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Tundra10

Joined: 14 Jun 2010
Posts: 102
Location: Scarborough, Ontario

Posted: Thu Nov 18, 2010 10:32 pm Post subject: Z13/8 Rev Q comments

Bob,



I wonder why the feed paths to the Endurance Bus are different.  The  

relay from the battery bus is 14 awg and fused, while the diode from  

the main power bus is 16 awg and not fused.



Previously, I was planning to use 14 awg and * 6 inches or less wire,  

without any fuses for both paths.  I have changed my drawing so both  

paths include fuses.



Since Z13/8 highlights some new technology with E-Mags, perhaps it  

makes sense to replace the Ford regulator with an electronic one that  

includes overvoltage protection and low voltage annunication ?



Jeff Page

Dream Aircraft Tundra #10

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Nov 19, 2010 4:08 pm Post subject: Z13/8 Rev Q comments

At 12:15 AM 11/19/2010, you wrote:

 	  Quote: 	
		  



Bob,



I wonder why the feed paths to the Endurance Bus are different.  The

relay from the battery bus is 14 awg and fused, while the diode from

the main power bus is 16 awg and not fused.


	


   Good question. The 16AWG wires are adequate to the

   current carrying task assigned to power the e-bus

   and you'll note that they're called out as "short"

   wires.  As "short", potentially sacrificial wires,

   we'd like them to fuse open as fast as practical,

   hence make them as small as practical. As we discovered

   in this experiment on the bench some time back . . .



http://aeroelectric.com/Pictures/Wire/22AWG_20A.pdf



   . . . a 20 AMP current through a 22AWG wire didn't

   warm it enough to put the 150C insulation at risk.

   So we could probably wire the short normal feed path

   with 20 or even 18 AWG without 'over stressing' the

   the wire.



   An e-bus configured to the original idea calls for

   punching through a cloud layer at the home airport,

   failing an alternator, and flying comfortably to

   airport of intended destination battery only. This

   called for getting alternator-out endurance-bus loads

   down to 2 or 3 amps. Not an terribly difficult task in

   the magneto/steam-gage era.



   Then came electrically dependent engines and

   clusters of panel mounted 'stuff' that increased

   the size of a 'minimalist' power requirement.

   Okay, add the SD-8 and we've got 8-10 amps of

   continuous load without depleting the battery.



   Figure 2-3 amps of the original concept on top

   of that and one COULD consider an e-bus load of

   perhaps 13 amps.  Okay, the feeders had to take

   a big jump in AWG. Hence the fat feeder

   for alternate feed path. If we're to observe

   the reverence for crash safety and limit always

   hot feeders to 7A or less, then the S704 relay

   gets added and the fuse sizes go up to accommodate

   the new definition of endurance loads.



   This illustrates the thinking behind the disparity

   between normal and alternate feed wire sizes.



 	  Quote: 	
		  Previously, I was planning to use 14 awg and * 6 inches or less wire,

without any fuses for both paths.


	


   How did you arrive at this? When the battery and main

   bus fuse blocks are immediately adjacent to each other,

   then the no-fuse, 16AWG feeders (or even smaller

   as described above) through the diode fits legacy

   design goals. But the feeder from the battery

   bus to the e-bus is a long conductor that classically

   gets either:



   (1) 7A or less protection for skinny feeder and no

   remote mini-contactor or



   (2) a larger feeder and contactor per Z-32. The larger

   14AWG wire is appropriate for low voltage drop on longer

   wires good for up to 15A and rear mounted batteries. If

   your battery is up front, that wire could comfortably

   drop to 12AWG.

 	  Quote: 	
		  I have changed my drawing so both paths include fuses.


	


   Doen't hurt . . . but not necessary by legacy design

   goals.

 	  Quote: 	
		  Since Z13/8 highlights some new technology with E-Mags, perhaps it

makes sense to replace the Ford regulator with an electronic one that

includes overvoltage protection and low voltage annunication ?


	


   As suggested in an earlier post, you are encouraged

   to consider the full constellation of available accessories

   to put frosting on the Z-13/8 cake. I doubt that no two

   OBAM airplanes flying this ARCHITECTURE have the same

   frosting. It's my personal goal to suggest the simplest,

   lowest cost suite of components that get the job done.

   If the builder's design goals and pocket-book goes beyond

   those suggestions, great!



   Bob . . .

Tundra10

Joined: 14 Jun 2010
Posts: 102
Location: Scarborough, Ontario

Posted: Sun Nov 21, 2010 8:28 am Post subject: Z13/8 Rev Q comments

Robert L. Nuckolls wrote:

    Figure 2-3 amps of the original concept on top

    of that and one COULD consider an e-bus load of

    perhaps 13 amps.  Okay, the feeders had to take

    a big jump in AWG. Hence the fat feeder

    for alternate feed path. If we're to observe

    the reverence for crash safety and limit always

    hot feeders to 7A or less, then the S704 relay

    gets added and the fuse sizes go up to accommodate

    the new definition of endurance loads.



    This illustrates the thinking behind the disparity

    between normal and alternate feed wire sizes.



Whether the feed is via the diode or the relay, the load is the same.   

Shouldn't the wire capacity be the same ?

 	  Quote: 	
		   Previously, I was planning to use 14 awg and * 6 inches or less wire,

 without any fuses for both paths.


	


    How did you arrive at this? When the battery and main

    bus fuse blocks are immediately adjacent to each other,

    then the no-fuse, 16AWG feeders (or even smaller

    as described above) through the diode fits legacy

    design goals. But the feeder from the battery

    bus to the e-bus is a long conductor that classically

    gets either:



    (1) 7A or less protection for skinny feeder and no

    remote mini-contactor or



    (2) a larger feeder and contactor per Z-32. The larger

    14AWG wire is appropriate for low voltage drop on longer

    wires good for up to 15A and rear mounted batteries. If

    your battery is up front, that wire could comfortably

    drop to 12AWG.



My battery will be on the front of the firewall.  I planned the  

connections between busses, contactors and relays all to be less than  

6", so I originally omitted fuses.  I am minimizing my inventory by  

purchasing only 14, 18 and 22 gauge wire, since the numbers worked out  

that I would rarely need 16 and 20 gauge wire.  So the 16 awg feeders  

changed to 14 awg.



Since my busses will be fuse blocks, it is quite easy to use one of  

the fuse positions to feed the bus.  However, I would prefer fewer  

connections if you think the additional fuses are not needed.



My "Endurance" bus grew.  I will be flying IFR.  My Plan B for a main  

alternator failure is to have a sufficient secondary alternator to  

continue to power one Dynon Skyview screen, a Garmin 430W, audio panel  

and instrument lights and some indicators.  This could be 10A, peaking  

to 16A during transmissions.  Rather than a load meter, the low  

voltage indicator will confirm that the secondary alternator is  

carrying the load.  The dark and stormy night equipment is my Plan C.



Jeff Page

Dream Aircraft Tundra #10

fvalarm(at)rapidnet.net
Guest

Posted: Sun Nov 21, 2010 9:13 am Post subject: Z13/8 Rev Q comments

Jeff,



If I recall correctly and Bob may confirm, the SD8 aux alt actually puts out

up to 10mp at the rpm we fly.  Further, in a main alternator out scenario,

this is to be matched to the continuous draw of your minimum equipment list.

The surge current for transmitting etc can come from the battery.

Therefore, I would think that the SD8 will be sufficient as I'm doing

similar as you.  



Bevan

RV7A wiring, not flying yet.

  



--

Tundra10

Joined: 14 Jun 2010
Posts: 102
Location: Scarborough, Ontario

Posted: Mon Nov 22, 2010 5:35 am Post subject: Z13/8 Rev Q comments

 	  Quote: 	
		   Jeff,



 If I recall correctly and Bob may confirm, the SD8 aux alt actually puts out

 up to 10mp at the rpm we fly.  Further, in a main alternator out scenario,

 this is to be matched to the continuous draw of your minimum equipment list.

 The surge current for transmitting etc can come from the battery.

 Therefore, I would think that the SD8 will be sufficient as I'm doing

 similar as you.



 Bevan

 RV7A wiring, not flying yet.


	


I typically cruise at 2200 rpm.  For a Lycoming the pad ratio is  

1.3:1. at 2860 rpm, the SD-8 outputs approx 6.2A, which is just a  

little shy of what I need.  Some items, such as the instrument panel  

lights can be turned down or off.  The Skyview probably drawsa less  

current if it is dimmed as well.  The SD-8 will produce more power if  

I cruise at a higher rpm.  So my Plan B has me doing a little  

adjustment to keep the low voltage warning light off.



I would like to include a transponder on my endurance bus, but that  

would require the SD-20.  More cost and weight for a very unlikely  

situation.



Jeff Page

Dream Aircraft Tundra #10

fvalarm(at)rapidnet.net
Guest

Posted: Mon Nov 22, 2010 10:06 am Post subject: Z13/8 Rev Q comments

OK,



I stand corrected on the output of the SD-8.



Good info here.  I check my E-buss to see if it's less than 6 amp

continuous.



Bevan

RV7A wiring 



--

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Nov 22, 2010 1:46 pm Post subject: Z13/8 Rev Q comments

At 11:10 AM 11/21/2010, you wrote:

 	  Quote: 	
		  



Jeff,



If I recall correctly and Bob may confirm, the SD8 aux alt actually puts out

up to 10mp at the rpm we fly.


	


    Correct . . . sort of . . . the NORMAL manner in which

    alternators are rated calls for supporting the bus

    a the design set point. Say 14.2 - 14.6 volts. At the

    same time, a battery doesn't deliver significant energy

    into the system until the bus sags to 12.5 or so volts.



    The "normal" rating for the SD-8 is 8A.  However, the max load

    you can support with an SD-8 without taxing the battery

    closer to 10A because the bus voltage can be allowed to sag.

    This is why I don't show low-voltage warning on the E-bus.

    Even with an SD-8 powering it (as in Z-13/. A satisfactory

    operating design point voltage is probably below the trip

    point for a l3v warning light driver.



 	  Quote: 	
		  Further, in a main alternator out scenario,

this is to be matched to the continuous draw of your minimum equipment list.

The surge current for transmitting etc can come from the battery.

Therefore, I would think that the SD8 will be sufficient as I'm doing

similar as you.


	


    If we were comfortable with the idea of taxing

    a battery for a minimum endurance during alternator

    out operations, the act of adding an SD-8 on top

    of the battery does not convert the battery's stored

    energy into a sacred commodity.



    If you needed to support a 13A endurance bus under

    some conditions, why not? The points to be pondered

    are minute details for how "plan-b" or perhaps even

    a "plan-c" are implemented. What preventative

    maintenance tests to the battery will be religiously

    conducted to insure support for your "worst case"

    but planned-for scenario.



    Building an OBAM aircraft is a mixed bag. There's

    a LOT of planning supported by a lot of understanding

    that is NOT covered in a holy-watered POH for your

    project.



    You're on your own to make sure you've got "the plan" and

    understanding that meets your design goals. Well,

    not entirely on your own . . . there IS the AeroElectric

    List.



    This discussion highlights the importance of both

    load analysis and failure mode effects that drive

    configuration of both hardware and your "plan-b".

   Bob . . .

nuckolls.bob(at)aeroelect
Guest

Posted: Tue Nov 23, 2010 6:41 am Post subject: Z13/8 Rev Q comments

At 10:21 AM 11/21/2010, you wrote:



    (Me from earlier post) This illustrates the

    thinking behind the disparity between normal

    and alternate feed wire sizes.



Whether the feed is via the diode or the relay, the load is the same.

Shouldn't the wire capacity be the same ?



    Wire sizes may be based on a constellation of

    considerations. The legacy convention for 22 AWG

    on 5A breakers, 20AWG on 7A breakers, etc. is

    EXCEEDINGLY conservative and produces a system

    with low voltage drops and temperature rises.



    In this special case, we're considering the RARE

    but not-zero probability that the normal feed

    path wire could also be a fusible link. If we

    embrace the legacy policy of allowing wires of 6"

    or less to burn as along as they don't put other

    wires at risk, then the two short wires I've

    shown can be smaller because their voltage drops

    are short and their temperature rises very small.

    The smaller the wire, the faster they'll fuse.



My battery will be on the front of the firewall.  I planned the

connections between busses, contactors and relays all to be less than

6", so I originally omitted fuses.  I am minimizing my inventory by

purchasing only 14, 18 and 22 gauge wire, since the numbers worked out

that I would rarely need 16 and 20 gauge wire.  So the 16 awg feeders

changed to 14 awg.



    I can send you a chunk of any other size . . . but

    it would be better to go down as opposed to up

    in size for the un-fused, short wires. 20AWG would

    be fine. Use REAL PIDG terminals on these wires.



Since my busses will be fuse blocks, it is quite easy to use one of

the fuse positions to feed the bus.  However, I would prefer fewer

connections if you think the additional fuses are not needed.



    Okay, 20AWG and no fuses it is.



My "Endurance" bus grew.  I will be flying IFR.  My Plan B for a main

alternator failure is to have a sufficient secondary alternator to

continue to power one Dynon Skyview screen, a Garmin 430W, audio panel

and instrument lights and some indicators.  This could be 10A, peaking

to 16A during transmissions.  Rather than a load meter, the low

voltage indicator will confirm that the secondary alternator is

carrying the load.  The dark and stormy night equipment is my Plan C.



    Okay, does your SD-8 drive pad give you 4000 rpm

    at engine red-line? Even then, you won't keep a low

    voltage warning light OFF during endurance operations.

    The SD-8 may be too small for your plan-b loads in

    an un-limited endurance mode. You may have to up-size

    the alternator or plan for using significant battery

    energy to support the e-bus. This is STILL much better

    than a battery-only scenario but might call for a

    comfortable plan-b endurance of 1 hour or so. You'll

    want to measure your REAL plan-b loads as soon as

    all the goodies can be fired up.

   Bob . . .

longg(at)pjm.com
Guest

Posted: Tue Nov 23, 2010 7:50 am Post subject: Z13/8 Rev Q comments

IMO the SD-8 works well for the main power out scenario. I have the same

setup, but with a G530. One needs to ask oneself how many primary power

blackouts will ye observe on dark and stormy nights in flight.



Murphy says, there will be at least one. If you fly one every week, your

system has real issues and your preparedness is terrible. That would

also mean your planning is also terrible.



I find that with my Dynon pulling a whopping 1 amp, and my SL30 sending

a VOR signal to the Dynon HSI, I can handle most stormy night

situations. That may mean diversion, but you already have a problem, so

you're diverting anyway, right? If you fly all the way home with a major

problem at night, we'll you're just accepting lots of risk. All of these

designs are based on getting you to safety, not transcontinental flight

after major power loss.



Early system planning is fantastic, but I find most folks over do it.

What is your mission? Are you flying the mail every night? Based on the

traffic I see at most airports at night, I'm glad I don't depend on them

for food. I'd be starving.

Have a good handheld WAAS GPS on board and keep the batteries fresh. I

use the True Flight job which does approaches nearly as well as the

Garmin (in a pinch of course). Turn all the unnecessary crap off. That's

most of it.



Recently I bought one of those head mounted lamps. They are fantastic

for that situation. Get the best one you can buy. The one I bought has

the red night light included. I find I use it all the time now. 



Include some good cabin LED lights in your plan. Most cockpits are

poorly lighted for night operations. Get some good lighting that don't

draw much juice.



Most importantly have fun and good holiday.



Glenn 



--

nuckolls.bob(at)aeroelect
Guest

Posted: Tue Nov 23, 2010 9:42 am Post subject: Z13/8 Rev Q comments

<snip>

 	  Quote: 	
		  Include some good cabin LED lights in your plan. Most cockpits are

poorly lighted for night operations. Get some good lighting that don't

draw much juice.


	


  Most importantly have fun and good holiday.



    Well considered posting sir. Thank you. I'll remind the

    ol' timers and alert the newbies of the ideas

    and deliberations offered in the systems reliability

    chapter of the 'Connection.



    I've never owned and airplane with an electrical

    system in it . . . the one airplane I did own for

    a time wasn't a cross country machine (J-3).



    When I fly, it's always in a rented airplane selected

    from a fleet of perhaps a dozen options. I don't KNOW

    the history of the airplane's electrical system in

    detail. I PLAN to be able to complete a leg of my trip

    in the "J-3 mode". I.e., panel dark, master switch off.



http://aeroelectric.com/Pictures/Misc/Vacination_for_Dark_Panel_Syndrom.pdf



    So if your mission profiles call for system capabilities

    that cannot be COMFORTABLY conducted in a minimalist

    approach to backup, then as Glen suggests, think all

    this stuff through very carefully.



    It's not a task that should be scarry, just informative

    so that good judgement can prevail for any situation

    you're faced with. The vast majority of unhappy days

    in the cockpit or unplanned arrivals with the earth

    had nothing to do with an alternator failure or system

    configuration/maintenance. Poor judgement and/or over-

    stretched skills account for most of aviation's sad stories.



    Airplanes are never SAFE. Like cars, handguns,

    and skateboards, they are but tools that offer an

    opportunity for great utility, fun and personal

    satisfaction. Deliberations on the AeroElectric-

    List are not about safety. They're about risk

    reduction for how YOUR machine will be configured

    for how YOU plan to use it combined with YOUR

    skills to cope. This isn't something you get by

    reading the emergency procedures section of the

    POH.

   Bob . . .

Tundra10

Joined: 14 Jun 2010
Posts: 102
Location: Scarborough, Ontario

Posted: Wed Nov 24, 2010 7:14 am Post subject: Z13/8 Rev Q comments

> My battery will be on the front of the firewall.  I planned the

   > connections between busses, contactors and relays all to be less than

   > 6", so I originally omitted fuses.  I am minimizing my inventory by

   > purchasing only 14, 18 and 22 gauge wire, since the numbers worked out

   > that I would rarely need 16 and 20 gauge wire.  So the 16 awg feeders

   > changed to 14 awg.

   >

   >     I can send you a chunk of any other size . . . but

   >     it would be better to go down as opposed to up

   >     in size for the un-fused, short wires. 20AWG would

   >     be fine. Use REAL PIDG terminals on these wires.

   >

   > Since my busses will be fuse blocks, it is quite easy to use one of

   > the fuse positions to feed the bus.  However, I would prefer fewer

   > connections if you think the additional fuses are not needed.

   >

   >     Okay, 20AWG and no fuses it is.

So assuming all these wires are 6" or less, should I use 20awg and no  

fuses on both the diode and the relay path to the Endurance bus ?

   > My "Endurance" bus grew.  I will be flying IFR.  My Plan B for a main

   > alternator failure is to have a sufficient secondary alternator to

   > continue to power one Dynon Skyview screen, a Garmin 430W, audio panel

   > and instrument lights and some indicators.  This could be 10A, peaking

   > to 16A during transmissions.  Rather than a load meter, the low

   > voltage indicator will confirm that the secondary alternator is

   > carrying the load.  The dark and stormy night equipment is my Plan C.

   >

   >     Okay, does your SD-8 drive pad give you 4000 rpm

   >     at engine red-line? Even then, you won't keep a low

   >     voltage warning light OFF during endurance operations.

   >     The SD-8 may be too small for your plan-b loads in

   >     an un-limited endurance mode. You may have to up-size

   >     the alternator or plan for using significant battery

   >     energy to support the e-bus. This is STILL much better

   >     than a battery-only scenario but might call for a

   >     comfortable plan-b endurance of 1 hour or so. You'll

   >     want to measure your REAL plan-b loads as soon as

   >     all the goodies can be fired up.



For a while, I was planning on a larger secondary alternator, but the  

plan was getting out of control for an unlikely situation.  Glenn's  

comments make sense.  I think I am better off minimizing the  

electrical usage.  Some of the items, like the Skyview will probably  

take less in actual use than the rated maximum.



I can use a low voltage warning for the SD-8 with a lower voltage trip  

point, so I know when the battery is actually carrying part of the load.

At 2700 rpm, the SD-8 will be turning 3500 rpm, with higher fuel  

consumption.  I can make that tradeoff in flight, depending on the  

distance of the destination.



Jeff Page

Dream Aircraft Tundra #10

nuckolls.bob(at)aeroelect
Guest

Posted: Wed Nov 24, 2010 9:27 am Post subject: Z13/8 Rev Q comments

At 09:03 AM 11/24/2010, you wrote:

 	  Quote: 	
		  


	


For a while, I was planning on a larger secondary alternator, but the

plan was getting out of control for an unlikely situation.  Glenn's

comments make sense.  I think I am better off minimizing the

electrical usage.  Some of the items, like the Skyview will probably

take less in actual use than the rated maximum.



    Exactly! I can't tell you how many exercises in load

    analysis ended with considerable error in the final

    totals. Not so much from a variance in the published

    values for any one accessory . . . but when you have

    dozens of accessories . . .



    You know the ol' saw: "A million here, a billion there

    and pretty soon, we're talking about real money!"



    The neat thing about the e-bus architecture is the

    ease with which an experimental direct measurement

    of endurance loads can be accomplished. I've oft

    pondered the notion of adding a shunt in series

    with the e-bus alternate feed path. Silly of course,

    this is a one-time exercise that does not justify

    permanent installation of instrumentation.



I can use a low voltage warning for the SD-8 with a lower voltage trip

point, so I know when the battery is actually carrying part of the load.

At 2700 rpm, the SD-8 will be turning 3500 rpm, with higher fuel

consumption.  I can make that tradeoff in flight, depending on the

distance of the destination.



    Now you're THINKING about it. Today's bright stars

    for plan-b may differ from what you ultimately

    fly with. But every modification will go toward

    establishing and meeting design goals for NEVER

    experiencing an electrical emergency.



    Bob . . .

Tundra10

Joined: 14 Jun 2010
Posts: 102
Location: Scarborough, Ontario

Posted: Thu Nov 25, 2010 9:17 pm Post subject: Z13/8 Rev Q comments

 	  Quote: 	
		       Okay, 20AWG and no fuses it is.


	


So assuming all these wires are 6" or less, should I use 20awg and no

fuses on both the diode and the relay path to the Endurance bus ?



Jeff Page

Dream Aircraft Tundra #10

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Nov 26, 2010 6:52 am Post subject: Z13/8 Rev Q comments

At 11:07 PM 11/25/2010, you wrote:

 	  Quote: 	
		  



>     Okay, 20AWG and no fuses it is.



So assuming all these wires are 6" or less, should I use 20awg and no

fuses on both the diode and the relay path to the Endurance bus ?


	


     I WAS speaking of just the normal feed path through

     the diode . . . and it occurs to me that the "6-inch

     rule" would be speaking to TOTAL current pathway at

     risk . . . so strict observance of the rule would call

     for very short 20AWG conductors totalling 6" or less

     to wire the diode up between the main and e-bus.



     But then, that "rule" was never codified in any regulatory

     document I recall . . .  but that doesn't mean it didn't

     show up on some FAA offices "green sheets". My citation

     of that practices goes back a long way. I think I first

     recall discussing it at Cessna when somebody was contemplating

     the permanent wiring of a fat zener (50W stud mounted)

     to the main bus as a transient suppressor. This was

     before the zener market gave birth to the Transorb.



     Is the sum total of wire from battery bus to e-bus

     through the relay must surely be longer. Further, it's

     primary reason for existence is to power a bus from

     a battery not being charged by an alternator so we'll

     not want to squander energy in voltage drops. But it

     seems that the pathway would benefit from the conventional

     protection methods at BOTH ends since that wire can be

     SOURCED either from the main bus or the battery bus.



   Bob . . .

Tundra10

Joined: 14 Jun 2010
Posts: 102
Location: Scarborough, Ontario

Posted: Sat Nov 27, 2010 7:04 am Post subject: Z13/8 Rev Q comments

 	  Quote: 	
		  >>     Okay, 20AWG and no fuses it is.

>

> So assuming all these wires are 6" or less, should I use 20awg and no

> fuses on both the diode and the relay path to the Endurance bus ?



      I WAS speaking of just the normal feed path through

      the diode . . . and it occurs to me that the "6-inch

      rule" would be speaking to TOTAL current pathway at

      risk . . . so strict observance of the rule would call

      for very short 20AWG conductors totalling 6" or less

      to wire the diode up between the main and e-bus.



      But then, that "rule" was never codified in any regulatory

      document I recall . . .  but that doesn't mean it didn't

      show up on some FAA offices "green sheets". My citation

      of that practices goes back a long way. I think I first

      recall discussing it at Cessna when somebody was contemplating

      the permanent wiring of a fat zener (50W stud mounted)

      to the main bus as a transient suppressor. This was

      before the zener market gave birth to the Transorb.



      Is the sum total of wire from battery bus to e-bus

      through the relay must surely be longer. Further, it's

      primary reason for existence is to power a bus from

      a battery not being charged by an alternator so we'll

      not want to squander energy in voltage drops. But it

      seems that the pathway would benefit from the conventional

      protection methods at BOTH ends since that wire can be

      SOURCED either from the main bus or the battery bus.


	


OK.  It is easy to use fuses, since I can just use one of the  

positions of the fuse block on each end.



Jeff Page

Dream Aircraft Tundra #10

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