---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sun 05/03/09: 13 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:22 AM - Re: Fried EXP2BUS was EXP2BUS and non-functioning alternator (Vincent Himsl) 2. 11:40 AM - System Off Current Requirements... (Matt Dralle) 3. 12:18 PM - Re: System Off Current Requirements... (Robert L. Nuckolls, III) 4. 01:08 PM - Re: System Off Current Requirements... (Ernest Christley) 5. 01:42 PM - Re: System Off Current Requirements... (Charlie England) 6. 03:19 PM - What can GPS and XM antennas see through? (cskelt@earthlink.net) 7. 03:38 PM - Re: What can GPS and XM antennas see through? (BobsV35B@aol.com) 8. 04:10 PM - Re: What can GPS and XM antennas see through? (ROGER & JEAN CURTIS) 9. 04:38 PM - Re: System Off Current Requirements... (user9253) 10. 04:41 PM - Re: Re: System Off Current Requirements... (Matt Dralle) 11. 05:10 PM - Re: What can GPS and XM antennas see through? (BobsV35B@aol.com) 12. 06:34 PM - Re: What can GPS and XM antennas see through? (ROGER & JEAN CURTIS) 13. 08:26 PM - Re: What can GPS and XM antennas see through? (richard sipp) ________________________________ Message 1 _____________________________________ Time: 05:22:52 AM PST US From: Vincent Himsl Subject: RE: Fried EXP2BUS was AeroElectric-List: EXP2BUS and non-functioning alternator Hello=2C Simple Things revisited. Do you have a thick cable going from the engine case to the negative return on your battery? I used a thick braided mesh cable to the firewall and fro m there a thick Van's 3/8" diameter (I think) to the battery. The reason I ask is that an ohmmeter check will show continuity possibly th rough some round about way=2C but the engine is electrically isolated from the engine frame by the rubber 'Lord' mounts and you need as thick a cable (electronically speaking) returning to the battery (neg) as leaving it (Pos ) Also check the ground return for your 'EXP BUS'. From the block diagram at 'ControlVison' it is needed for the relays and internal over voltage module to work properly. Ideally measure the voltage from the battery neg termina l to the EXP BUS ground. It should be zero VDC=2C anything else indicates a poor ground. Speaking of the EXP BUS internal over voltage protection=2C a poor ground could affect its operation causing it to erratically shut dow n the alternator. This would appear to you as a defective alternator. Next the alternator: Try the following with the engine NOT running. Measure your battery voltage exactly. Next disconnect the 'T' connector at your alternator. Turn on your master and alternator as if it was connected (Engine NOT running) and 'again' measure the voltage on the 'IG' pin of the connector. Now measure the 'L' pin voltage. The pin that reads the same voltage as the battery should be your 'IG" lead . The one that reads the battery voltage minus ~.7VDC should be your (LED) 'L' lead. These were my readings using a Fluke digital multimeter. Failing this=2C remove the alternator and take it to an auto-electrical shop and ask them to bench test it. If it passes=2C you will know your problem lies elsewhere. EXP BUS If the alternator checks out good=2C then the next item on the list of susp ects is the EXP BUS Internal Over Voltage Controler. As a test=2C hook up a temporary Alternator switch ('IG' lead) to bypass the EXP BUS. Fire up the engine to see if all is well carefully monitoring your voltage to make sur e you do not in fact have an over voltage condition. If you alternator work s you now can narrow in on the EXP BUS wiring=2C and then finally=2C the un it itself. The idea is to divide and conquer. Still I suspect in the end you will find that it boils down to a simple wiring error. At least that has been my exp erience Good Luck=2C Vince H. Washington State - USA N8432 RV8 - Ready for Final Inspection > Thanks Ed. I'll check for any signs of high current. I was able to > check the power at the alternator and the 12V is getting to the right > pin=2C the warning lamp lead is connected to the right place (and showing > about 1V=2C not sure if that's what you would expect to see the other sid e > of a 12V LED) but it "felt right". _________________________________________________________________ Insert movie times and more without leaving Hotmail=AE. http://windowslive.com/Tutorial/Hotmail/QuickAdd?ocid=TXT_TAGLM_WL_HM_Tut orial_QuickAdd1_052009 ________________________________ Message 2 _____________________________________ Time: 11:40:31 AM PST US From: Matt Dralle Subject: AeroElectric-List: System Off Current Requirements... Greetings, Since all of the panel and internal wiring is done, I thought I do a "System Off" current draw check today. There is a "keep alive" buss coming off the VP-200 system that I have connected the GRT HX displays to as well as the Kenwood DNX8120 and a couple of other things. I've currently got the standard Concord 25RG-XC battery that Van's sells. With the VP-200 system "off", I'm measuring about 6ma of constant current draw. My question is, how long is the standard battery going to last with this amount of draw? Also, is the Concord 25RG-XC the best choice for batteries? I've got an IO-390 and the battery is mounted in the back of the my RV-8. Is this battery going to have the staying power to support the electronics I've got as well as crank the engine? Thanks in advance for the advice. Matt Dralle RV-8 #82880 Wiring Done, Gear Next... ________________________________ Message 3 _____________________________________ Time: 12:18:58 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: System Off Current Requirements... At 01:34 PM 5/3/2009, you wrote: >Greetings, > >Since all of the panel and internal wiring is done, I thought I do a >"System Off" current draw check today. There is a "keep alive" buss >coming off the VP-200 system that I have connected the GRT HX >displays to as well as the Kenwood DNX8120 and a couple of other >things. I've currently got the standard Concord 25RG-XC battery >that Van's sells. With the VP-200 system "off", I'm measuring about >6ma of constant current draw. > > >My question is, how long is the standard battery going to last with >this amount of draw? Since this battery is rated for service in aircraft (i.e. not a 20 hr rated but a 1 hr rate) then your battery charge available to support keep alive loads is much better than 24000/6 or 4,000 hours. In other words, if the airplane is flown with some degree of regularity, those loads are insignificant. If you were going to park the airplane for several months, then it would be a good idea to either disconnect the battery in a fully charged state . . . or leave a battery tender type charger attached for the duration of storage. >Also, is the Concord 25RG-XC the best choice for batteries? I've >got an IO-390 and the battery is mounted in the back of the my >RV-8. Is this battery going to have the staying power to support >the electronics I've got as well as crank the engine? You don't mention what your e-bus loads are and whether or not you have more than one engine driven power source. You need to match your e-bus endurance requirements against your design goals for battery only operations. There are RV-8's with rear mounted 18 a.h. battery and Figure Z-13/8 that perform to the owner's design goals . . . but without knowing more detail about your goals and your system configuration, real reasoned advice is not possible. Bob . . . ----------------------------------------) ( . . . a long habit of not thinking ) ( a thing wrong, gives it a superficial ) ( appearance of being right . . . ) ( ) ( -Thomas Paine 1776- ) ---------------------------------------- ________________________________ Message 4 _____________________________________ Time: 01:08:52 PM PST US From: Ernest Christley Subject: Re: AeroElectric-List: System Off Current Requirements... Robert L. Nuckolls, III wrote: > > If you were going to park the airplane for several > months, then it would be a good idea to either disconnect > the battery in a fully charged state . . . or leave > a battery tender type charger attached for the duration > of storage. > Just an idea. The battery on a Dyke Delta is accessed through an external panel near the rear of the aircraft. I built my access panel out of one of those solar trickle chargers. Two birds. One stone. Wait. Should I be talking about knocking down birds with rocks on this list? -- http://www.ernest.isa-geek.org ________________________________ Message 5 _____________________________________ Time: 01:42:52 PM PST US From: Charlie England Subject: Re: AeroElectric-List: System Off Current Requirements... Matt Dralle wrote: > Greetings, > > Since all of the panel and internal wiring is done, I thought I do a "System Off" current draw check today. There is a "keep alive" buss coming off the VP-200 system that I have connected the GRT HX displays to as well as the Kenwood DNX8120 and a couple of other things. I've currently got the standard Concord 25RG-XC battery that Van's sells. With the VP-200 system "off", I'm measuring about 6ma of constant current draw. > > My question is, how long is the standard battery going to last with this amount of draw? > > Also, is the Concord 25RG-XC the best choice for batteries? I've got an IO-390 and the battery is mounted in the back of the my RV-8. Is this battery going to have the staying power to support the electronics I've got as well as crank the engine? > > Thanks in advance for the advice. > > Matt Dralle > RV-8 #82880 > Wiring Done, Gear Next... Absolutely stunning panel. Of course, I could support all my flying habits just on the interest on the money it must have cost. :-) You shouldn't have any problem with engine start, and once it's running, the alternator is what powers all your electrical goodies. As long as the alternator is sized to power everything electrical & still have some snort to charge the battery, you're good to go. If the keep-alive buss is drawing 6mA (6 one-thousandths of one amp), and the battery is a 25 ampere/hour battery (25 thousand mA/hr), then it should theoretically last a bit less than 25,000/6=4,166 hours. With a generous fudge factor, call it better than 3000 hrs if the battery is in perfect condition and fully charged. Somebody check my math. Have you done the 'dead alternator' analysis to see how long the battery will keep your essential electrical stuff alive if the alternator fails in flight? For that, you need the manufacturer's info sheet on how long it will last at *your* essential equipment's current draw. (It's not a linear function.) Charlie Charlie ________________________________ Message 6 _____________________________________ Time: 03:19:57 PM PST US From: "cskelt@earthlink.net" Subject: AeroElectric-List: What can GPS and XM antennas see through? Folks, I'm installing a Garmin 496 in my Lancair 320. The Garmin manual suggests placing the GPS and XM antennas supplied with the unit where they can see the sky through the canopy. This could be achieved by placing the two devices on the glare shield. However it would be an easier installation if I were to place the two antennas below the glare shield. This way, there'd be no awkward electrical connections to deal with when removing or replacing the glare shield. If the antennas can see through perspex, (or laminated auto glass) can they additionally see through the skinny fiberglass molding covered with headlining material? Thanks in advance for any advice. Chris Skelt. __________________ cskelt@earthlink.net ________________________________ Message 7 _____________________________________ Time: 03:38:12 PM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: What can GPS and XM antennas see through? Good Evening Chris, The antennas will look through that glareshield just fine. However, you must remember that any distance below the very top of the airplane will reduce the amount of sky that can be seen via the antennas. We have found that antennas mounted on top of the glove box and under the glareshield work reasonably well in various Bonanzas. Happy Skies Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 In a message dated 5/3/2009 5:21:28 P.M. Central Daylight Time, cskelt@earthlink.net writes: Folks, I'm installing a Garmin 496 in my Lancair 320. The Garmin manual suggests placing the GPS and XM antennas supplied with the unit where they can see the sky through the canopy. This could be achieved by placing the two devices on the glare shield. However it would be an easier installation if I were to place the two antennas below the glare shield. This way, there'd be no awkward electrical connections to deal with when removing or replacing the glare shield. If the antennas can see through perspex, (or laminated auto glass) can they additionally see through the skinny fiberglass molding covered with headlining material? Thanks in advance for any advice. Chris Skelt. __________________ _cskelt@earthlink.net_ (mailto:cskelt@earthlink.net) (http://www.matronics.com/Navigator?AeroElectric-List) (http://www.matronics.com/contribution) **************The Average US Credit Score is 692. See Yours in Just 2 Easy Steps! ay5309AvgfooterNO62) ________________________________ Message 8 _____________________________________ Time: 04:10:58 PM PST US From: "ROGER & JEAN CURTIS" Subject: RE: AeroElectric-List: What can GPS and XM antennas see through? Are there any published specs as to what materials, at what thickness, satellite antennas can see through without a large attenuation of signal strength? If so can you point me toward them? Thanks, Roger Good Evening Chris, The antennas will look through that glareshield just fine. However, you must remember that any distance below the very top of the airplane will reduce the amount of sky that can be seen via the antennas. We have found that antennas mounted on top of the glove box and under the glareshield work reasonably well in various Bonanzas. Happy Skies Old Bob In a message dated 5/3/2009 5:21:28 P.M. Central Daylight Time, cskelt@earthlink.net writes: Folks, I'm installing a Garmin 496 in my Lancair 320. The Garmin manual suggests placing the GPS and XM antennas supplied with the unit where they can see the sky through the canopy. This could be achieved by placing the two devices on the glare shield. However it would be an easier installation if I were to place the two antennas below the glare shield. This way, there'd be no awkward electrical connections to deal with when removing or replacing the glare shield. If the antennas can see through perspex, (or laminated auto glass) can they additionally see through the skinny fiberglass molding covered with headlining material? Thanks in advance for any advice. Chris Skelt. __________________ ________________________________ Message 9 _____________________________________ Time: 04:38:10 PM PST US Subject: AeroElectric-List: Re: System Off Current Requirements... From: "user9253" I see some space left on the panel that is not being used. What a waste! I can imagine his radio transmissions: Center: descend and maintain 7 thousand. Turn right heading 320 degrees. Contact approach control on 126.65. Matt: Center, can you wait until the commercial? I do not want to miss this good part on TV. [Laughing] Joe -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=242558#242558 ________________________________ Message 10 ____________________________________ Time: 04:41:53 PM PST US From: Matt Dralle Subject: Re: AeroElectric-List: Re: System Off Current Requirements... At 04:36 PM 5/3/2009 Sunday, you wrote: > >I see some space left on the panel that is not being used. What a waste! > >I can imagine his radio transmissions: > >Center: descend and maintain 7 thousand. Turn right heading 320 degrees. Contact approach control on 126.65. > >Matt: Center, can you wait until the commercial? I do not want to miss this >good part on TV. [Laughing] > >Joe Now, that's funny, right there...! :-) Matt PS - And, btw, I'm saving that little space on the right hand side of the panel for an analog HOBBS meter. NOT. ;-) ________________________________ Message 11 ____________________________________ Time: 05:10:28 PM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: What can GPS and XM antennas see through? Good Evening Roger, If such a document exists, I am not aware of it! Do Not Archive Happy Skies Old Bob AKA Bob Siegfried Ancient Aviator 628 West 86th Street Downers Grove, IL 60516 630 985-8502 Stearman N3977A Brookeridge Air Park LL22 In a message dated 5/3/2009 6:12:52 P.M. Central Daylight Time, mrspudandcompany@verizon.net writes: Are there any published specs as to what materials, at what thickness, satellite antennas can see through without a large attenuation of signal strength? If so can you point me toward them? Thanks, Roger **************The Average US Credit Score is 692. See Yours in Just 2 Easy Steps! ay5309AvgfooterNO62) ________________________________ Message 12 ____________________________________ Time: 06:34:51 PM PST US From: "ROGER & JEAN CURTIS" Subject: RE: AeroElectric-List: What can GPS and XM antennas see through? Good Evening Roger, If such a document exists, I am not aware of it! Do Not Archive Happy Skies Old Bob Hi Bob, Apparently the GPS antenna can see through some plastics and light foam but not through wood, metal, dense foam, or carbon fiber, to name a few. It seems your best bet is to have nothing but air between the antenna and satellite, for best reception. Roger ________________________________ Message 13 ____________________________________ Time: 08:26:48 PM PST US From: "richard sipp" Subject: Re: AeroElectric-List: What can GPS and XM antennas see through? I have these antennas mounted ahead of the firewall under the ~1/8 thick painted fiberglass cowling. No problems at one year in service. I believe this is a relatively common practice in the RV community. Dick Sipp RV10 N110DV ------------------------------------------------------------------------------------- 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.