---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Tue 06/24/03: 22 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 07:11 AM - Re: LightSpeed wiring (Phil Birkelbach) 2. 07:14 AM - Audio Isolation Amplifier (Robert L. Nuckolls, III) 3. 08:21 AM - Re: LightSpeed wiring (Joel Harding) 4. 08:30 AM - recording intercom with a digital voice recorder (Chris W) 5. 09:07 AM - Re: LightSpeed wiring (Terry Watson) 6. 09:28 AM - Re: LightSpeed wiring (Dan Checkoway) 7. 09:35 AM - Re: LightSpeed wiring (Werner Schneider) 8. 09:45 AM - Re: LightSpeed wiring (Matt Prather) 9. 09:57 AM - Re: LightSpeed wiring (David) 10. 10:01 AM - Re: LightSpeed wiring (Phil Birkelbach) 11. 10:31 AM - Re: LightSpeed wiring (I-Blackler, Wayne R) 12. 12:22 PM - Re: LightSpeed wiring (Joel Harding) 13. 02:41 PM - LEDs (Fergus Kyle) 14. 02:54 PM - Is the E-Bus that Essential? (Robert Whitaker) 15. 03:47 PM - Re: Is the E-Bus that Essential? (Matt Prather) 16. 04:07 PM - Re: Is the E-Bus that Essential? (Robert L. Nuckolls, III) 17. 04:29 PM - Re: Is the E-Bus that Essential? (Kevin Horton) 18. 04:47 PM - Re: LightSpeed wiring (Phil Birkelbach) 19. 05:18 PM - Re: Is the E-Bus that Essential? (Phil Birkelbach) 20. 07:02 PM - Re: LightSpeed wiring (Robert L. Nuckolls, III) 21. 07:03 PM - Re: LightSpeed wiring (Robert L. Nuckolls, III) 22. 07:38 PM - Re: isolated ground wire for avionics in metal airplane (CardinalNSB@aol.com) ________________________________ Message 1 _____________________________________ Time: 07:11:10 AM PST US From: "Phil Birkelbach" Subject: Re: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: "Phil Birkelbach" Dan, That's exactly how I plan to wire mine up. The problem that I see from their wiring description is that long unprotected wire from the battery to the breaker. I'd rather get mine fused right away on the battery buss and then I can run the wire all over the place without having to worry about it. Their thought process may be circuit reliablitly by eliminating connections, but the system that you describe should prove to be very robust besides you have another ignition source. If I were putting in two EI's then I might try to figure out an alternate way to power the other one. Like one from the E-buss and one from the battery buss. Godspeed, Phil Birkelbach - Houston Texas RV-7 N727WB (Reserved) - Canopy http://www.myrv7.com ----- Original Message ----- From: "Dan Checkoway" Subject: AeroElectric-List: LightSpeed wiring > --> AeroElectric-List message posted by: "Dan Checkoway" > > Bob & folks, > > I'm installing a single LightSpeed Plasma II ignition in my RV-7 (single EI, > single mag), and I'm considering straying slightly from the wiring > installation notes provided with the LSE system. > > They recommend wiring directly to and from the battery and using a pullable > breaker. Basically, positive battery terminal direct to a pullable 5A > breaker, then an optional on/off toggle switch, then the brain, then wire > directly to the negative battery terminal. They recommend bypassing busses > in this manner. > > Here's what I would *like* to do instead: > > - power wired from a 5A fuse on the always-hot battery bus, which is roughly > 6" away (plus an inch or three) from the battery (+) terminal > - no pullable circuit breaker, let the 5A fuse do its job > - standard 1-3 ON/OFF toggle switch > - ground wired directly to the 48/24 firewall ground block, which is > connected to the battery via 5" of 2 AWG > > Do you see any potential gotchas in straying from LSE's recommendations in > this way? I don't really see the purpose of using a pullable breaker when > you use the optional on/off toggle switch and figure a fuse will do fine. I > have control in normal cases, and the wires are protected. I guess I could > always use a 5A breaker switch, but again I don't really see the point when > a fuse will do the same job cheaper, lighter, etc. > > As far as the ground goes, is there any possibility of noise affecting the > LightSpeed when ground is shared with every device in the plane, even when > it's grounded so deliberately close to the battery (but not *quite* to the > negative terminal)? > > Thanks, > )_( Dan > RV-7 N714D > http://www.rvproject.com > > ________________________________ Message 2 _____________________________________ Time: 07:14:47 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Audio Isolation Amplifier --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" Got to the workbench and fine-tuned some features of the design last night. I'll publish the data package this evening after a last check of the data. Bob . . . -------------------------------------------- ( Knowing about a thing is different than ) ( understanding it. One can know a lot ) ( and still understand nothing. ) ( C.F. Kettering ) -------------------------------------------- ________________________________ Message 3 _____________________________________ Time: 08:21:35 AM PST US Subject: Re: AeroElectric-List: LightSpeed wiring From: Joel Harding --> AeroElectric-List message posted by: Joel Harding Phil, I'm trying to decide on the best way to implement Klaus's schematic also. The question I have is, how important is the location of the protection in a wire run. Lightspeed doesn't show the breaker location in their drawing, but I assumed that since the breaker is the weak point, it wouldn't make too much difference where it is located in the line. Can someone clear this up for me? Joel Harding On Tuesday, Jun 24, 2003, at 08:07 America/Denver, Phil Birkelbach wrote: > --> AeroElectric-List message posted by: "Phil Birkelbach" > > > Dan, > > That's exactly how I plan to wire mine up. The problem that I see from > their wiring description is that long unprotected wire from the > battery to > the breaker. I'd rather get mine fused right away on the battery buss > and > then I can run the wire all over the place without having to worry > about it. > Their thought process may be circuit reliablitly by eliminating > connections, > but the system that you describe should prove to be very robust > besides you > have another ignition source. If I were putting in two EI's then I > might > try to figure out an alternate way to power the other one. Like one > from > the E-buss and one from the battery buss. > > Godspeed, > > Phil Birkelbach - Houston Texas > RV-7 N727WB (Reserved) - Canopy > http://www.myrv7.com > > ----- Original Message ----- > From: "Dan Checkoway" > To: > Subject: AeroElectric-List: LightSpeed wiring > > >> --> AeroElectric-List message posted by: "Dan Checkoway" > >> >> Bob & folks, >> >> I'm installing a single LightSpeed Plasma II ignition in my RV-7 >> (single > EI, >> single mag), and I'm considering straying slightly from the wiring >> installation notes provided with the LSE system. >> >> They recommend wiring directly to and from the battery and using a > pullable >> breaker. Basically, positive battery terminal direct to a pullable 5A >> breaker, then an optional on/off toggle switch, then the brain, then >> wire >> directly to the negative battery terminal. They recommend bypassing > busses >> in this manner. >> >> Here's what I would *like* to do instead: >> >> - power wired from a 5A fuse on the always-hot battery bus, which is > roughly >> 6" away (plus an inch or three) from the battery (+) terminal >> - no pullable circuit breaker, let the 5A fuse do its job >> - standard 1-3 ON/OFF toggle switch >> - ground wired directly to the 48/24 firewall ground block, which is >> connected to the battery via 5" of 2 AWG >> >> Do you see any potential gotchas in straying from LSE's >> recommendations in >> this way? I don't really see the purpose of using a pullable breaker >> when >> you use the optional on/off toggle switch and figure a fuse will do >> fine. > I >> have control in normal cases, and the wires are protected. I guess I > could >> always use a 5A breaker switch, but again I don't really see the point > when >> a fuse will do the same job cheaper, lighter, etc. >> >> As far as the ground goes, is there any possibility of noise >> affecting the >> LightSpeed when ground is shared with every device in the plane, even >> when >> it's grounded so deliberately close to the battery (but not *quite* >> to the >> negative terminal)? >> >> Thanks, >> )_( Dan >> RV-7 N714D >> http://www.rvproject.com >> >> > > > _- > ====================================================================== > _- > ====================================================================== > _- > ====================================================================== > _- > ====================================================================== > > ________________________________ Message 4 _____________________________________ Time: 08:30:30 AM PST US From: Chris W Subject: AeroElectric-List: recording intercom with a digital voice recorder --> AeroElectric-List message posted by: Chris W I would like to tie in a digital voice recorder to the intercom for 2 purposes. First to record everything while I am doing my flight training. Second to be able to play back what ATC just said. I found an adapter wire in the Aircraft Spruce catalog that you stick between the intercom and your headset plug that has electronics that convert the headphone signal down to a mic signal. That's great for recording. Then they have a CD Player adapter where you also insert the plug in between the intercom and your headset plug and then plug the little 1/8" plug into the headphone jack of a CD player or in this case the voice recorder. But then there are the cell phone adapters. Can those be connected to a voice recorder some how and record all intercom traffic? And then play it back through the intercom? Then there is the issue of mixing stereo and mono plugs. I don't really care if I loose the option to hear stereo music as long as the signal is still coming through both ears. Can some one please clear this up and let me know what the best solution is? I'm also looking for suggestions on MP3 players/voice recorders. I have also seen some MP3 player/recorders that can record from a line in signal, would that be a better solution? Has anyone seen or used these? The only one I know of right now is called a Ripflash. They have several different models. Their web site is here http://www.pogoproducts.com/ -- Chris Woodhouse 3147 SW 127th St. Oklahoma City, OK 73170 405-691-5206 chrisw@programmer.net N35 20.492' W97 34.342' "They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety." -- Benjamin Franklin, 1759 Historical Review of Pennsylvania ________________________________ Message 5 _____________________________________ Time: 09:07:33 AM PST US From: "Terry Watson" Subject: RE: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: "Terry Watson" Light Speed's instructions say they want us to "route the positive power lead to a 5A pull-able breaker and then to the battery plus terminal, bypassing any electrical bus or master solenoid." And "If a toggle switch is used as an on/off switch, it should be installed next to the breaker." And also: "Route the negative lead directly to the battery ground terminal (not airframe ground buss) to avoid ignition noise...." I don't like the idea of running an unfused always hot line direct from the battery in the front baggage compartment floor on the right side of my RV-8A to the ignition toggles on the left side of the panel. I also don't like the idea of this one of a couple dozen circuits in the airplane going directly to both terminals of the battery; no battery buss, no ground buss; directly to the terminal. My inclination is to run it to a 5A fuse on a battery bus and ground it to a ground bus. Terry -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Joel Harding Subject: Re: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: Joel Harding Phil, I'm trying to decide on the best way to implement Klaus's schematic also. The question I have is, how important is the location of the protection in a wire run. Lightspeed doesn't show the breaker location in their drawing, but I assumed that since the breaker is the weak point, it wouldn't make too much difference where it is located in the line. Can someone clear this up for me? Joel Harding On Tuesday, Jun 24, 2003, at 08:07 America/Denver, Phil Birkelbach wrote: > --> AeroElectric-List message posted by: "Phil Birkelbach" > > > Dan, > > That's exactly how I plan to wire mine up. The problem that I see from > their wiring description is that long unprotected wire from the > battery to > the breaker. I'd rather get mine fused right away on the battery buss > and > then I can run the wire all over the place without having to worry > about it. > Their thought process may be circuit reliablitly by eliminating > connections, > but the system that you describe should prove to be very robust > besides you > have another ignition source. If I were putting in two EI's then I > might > try to figure out an alternate way to power the other one. Like one > from > the E-buss and one from the battery buss. > > Godspeed, > > Phil Birkelbach - Houston Texas > RV-7 N727WB (Reserved) - Canopy > http://www.myrv7.com > > ----- Original Message ----- > From: "Dan Checkoway" > To: > Subject: AeroElectric-List: LightSpeed wiring > > >> --> AeroElectric-List message posted by: "Dan Checkoway" > >> >> Bob & folks, >> >> I'm installing a single LightSpeed Plasma II ignition in my RV-7 >> (single > EI, >> single mag), and I'm considering straying slightly from the wiring >> installation notes provided with the LSE system. >> >> They recommend wiring directly to and from the battery and using a > pullable >> breaker. Basically, positive battery terminal direct to a pullable 5A >> breaker, then an optional on/off toggle switch, then the brain, then >> wire >> directly to the negative battery terminal. They recommend bypassing > busses >> in this manner. >> >> Here's what I would *like* to do instead: >> >> - power wired from a 5A fuse on the always-hot battery bus, which is > roughly >> 6" away (plus an inch or three) from the battery (+) terminal >> - no pullable circuit breaker, let the 5A fuse do its job >> - standard 1-3 ON/OFF toggle switch >> - ground wired directly to the 48/24 firewall ground block, which is >> connected to the battery via 5" of 2 AWG >> >> Do you see any potential gotchas in straying from LSE's >> recommendations in >> this way? I don't really see the purpose of using a pullable breaker >> when >> you use the optional on/off toggle switch and figure a fuse will do >> fine. > I >> have control in normal cases, and the wires are protected. I guess I > could >> always use a 5A breaker switch, but again I don't really see the point > when >> a fuse will do the same job cheaper, lighter, etc. >> >> As far as the ground goes, is there any possibility of noise >> affecting the >> LightSpeed when ground is shared with every device in the plane, even >> when >> it's grounded so deliberately close to the battery (but not *quite* >> to the >> negative terminal)? >> >> Thanks, >> )_( Dan >> RV-7 N714D >> http://www.rvproject.com >> >> > > > _- > ====================================================================== > _- > ====================================================================== > _- > ====================================================================== > _- > ====================================================================== > > ________________________________ Message 6 _____________________________________ Time: 09:28:30 AM PST US From: "Dan Checkoway" Subject: Re: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: "Dan Checkoway" I vaguely remember seeing their recommended circuit go: (+) terminal 5A breaker optional switch brain box ground to (-) terminal )_( Dan RV-7 N714D http://www.rvproject.com ----- Original Message ----- From: "Joel Harding" Subject: Re: AeroElectric-List: LightSpeed wiring > --> AeroElectric-List message posted by: Joel Harding > > Phil, > I'm trying to decide on the best way to implement Klaus's schematic > also. The question I have is, how important is the location of the > protection in a wire run. Lightspeed doesn't show the breaker location > in their drawing, but I assumed that since the breaker is the weak > point, it wouldn't make too much difference where it is located in the > line. Can someone clear this up for me? > > Joel Harding > On Tuesday, Jun 24, 2003, at 08:07 America/Denver, Phil Birkelbach > wrote: > > > --> AeroElectric-List message posted by: "Phil Birkelbach" > > > > > > Dan, > > > > That's exactly how I plan to wire mine up. The problem that I see from > > their wiring description is that long unprotected wire from the > > battery to > > the breaker. I'd rather get mine fused right away on the battery buss > > and > > then I can run the wire all over the place without having to worry > > about it. > > Their thought process may be circuit reliablitly by eliminating > > connections, > > but the system that you describe should prove to be very robust > > besides you > > have another ignition source. If I were putting in two EI's then I > > might > > try to figure out an alternate way to power the other one. Like one > > from > > the E-buss and one from the battery buss. > > > > Godspeed, > > > > Phil Birkelbach - Houston Texas > > RV-7 N727WB (Reserved) - Canopy > > http://www.myrv7.com > > > > ----- Original Message ----- > > From: "Dan Checkoway" > > To: > > Subject: AeroElectric-List: LightSpeed wiring > > > > > >> --> AeroElectric-List message posted by: "Dan Checkoway" > > > >> > >> Bob & folks, > >> > >> I'm installing a single LightSpeed Plasma II ignition in my RV-7 > >> (single > > EI, > >> single mag), and I'm considering straying slightly from the wiring > >> installation notes provided with the LSE system. > >> > >> They recommend wiring directly to and from the battery and using a > > pullable > >> breaker. Basically, positive battery terminal direct to a pullable 5A > >> breaker, then an optional on/off toggle switch, then the brain, then > >> wire > >> directly to the negative battery terminal. They recommend bypassing > > busses > >> in this manner. > >> > >> Here's what I would *like* to do instead: > >> > >> - power wired from a 5A fuse on the always-hot battery bus, which is > > roughly > >> 6" away (plus an inch or three) from the battery (+) terminal > >> - no pullable circuit breaker, let the 5A fuse do its job > >> - standard 1-3 ON/OFF toggle switch > >> - ground wired directly to the 48/24 firewall ground block, which is > >> connected to the battery via 5" of 2 AWG > >> > >> Do you see any potential gotchas in straying from LSE's > >> recommendations in > >> this way? I don't really see the purpose of using a pullable breaker > >> when > >> you use the optional on/off toggle switch and figure a fuse will do > >> fine. > > I > >> have control in normal cases, and the wires are protected. I guess I > > could > >> always use a 5A breaker switch, but again I don't really see the point > > when > >> a fuse will do the same job cheaper, lighter, etc. > >> > >> As far as the ground goes, is there any possibility of noise > >> affecting the > >> LightSpeed when ground is shared with every device in the plane, even > >> when > >> it's grounded so deliberately close to the battery (but not *quite* > >> to the > >> negative terminal)? > >> > >> Thanks, > >> )_( Dan > >> RV-7 N714D > >> http://www.rvproject.com > >> > >> > > > > > > _- > > ====================================================================== > > _- > > ====================================================================== > > _- > > ====================================================================== > > _- > > ====================================================================== > > > > > > ________________________________ Message 7 _____________________________________ Time: 09:35:48 AM PST US From: "Werner Schneider" Subject: Re: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: "Werner Schneider" Hello Phil, as close to the unprotected wire as possible, so if you connect to the Battery directly, then the link between the Battery and the fuse should be as short as possible, as this wire is not protected best regards Werner ----- Original Message ----- From: "Joel Harding" Subject: Re: AeroElectric-List: LightSpeed wiring > --> AeroElectric-List message posted by: Joel Harding > > Phil, > I'm trying to decide on the best way to implement Klaus's schematic > also. The question I have is, how important is the location of the > protection in a wire run. Lightspeed doesn't show the breaker location > in their drawing, but I assumed that since the breaker is the weak > point, it wouldn't make too much difference where it is located in the > line. Can someone clear this up for me? > > Joel Harding > On Tuesday, Jun 24, 2003, at 08:07 America/Denver, Phil Birkelbach > wrote: > > > --> AeroElectric-List message posted by: "Phil Birkelbach" > > > > > > Dan, > > > > That's exactly how I plan to wire mine up. The problem that I see from > > their wiring description is that long unprotected wire from the > > battery to > > the breaker. I'd rather get mine fused right away on the battery buss > > and > > then I can run the wire all over the place without having to worry > > about it. > > Their thought process may be circuit reliablitly by eliminating > > connections, > > but the system that you describe should prove to be very robust > > besides you > > have another ignition source. If I were putting in two EI's then I > > might > > try to figure out an alternate way to power the other one. Like one > > from > > the E-buss and one from the battery buss. > > > > Godspeed, > > > > Phil Birkelbach - Houston Texas > > RV-7 N727WB (Reserved) - Canopy > > http://www.myrv7.com > > > > ----- Original Message ----- > > From: "Dan Checkoway" > > To: > > Subject: AeroElectric-List: LightSpeed wiring > > > > > >> --> AeroElectric-List message posted by: "Dan Checkoway" > > > >> > >> Bob & folks, > >> > >> I'm installing a single LightSpeed Plasma II ignition in my RV-7 > >> (single > > EI, > >> single mag), and I'm considering straying slightly from the wiring > >> installation notes provided with the LSE system. > >> > >> They recommend wiring directly to and from the battery and using a > > pullable > >> breaker. Basically, positive battery terminal direct to a pullable 5A > >> breaker, then an optional on/off toggle switch, then the brain, then > >> wire > >> directly to the negative battery terminal. They recommend bypassing > > busses > >> in this manner. > >> > >> Here's what I would *like* to do instead: > >> > >> - power wired from a 5A fuse on the always-hot battery bus, which is > > roughly > >> 6" away (plus an inch or three) from the battery (+) terminal > >> - no pullable circuit breaker, let the 5A fuse do its job > >> - standard 1-3 ON/OFF toggle switch > >> - ground wired directly to the 48/24 firewall ground block, which is > >> connected to the battery via 5" of 2 AWG > >> > >> Do you see any potential gotchas in straying from LSE's > >> recommendations in > >> this way? I don't really see the purpose of using a pullable breaker > >> when > >> you use the optional on/off toggle switch and figure a fuse will do > >> fine. > > I > >> have control in normal cases, and the wires are protected. I guess I > > could > >> always use a 5A breaker switch, but again I don't really see the point > > when > >> a fuse will do the same job cheaper, lighter, etc. > >> > >> As far as the ground goes, is there any possibility of noise > >> affecting the > >> LightSpeed when ground is shared with every device in the plane, even > >> when > >> it's grounded so deliberately close to the battery (but not *quite* > >> to the > >> negative terminal)? > >> > >> Thanks, > >> )_( Dan > >> RV-7 N714D > >> http://www.rvproject.com > >> > >> > > > > > > _- > > ====================================================================== > > _- > > ====================================================================== > > _- > > ====================================================================== > > _- > > ====================================================================== > > > > > > ________________________________ Message 8 _____________________________________ Time: 09:45:04 AM PST US Subject: Re: AeroElectric-List: LightSpeed wiring From: "Matt Prather" --> AeroElectric-List message posted by: "Matt Prather" Joel, Where you put circuit protection is important. The further from your source of power that you place the breaker or fuse, the longer the run of wire which is essentially electrically unprotected. The integrity of that length of wire will be dependent on the mechanical protection provided by careful installation. Should vibration cause wire insulation to fail due to chafing in that unprotected section - especially on a metal airplane - that wire can become a fire starter/smoke producer. If the wire shorts to ground, the breaker/ fuse won't disconnect the circuit because it won't be carying any current. On the battery bus, you wouldn't have any way to turn it off. You would be stuck with having live with the smoke/fire until you decide to land, or possibly until the offending device burns itself out. The shorter the electrically unprotected runs, the better, because it is easier to provide robust mechanical installation. If you develop a mecanical failure in the protected section of the circuit which leads to a shorted power to ground situation, the electrical circuit protection can do its job. Regards, Matt- N34RD > --> AeroElectric-List message posted by: Joel Harding > > > Phil, > I'm trying to decide on the best way to implement Klaus's schematic > also. The question I have is, how important is the location of the > protection in a wire run. Lightspeed doesn't show the breaker location > in their drawing, but I assumed that since the breaker is the weak > point, it wouldn't make too much difference where it is located in the > line. Can someone clear this up for me? > > Joel Harding > On Tuesday, Jun 24, 2003, at 08:07 America/Denver, Phil Birkelbach > wrote: > >> --> AeroElectric-List message posted by: "Phil Birkelbach" >> >> >> Dan, >> >> That's exactly how I plan to wire mine up. The problem that I see >> from their wiring description is that long unprotected wire from the >> battery to >> the breaker. I'd rather get mine fused right away on the battery buss >> and >> then I can run the wire all over the place without having to worry snip ________________________________ Message 9 _____________________________________ Time: 09:57:19 AM PST US Subject: RE: AeroElectric-List: LightSpeed wiring From: "David" --> AeroElectric-List message posted by: "David" When I installed my Lightspeed Plasma II Plus I decided to ignore the instructions and wire to the regular power and ground bus. I found that the engine would turn over really well on the starter but wouldn't start until I released the start switch. The ignition was not getting enough volts during start. I rewired it direct to the battery (both power and ground) with a 10A(IIRC) fuse in the power lead at the battery to protect the wire a 5A fuse in a more accesible location. Now it starts properly. When you're planning the install consider voltage drops in both power and ground paths during start. -----Original Message----- From: Terry Watson [mailto:terry@tcwatson.com] Subject: RE: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: "Terry Watson" Light Speed's instructions say they want us to "route the positive power lead to a 5A pull-able breaker and then to the battery plus terminal, bypassing any electrical bus or master solenoid." And "If a toggle switch is used as an on/off switch, it should be installed next to the breaker." And also: "Route the negative lead directly to the battery ground terminal (not airframe ground buss) to avoid ignition noise...." I don't like the idea of running an unfused always hot line direct from the battery in the front baggage compartment floor on the right side of my RV-8A to the ignition toggles on the left side of the panel. I also don't like the idea of this one of a couple dozen circuits in the airplane going directly to both terminals of the battery; no battery buss, no ground buss; directly to the terminal. My inclination is to run it to a 5A fuse on a battery bus and ground it to a ground bus. Terry -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com]On Behalf Of Joel Harding Subject: Re: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: Joel Harding Phil, I'm trying to decide on the best way to implement Klaus's schematic also. The question I have is, how important is the location of the protection in a wire run. Lightspeed doesn't show the breaker location in their drawing, but I assumed that since the breaker is the weak point, it wouldn't make too much difference where it is located in the line. Can someone clear this up for me? Joel Harding On Tuesday, Jun 24, 2003, at 08:07 America/Denver, Phil Birkelbach wrote: > --> AeroElectric-List message posted by: "Phil Birkelbach" > > > Dan, > > That's exactly how I plan to wire mine up. The problem that I see from > their wiring description is that long unprotected wire from the > battery to > the breaker. I'd rather get mine fused right away on the battery buss > and > then I can run the wire all over the place without having to worry > about it. > Their thought process may be circuit reliablitly by eliminating > connections, > but the system that you describe should prove to be very robust > besides you > have another ignition source. If I were putting in two EI's then I > might > try to figure out an alternate way to power the other one. Like one > from > the E-buss and one from the battery buss. > > Godspeed, > > Phil Birkelbach - Houston Texas > RV-7 N727WB (Reserved) - Canopy > http://www.myrv7.com > > ----- Original Message ----- > From: "Dan Checkoway" > To: > Subject: AeroElectric-List: LightSpeed wiring > > >> --> AeroElectric-List message posted by: "Dan Checkoway" > >> >> Bob & folks, >> >> I'm installing a single LightSpeed Plasma II ignition in my RV-7 >> (single > EI, >> single mag), and I'm considering straying slightly from the wiring >> installation notes provided with the LSE system. >> >> They recommend wiring directly to and from the battery and using a > pullable >> breaker. Basically, positive battery terminal direct to a pullable 5A >> breaker, then an optional on/off toggle switch, then the brain, then >> wire >> directly to the negative battery terminal. They recommend bypassing > busses >> in this manner. >> >> Here's what I would *like* to do instead: >> >> - power wired from a 5A fuse on the always-hot battery bus, which is > roughly >> 6" away (plus an inch or three) from the battery (+) terminal >> - no pullable circuit breaker, let the 5A fuse do its job >> - standard 1-3 ON/OFF toggle switch >> - ground wired directly to the 48/24 firewall ground block, which is >> connected to the battery via 5" of 2 AWG >> >> Do you see any potential gotchas in straying from LSE's >> recommendations in >> this way? I don't really see the purpose of using a pullable breaker >> when >> you use the optional on/off toggle switch and figure a fuse will do >> fine. > I >> have control in normal cases, and the wires are protected. I guess I > could >> always use a 5A breaker switch, but again I don't really see the point > when >> a fuse will do the same job cheaper, lighter, etc. >> >> As far as the ground goes, is there any possibility of noise >> affecting the >> LightSpeed when ground is shared with every device in the plane, even >> when >> it's grounded so deliberately close to the battery (but not *quite* >> to the >> negative terminal)? >> >> Thanks, >> )_( Dan >> RV-7 N714D >> http://www.rvproject.com >> >> > > > _- > ====================================================================== > _- > ====================================================================== > _- > ====================================================================== > _- > ====================================================================== > > ________________________________ Message 10 ____________________________________ Time: 10:01:17 AM PST US From: "Phil Birkelbach" Subject: Re: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: "Phil Birkelbach" The location of the breaker in the line is VERY important. You want the circuit protection device (fuse or c/b) to be located as close to the buss as possible so that you don't have unprotected wiring going any further than is necessary. Imagine if you wired it up as Lightspeed suggests. Now you have this wire let's say it's 18AWG running from the battery to this circuit breaker that is located on the panel somewhere. This wire may be up to 8 feet in length or more. Now if you have a fault in that wire between the battery and the circuit breaker you have an unprotected wire that is pulling enough current to cause it's own failure and possibly the failure of other equipment and or wiring and possibly a fire. If the fuse is located very close to the battery now a fault in the wire will blow the fuse and the worst thing that would happen is your device would stop working. That is the function of a 'buss'. The 'hot' side of a buss (in this case a fuse block) is physically large enough that it can handle the full current that the battery is capable of producing. Now you put on the fuse and all of your current carrying medium is either big enough to handle it or protected by a device. Now about that battery buss. We use a 14AWG wire for that. It is not big enough to handle all the current that the battery can throw at it so we limit it's length to 6" or so. This way at least we are controlling how and where that wire will fail if it were to fault, and hopefully we don't locate it near other things that would be adversely effected by the heat generated by a wire that is failing and then we avoid using PVC coated wire so that it doesn't poison us as it melts. If you want to wire it up like Klaus suggests at least put a fusible link between the battery and the wire running to the circuit breaker, so you have some control over the failure mode. Personally I think Dan's way is better. Who needs a circuit breaker. Circuit breakers are for circuits that are going to nuisance trip and I think we can do a better job of designing these airplanes than that. Godspeed, Phil Birkelbach - Houston Texas RV-7 N727WB (Reserved) - Canopy http://www.myrv7.com ----- Original Message ----- From: "Joel Harding" Subject: Re: AeroElectric-List: LightSpeed wiring > --> AeroElectric-List message posted by: Joel Harding > > Phil, > I'm trying to decide on the best way to implement Klaus's schematic > also. The question I have is, how important is the location of the > protection in a wire run. Lightspeed doesn't show the breaker location > in their drawing, but I assumed that since the breaker is the weak > point, it wouldn't make too much difference where it is located in the > line. Can someone clear this up for me? > > Joel Harding > On Tuesday, Jun 24, 2003, at 08:07 America/Denver, Phil Birkelbach > wrote: > > > --> AeroElectric-List message posted by: "Phil Birkelbach" > > > > > > Dan, > > > > That's exactly how I plan to wire mine up. The problem that I see from > > their wiring description is that long unprotected wire from the > > battery to > > the breaker. I'd rather get mine fused right away on the battery buss > > and > > then I can run the wire all over the place without having to worry > > about it. > > Their thought process may be circuit reliablitly by eliminating > > connections, > > but the system that you describe should prove to be very robust > > besides you > > have another ignition source. If I were putting in two EI's then I > > might > > try to figure out an alternate way to power the other one. Like one > > from > > the E-buss and one from the battery buss. > > > > Godspeed, > > > > Phil Birkelbach - Houston Texas > > RV-7 N727WB (Reserved) - Canopy > > http://www.myrv7.com > > > > ----- Original Message ----- > > From: "Dan Checkoway" > > To: > > Subject: AeroElectric-List: LightSpeed wiring > > > > > >> --> AeroElectric-List message posted by: "Dan Checkoway" > > > >> > >> Bob & folks, > >> > >> I'm installing a single LightSpeed Plasma II ignition in my RV-7 > >> (single > > EI, > >> single mag), and I'm considering straying slightly from the wiring > >> installation notes provided with the LSE system. > >> > >> They recommend wiring directly to and from the battery and using a > > pullable > >> breaker. Basically, positive battery terminal direct to a pullable 5A > >> breaker, then an optional on/off toggle switch, then the brain, then > >> wire > >> directly to the negative battery terminal. They recommend bypassing > > busses > >> in this manner. > >> > >> Here's what I would *like* to do instead: > >> > >> - power wired from a 5A fuse on the always-hot battery bus, which is > > roughly > >> 6" away (plus an inch or three) from the battery (+) terminal > >> - no pullable circuit breaker, let the 5A fuse do its job > >> - standard 1-3 ON/OFF toggle switch > >> - ground wired directly to the 48/24 firewall ground block, which is > >> connected to the battery via 5" of 2 AWG > >> > >> Do you see any potential gotchas in straying from LSE's > >> recommendations in > >> this way? I don't really see the purpose of using a pullable breaker > >> when > >> you use the optional on/off toggle switch and figure a fuse will do > >> fine. > > I > >> have control in normal cases, and the wires are protected. I guess I > > could > >> always use a 5A breaker switch, but again I don't really see the point > > when > >> a fuse will do the same job cheaper, lighter, etc. > >> > >> As far as the ground goes, is there any possibility of noise > >> affecting the > >> LightSpeed when ground is shared with every device in the plane, even > >> when > >> it's grounded so deliberately close to the battery (but not *quite* > >> to the > >> negative terminal)? > >> > >> Thanks, > >> )_( Dan > >> RV-7 N714D > >> http://www.rvproject.com > >> > >> > > > > > > _- > > ====================================================================== > > _- > > ====================================================================== > > _- > > ====================================================================== > > _- > > ====================================================================== > > > > > > ________________________________ Message 11 ____________________________________ Time: 10:31:14 AM PST US Subject: RE: AeroElectric-List: LightSpeed wiring From: "I-Blackler, Wayne R" --> AeroElectric-List message posted by: "I-Blackler, Wayne R" I have dual Lightspeed units (Plamsa I and III) in my Z-14 wired IO-360 powered Long EZ. Being a composite aeroplane (like Klaus Savier's aircraft) I consider the ground wiring to be the most important in my aircraft for EVERYTHING electrical EXCEPT Ignition. I want to decrease failure modes as much as I can, including during and after maintenance. I am running power direct from the batts (main and aux to left and right ignitions), to 5A switch type circuit breakers to the Lightspeed boxes. The ground runs back to the respective batteries as well. The wiring is separate from everything else, and runs in the most damage tolerant path in my aeroplane. If things turn to worms I have 17Ahr a side to run my ignition. No reliance on anything but a battery. No problems with failed electrical system components. The circuit breaker/switch allows me to (albeit expensively) switch the IGN on/off. Minimum breaks. Why put half a dozen failure points (some remote I know) between power to your ignition? - Wayne Blackler ________________________________ Message 12 ____________________________________ Time: 12:22:11 PM PST US Subject: Re: AeroElectric-List: LightSpeed wiring From: Joel Harding --> AeroElectric-List message posted by: Joel Harding Thanks for the education guys. Since I've already installed the breakers, I think I'll go the fuse link route. One thing that led me to ask the question, was the fact that figures Z13 and Z11 have the 5 A field breaker in different locations. I understand now that with the fuse link, the location of the breaker isn't as important. One variation that I've noticed is that while Lightspeed is calling for a 3A breaker for a four cylinder engine in my instructions, most of the responders are indicating the use of a 5 A breaker. Could you explain the reason for the change? Thanks, Joel Harding On Tuesday, Jun 24, 2003, at 10:58 America/Denver, Phil Birkelbach wrote: > --> AeroElectric-List message posted by: "Phil Birkelbach" > > > The location of the breaker in the line is VERY important. You want > the > circuit protection device (fuse or c/b) to be located as close to the > buss > as possible so that you don't have unprotected wiring going any > further than > is necessary. Imagine if you wired it up as Lightspeed suggests. Now > you > have this wire let's say it's 18AWG running from the battery to this > circuit > breaker that is located on the panel somewhere. This wire may be up > to 8 > feet in length or more. Now if you have a fault in that wire between > the > battery and the circuit breaker you have an unprotected wire that is > pulling > enough current to cause it's own failure and possibly the failure of > other > equipment and or wiring and possibly a fire. If the fuse is located > very > close to the battery now a fault in the wire will blow the fuse and the > worst thing that would happen is your device would stop working. > > That is the function of a 'buss'. The 'hot' side of a buss (in this > case a > fuse block) is physically large enough that it can handle the full > current > that the battery is capable of producing. Now you put on the fuse and > all > of your current carrying medium is either big enough to handle it or > protected by a device. Now about that battery buss. We use a 14AWG > wire > for that. It is not big enough to handle all the current that the > battery > can throw at it so we limit it's length to 6" or so. This way at > least we > are controlling how and where that wire will fail if it were to fault, > and > hopefully we don't locate it near other things that would be adversely > effected by the heat generated by a wire that is failing and then we > avoid > using PVC coated wire so that it doesn't poison us as it melts. > > If you want to wire it up like Klaus suggests at least put a fusible > link > between the battery and the wire running to the circuit breaker, so > you have > some control over the failure mode. Personally I think Dan's way is > better. > Who needs a circuit breaker. Circuit breakers are for circuits that > are > going to nuisance trip and I think we can do a better job of designing > these > airplanes than that. > > Godspeed, > > Phil Birkelbach - Houston Texas > RV-7 N727WB (Reserved) - Canopy > http://www.myrv7.com > > ----- Original Message ----- > From: "Joel Harding" > To: > Subject: Re: AeroElectric-List: LightSpeed wiring > > >> --> AeroElectric-List message posted by: Joel Harding > >> >> Phil, >> I'm trying to decide on the best way to implement Klaus's schematic >> also. The question I have is, how important is the location of the >> protection in a wire run. Lightspeed doesn't show the breaker location >> in their drawing, but I assumed that since the breaker is the weak >> point, it wouldn't make too much difference where it is located in the >> line. Can someone clear this up for me? >> >> Joel Harding >> On Tuesday, Jun 24, 2003, at 08:07 America/Denver, Phil Birkelbach >> wrote: >> >>> --> AeroElectric-List message posted by: "Phil Birkelbach" >>> >>> >>> Dan, >>> >>> That's exactly how I plan to wire mine up. The problem that I see >>> from >>> their wiring description is that long unprotected wire from the >>> battery to >>> the breaker. I'd rather get mine fused right away on the battery >>> buss >>> and >>> then I can run the wire all over the place without having to worry >>> about it. >>> Their thought process may be circuit reliablitly by eliminating >>> connections, >>> but the system that you describe should prove to be very robust >>> besides you >>> have another ignition source. If I were putting in two EI's then I >>> might >>> try to figure out an alternate way to power the other one. Like one >>> from >>> the E-buss and one from the battery buss. >>> >>> Godspeed, >>> >>> Phil Birkelbach - Houston Texas >>> RV-7 N727WB (Reserved) - Canopy >>> http://www.myrv7.com >>> >>> ----- Original Message ----- >>> From: "Dan Checkoway" >>> To: >>> Subject: AeroElectric-List: LightSpeed wiring >>> >>> >>>> --> AeroElectric-List message posted by: "Dan Checkoway" >>> >>>> >>>> Bob & folks, >>>> >>>> I'm installing a single LightSpeed Plasma II ignition in my RV-7 >>>> (single >>> EI, >>>> single mag), and I'm considering straying slightly from the wiring >>>> installation notes provided with the LSE system. >>>> >>>> They recommend wiring directly to and from the battery and using a >>> pullable >>>> breaker. Basically, positive battery terminal direct to a pullable >>>> 5A >>>> breaker, then an optional on/off toggle switch, then the brain, then >>>> wire >>>> directly to the negative battery terminal. They recommend bypassing >>> busses >>>> in this manner. >>>> >>>> Here's what I would *like* to do instead: >>>> >>>> - power wired from a 5A fuse on the always-hot battery bus, which is >>> roughly >>>> 6" away (plus an inch or three) from the battery (+) terminal >>>> - no pullable circuit breaker, let the 5A fuse do its job >>>> - standard 1-3 ON/OFF toggle switch >>>> - ground wired directly to the 48/24 firewall ground block, which is >>>> connected to the battery via 5" of 2 AWG >>>> >>>> Do you see any potential gotchas in straying from LSE's >>>> recommendations in >>>> this way? I don't really see the purpose of using a pullable >>>> breaker >>>> when >>>> you use the optional on/off toggle switch and figure a fuse will do >>>> fine. >>> I >>>> have control in normal cases, and the wires are protected. I guess >>>> I >>> could >>>> always use a 5A breaker switch, but again I don't really see the >>>> point >>> when >>>> a fuse will do the same job cheaper, lighter, etc. >>>> >>>> As far as the ground goes, is there any possibility of noise >>>> affecting the >>>> LightSpeed when ground is shared with every device in the plane, >>>> even >>>> when >>>> it's grounded so deliberately close to the battery (but not *quite* >>>> to the >>>> negative terminal)? >>>> >>>> Thanks, >>>> )_( Dan >>>> RV-7 N714D >>>> http://www.rvproject.com >>>> >>>> >>> >>> >>> _- >>> ===================================================================== >>> >>> _- >>> ===================================================================== >>> >>> _- >>> ===================================================================== >>> >>> _- >>> ===================================================================== >>> >>> >>> >> >> > > > _- > ====================================================================== > _- > ====================================================================== > _- > ====================================================================== > _- > ====================================================================== > > ________________________________ Message 13 ____________________________________ Time: 02:41:19 PM PST US From: "Fergus Kyle" Subject: AeroElectric-List: LEDs --> AeroElectric-List message posted by: "Fergus Kyle" ----- Original Message ----- From: "Jos Okhuijsen" Subject: AeroElectric-List: Is the E-Bus that Essential? --> AeroElectric-List message posted by: Robert Whitaker Gang, Up to this point, I have been planning to wire up my RV-9 according to Fig. Z-11A. My understanding is the essential bus would be used to conserve power during an alternator out condition. However, almost all of the things that I plan to hang off of the main power distribution bus are switched. Therefore, I could turn off the "non-essential" equipment to conserve battery capacity. This being the case, do I need an E-bus? I'm probably missing another good reason for wiring up a separate E-bus as shown on Fig. Z-11A. Please shoot holes in my logic before I shoot a hole in my foot! Rob ________________________________ Message 15 ____________________________________ Time: 03:47:02 PM PST US Subject: Re: AeroElectric-List: Is the E-Bus that Essential? From: "Matt Prather" --> AeroElectric-List message posted by: "Matt Prather" Rob, One benefit of the e-bus which has been identified in the past is related to operational concerns. If the alternator dies on you, turn on the e-bus alternate feed, turn off the master, and you are down to your minimum load condition in easy to remember steps. This is good, should you have forgotten to turn off your collision avoidance lights, or are in the bumps with lots of stuff going on around you. If you are slick laying out the panel, you can set it up so that normal condition is to have both bus control switch 'up.' (maybe placed next to each other) This turns the alternator and battery on and the e-bus alternate feed off. The endurance mode has both switches 'down.' This turns off the alternator field and battery relay (and other non- essentials), and closes the alternate feed connection for the e-bus. The only disadvantage to this arrangement that I can see is that to completely unpower the ship, the e-bus swith is in the 'up' position, and the master is in the 'down' position. I might live with that since its easier to be deliberate about switch settings when you are sitting on the ground. You could argue the panel logic either way, but I still think there is a benefit to only having two switches to worry about. Another benefit of the e-bus is that it allows you to save the power drain associated with the relay that connects the main bus to the battery. This is so because the e-bus can alternately be powered by a direct switch which is allowed for by the small loads designed for. That lets you either have better endurance, or carry a smaller battery with the same endurance margin. Regards, Matt- N34RD > --> AeroElectric-List message posted by: Robert Whitaker > > > Gang, > > Up to this point, I have been planning to wire up my RV-9 > according to Fig. Z-11A. My understanding is the essential > bus would be used to conserve power during an alternator out > condition. > > However, almost all of the things that I plan to hang off of the > main power distribution bus are switched. Therefore, I could > turn off the "non-essential" equipment to conserve battery > capacity. This being the case, do I need an E-bus? > > I'm probably missing another good reason for wiring up a > separate E-bus as shown on Fig. Z-11A. > > Please shoot holes in my logic before I shoot a hole in > my foot! > > Rob > > ________________________________ Message 16 ____________________________________ Time: 04:07:21 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Is the E-Bus that Essential? --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 03:52 PM 6/24/2003 -0600, you wrote: >--> AeroElectric-List message posted by: Robert Whitaker > >Gang, > >Up to this point, I have been planning to wire up my RV-9 >according to Fig. Z-11A. My understanding is the essential >bus would be used to conserve power during an alternator out >condition. > >However, almost all of the things that I plan to hang off of the >main power distribution bus are switched. Therefore, I could >turn off the "non-essential" equipment to conserve battery >capacity. This being the case, do I need an E-bus? > >I'm probably missing another good reason for wiring up a >separate E-bus as shown on Fig. Z-11A. > >Please shoot holes in my logic before I shoot a hole in >my foot! There has been a lot written about this . . . in fact, the bus is more properly called the "endurance" bus. Check out chapter 17 of the 'Connection which you can download at http://www.aeroelectric.com/articles/Rev9/ch17-9.pdf By the way, Mr. Martin Gomez (who was so kind as to share his experience with us) was told that I'd used his story as but one of multitudinous illustrations of how certified systems architecture and mind-set boxes us into stupid and unnecessary situations. I invited him to read the chapter cited above. He contacted me again later and offer the following: I just read the chapter. You were right on! I often thought before and after my little fiasco that our electrical systems were fine in the days when the Piper J-3 was a typical light airplane. Now that we expect to fly in miserable weather, relying on our avionics, it's nuts to still have the same electrical system. I, too, am an engineer (BS in aero, M.Eng. in EE, MS in Applied Physics), with 20 years of experience. Of that, 9 was at a UAV company. We once lost a UAV because of an alternator overvoltage...3 years after my emergency, and after I had implored the avionics designers to split the bus in two. One of my hobbies is that I collect flight manuals for airplanes that I'll never get to fly, including jet fighters, airliners, etc. They do NOT put all their eggs in one basket. It seems silly to have two radios (say) and put both on the same bus so that one failure can zap them both. I am indeed considering building an airplane. My current choice is an RV-7. And you can bet that it will have a non- standard electrical system! In fact, it was on the Van's Airforce Yahoo group that I learned about you, and was told that you used my AOPA article. I would love a copy of your book, but if I'm going to benefit from your experience, I ought to pay for it. Regards, Martin Martin Gomezmlg28@cornell.edu A day later his order came in for the book. The e-buss is more than load reduction . . . it's a DUAL path distribution structure to keep minimal en-route operational equipment going until airport is in sight and do it battery-only for duration of fuel aboard. Bob . . . ________________________________ Message 17 ____________________________________ Time: 04:29:07 PM PST US From: Kevin Horton Subject: Re: AeroElectric-List: Is the E-Bus that Essential? --> AeroElectric-List message posted by: Kevin Horton >--> AeroElectric-List message posted by: Robert Whitaker > >Gang, > >Up to this point, I have been planning to wire up my RV-9 >according to Fig. Z-11A. My understanding is the essential >bus would be used to conserve power during an alternator out >condition. > >However, almost all of the things that I plan to hang off of the >main power distribution bus are switched. Therefore, I could >turn off the "non-essential" equipment to conserve battery >capacity. This being the case, do I need an E-bus? > >I'm probably missing another good reason for wiring up a >separate E-bus as shown on Fig. Z-11A. > >Please shoot holes in my logic before I shoot a hole in >my foot! > >Rob Over and above the stuff mentioned by Matt Prather, the E-bus also provides a more reliable power supply for the really important stuff, as it has a separate power feed. So there are some failures that might kill the power to the main bus, but you could select the E-bus alternate feed and get power to the E-bus. You'll have to decide how important it is to keep some things powered. If the aircraft design and the way you fly it mean that a total electrical failure would be a non-event, then the E-bus is probably overkill for you. If you want to maximize the probability of some items receiving power, even after single failures, then the E-bus might be a good idea for you. -- Kevin Horton RV-8 (finishing kit) Ottawa, Canada http://go.phpwebhosting.com/~khorton/rv8/ ________________________________ Message 18 ____________________________________ Time: 04:47:50 PM PST US From: "Phil Birkelbach" Subject: Re: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: "Phil Birkelbach" As with all electrical distribution circuits the fuse or circuit breaker is there to protect the wire. It has nothing to do with the end device that is on that circuit. You size the wire big enough to supply power to the device and then size the breaker / fuse to protect the wire. I imagine that a 5A breaker is also easier to find than a 3A. Godspeed, Phil Birkelbach - Houston Texas RV-7 N727WB (Reserved) - Canopy http://www.myrv7.com ----- Original Message ----- From: "Joel Harding" Subject: Re: AeroElectric-List: LightSpeed wiring > --> AeroElectric-List message posted by: Joel Harding > > Thanks for the education guys. Since I've already installed the > breakers, I think I'll go the fuse link route. > One thing that led me to ask the question, was the fact that figures > Z13 and Z11 have the 5 A field breaker in different locations. I > understand now that with the fuse link, the location of the breaker > isn't as important. > One variation that I've noticed is that while Lightspeed is calling for > a 3A breaker for a four cylinder engine in my instructions, most of the > responders are indicating the use of a 5 A breaker. Could you explain > the reason for the change? > > Thanks, > > Joel Harding > On Tuesday, Jun 24, 2003, at 10:58 America/Denver, Phil Birkelbach > wrote: > > > --> AeroElectric-List message posted by: "Phil Birkelbach" > > > > > > The location of the breaker in the line is VERY important. You want > > the > > circuit protection device (fuse or c/b) to be located as close to the > > buss > > as possible so that you don't have unprotected wiring going any > > further than > > is necessary. Imagine if you wired it up as Lightspeed suggests. Now > > you > > have this wire let's say it's 18AWG running from the battery to this > > circuit > > breaker that is located on the panel somewhere. This wire may be up > > to 8 > > feet in length or more. Now if you have a fault in that wire between > > the > > battery and the circuit breaker you have an unprotected wire that is > > pulling > > enough current to cause it's own failure and possibly the failure of > > other > > equipment and or wiring and possibly a fire. If the fuse is located > > very > > close to the battery now a fault in the wire will blow the fuse and the > > worst thing that would happen is your device would stop working. > > > > That is the function of a 'buss'. The 'hot' side of a buss (in this > > case a > > fuse block) is physically large enough that it can handle the full > > current > > that the battery is capable of producing. Now you put on the fuse and > > all > > of your current carrying medium is either big enough to handle it or > > protected by a device. Now about that battery buss. We use a 14AWG > > wire > > for that. It is not big enough to handle all the current that the > > battery > > can throw at it so we limit it's length to 6" or so. This way at > > least we > > are controlling how and where that wire will fail if it were to fault, > > and > > hopefully we don't locate it near other things that would be adversely > > effected by the heat generated by a wire that is failing and then we > > avoid > > using PVC coated wire so that it doesn't poison us as it melts. > > > > If you want to wire it up like Klaus suggests at least put a fusible > > link > > between the battery and the wire running to the circuit breaker, so > > you have > > some control over the failure mode. Personally I think Dan's way is > > better. > > Who needs a circuit breaker. Circuit breakers are for circuits that > > are > > going to nuisance trip and I think we can do a better job of designing > > these > > airplanes than that. > > > > Godspeed, > > > > Phil Birkelbach - Houston Texas > > RV-7 N727WB (Reserved) - Canopy > > http://www.myrv7.com > > > > ----- Original Message ----- > > From: "Joel Harding" > > To: > > Subject: Re: AeroElectric-List: LightSpeed wiring > > > > > >> --> AeroElectric-List message posted by: Joel Harding > > > >> > >> Phil, > >> I'm trying to decide on the best way to implement Klaus's schematic > >> also. The question I have is, how important is the location of the > >> protection in a wire run. Lightspeed doesn't show the breaker location > >> in their drawing, but I assumed that since the breaker is the weak > >> point, it wouldn't make too much difference where it is located in the > >> line. Can someone clear this up for me? > >> > >> Joel Harding > >> On Tuesday, Jun 24, 2003, at 08:07 America/Denver, Phil Birkelbach > >> wrote: > >> > >>> --> AeroElectric-List message posted by: "Phil Birkelbach" > >>> > >>> > >>> Dan, > >>> > >>> That's exactly how I plan to wire mine up. The problem that I see > >>> from > >>> their wiring description is that long unprotected wire from the > >>> battery to > >>> the breaker. I'd rather get mine fused right away on the battery > >>> buss > >>> and > >>> then I can run the wire all over the place without having to worry > >>> about it. > >>> Their thought process may be circuit reliablitly by eliminating > >>> connections, > >>> but the system that you describe should prove to be very robust > >>> besides you > >>> have another ignition source. If I were putting in two EI's then I > >>> might > >>> try to figure out an alternate way to power the other one. Like one > >>> from > >>> the E-buss and one from the battery buss. > >>> > >>> Godspeed, > >>> > >>> Phil Birkelbach - Houston Texas > >>> RV-7 N727WB (Reserved) - Canopy > >>> http://www.myrv7.com > >>> > >>> ----- Original Message ----- > >>> From: "Dan Checkoway" > >>> To: > >>> Subject: AeroElectric-List: LightSpeed wiring > >>> > >>> > >>>> --> AeroElectric-List message posted by: "Dan Checkoway" > >>> > >>>> > >>>> Bob & folks, > >>>> > >>>> I'm installing a single LightSpeed Plasma II ignition in my RV-7 > >>>> (single > >>> EI, > >>>> single mag), and I'm considering straying slightly from the wiring > >>>> installation notes provided with the LSE system. > >>>> > >>>> They recommend wiring directly to and from the battery and using a > >>> pullable > >>>> breaker. Basically, positive battery terminal direct to a pullable > >>>> 5A > >>>> breaker, then an optional on/off toggle switch, then the brain, then > >>>> wire > >>>> directly to the negative battery terminal. They recommend bypassing > >>> busses > >>>> in this manner. > >>>> > >>>> Here's what I would *like* to do instead: > >>>> > >>>> - power wired from a 5A fuse on the always-hot battery bus, which is > >>> roughly > >>>> 6" away (plus an inch or three) from the battery (+) terminal > >>>> - no pullable circuit breaker, let the 5A fuse do its job > >>>> - standard 1-3 ON/OFF toggle switch > >>>> - ground wired directly to the 48/24 firewall ground block, which is > >>>> connected to the battery via 5" of 2 AWG > >>>> > >>>> Do you see any potential gotchas in straying from LSE's > >>>> recommendations in > >>>> this way? I don't really see the purpose of using a pullable > >>>> breaker > >>>> when > >>>> you use the optional on/off toggle switch and figure a fuse will do > >>>> fine. > >>> I > >>>> have control in normal cases, and the wires are protected. I guess > >>>> I > >>> could > >>>> always use a 5A breaker switch, but again I don't really see the > >>>> point > >>> when > >>>> a fuse will do the same job cheaper, lighter, etc. > >>>> > >>>> As far as the ground goes, is there any possibility of noise > >>>> affecting the > >>>> LightSpeed when ground is shared with every device in the plane, > >>>> even > >>>> when > >>>> it's grounded so deliberately close to the battery (but not *quite* > >>>> to the > >>>> negative terminal)? > >>>> > >>>> Thanks, > >>>> )_( Dan > >>>> RV-7 N714D > >>>> http://www.rvproject.com > >>>> > >>>> > >>> > >>> > >>> _- > >>> ===================================================================== > >>> >>> _- > >>> ===================================================================== > >>> >>> _- > >>> ===================================================================== > >>> >>> _- > >>> ===================================================================== > >>> >>> > >>> > >> > >> > > > > > > _- > > ====================================================================== > > _- > > ====================================================================== > > _- > > ====================================================================== > > _- > > ====================================================================== > > > > > > ________________________________ Message 19 ____________________________________ Time: 05:18:46 PM PST US From: "Phil Birkelbach" Subject: Re: AeroElectric-List: Is the E-Bus that Essential? --> AeroElectric-List message posted by: "Phil Birkelbach" Don't forget that by running the E-buss on alternate feed and having the master switch off you don't sacrifice a whole amp of current to keep the battery contactor closed. Godspeed, Phil ----- Original Message ----- From: "Kevin Horton" Subject: Re: AeroElectric-List: Is the E-Bus that Essential? > --> AeroElectric-List message posted by: Kevin Horton > > >--> AeroElectric-List message posted by: Robert Whitaker > > > >Gang, > > > >Up to this point, I have been planning to wire up my RV-9 > >according to Fig. Z-11A. My understanding is the essential > >bus would be used to conserve power during an alternator out > >condition. > > > >However, almost all of the things that I plan to hang off of the > >main power distribution bus are switched. Therefore, I could > >turn off the "non-essential" equipment to conserve battery > >capacity. This being the case, do I need an E-bus? > > > >I'm probably missing another good reason for wiring up a > >separate E-bus as shown on Fig. Z-11A. > > > >Please shoot holes in my logic before I shoot a hole in > >my foot! > > > >Rob > > Over and above the stuff mentioned by Matt Prather, the E-bus also > provides a more reliable power supply for the really important stuff, > as it has a separate power feed. So there are some failures that > might kill the power to the main bus, but you could select the E-bus > alternate feed and get power to the E-bus. > > You'll have to decide how important it is to keep some things > powered. If the aircraft design and the way you fly it mean that a > total electrical failure would be a non-event, then the E-bus is > probably overkill for you. If you want to maximize the probability > of some items receiving power, even after single failures, then the > E-bus might be a good idea for you. > -- > Kevin Horton RV-8 (finishing kit) > Ottawa, Canada > http://go.phpwebhosting.com/~khorton/rv8/ > > ________________________________ Message 20 ____________________________________ Time: 07:02:05 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 03:34 PM 6/23/2003 -0700, you wrote: >--> AeroElectric-List message posted by: "Dan Checkoway" > >Bob & folks, > >I'm installing a single LightSpeed Plasma II ignition in my RV-7 (single EI, >single mag), and I'm considering straying slightly from the wiring >installation notes provided with the LSE system.\ Wiring diagrams from most manufacturer's assume that your electrical system is a spam-can-clone . . . >They recommend wiring directly to and from the battery and using a pullable >breaker. Basically, positive battery terminal direct to a pullable 5A >breaker, then an optional on/off toggle switch, then the brain, then wire >directly to the negative battery terminal. They recommend bypassing busses >in this manner. If you have an electrically dependent engine, then there's no reason NOT to run engine support system from an always-hot battery bus. If you have dual support systems (two pumps one of which MUST run to keep flying and/or dual ignition systems) then there's no reason not to have two batteries, each with its own battery bus to support half the engine hardware. Fuses/breakers AT the battery bus take care of all necessary protection. NOISE doesn't swap between systems because they share grounds, it propagates because they are badly wired to multiple grounds. See chapter on noise in the 'Connection. Bob . . . ________________________________ Message 21 ____________________________________ Time: 07:03:22 PM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: LightSpeed wiring --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 09:04 AM 6/24/2003 -0700, you wrote: >--> AeroElectric-List message posted by: "Terry Watson" > >Light Speed's instructions say they want us to "route the positive power >lead to a 5A pull-able breaker and then to the battery plus terminal, >bypassing any electrical bus or master solenoid." And "If a toggle switch is >used as an on/off switch, it should be installed next to the breaker." And >also: "Route the negative lead directly to the battery ground terminal (not >airframe ground buss) to avoid ignition noise...." This is BS on all counts . . . Bob . . . ________________________________ Message 22 ____________________________________ Time: 07:38:26 PM PST US From: CardinalNSB@aol.com Subject: AeroElectric-List: Re: isolated ground wire for avionics in metal airplane --> AeroElectric-List message posted by: CardinalNSB@aol.com Would I see any benefit or detriment to using a dedicated ground wire for my avionics in my metal airplane, isolated from the metal airframe? Thanks, Skip