Today's Message Index:
----------------------
1. 05:40 AM - Re: AeroElectric-List Digest: 27 Msgs - 10/24/13 (Jay Bannister)
2. 06:32 AM - Re: Re: EXP 2 Bus workaround (Robert L. Nuckolls, III)
3. 07:03 AM - Electrically driven accidents (Robert L. Nuckolls, III)
4. 08:22 AM - Re: Re: AeroElectric-List Digest: 27 Msgs - 10/24/13 (Robert L. Nuckolls, III)
5. 08:48 AM - New Alternator, New Whine... (Matt Dralle)
6. 09:16 AM - Re: Electrically driven accidents (Jeff Luckey)
7. 10:17 AM - Re: New Alternator, New Whine... (David Lloyd)
8. 10:44 AM - Re: New Alternator, New Whine... (Dave Saylor)
9. 12:07 PM - Re: Electrically driven accidents (Robert L. Nuckolls, III)
10. 12:40 PM - Re: New Alternator, New Whine... (Robert L. Nuckolls, III)
11. 01:18 PM - Re: Electrically driven accidents (Peter Pengilly)
12. 01:31 PM - Re: Electrically driven accidents (Jeff Luckey)
13. 03:27 PM - Re: Electrically driven accidents (Robert L. Nuckolls, III)
14. 04:30 PM - Re: Alternator without a Battery (Thomas E Blejwas)
15. 05:36 PM - Re: EXP 2 Bus workaround (Fred Klein)
16. 07:43 PM - Re: EXP 2 Bus workaround (Robert L. Nuckolls, III)
17. 07:49 PM - Re: Alternator without a Battery (Robert L. Nuckolls, III)
18. 09:47 PM - Re: EXP 2 Bus workaround (John W Livingston)
19. 11:41 PM - Re: EXP 2 Bus workaround (Fred Klein)
20. 11:52 PM - Re: Re: EXP 2 Bus workaround (Fred Klein)
Message 1
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| Subject: | Re: AeroElectric-List Digest: 27 Msgs - 10/24/13 |
Does anyone know where I can get a schematic of the internal wiring of a TC
M Bendix mag/starter switch (BDX 10-357200-1) ?
Thanks - Jay Bannister
Message 2
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| Subject: | Re: EXP 2 Bus workaround |
Attached are the preliminary sketches for my current
thoughts on an architecture for single battery, single
alternator, electrically dependent engine. This line of
thinking is being developed as an preferred alternative
to Z-19.
This architecture has roots in Z-11 Three-Bus structure
with the addition of a Motive Power Bus (engine). With
the term E-bus already in legacy use, the MP-Bus terminology
offers a stand-out label that avoids confusion.
The major difference is the addition of the MP-bus having
normal feedpath from the main bus, alternate feedpath from
the battery . . . same as the E-Bus except BOTH pathways
have panel mounted switches. The e-bus is always hot any
time the main bus is hot, but the MP-Bus as power to the
engine needs to be controlled through both pathways.
I'm thinking that the EXP-bus can be folded into this
architecture by conversion of battery switch to DC master
and take alternator field through second pole. Convert
the 'avionice master' Engine A. Use switch between the
big red rockers as e-bus alternate feed. Switch to right
of Engine A is Engine B.
Old avionics bus becomes e-bus. Add fuse-block with
sufficient slots to accommodate MP-Bus loads.
Solid state relays in the alternate feed paths is
an option. Nothing wrong with the legacy automotive
plastic cube relays here but the DO draw about 100
mA each. Two relays in the battery only mode consumes
as much energy as another accessory . . . solid state
relays will consume a milliamp or so. That's a decision
that is not germane to current identification of loads
and shuffling them to the right bus.
Fred, if you would make a list of how the various
electrical loads would be distributed along these four
busses, I can move forward with a refinement of the
idea specific to your airplane. Don't worry about circuit
protection or wire sizing . . . just a list of everything
that gets a protected feeder and which bus you would
attach it to.
The next phase of the EXP-Bus workaround involves a
head-count of protected load-taps from existing e-bua
and main bus structures on the EXP-Bus assembly . . .
and distributing those load-taps amongst proposed
electro-whizzies. The MP-Bus is easy since it's an
external addition and not limited as to numbers of
load taps.
The relative risk factors for this architecture are
driven by the same factors that have been part-and-parcel
of owning and operating an airplane of any genre' whether
OBAM or TC.
KNOW YOUR BATTERY and it's EXPECTED DUTIES to meet
DESIGN GOALS for battery only operations. Then maintain
that capability as religiously as you change oil, tires
or use safety wire on prop bolts.
The two-battery band-aid is, perhaps, not as great
a risk mitigation as we once thought. This has been
a good exercise in the sifting of bits and pieces.
Critical review solicited and welcomed.
Bob . . .
Message 3
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| Subject: | Electrically driven accidents |
I have received the blessings of my client for conversion
of some aircraft accident investigation work-product into
teaching tools. Tools that illustrate the "Been there, done
that, let's don't do it again" sort of teaching.
I've cherry picked the items I produced and published
them in the N811HB directory on my website under
"Accidents."
http://tinyurl.com/ky7szec
The videos were crafted to give a gaggle of attorneys
some background of the technical issues with the idea
that material would be tailored and re-assembled
into work-product suited to show to a jury. The case
settled so the draft videos were never superceded.
Hence the mediocre production values.
There's a narrative of the accident as published by
the NTSB, a series of videos that explore a portion
of the electrical system dedicated to supplying
power to the ignition systems and one picture that
illustrates the manner in which a Dual-Feed, Ignition
Power Bus was implemented in this airplane.
Several of the videos speak to the value for
following instructions along with risk for failure to
reduce a system to the simplest, lowest common denominator
(FMEA).
Fred, your friend's observations on potential for
ADDED risk by stacking band-aid-on-top-of-band-aid
are germane to what happened on this airplane . . .
combined with poor craftsmanship and understanding
how the various components worked, individually or together.
If any List members become aware of an accident that involves
poor selection or application of electrical system
components, I'd be pleased to add them to this new
library on AeroElectric.com
Bob . . .
Message 4
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| Subject: | Re: AeroElectric-List Digest: 27 Msgs - 10/24/13 |
At 07:38 AM 10/25/2013, you wrote:
>Does anyone know where I can get a schematic of the internal wiring
>of a TCM Bendix mag/starter switch (BDX 10-357200-1) ?
>Thanks - Jay Bannister
>
Don't know about that particular product but if it's a
classic off-l-r-both-start switch, then it's 99% sure to
be set up like this
Emacs!
Bob . . .
Message 5
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| Subject: | New Alternator, New Whine... |
Dear Listers,
I just finished the Conditional Inspection on the RV-6. The day after I got everything
buttoned up and went out for a test flight, the alternator started to
flake. The old alternator was some no-name brand thing the original builder
got from somewhere. It never had enough output to power up everything during
taxi and landing. I suspect that it was probably a 40amp unit but there are no
markings on it so I don't know for sure. It had an external regulator; one
of those GM-style, two-wire gems.
So, I replaced it with a brand new PlanePower 60amp internally regulated and OVP'd
unit. The same one, in fact that I have on the RV-8. The good news is that
it really kicks butt and puts out plenty of power even at idle to keeps everything
powered up and the voltage level around 13v (max current draw is about
36amps, so the new alternator has plenty of headroom). With the lights off,
or at higher power settings it puts out a nice solid 14.1 volts or more. I'm
super happy.
Now the bad news. Now I have a loud alternator whine in the headphones! It's
particularly noticeable around 800-1100 RPM. The interesting thing about it is
that adjusting the volume of the Intercom, the Nav/Com, or the Stereo has no
impact of the volume of the whine. Only adjusting the two volumes (L+R) on the
Bose A20 headset dongle will change the volume level of the whine. That seems
like its the Bose that not liking the noise, but...? In the RV-8, I had the
exact same alternator, VP-200, Intercom, stereo, etc. with NO alternator whine.
However, I didn't buy the Bose A20 headsets until after I got the RV-6,
so I never used them in the RV-8. The RV-8 I had the previous model of headset,
the Bose X. I'm going to give the Bose X headphones a try in the RV-6 and
see if I hear the whine.
The A20's are much better headphones than the X's, so I really want to keep using
them, but that whine is pretty insidious. I worry that I may have the same
issue using the A20's in the RV-8 when I get it flying again.
I've been really careful, particularly in the RV-8, to run separate grounds to
everything and not use the airframe as a ground. In the RV-6, since it was already
built, I had less opportunity to do that. However, on the instrument panel,
since I rebuilt that from scratch, most everything electronic got its own
ground to the new grounding tree. Maybe I need to run a ground wire out to the
alternator?
Any insight you can lend would be most appreciated.
-
Matt Dralle
RV-8 #82880 N998RV "Ruby Vixen"
http://www.mattsrv8.com - Matt's Complete RV-8 Construction Log
http://www.mattsrv8.com/Mishap - Landing Mishap Rebuild Log
http://www.youtube.com/MattsRV8 - Matt's RV-8 HDTV YouTube Channel
Status: 172+ Hours TTSN - Rebuilding Fuselage After Landing Mishap...
RV-6 #20916 N360EM "The Flyer"
http://www.mattsrv6.com - Matt's RV-6 Revitalization Log
Status: 180+ Hours Since Purchase - Upgrades Complete; Now In Full Flyer Mode
Matt's Livermore Airport Live ATC Stream!
Check out the live ATC stream directly from my hangar at the Livermore
Airport. Includes both Tower and Ground transmissions. Archives too!
For entertainment purposes only. http://klvk.matronics.com
Message 6
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| Subject: | Re: Electrically driven accidents |
Hey Bob,=0A=0AWhen I try to view the 01 Fuse vs Breaker.wmv, my media playe
r, Windows Media Player in XP, the video plays for a couple of seconds then
stops & complains that the file is corrupt.- I've downloaded twice.- I
s anyone else having similar probs or is it my media player?=0A=0A-Jeff=0A
=0A=0A=0A=0A________________________________=0A From: "Robert L. Nuckolls,
III" <nuckolls.bob@aeroelectric.com>=0ATo: aeroelectric-list@matronics.com
=0ASent: Friday, October 25, 2013 7:03 AM=0ASubject: AeroElectric-List: Ele
ctrically driven accidents=0A =0A=0A--> AeroElectric-List message posted by
: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>=0A=0AI have rec
eived the blessings of my client for conversion=0Aof some- aircraft accid
ent investigation work-product into=0Ateaching tools. Tools that illustrate
the "Been there, done=0Athat, let's don't do it again" sort of teaching.
=0A=0AI've cherry picked the items I produced and published=0Athem in the N
811HB directory on my website under=0A"Accidents."=0A=0Ahttp://tinyurl.com/
ky7szec=0A=0AThe videos were crafted to give a gaggle of attorneys=0Asome b
ackground of the technical issues with the idea=0Athat material would be ta
ilored and re-assembled=0Ainto work-product suited to show to a jury. The c
ase=0Asettled so the draft videos were never superceded.=0AHence the medioc
re production values.=0A=0AThere's a narrative of the accident as published
by=0Athe NTSB, a series of videos that explore a portion=0Aof the electric
al system dedicated to supplying=0Apower to the ignition systems and one pi
cture that=0Aillustrates the manner in which a Dual-Feed, Ignition=0APower
Bus was implemented in this airplane.=0A=0ASeveral of the videos speak to t
he value for=0Afollowing instructions along with risk for failure to=0Aredu
ce a system to the simplest, lowest common denominator=0A(FMEA).=0A=0AFred,
your friend's observations on potential for=0AADDED risk by stacking band-
aid-on-top-of-band-aid=0Aare germane to what happened on this airplane . .
.=0Acombined with poor craftsmanship and understanding=0Ahow the various co
mponents worked, individually or together.=0A=0AIf any List members become
aware of an accident that involves=0Apoor selection or application of elect
rical system=0Acomponents, I'd be pleased to add them to this new=0Alibrary
===========
Message 7
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| Subject: | Re: New Alternator, New Whine... |
Matt,
Best guess is that the higher current alt. is insufficiently grounded and is
radiating via its current ground. For a test, I would fire up the RV to the
engine rpm that causes the worst phone noise and then, start shutting down
electrical loads reducing alt. current output. If the noise also
diminishes, then, I would install a better grd. buss to the alt.
Dave
_____________________________________________________________
----- Original Message -----
From: "Matt Dralle" <dralle@matronics.com>
Sent: Friday, October 25, 2013 8:47 AM
Subject: AeroElectric-List: New Alternator, New Whine...
> <dralle@matronics.com>
>
>
> Dear Listers,
>
> I just finished the Conditional Inspection on the RV-6. The day after I
> got everything buttoned up and went out for a test flight, the alternator
> started to flake. The old alternator was some no-name brand thing the
> original builder got from somewhere. It never had enough output to power
> up everything during taxi and landing. I suspect that it was probably a
> 40amp unit but there are no markings on it so I don't know for sure. It
> had an external regulator; one of those GM-style, two-wire gems.
>
> So, I replaced it with a brand new PlanePower 60amp internally regulated
> and OVP'd unit. The same one, in fact that I have on the RV-8. The good
> news is that it really kicks butt and puts out plenty of power even at
> idle to keeps everything powered up and the voltage level around 13v (max
> current draw is about 36amps, so the new alternator has plenty of
> headroom). With the lights off, or at higher power settings it puts out a
> nice solid 14.1 volts or more. I'm super happy.
>
> Now the bad news. Now I have a loud alternator whine in the headphones!
> It's particularly noticeable around 800-1100 RPM. The interesting thing
> about it is that adjusting the volume of the Intercom, the Nav/Com, or the
> Stereo has no impact of the volume of the whine. Only adjusting the two
> volumes (L+R) on the Bose A20 headset dongle will change the volume level
> of the whine. That seems like its the Bose that not liking the noise,
> but...? In the RV-8, I had the exact same alternator, VP-200, Intercom,
> stereo, etc. with NO alternator whine. However, I didn't buy the Bose A20
> headsets until after I got the RV-6, so I never used them in the RV-8.
> The RV-8 I had the previous model of headset, the Bose X. I'm going to
> give the Bose X headphones a try in the RV-6 and see if I hear the whine.
>
> The A20's are much better headphones than the X's, so I really want to
> keep using them, but that whine is pretty insidious. I worry that I may
> have the same issue using the A20's in the RV-8 when I get it flying
> again.
>
> I've been really careful, particularly in the RV-8, to run separate
> grounds to everything and not use the airframe as a ground. In the RV-6,
> since it was already built, I had less opportunity to do that. However,
> on the instrument panel, since I rebuilt that from scratch, most
> everything electronic got its own ground to the new grounding tree. Maybe
> I need to run a ground wire out to the alternator?
>
> Any insight you can lend would be most appreciated.
>
>
> -
> Matt Dralle
>
> RV-8 #82880 N998RV "Ruby Vixen"
> http://www.mattsrv8.com - Matt's Complete RV-8 Construction Log
> http://www.mattsrv8.com/Mishap - Landing Mishap Rebuild Log
> http://www.youtube.com/MattsRV8 - Matt's RV-8 HDTV YouTube Channel
> Status: 172+ Hours TTSN - Rebuilding Fuselage After Landing Mishap...
>
> RV-6 #20916 N360EM "The Flyer"
> http://www.mattsrv6.com - Matt's RV-6 Revitalization Log
> Status: 180+ Hours Since Purchase - Upgrades Complete; Now In Full Flyer
> Mode
>
> Matt's Livermore Airport Live ATC Stream!
> Check out the live ATC stream directly from my hangar at the Livermore
> Airport. Includes both Tower and Ground transmissions. Archives too!
> For entertainment purposes only. http://klvk.matronics.com
>
>
>
Message 8
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| Subject: | Re: New Alternator, New Whine... |
I've had a similar whine with a PP alternator and Zulu headsets. Same fix,
I slide the L&R volumes down to about mid and adjust everything else to
fit--the whine is much less. I've tried grounding the alternator case
without success. The whine gets louder with more output from the
alternator. I'm all ears, but the fact is I've learned to live with it.
Dave Saylor
831-750-0284 CL
On Fri, Oct 25, 2013 at 10:16 AM, David Lloyd <skywagon@charter.net> wrote:
> skywagon@charter.net>
>
> Matt,
> Best guess is that the higher current alt. is insufficiently grounded and
> is radiating via its current ground. For a test, I would fire up the RV to
> the engine rpm that causes the worst phone noise and then, start shutting
> down electrical loads reducing alt. current output. If the noise also
> diminishes, then, I would install a better grd. buss to the alt.
> Dave
>
> ______________________________**______________________________**_
>
> ----- Original Message ----- From: "Matt Dralle" <dralle@matronics.com>
> To: <aeroelectric-list@matronics.**com <aeroelectric-list@matronics.com>>
> Sent: Friday, October 25, 2013 8:47 AM
> Subject: AeroElectric-List: New Alternator, New Whine...
>
>
>> dralle@matronics.com>
>>
>>
>> Dear Listers,
>>
>> I just finished the Conditional Inspection on the RV-6. The day after I
>> got everything buttoned up and went out for a test flight, the alternator
>> started to flake. The old alternator was some no-name brand thing the
>> original builder got from somewhere. It never had enough output to power
>> up everything during taxi and landing. I suspect that it was probably a
>> 40amp unit but there are no markings on it so I don't know for sure. It
>> had an external regulator; one of those GM-style, two-wire gems.
>>
>> So, I replaced it with a brand new PlanePower 60amp internally regulated
>> and OVP'd unit. The same one, in fact that I have on the RV-8. The good
>> news is that it really kicks butt and puts out plenty of power even at idle
>> to keeps everything powered up and the voltage level around 13v (max
>> current draw is about 36amps, so the new alternator has plenty of
>> headroom). With the lights off, or at higher power settings it puts out a
>> nice solid 14.1 volts or more. I'm super happy.
>>
>> Now the bad news. Now I have a loud alternator whine in the headphones!
>> It's particularly noticeable around 800-1100 RPM. The interesting thing
>> about it is that adjusting the volume of the Intercom, the Nav/Com, or the
>> Stereo has no impact of the volume of the whine. Only adjusting the two
>> volumes (L+R) on the Bose A20 headset dongle will change the volume level
>> of the whine. That seems like its the Bose that not liking the noise,
>> but...? In the RV-8, I had the exact same alternator, VP-200, Intercom,
>> stereo, etc. with NO alternator whine. However, I didn't buy the Bose A20
>> headsets until after I got the RV-6, so I never used them in the RV-8. The
>> RV-8 I had the previous model of headset, the Bose X. I'm going to give
>> the Bose X headphones a try in the RV-6 and see if I hear the whine.
>>
>> The A20's are much better headphones than the X's, so I really want to
>> keep using them, but that whine is pretty insidious. I worry that I may
>> have the same issue using the A20's in the RV-8 when I get it flying again.
>>
>> I've been really careful, particularly in the RV-8, to run separate
>> grounds to everything and not use the airframe as a ground. In the RV-6,
>> since it was already built, I had less opportunity to do that. However, on
>> the instrument panel, since I rebuilt that from scratch, most everything
>> electronic got its own ground to the new grounding tree. Maybe I need to
>> run a ground wire out to the alternator?
>>
>> Any insight you can lend would be most appreciated.
>>
>>
>> -
>> Matt Dralle
>>
>> RV-8 #82880 N998RV "Ruby Vixen"
>> http://www.mattsrv8.com - Matt's Complete RV-8 Construction Log
>> http://www.mattsrv8.com/Mishap - Landing Mishap Rebuild Log
>> http://www.youtube.com/**MattsRV8 <http://www.youtube.com/MattsRV8> -
>> Matt's RV-8 HDTV YouTube Channel
>> Status: 172+ Hours TTSN - Rebuilding Fuselage After Landing Mishap...
>>
>> RV-6 #20916 N360EM "The Flyer"
>> http://www.mattsrv6.com - Matt's RV-6 Revitalization Log
>> Status: 180+ Hours Since Purchase - Upgrades Complete; Now In Full Flyer
>> Mode
>>
>> Matt's Livermore Airport Live ATC Stream!
>> Check out the live ATC stream directly from my hangar at the Livermore
>> Airport. Includes both Tower and Ground transmissions. Archives too!
>> For entertainment purposes only. http://klvk.matronics.com
>>
>>
>>
>>
>>
>>
>>
>
>
Message 9
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| Subject: | Re: Electrically driven accidents |
At 11:14 AM 10/25/2013, you wrote:
Hey Bob,
When I try to view the 01 Fuse vs Breaker.wmv, my media player,
Windows Media Player in XP, the video plays for a couple of seconds
then stops & complains that the file is corrupt. I've downloaded
twice. Is anyone else having similar probs or is it my media player?
I am mystified. The ByteCount for file on the website
and my desktop are the same but when I downloaded from
the website, the captured file was shorter.
The source file plays fine . . . I reloaded it to
the site and downloaded for a check-run. Seems
to be okay now.
Bob . . .
Message 10
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| Subject: | Re: New Alternator, New Whine... |
Now the bad news. Now I have a loud alternator
whine in the headphones! It's particularly
noticeable around 800-1100 RPM. The interesting
thing about it is that adjusting the volume of
the Intercom, the Nav/Com, or the Stereo has no
impact of the volume of the whine. Only
adjusting the two volumes (L+R) on the Bose A20
headset dongle will change the volume level of
the whine. That seems like its the Bose that
not liking the noise, but...? In the RV-8, I
had the exact same alternator, VP-200, Intercom,
stereo, etc. with NO alternator whine. However,
I didn't buy the Bose A20 headsets until after I
got the RV-6, so I never used them in the RV-8.
The RV-8 I had the previous model of headset, the
Bose X. I'm going to give the Bose X headphones
a try in the RV-6 and see if I hear the whine.
These symptoms scream (or should I say whine?) GROUND LOOP!
I've been really careful, particularly in the
RV-8, to run separate grounds to everything and
not use the airframe as a ground. In the RV-6,
since it was already built, I had less
opportunity to do that. However, on the
instrument panel, since I rebuilt that from
scratch, most everything electronic got its own
ground to the new grounding tree. Maybe I need
to run a ground wire out to the alternator?
I'd check to see that ALL grounds to the Bose system,
audio AND power(-) are grounded at the same place
power(-) and audio for the intercom are grounded.
Your 60A alternator isn't bad and probably isn't
installed wrong . . . it's just capable of putting
more noise into the loop that existed before the
alternator was replaced.
The single point ground concept is often mis-understood
to mean signal grounds only. Given that many if not most
pieces of avionics have an internal common chassis ground
for both signal and ground, you need to treat power grounds
the same as signal grounds.
Do you have a dedicated black-box ground on the
instrument panel or does everything go to a firewall
block? If so, your two points of ground on the airframe
are chassis grounds on the panel and wired grounds
on the firewall.
Bob . . .
Message 11
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| Subject: | Re: Electrically driven accidents |
Try vlc media player?
http://www.videolan.org/vlc/index.html
On Oct 25, 2013 8:23 PM, "Robert L. Nuckolls, III" <
nuckolls.bob@aeroelectric.com> wrote:
> nuckolls.bob@aeroelectric.com**>
>
>
> At 11:14 AM 10/25/2013, you wrote:
> Hey Bob,
>
> When I try to view the 01 Fuse vs Breaker.wmv, my media player, Windows
> Media Player in XP, the video plays for a couple of seconds then stops &
> complains that the file is corrupt. I've downloaded twice. Is anyone else
> having similar probs or is it my media player?
>
> I am mystified. The ByteCount for file on the website
> and my desktop are the same but when I downloaded from
> the website, the captured file was shorter.
>
> The source file plays fine . . . I reloaded it to
> the site and downloaded for a check-run. Seems
> to be okay now.
>
>
> Bob . . .
>
>
Message 12
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| Subject: | Re: Electrically driven accidents |
Got it.- =0A=0A=0A2 data points:=0A1. the original file you had up earlie
r today was about 64 MB.- This new one is about 49 MB.=0A2. the download
a few minutes ago (1315 PDT) took much longer than the download this mornin
g. This AM it took <5 min, this PM took > 30 min.- Probably a server load
issue - just though I'd mention it.=0A=0A=0AThx for fixing quickly,=0A=0A-
Jeff=0A=0A=0A=0A=0A________________________________=0A From: "Robert L. Nuc
kolls, III" <nuckolls.bob@aeroelectric.com>=0ATo: aeroelectric-list@matroni
cs.com =0ASent: Friday, October 25, 2013 12:06 PM=0ASubject: Re: AeroElectr
ic-List: Electrically driven accidents=0A =0A=0A--> AeroElectric-List messa
ge posted by: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>=0A
=0A=0AAt 11:14 AM 10/25/2013, you wrote:=0AHey Bob,=0A=0AWhen I try to view
the 01 Fuse vs Breaker.wmv, my media player, Windows Media Player in XP, t
he video plays for a couple of seconds then stops & complains that the file
is corrupt.- I've downloaded twice.- Is anyone else having similar pro
bs or is it my media player?=0A=0A- I am mystified. The ByteCount for fil
e on the website=0A- and my desktop are the same but when I downloaded fr
om=0A- the website, the captured file was shorter.=0A=0A- The source fi
le plays fine . . . I reloaded it to=0A- the site and downloaded for a ch
=================
Message 13
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| Subject: | Re: Electrically driven accidents |
At 03:30 PM 10/25/2013, you wrote:
>Got it.
>
>2 data points:
>1. the original file you had up earlier today was about 64 MB. This
>new one is about 49 MB.
>2. the download a few minutes ago (1315 PDT) took much longer than
>the download this morning. This AM it took <5 min, this PM took > 30
>min. Probably a server load issue - just though I'd mention it.
>
>Thx for fixing quickly,
The second upload had been processed for lower
bitrate to make it load better. Thanks for the
feedback!
Bob . . .
Message 14
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| Subject: | Re: Alternator without a Battery |
Yes, I accept the mission - I'm responsible for the safety of my aircraft and I
see potential benefits in having the ability to disconnect the batteries. Unfortunately,
my last formal education in electronics was a freshman physics class
many, many years ago. To fill some of the void, I read the AeroElectric Connection,
but sometimes struggle with cognition and retention. I'm counting
on Bob and others on the list for critical evaluation.
I see risks in 3 areas: physical risk associated with the actual operation of
the alternator without a battery, i.e., damage to the alternator itself or other
components; risks associated with circuitry changes to allow for operation
without a battery; and risks in operational changes, i.e., people engineering
or cockpit management. I'll leave the first of these to last, because I feel
least confident with my understanding.
Since the batteries (I'm planning on 2 in my system) are no longer "always on,"
they are logically each connected through a contactor or other type of switch.
I won't rehash the recent discussions of contactors, but with two batteries
and contactors, the risk of contactor failure is small compared to the additional
redundancy (assuming operational recognition and response) of an alternator
without a battery. For my system, the steady-state load will be on the order
of 15 amps, which shouldn't overly challenge a traditional style contactor,
e.g., from B&C. Although I need to design and evaluate the entire electrical
system, I don't see any other inherent circuitry changes. My basic approach
is a ocircuit to which the batteries and alternator may or may not be connected.
The buses may be physically connected to the circuit near a particular power
source, but the primary purpose of multiple buses is to allow critical redundant
devices (primarily fuel pumps and ECUs) to be connected in such a way that
the loss of a single connection will not cause loss of power or, at worst,
can be recovered by one or two switches.
With the potential for one battery to be disconnected in "normal flight," operations
need to be established to ensure both batteries are charged and available.
This could be as simple as connecting both into the charging circuit, but
then power is being drawn from both and neither is a traditional "backup." My
preference is for one to be connected for one leg of a trip and the other for
the return or next leg. This works particularly well if I choose to use lithium
phosphate batteries, because their unused discharge rate is extremely low.
(I'm periodically checking online for fires with Shorai batteries, because these
are widely used on motorcycles. So far, mishaps are few and not explosive.
Also, one of the areas under my purview in a past position was a battery destructive-test
lab. I'll be trying to get non-proprietary info from the people
at this lab.) I also think it is prudent to monitor each battery during flight
with instruments like the MGL BAT-1, which provide both voltage and current.
If the engine stops in flight, I don't want to have to remember how the electrical
system works to recover. If no electrical power, check the battery monitors
and change contactors to the unused one. If there is electrical power, switch
fuel pumps and switch ECU power source (both changing to a different bus and
associated connections) and finally switch to backup ECU. For me this is simpler
than determining what to switch at the top of Z-19, but that probably just
shows my lack of familiarity with aero-electrical speak. I don't see using
the alternator without a battery except for the following. Monitoring of the
batteries shows a problem with a battery and the other one replaces it. (Or
maybe it is the standby battery with a problem.) Before being able to land,
the second battery starts acting up. Now, switch both off and do a precautionary
landing ASAP.
Now, what about the risks to the alternator or other critical devices because an
alternator is running without a connected battery? First, Viking has claimed
that the alternator can be so run. A capacitor was initially required, which
makes sense in that it would "smooth" the output; but, curiously, engine owners
were later instructed to remove the capacitor. I could find no explanation
for the change and my memory is that an inquiry was ignored. I'll make my
own attempt at finding out why. At this point, I plan to design with the option
and test the output after completion. I can see no harm in having a capacitor
in the circuit, but hopefully others will correct me if I'm wrong.
Sorry if I've missed the point of your suggestion or gone off on too many tangents.
I realize that a schematic would have been helpful for this discussion,
but I'm just starting to teach myself TurboCAD and who knows how long that will
take.
Tom
Sent from my iPad
Message 15
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| Subject: | Re: EXP 2 Bus workaround |
Bob, thank you for your analysis and recommendations...they greatly enhance my
learning experience here...please see my indents below...I have additional comments
(later) on your posted circuit diagram of this morning...Fred
On Oct 23, 2013, at 4:41 PM, Robert L. Nuckolls, III wrote:
> Okay, getting closer.
>
> (1) Recommend you take the engine bus normal feedpath directly
> from the main bus through the diode. A normal Engine ON/OFF
> switch in this path seems to make sense see (6).
I don't understand how I might "take the engine bus normal feedpath directly
from the main bus through the diode." It seems to imply to me that I poke around
on the circuit board and find a place to attach a wire. I thought my proposal
to tap the existing two 11 amp AUX circuits with a fast-on spade or two would
be a rather elegant way to use what's available. (See my comments on your item
(6) below.)
> (2) add 30A maxi fuse in series with Engine Bus Alternate
> Feed path and being engine power forward on 10AWG wire.
OK...straightforward enough...
>
> (3) Take E-Bus alternate feed directly from the battery on
> it's own 7A fuse and 14AWG wire . . . 10A fuse if determined
> necessary later.
I can do that; this adds another wire forward from rear battery to bus...What's
the advantage of doing this rather than using a short wire to the Engine (MP)
bus, as long as the total E-bus + MP bus loads can be handled by the EXP Bus
circuit from which power is being drawn? Normally (I believe the) E-bus alternate
feed will ONLY be activated in conjunction w/ the Engine (MP) bus alternate
feed (sized accordingly) is activated.
> (4) Go to solid state relays for e-bus and E-bus alternate
> feeds, either Eric's or ours.
OK
> (5) Run #2 fuel pump from main bus through polyfuse and
> EXP Bus switch.
Let's talk about the 2 fuel pumps for a MPEFI engine. Unlike w/ carb engines,
the 2nd pump is not used as a boost pump. I'm advised that w/ a MPEFI engine,
one never wants to run more than ONE pump at a time due to excessive pressure
in the system.
This is why I've been showing 2 switches in series...the first switch powers
up a single fuel pump...whether that is pump #1 or pump #2 depends on the second
switch. The reason for two fuel pumps is to ensure fuel flow in the event of
either a pump failure or a clogged filter. These events can occur regardless
of where the elec power is coming from. I say it's essential that BOTH pumps
can be energized either thru the EXP Bus or the Engine (MP) bus alternate feed.
I believe your point (5) misconstrues the purpose of dual pumps in a MPEFI engine.
What am I missing?
> (6) I see no value in having separate switches for
> injectors, coils, normal pump or ECU feed. One switch
> in normal feed path for normal engine ops, one switch
> to control alternate feed path. When and why would you
> ever operate one of these switches independently of
> the others. Two ways to power engine . . . normal and
> alternate.
On reflection, I understand (finally)...a single switch it is.
>
> (7) Suggest separate fuses for each injector and coil
> assuming engine produces some useable power with any
> one fuse open.
This sounds like a novel idea...I'm wondering if anyone's ever done this before?..
how much increased complexity is entailed?...and whether or not historical
rates of injector and coil failures suggest that this would be prudent?
> (8) Starter can control from main bus.
True...and...w/ my particular combination of engine, reduction ratio, propeller,
and aircraft performance envelope, although I THINK that with engine out,
prop would windmill sufficient to restart engine, if Master switch was OFF, I'd
like to be able to spin the starter...that was the INTENT of what the diagram
shows...What do you think?...I'm unsure as to whether or not the wiring diagram
allows for that to happen.
> (9) Turn existing avionics bus into e-bus, convert
> old avionics master into alternate feed path control
> switch. Normal feed path comes from main bus through
> diode.
I'm completely in the dark as to my understanding of what physical changes must
be made to the EXP Bus to accomplish this.
>
> (10) You speak to "room for breakers/fuses on panel"
> suggest these be out of sight, of reach.
That would be possible of course, though if CBs are used, questionable. I'm presuming
that you want them out of sight to reduce workload in an emergency, and
to avoid possibly exacerbating conditions by resetting popped CBs...is that
so?
>
>
>
>
> Bob . . .
>
>
>
Message 16
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| Subject: | Re: EXP 2 Bus workaround |
At 07:35 PM 10/25/2013, you wrote:
>
>Bob, thank you for your analysis and recommendations...they greatly
>enhance my learning experience here...please see my indents
>below...I have additional comments (later) on your posted circuit
>diagram of this morning...Fred
We're getting the cart out in front. Let's get a 98%
golden list of electro-whizzies and where they'll
get powered.
The Z-08 drawing is just architecture for now, the mechanism
by which an EXP-Bus duplicates or emulates the philosophy
is a separate task.
> >
> > (3) Take E-Bus alternate feed directly from the battery on
> > it's own 7A fuse and 14AWG wire . . . 10A fuse if determined
> > necessary later.
>
> I can do that; this adds another wire forward from
> rear battery to bus...What's the advantage of doing this rather
> than using a short wire to the Engine (MP) bus, as long as the
> total E-bus + MP bus loads can be handled by the EXP Bus circuit
> from which power is being drawn? Normally (I believe the) E-bus
> alternate feed will ONLY be activated in conjunction w/ the Engine
> (MP) bus alternate feed (sized accordingly) is activated.
We can thrash this detail later . . .
> Let's talk about the 2 fuel pumps for a MPEFI
> engine. Unlike w/ carb engines, the 2nd pump is not used as a boost
> pump. I'm advised that w/ a MPEFI engine, one never wants to run
> more than ONE pump at a time due to excessive pressure in the system.
How does this happen? I understand that there's a pressure
regulator downstream of the pump outputs. Paralleling two
active pumps only increases potential for flow . . . like
hooking two batteries in parallel.
> > (7) Suggest separate fuses for each injector and coil
> > assuming engine produces some useable power with any
> > one fuse open.
>
> This sounds like a novel idea...I'm wondering
> if anyone's ever done this before?.. how much increased complexity
> is entailed?...and whether or not historical rates of injector and
> coil failures suggest that this would be prudent?
I've seen this before. The idea is that no single failure
takes out all injectors and an engine will produce useful
power with one injector down.
> > (8) Starter can control from main bus.
>
> True...and...w/ my particular combination of
> engine, reduction ratio, propeller, and aircraft performance
> envelope, although I THINK that with engine out, prop would
> windmill sufficient to restart engine, if Master switch was OFF,
> I'd like to be able to spin the starter...that was the INTENT of
> what the diagram shows...What do you think?...I'm unsure as to
> whether or not the wiring diagram allows for that to happen.
Is anyone flying this combination of hardware? How much does
IAS need to be reduced to stop a windmilling prop? The few
times I stopped the prop on a TC airplane I had to really
work at it. The idea that one needs access to a starter
motor in flight is mostly without foundation. This is a
fact you need to resolve for your harware combination.
> > (9) Turn existing avionics bus into e-bus, convert
> > old avionics master into alternate feed path control
> > switch. Normal feed path comes from main bus through
> > diode.
>
> I'm completely in the dark as to my understanding
> of what physical changes must be made to the EXP Bus to accomplish this.
Later . . . I don't think it's going to be difficult.
> >
> > (10) You speak to "room for breakers/fuses on panel"
> > suggest these be out of sight, of reach.
>
> That would be possible of course, though if CBs are
> used, questionable. I'm presuming that you want them out of sight
> to reduce workload in an emergency, and to avoid possibly
> exacerbating conditions by resetting popped CBs...is that so?
The only time a fuse or breaker opens is because something
is broke (which means new fuse doesn't help) or the circuit
protection is undersized (nuisance trip - which on an OBAM
aircraft gets fixed). Hence, no value for being able to see/reach
breakers and fuses.
Bob . . .
Message 17
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| Subject: | Re: Alternator without a Battery |
At 06:29 PM 10/25/2013, you wrote:
><tomblejwas@yahoo.com>
>
>Yes, I accept the mission - I'm responsible for the safety of my
>aircraft and I see potential benefits in having the ability to
>disconnect the batteries. Unfortunately, my last formal education
>in electronics was a freshman physics class many, many years
>ago. To fill some of the void, I read the AeroElectric Connection,
>but sometimes struggle with cognition and retention. I'm counting
>on Bob and others on the list for critical evaluation.
The only time I think one deliberately shuts off batteries
in flight is for smoke in the cockpit . . . which means
alternator needs to be off too.
>I see risks in 3 areas: physical risk associated with the actual
>operation of the alternator without a battery, i.e., damage to the
>alternator itself or other components; risks associated with
>circuitry changes to allow for operation without a battery; and
>risks in operational changes, i.e., people engineering or cockpit
>management. I'll leave the first of these to last, because I feel
>least confident with my understanding.
Many alternators run fine without a battery. They may
not start but once in operation, they produce useful energy
with a disconnected battery. Bonanzas and Barons have offered
this feature for decades.
>Since the batteries (I'm planning on 2 in my system) are no longer
>"always on," they are logically each connected through a contactor
>or other type of switch.
Why two batteries?
> I won't rehash the recent discussions of contactors, but with two
> batteries and contactors, the risk of contactor failure is small
> compared to the additional redundancy (assuming operational
> recognition and response) of an alternator without a battery. For
> my system, the steady-state load will be on the order of 15 amps,
> which shouldn't overly challenge a traditional style contactor,
> e.g., from B&C. Although I need to design and evaluate the entire
> electrical system, I don't see any other inherent circuitry
> changes. My basic approach is a ocircuit to which the batteries
> and alternator may or may not be connected. The buses may be
> physically connected to the circuit near a particular power source,
> but the primary purpose of multiple buses is to allow critical
> redundant devices (primarily fuel pumps and ECUs) to be connected
> in such a way that the loss of a single connection will not cause
> loss of power or, at worst, can be recovered by one or two switches.
Have you been following the thread on Fred's project?
Check the drawings I published earlier today and assess
potential for missing your design goals. The question is,
suppose a contactor DOES fail, how does that impact risks
for comfortable termination of flight?
Bob . . .
Message 18
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| Subject: | Re: EXP 2 Bus workaround |
I am still stumped as to why you would recommend one battery. I could
agree if the one alternator is guaranteed to work without the battery in
the circuit, but not without that backup. You must think batteries are
much more reliable than I do.
John
On 10/25/2013 10:42 PM, Robert L. Nuckolls, III wrote:
> At 07:35 PM 10/25/2013, you wrote:
>> <fklein@orcasonline.com>
>>
>> Bob, thank you for your analysis and recommendations...they greatly
>> enhance my learning experience here...please see my indents below...I
>> have additional comments (later) on your posted circuit diagram of
>> this morning...Fred
>
> * We're getting the cart out in front. Let's get a 98%
> golden list of electro-whizzies and where they'll
> get powered.
>
> The Z-08 drawing is just architecture for now, the mechanism
> by which an EXP-Bus duplicates or emulates the philosophy
> is a separate task.
>
> *
>> >
>> > (3) Take E-Bus alternate feed directly from the battery on
>> > it's own 7A fuse and 14AWG wire . . . 10A fuse if determined
>> > necessary later.
>>
>> I can do that; this adds another wire forward from rear battery to
>> bus...What's the advantage of doing this rather than using a short
>> wire to the Engine (MP) bus, as long as the total E-bus + MP bus
>> loads can be handled by the EXP Bus circuit from which power is being
>> drawn? Normally (I believe the) E-bus alternate feed will ONLY be
>> activated in conjunction w/ the Engine (MP) bus alternate feed (sized
>> accordingly) is activated.
>
> * We can thrash this detail later . . .
>
>
> *
>> Let's talk about the 2 fuel pumps for a MPEFI engine. Unlike w/ carb
>> engines, the 2nd pump is not used as a boost pump. I'm advised that
>> w/ a MPEFI engine, one never wants to run more than ONE pump at a
>> time due to excessive pressure in the system.
>
> * How does this happen? I understand that there's a pressure
> regulator downstream of the pump outputs. Paralleling two
> active pumps only increases potential for flow . . . like
> hooking two batteries in parallel.
>
> *
>> > (7) Suggest separate fuses for each injector and coil
>> > assuming engine produces some useable power with any
>> > one fuse open.
>>
>> This sounds like a novel idea...I'm wondering if anyone's ever done
>> this before?.. how much increased complexity is entailed?...and
>> whether or not historical rates of injector and coil failures suggest
>> that this would be prudent?
>
> * I've seen this before. The idea is that no single failure
> takes out all injectors and an engine will produce useful
> power with one injector down.
>
>
> *
>> > (8) Starter can control from main bus.
>>
>> True...and...w/ my particular combination of engine, reduction ratio,
>> propeller, and aircraft performance envelope, although I THINK that
>> with engine out, prop would windmill sufficient to restart engine, if
>> Master switch was OFF, I'd like to be able to spin the starter...that
>> was the INTENT of what the diagram shows...What do you think?...I'm
>> unsure as to whether or not the wiring diagram allows for that to happen.
>
> * Is anyone flying this combination of hardware? How much does
> IAS need to be reduced to stop a windmilling prop? The few
> times I stopped the prop on a TC airplane I had to really
> work at it. The idea that one needs access to a starter
> motor in flight is mostly without foundation. This is a
> fact you need to resolve for your harware combination.
>
>
> *
>> > (9) Turn existing avionics bus into e-bus, convert
>> > old avionics master into alternate feed path control
>> > switch. Normal feed path comes from main bus through
>> > diode.
>>
>> I'm completely in the dark as to my understanding of what physical
>> changes must be made to the EXP Bus to accomplish this.
>
> * Later . . . I don't think it's going to be difficult.
>
> *
>> >
>> > (10) You speak to "room for breakers/fuses on panel"
>> > suggest these be out of sight, of reach.
>>
>> That would be possible of course, though if CBs are used,
>> questionable. I'm presuming that you want them out of sight to reduce
>> workload in an emergency, and to avoid possibly exacerbating
>> conditions by resetting popped CBs...is that so?
>
> * The only time a fuse or breaker opens is because something
> is broke (which means new fuse doesn't help) or the circuit
> protection is undersized (nuisance trip - which on an OBAM
> aircraft gets fixed). Hence, no value for being able to see/reach
> breakers and fuses.
>
>
> *
>
> Bob . . .
>
> *
>
>
> *
Message 19
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| Subject: | Re: EXP 2 Bus workaround |
On Oct 25, 2013, at 7:42 PM, Robert L. Nuckolls, III wrote:
>> Let's talk about the 2 fuel pumps for a MPEFI
engine. Unlike w/ carb engines, the 2nd pump is not used as a boost
pump. I'm advised that w/ a MPEFI engine, one never wants to run more
than ONE pump at a time due to excessive pressure in the system.
>
> How does this happen? I understand that there's a pressure
> regulator downstream of the pump outputs. Paralleling two
> active pumps only increases potential for flow . . . like
> hooking two batteries in parallel.
Bob...I get your point about pressure...let me try to
get better info...it may be that restriction due to size of return fuel
line can't accept the increased flow...I'll check back about this.
>> > (8) Starter can control from main bus.
>>
>> True...and...w/ my particular combination of engine,
reduction ratio, propeller, and aircraft performance envelope, although
I THINK that with engine out, prop would windmill sufficient to restart
engine, if Master switch was OFF, I'd like to be able to spin the
starter...that was the INTENT of what the diagram shows...What do you
think?...I'm unsure as to whether or not the wiring diagram allows for
that to happen.
>
> Is anyone flying this combination of hardware? How much does
> IAS need to be reduced to stop a windmilling prop? The few
> times I stopped the prop on a TC airplane I had to really
> work at it. The idea that one needs access to a starter
> motor in flight is mostly without foundation. This is a
> fact you need to resolve for your harware combination.
Bob...I'm getting some data on this.
Fred
Message 20
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| Subject: | Re: EXP 2 Bus workaround |
On Oct 25, 2013, at 6:32 AM, Robert L. Nuckolls, III wrote:
> Attached are the preliminary sketches for my current
> thoughts on an architecture for single battery, single
> alternator, electrically dependent engine. This line of
> thinking is being developed as an preferred alternative
> to Z-19.
Bob...I'm delighted that my queries have triggered your
taking a fresh look at Z-19...and presumably, Z-19RB.
>
> This architecture has roots in Z-11 Three-Bus structure
> with the addition of a Motive Power Bus (engine). With
> the term E-bus already in legacy use, the MP-Bus terminology
> offers a stand-out label that avoids confusion.
...perhaps it won't be too long before MP busses will
morph into ones intended for truly all electric power trains...
>
> The major difference is the addition of the MP-bus having
> normal feedpath from the main bus, alternate feedpath from
> the battery . . . same as the E-Bus except BOTH pathways
> have panel mounted switches. The e-bus is always hot any
> time the main bus is hot, but the MP-Bus as power to the
> engine needs to be controlled through both pathways.
>
> I'm thinking that the EXP-bus can be folded into this
> architecture by conversion of battery switch to DC master
> and take alternator field through second pole. Convert
> the 'avionice master' Engine A. Use switch between the
> big red rockers as e-bus alternate feed. Switch to right
> of Engine A is Engine B.
=46rom the get-go, my intent has been to supplement the
capabilities of the EXP Bus to provide for the special requirements for
a MPEFI engine AND to provide the alternate feeds featured in
AeroElectric's Z-xx diagrams in case something goes amiss.
I question your suggestion to:
> Use switch between the big red rockers as e-bus alternate feed. Switch
to right of Engine A is Engine B.
I'm reluctant to interpose within the row of EXP Bus
rockers, switches which would only be used during an emergency.
Conceptually, I much prefer the notion of having a row
of rockers, all of which are used in the course of normal
operations...and a second, distinctly different row of rockers which
will only be used during emergencies.
(The wide, red, Master switch at the left
end...distinctive in both width and color...is of course used both in
normal and emergency ops.)
Organizing the panel in this manner...at least to
me...sets the stage for calm and cool actions when under stress.
I understand your desire for me to proceed w/ listing of
elec loads for all components...a task I recognise as essential...but
first I want to be confident that I understand the big picture. And the
big picture for me is how we supplement the capabilities of the EXP Bus
in order to have the benefits of engine and endurance busses with
alternate feeds from the battery.
Notwithstanding the shortcomings, some poor choices, and
undoubtedly some serious errors, the last diagram I posted (Revision
#XX) did two things of note:
First, it pulls power from the EXP Master Bus for the MP
(engine) bus from 2 - 11 amp circuits, AUX1 and AUX2. (...now I don't
know exactly how those 2 circuits can be combined, but something tells
me there's a way which is simple and direct...)
Second, the Revision XX diagram shows the EXP Avionics
Bus powering the E-bus (endurance) from a 7 amp circuit. (...btw, I
don't understand the notion that we should be rid of the avionics master
switch...). Also...note that w/ Skyview and the back up GPS both having
their own back up batteries, if either the Master switch or the Avionics
Master is turned off and the E-bus Alternate Feed is energized, we'll be
back in business w/ a full suite of avionics.
It strikes me that this approach is elegant, simple, and
direct; I shudder at the thought of altering any part of the circuitry
within the EXP Bus other than changing some Fast-on spades of a couple
of switches and relabeling them.
I'm baffled when you write,
> Old avionics bus becomes e-bus.
...as I look at the circuit board of the EXP Bus, I
haven't a clue how this can happen and create the alternate feed
intrinsic w/ the e-bus concept...way outside my comfort zone to poke
around in that circuit board.
Fred
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