loads at cruise RPM. > Do I really need crowbar protection in a PM system? Your needs are a function of perception of risk. There are folks among us that are satisfied with advertised and observed failure rates of modern regulators such that they're comfortable not having independent monitor and control of the OV condition in alternators. IF the alternator in question can be quietly, gently, and easily controlled from an OFF to an ON state at any time and under any conditions, then the addition of OV monitor and control is low cost and very simply accomplished. Given that the risks of an OV condition are not zero for any regulator, I would include it in any system I designed. Your personal position should be developed from whatever sources of data you have reason to trust. > Could you design a "dream regulator" that B&C could fab and sell me??? Absolutely. All it takes is $time$. >I think I have gleaned most of the answers to the above questions but need >to put it all together in my mind. Remember, I'm not an engineer. As a >friend of mine says frequently with a big grin, you have to explain it to me >like I'm a DOCTOR!* > >*In other words, keep it SIMPLE! In lieu of an launching an immediate effort to publish a comic book that details this technology, I hope the foregoing is useful to you. I'll put a copy of this thread in my to-do pile and see if we can formalize the effort with better illustrations at some later date. bob . . . ________________________________ Message 7 _____________________________________ Time: 01:29:45 PM PST US Subject: Re: AeroElectric-List: New Product (Display Drivers and Display Power) From: "John Schroeder" --> AeroElectric-List message posted by: "John Schroeder" Hi Vern - Thanks for the info. I'll scratch that idea. We are almost built-out. Soo a new approach to LED's will have to wait for the next airplane ;-)) John On Sat, 29 Oct 2005 11:56:57 -0700, rv-9a-online wrote: > All of this means that it would be part of a bigger system, but not > particularly cost effective as a stand-alone device for simple LED lamps. ________________________________ Message 8 _____________________________________ Time: 03:10:43 PM PST US From: "Tinne maha" Subject: AeroElectric-List: Ipod Wiring --> AeroElectric-List message posted by: "Tinne maha" Hello List, I'm installing an Ipod mini as the music input for my intercom. All done except the Ipod charger, which is the subject of today's question. (I haven't found any help in the haystack of blogs or at the apple site, so hoping I can get a little help here) I refuse to install a cigarette lighter type receptacle into my aircraft.....don't ask me why. The back of my Ipod mini says input current is 5-30 V DC, 1.0 amp max. This implies to me that I can runt the red wire on my adapter to a 1.0 amp fuse & the black wire straight to ground. I hope it is truly that simple. I would have already done this except the charger I got at the Ipod store (purchased mainly for the adapter) has a 2.0 amp fuse & a small cirquit board that drops the voltage to ~5.0 Volts (as measured by me.) I tried mounting & re-soldering the cirquit board into my set up but fried the cirquit board in the process not having a clue what I was doing. Now I'm afraid to just run 12 volts straight to my Ipod (even though the back implies it would be okay) Any comments or suggestions will be appreciated. Thanks in advance, Grant Krueger PS: Please don't tell me to install a cigarette lighter. The people behind the counter at the Ipod store or Radio Shack don't know & I can't find the info on any web site. I can't find contact info for apple without dropping $60 for a 2 year agreement. Frustrating. ________________________________ Message 9 _____________________________________ Time: 03:54:54 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Hobbs meter wiring --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > >Bob Hi! > >I'm using a device called Power Genie to supply start and stop Voltage to >Hobbs Meter. About to start my Rotax Engine. OK? > >Find it at: > >_http://www.powergenie.central5.com/_ (http://www.powergenie.central5.com/) Can't tell you anything about what goes on inside that product. If it were my airplane, I think I'd go this route: http://www.aeroelectric.com/PPS/Engine/HourMeter/Rotax_HourMeter_Adapter.pdf Bob . . . ________________________________ Message 10 ____________________________________ Time: 03:57:07 PM PST US From: "Michael Ashura" Subject: AeroElectric-List: Master Relay Mount --> AeroElectric-List message posted by: "Michael Ashura" I also have the plastic booties on my S701-1 that I bought from B&C. Mike ________________________________ Message 11 ____________________________________ Time: 04:11:50 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Master Relay Mount --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 03:53 PM 10/29/2005 -0700, you wrote: >--> AeroElectric-List message posted by: "Michael Ashura" > > >I also have the plastic booties on my S701-1 that I bought from B&C. > >Mike Are you talking about booties for the WIRE CONNECTIONS or for the MOUNTING FEET. I belive the original poster was telling us about plastic insulators on the contactor's mounting feet. Bob . . . ________________________________ Message 12 ____________________________________ Time: 05:01:27 PM PST US From: gert Subject: Re: AeroElectric-List: Master Relay Mount --> AeroElectric-List message posted by: gert i too have the black boots on the last master relay i bought from B&C. they are on the mounting brackets/feet. the brackets/feet that mounts the relay to the airframe, firewall etc. Robert L. Nuckolls, III wrote: >--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > >At 03:53 PM 10/29/2005 -0700, you wrote: > > > >>--> AeroElectric-List message posted by: "Michael Ashura" >> >> >>I also have the plastic booties on my S701-1 that I bought from B&C. >> >>Mike >> >> > > Are you talking about booties for the WIRE CONNECTIONS or > for the MOUNTING FEET. > > I belive the original poster was telling us about plastic > insulators on the contactor's mounting feet. > > Bob . . . > > > > -- is subject to a download and archival fee in the amount of $500 ________________________________ Message 13 ____________________________________ Time: 05:36:10 PM PST US From: "Leo Corbalis" Subject: Re: AeroElectric-List: New Product (Display Drivers and Display Power) --> AeroElectric-List message posted by: "Leo Corbalis" I don't want to toot my own horn but I wrote anarticle for Kitplanes, Mar. 2001 pg 64 that explains how to use a 555 timer ic for a light dimmer. It runs t about 1000 pulses per second and puts no noise on the bus with only the radio running (builtin intercom). I have 2 switching power supplies I built from kits for RC models that are about 50 years old that I potted in 5 minute epoxy and they both still work. Do a good job soldring and potting and you will be set for life. Make a boo boo and you get to make a new one. (1 guess) Leo Corbalis ----- Original Message ----- From: "John Schroeder" Subject: Re: AeroElectric-List: New Product (Display Drivers and Display Power) > --> AeroElectric-List message posted by: "John Schroeder" > > > Hi Vern - > > Thanks for the info. I'll scratch that idea. We are almost built-out. Soo > a new approach to LED's will have to wait for the next airplane ;-)) > > John > > > On Sat, 29 Oct 2005 11:56:57 -0700, rv-9a-online > wrote: > >> All of this means that it would be part of a bigger system, but not >> particularly cost effective as a stand-alone device for simple LED lamps. > > > ________________________________ Message 14 ____________________________________ Time: 06:32:53 PM PST US From: "Jim Baker" Subject: Re: AeroElectric-List: Ipod Wiring --> AeroElectric-List message posted by: "Jim Baker" > I'm installing an Ipod mini as the music input for my intercom. All > done except the Ipod charger, which is the subject of today's > question. Check out http://ipod.hackaday.com/entry/1234000270029372/ Should be able to power and charge thru the USB port as well. Search for LM78xx on Google, where xx is the desired output voltage, and a bit of wiring and soldering...instant power supply. Really easy to do. Whole power supply will run around a $1 to $2, tops. Also http://www.fairchildsemi.com/ds/LM/LM7805.pdf for data sheet and application notes. Jim Baker 580.788.2779 '71 SV, 492TC Elmore City, OK ________________________________ Message 15 ____________________________________ Time: 06:45:08 PM PST US From: "Jim Baker" Subject: Re: AeroElectric-List: Ipod Wiring --> AeroElectric-List message posted by: "Jim Baker" > > I'm installing an Ipod mini as the music input for my intercom. All > > done except the Ipod charger, which is the subject of today's > > question. Forgot to mention...the input voltage for this type of device is always 2 to 3 volts above the rated/desired output voltage....that is, I wouldn't use an LM7812 in a nominally 12 volt system. For your application I'd use a LM7809 or lower.... Jim Baker 580.788.2779 '71 SV, 492TC Elmore City, OK ________________________________ Message 16 ____________________________________ Time: 07:29:26 PM PST US From: Richard Riley Subject: AeroElectric-List: Peanut Gyro and inverter for sale --> AeroElectric-List message posted by: Richard Riley I have a JET 2.25" gyro for sale. It's ex-military, 110v 3 phase 400 hz, but I'm including a 12v DC inverter to run it. I was told it was freshly overhauled when I bought it but it doesn't have yellow tags. It's been spun up every 30 days since I bought it, 4 years ago. $1000 -- ________________________________ Message 17 ____________________________________ Time: 08:43:52 PM PST US From: "Michael Ashura" Subject: AeroElectric-List: Master Relay Mount --> AeroElectric-List message posted by: "Michael Ashura" The plastic boots are on the mounting flanges (tabs, legs) that attach the B&C contactor to the firewall. Mike ________________________________ Message 18 ____________________________________ Time: 09:37:22 PM PST US From: "DonVS" Subject: RE: AeroElectric-List: Master Relay Mount --> AeroElectric-List message posted by: "DonVS" The picture of the S701=1 on the B&C web site does not show the "boots" on the mounting feet. I ordered mine about three monthe ago and it also came with the boots. Do Not Archive -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Michael Ashura Subject: AeroElectric-List: Master Relay Mount --> AeroElectric-List message posted by: "Michael Ashura" The plastic boots are on the mounting flanges (tabs, legs) that attach the B&C contactor to the firewall. Mike