---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 05/17/08: 7 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 09:06 AM - Schematic Review (Scott Freeman) 2. 10:35 AM - Re: Schematic Review (Terry McMillan) 3. 04:05 PM - Getting Off Topic, Was: Schematic Review (BobsV35B@aol.com) 4. 04:30 PM - Re: Getting Off Topic, Was: Schematic Review (bob noffs) 5. 04:40 PM - Re: Getting Off Topic, Was: Schematic Review (BobsV35B@aol.com) 6. 07:37 PM - Re: Getting Off Topic, Was: Schematic Review (Scott Freeman) 7. 08:38 PM - Re: Getting Off Topic, Was: Schematic Review (S. Ramirez) ________________________________ Message 1 _____________________________________ Time: 09:06:01 AM PST US From: "Scott Freeman" Subject: AeroElectric-List: Schematic Review I am building an RV-7A. The panel will be all electric and set-up for light IFR. I have completed my schematic and would like some input since I am new at this electrical stuff. The basic configuration is a single alternator/two battery system. The primary and aux battery are the same size (17 amp-hr) and can both be used for starting. There is a main and essential (avionics) buss that can be isolated on either battery. I envision the modes to be: 1) Normal operation: Start with primary batt, run system off alternator and primary batt, only turn aux batt on long enough to "top off" its charge and then isolate it back off. 2) Alternator failure and/or main batt failure: Power the avionics buss with the isolated aux battery for emergency power until able to land. This will be up to 2 hours for the avionics. Note: If there is remaining power in the Primary Batt- I would be able to get some time with it also. 3) Ground Start- If the Primary Batt is drained during a hard start situation, the option to switch to the aux battery for start is there. Since these are smaller dry cells, I like this option. 4) Plan is to rotate the aux battery to the Main Battery every other year or as necessary and replace the aux battery with a fresh one. This will provide preventative maintenance for the batteries. Thanks for any input you can provide to make sure the schematic doesn't have errors. Scott Freeman ________________________________ Message 2 _____________________________________ Time: 10:35:45 AM PST US From: "Terry McMillan" Subject: RE: AeroElectric-List: Schematic Review Scott, a couple of things I noticed; you have 2 unprotected unswitched circuits directly connected to the Aux battery, namely the Aux Battery Bus and the Aux Battery Switch. These both pass thru the firewall to the cockpit, and if a fault to ground occured they could not be turned off. My suggestion would be an in-line fuse for the Aux Bat Bus, and move the feed to terminal 2 of the Aux Bat Master Switch to the other side of the Aux Bat Relay. As shown turning on the Aux Bat Switch will energize both the Main and Avionics buses, so presumably you would manually turn off the loads on the main bus. To me it would make more sense to wire the fuse-protected lead from the Aux Battery direct to the Aux Bat Avionics Master, this way it would be an emergency-only switch, and the Aux Batt Master switch would just be used to parallel the batteries for starting or to charge the Aux battery. Personally I see it as a bad idea to mix emergency control functions with routine functions on the same switch. FWIW, a good suggestion I've seen is to put the DC power receptacle on the alway-hot bus. One advantage of this is that you can recharge the battery on the ground without opening the cowling. Terry McMillan RV7 FADEC dual electrical >From: "Scott Freeman" >To: >Subject: AeroElectric-List: Schematic Review >Date: Sat, 17 May 2008 12:00:56 -0400 > >I am building an RV-7A. The panel will be all electric and set-up for >light IFR. I have completed my schematic and would like some input since I >am new at this electrical stuff. > >The basic configuration is a single alternator/two battery system. The >primary and aux battery are the same size (17 amp-hr) and can both be used >for starting. There is a main and essential (avionics) buss that can be >isolated on either battery. > >I envision the modes to be: >1) Normal operation: Start with primary batt, run system off alternator and >primary batt, only turn aux batt on long enough to "top off" its charge and >then isolate it back off. > >2) Alternator failure and/or main batt failure: Power the avionics buss >with the isolated aux battery for emergency power until able to land. This >will be up to 2 hours for the avionics. Note: If there is remaining power >in the Primary Batt- I would be able to get some time with it also. > >3) Ground Start- If the Primary Batt is drained during a hard start >situation, the option to switch to the aux battery for start is there. >Since these are smaller dry cells, I like this option. > >4) Plan is to rotate the aux battery to the Main Battery every other year >or as necessary and replace the aux battery with a fresh one. This will >provide preventative maintenance for the batteries. > >Thanks for any input you can provide to make sure the schematic doesn't >have errors. > >Scott Freeman ><< N246SFElectricalSystemDesignRev2-forReview.xls >> ________________________________ Message 3 _____________________________________ Time: 04:05:10 PM PST US From: BobsV35B@aol.com Subject: Getting Off Topic, Was: AeroElectric-List: Schematic Review Good Afternoon Scott, I keep seeing reference to Light IFR and an occasional reference to heavy IFR. Would you mind telling me what you consider to be light IFR? If you were on top of coastal fog with a two hundred foot ceiling below, would a full ILS to a fully approach lit runway be light or heavy IFR? Or, if you are enroute, constantly in cloud, but with ceilings along your route and at destination well above one thousand and three, would that be light IFR? I have a hard time discerning just what is meant by light IFR. 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 Do Not Archive In a message dated 5/17/2008 11:08:54 A.M. Central Daylight Time, sgfreeman@smyth.net writes: I am building an RV-7A. The panel will be all electric and set-up for light IFR. **************Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001) ________________________________ Message 4 _____________________________________ Time: 04:30:59 PM PST US From: "bob noffs" Subject: Re: Getting Off Topic, Was: AeroElectric-List: Schematic Review hi bob, light ifr is if i am right seat with a very competent and proficient ifr pilot. hard ifr is if i am solo! bob noffs ----- Original Message ----- From: BobsV35B@aol.com To: aeroelectric-list@matronics.com Sent: Saturday, May 17, 2008 6:00 PM Subject: Getting Off Topic, Was: AeroElectric-List: Schematic Review Good Afternoon Scott, I keep seeing reference to Light IFR and an occasional reference to heavy IFR. Would you mind telling me what you consider to be light IFR? If you were on top of coastal fog with a two hundred foot ceiling below, would a full ILS to a fully approach lit runway be light or heavy IFR? Or, if you are enroute, constantly in cloud, but with ceilings along your route and at destination well above one thousand and three, would that be light IFR? I have a hard time discerning just what is meant by light IFR. 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 Do Not Archive In a message dated 5/17/2008 11:08:54 A.M. Central Daylight Time, sgfreeman@smyth.net writes: I am building an RV-7A. The panel will be all electric and set-up for light IFR. ------------------------------------------------------------------------- ----- Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. ________________________________ Message 5 _____________________________________ Time: 04:40:04 PM PST US From: BobsV35B@aol.com Subject: Re: Getting Off Topic, Was: AeroElectric-List: Schematic Review I Like It! l Like It!! 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 5/17/2008 6:32:48 P.M. Central Daylight Time, icubob@newnorth.net writes: hi bob, light ifr is if i am right seat with a very competent and proficient ifr pilot. hard ifr is if i am solo! bob noffs **************Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. (http://food.aol.com/dinner-tonight?NCID=aolfod00030000000001) ________________________________ Message 6 _____________________________________ Time: 07:37:35 PM PST US From: "Scott Freeman" Subject: Re: Getting Off Topic, Was: AeroElectric-List: Schematic Review Bob, Sorry for the "light IFR" nomenclature. I knew after I sent it that it would probably raise some eyebrows. To me it means it means I have some personal limits that I want to stay within for single pilot IFR. Rule 1: Never fly on purpose into sustained IMC conditions Rule 2: Use IFR as a means to get on top only if the layer is less than 2000 ft thick. If it is more than 2000' thick, stay home. Rule 3: When ever possible, use IFR flight plans to work on flying skills and to have constant contact with ATC Rule 4: Use IFR to get down through a layer for an approach to an airport with ceilings at least 300 ft. above minimums. If ceilings are less than 300 above, try to find another airport that meets that criteria even if you miss getting home when you wanted. Rule 5: Never, Never, Never fly when the slightest possibility of icing conditions or sustained IMC conditions are forecast for any part of your route Rule 6: Practice VFR navigation, including pilotage and dead reckoning on a regular basis to keep well rounded Rule 7: Plan on sleeping on some airport couches once in a while Rule 8: Since we are human and things don't always go as we expect, practice, practice, and practice so if unfortunate and unforseen circumstances lead to one of the rules being violated, you can survive and come home to your family in one piece To me it boils down to the old saying: It is better to be on the ground wishing you were in the air than in the air wishing your were on the ground. Scott ----- Original Message ----- From: BobsV35B@aol.com To: aeroelectric-list@matronics.com Sent: Saturday, May 17, 2008 7:00 PM Subject: Getting Off Topic, Was: AeroElectric-List: Schematic Review Good Afternoon Scott, I keep seeing reference to Light IFR and an occasional reference to heavy IFR. Would you mind telling me what you consider to be light IFR? If you were on top of coastal fog with a two hundred foot ceiling below, would a full ILS to a fully approach lit runway be light or heavy IFR? Or, if you are enroute, constantly in cloud, but with ceilings along your route and at destination well above one thousand and three, would that be light IFR? I have a hard time discerning just what is meant by light IFR. 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 Do Not Archive In a message dated 5/17/2008 11:08:54 A.M. Central Daylight Time, sgfreeman@smyth.net writes: I am building an RV-7A. The panel will be all electric and set-up for light IFR. ------------------------------------------------------------------------- ----- Wondering what's for Dinner Tonight? Get new twists on family favorites at AOL Food. ________________________________ Message 7 _____________________________________ Time: 08:38:03 PM PST US From: "S. Ramirez" Subject: RE: Getting Off Topic, Was: AeroElectric-List: Schematic Review Scott, your version of "light IFR" sounds like non-commercial flying to me. I think it's wise for us guys that don't fly in IMC too much to want to fly only in light IMC. Those are good rules, and the goods don't have to be there by a certain time. Simon Copyright C 2008 From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Scott Freeman Sent: Saturday, May 17, 2008 10:33 PM Subject: Re: Getting Off Topic, Was: AeroElectric-List: Schematic Review Bob, Sorry for the "light IFR" nomenclature. I knew after I sent it that it would probably raise some eyebrows. To me it means it means I have some personal limits that I want to stay within for single pilot IFR. Rule 1: Never fly on purpose into sustained IMC conditions Rule 2: Use IFR as a means to get on top only if the layer is less than 2000 ft thick. If it is more than 2000' thick, stay home. Rule 3: When ever possible, use IFR flight plans to work on flying skills and to have constant contact with ATC Rule 4: Use IFR to get down through a layer for an approach to an airport with ceilings at least 300 ft. above minimums. If ceilings are less than 300 above, try to find another airport that meets that criteria even if you miss getting home when you wanted. Rule 5: Never, Never, Never fly when the slightest possibility of icing conditions or sustained IMC conditions are forecast for any part of your route Rule 6: Practice VFR navigation, including pilotage and dead reckoning on a regular basis to keep well rounded Rule 7: Plan on sleeping on some airport couches once in a while Rule 8: Since we are human and things don't always go as we expect, practice, practice, and practice so if unfortunate and unforseen circumstances lead to one of the rules being violated, you can survive and come home to your family in one piece To me it boils down to the old saying: It is better to be on the ground wishing you were in the air than in the air wishing your were on the ground. Scott ------------------------------------------------------------------------------------- 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.