Today's Message Index:
----------------------
1. 04:05 AM - 555088-160 Air Jordan 1 Retro High OG Sail Red (blair2019)
2. 07:36 AM - Re: Overvoltage protection and other stuff (Robert L. Nuckolls, III)
3. 11:47 AM - Re: Overvoltage protection and other stuff (Alec Myers)
4. 03:52 PM - Re: Overvoltage protection and other stuff (Art Zemon)
5. 04:20 PM - Re: Overvoltage protection and other stuff (Alec Myers)
6. 05:01 PM - John Deere Generator pulses (Ernest Christley)
7. 05:31 PM - Narco Com-11 sidetone (N804RV)
8. 06:28 PM - Re: John Deere Generator pulses (user9253)
9. 09:59 PM - Re: Connectors (N804RV)
Message 1
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| Subject: | 555088-160 Air Jordan 1 Retro High OG Sail Red |
It seems that this year's sneakers still can't escape the "Devil's Palm" of Air Jordan 1! Today, we just ushered in the release of the first Air Jordan 1 in 2019, and another new color scheme has surfaced! (https://www.2019mensjordans.com/product-category/air-jordan-1/)Air Jordan 1 Retro High OG Sail Red uses an extraordinarily vibrant white and red color. The white leather upper is complemented by red details and car lines. It also has a "two yuan" brush style! Flying wing logo, tongue embroidery label, this classic element is available, standard OG first year details. It will be officially released on March 16th, whether it is directly on the foot to cater to the bright sunshine in spring, or used for custom-made shoes, all of them are of good quality!
Jordans 2019 Shoes (https://www.jordans2019shoes.com),Since the second half of last year, there have been a number of Foamposite foam materials to create the AF1 debut, and this time it is a high-top style! The Nike Air Force 1 Foamposite Cup NA Red is not only a unique bubble material, but also a dazzling all-red dress. Even the AF1 high-top shoe-shaped ankle straps are preserved. Although it is a pure red tone, the gloss effect of the upper and the matching of different materials still have a good visual level.
In addition to the recent Tianjin spray theme, the Nike Sneakers (https://www.2019sneakersrelease.com/product-category/nike-sneakers/) brings us another surprise Nike Air Max 98, which is the white and red color. Similar to the Supreme sky-price co-branded style, this pair of Nike Air Max 98 is decorated with vibrant red in a white background. It is absolutely versatile and full of energy, making it easy to create a vibrant and energetic effect.
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=487384#487384
Message 2
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| Subject: | Re: Overvoltage protection and other stuff |
At 03:43 PM 2/1/2019, you wrote:
>
>Bob et al.
>
>I=99m working with my engineering representative
>to modify a TC aircraft to replace a 28V Gill
>flooded battery with a pair of 12V Odyssey AGM in a different location.
>The new location while not =9Csealed=9D, is not
>provided with ventilation to the outside.
>
>Today=99s task is to demonstrate the new
>installation will comply with 23.1353(d) which reads:
>"No explosive or toxic gases emitted by any
>battery in normal operation, or as the result of
>any probable malfunction in the charging system
>or battery installation, may accumulate in
>hazardous quantities within the airplane.=9D
There HAVE been H-O explosions associated with
SVLA batteries. The only two I've been privy
to were (1) an internal explosion on a 44AH
bizjet battery that suffered an open, inter-cell
weld in the top of the battery. The explosion
cracked the case but did not cause damage
to the aircraft.
A second case was in a GlasAir fitted with
a battery box behind the passenger seat. The
battery contactor was inside the box too.
The battery had been subjected to a sustained
ov condition. The pilot was engaged in some
exploratory, switch-flipping diagnostics
that ignited the trapped gasses inside the
battery box and blew it up.
The WORST policy for dealing with an
outgassing battery is to enclose it. The
battery box was originally intended to
conduct SPILLS over overboard. It had
nothing to do with venting of gasses.
The abused SLVA battery is LEAST likely
to provoke a bad day in the cockpit by
strapping it down to an open tray. Any
dangerous gasses that do escape the
battery simply waft away. Explosions
occur when fuel is ignited within a
tightly closed space.
If 'fuel' is generated by an abused battery,
the best prophylactic against explosion
is to let it waft way. It won't explode
or burn even if you ARE a smoker.
>After conversation with Odyssey and after
>reading their and other technical material I am
>happy to argue that the only =9Cprobable=9D
>malfunction in the charging system or battery
>installation that could result in a release of a
>hazardous quantity of gas would be a prolonged
>over-voltage event (>30V for the two batteries
>in series). That would release some quantity of hydrogen.
Not the point. Proper conduct of FMEA
considers ONLY one failure at a time.
Assume that the battery WILL be abused
as some point in the future. Then eliminate
probability that the failure escalates
into a more excited situation or propagation
out to the rest of the system.
Strap it down in the open air and you're
good to go.
>The aircraft charging system is based on a Bosch
>28V automotive alternator; I don=99t have any
>technical details of whether it has any inbuilt
>over-voltage protection. The Approved Flight
>Manual indicates that an over-voltage condition
>has to be noticed by the pilot and pilot action
>is required to take the alternator off-line
>manually by pulling the c/b. So it=99s probable
>there=99s no automatic protection included.
>
>To demonstrate that I=99m compliant with
>23.1353(d) I=99m thinking of including in the
>modification the installation of a crowbar
>protection module on the alternator field coil.
>
>So=85 to get to the question=85 can anyone suggest a
>part number/supplier for a 28V OV module (30V
>trigger voltage)? Ideally one that is already in
>use on a TC airplane somewhere, which will make
>it easier to have that part approved as part of the modification.
>.
>
>Or are there any other ways I could provide comfort with respect to
23.1353?
Adding ov protection is called for
by FMEA on the alternator irrespective
of any other components on the aircraft.
For decades, builders and some manufactures
have modified internally regulated alternators
to (1) remove internal regulators and (2)
install legacy regulator/ov protection.
I'll suggest that the confident fast-track
is to do that mod to the alternator and install
a regulator qualified for TC aircraft like
https://tinyurl.com/yb6o5vtn
or for OBAM aircraft
https://tinyurl.com/y9tlkpyo
Depending on your airplane's station in
the aviation hierarchy.
Both of these examples will come with
OV protection . . . the B&C product
also offers OV annunciation.
Bob . . .
Message 3
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| Subject: | Re: Overvoltage protection and other stuff |
> Strap it down in the open air and you're
good to go.
It is (they are) going to be located under the seat. The airframe is composite,
and the seat frame is part of the airframe, forming a well, but the seat top
doesnt seal tight, so lets assume that that the seat void is adequately ventilated
for lighter-than-air gas to the rest of the cabin. Being a modern airframe,
the cabin is relatively leak and draught free. The bubble canopy seals well
with a rubber cushion all the way around. When the cabin ventilation system is
shut off, there are no draughts.
The lower explosive limit for Hydrogen is 4%. Taking a factor of 4 safety, and
assuming a cabin volume of 3m^3, a hazardous amount of H2 is 30 litres.
Outgassing from all lead acid batteries during a significant over voltage event
is 7.6ml H2 / cell / amp / minute. RG technology works great to reduce outgassing
at low charge rates but isnt a lot of use at high currents.
The alternator is fitted with a 30A breaker. The worst case continuous release
of hydrogen would occur when the alternator produces a voltage sufficient to charge
the already-charged battery with a current of exactly 30A. Any more and
the breaker will trip.
There are 12 cells between the two batteries. That means that the worst case production
of H2 is 2.7 litres / minute. A hazardous environment would follow, for
regulatory purposes, in approximately 10-15 minutes, assuming no ventilation.
I am *not* permitted to assume that the pilot will take the appropriate corrective
action within that period and shut down the alternator. If I want to claim
that the level of cabin ventilation is guaranteed to vent hydrogen at a rate
sufficient to prevent buildup of 30l of H2 in that sort of time frame, I will
have to justify that with adequate data.
Alternatively if there is an over-voltage trip that prevents the bus voltage rising
above 32V, then the battery would have to be limiting the overcharging current
to less than 4A. The time to a hazardous buildup of H2 in the cabin would
be 7.5 times greater, or more than one hour.
At a current of 4A, I can carry out an experiment with the proposed battery and
a power supply in the actual aircraft in a hangar, in still air conditions, to
measure the cabin H2 concentration rate of rise. (I dont think I could find
a power supply with sufficient voltage overhead to force 30A through a lead acid
battery, nor would I feel comfortable doing so.)
Another way to satisfy regulatory requirement is to use a Concorde RG-11M that
has a manifold and a vent tube. I can connect the vent tube to the original vent
provided for the flooded battery, and the requirement is satisfied because
all gas will vent to the outside. The disadvantages are that its a lot more expensive
than two odyssey batteries. And at 27lbs, harder to mount.
>> I'll suggest that the confident fast-track
is to do that mod to the alternator and install
a regulator qualified for TC aircraft like
There is merit in this idea, but I am concerned about project creep. To the extent
that the existing IR alternator passed certification, its not an absolute
requirement to upgrade it.
On Feb 2, 2019, at 10:36 AM, Robert L. Nuckolls, III <nuckolls.bob@aeroelectric.com>
wrote:
At 03:43 PM 2/1/2019, you wrote:
>
> Bob et al.
>
> Im working with my engineering representative to modify a TC aircraft to replace
a 28V Gill flooded battery with a pair of 12V Odyssey AGM in a different location.
> The new location while not sealed, is not provided with ventilation to the outside.
>
> Todays task is to demonstrate the new installation will comply with 23.1353(d)
which reads:
> "No explosive or toxic gases emitted by any battery in normal operation, or as
the result of any probable malfunction in the charging system or battery installation,
may accumulate in hazardous quantities within the airplane.
There HAVE been H-O explosions associated with
SVLA batteries. The only two I've been privy
to were (1) an internal explosion on a 44AH
bizjet battery that suffered an open, inter-cell
weld in the top of the battery. The explosion
cracked the case but did not cause damage
to the aircraft.
A second case was in a GlasAir fitted with
a battery box behind the passenger seat. The
battery contactor was inside the box too.
The battery had been subjected to a sustained
ov condition. The pilot was engaged in some
exploratory, switch-flipping diagnostics
that ignited the trapped gasses inside the
battery box and blew it up.
The WORST policy for dealing with an
outgassing battery is to enclose it. The
battery box was originally intended to
conduct SPILLS over overboard. It had
nothing to do with venting of gasses.
The abused SLVA battery is LEAST likely
to provoke a bad day in the cockpit by
strapping it down to an open tray. Any
dangerous gasses that do escape the
battery simply waft away. Explosions
occur when fuel is ignited within a
tightly closed space.
If 'fuel' is generated by an abused battery,
the best prophylactic against explosion
is to let it waft way. It won't explode
or burn even if you ARE a smoker.
> After conversation with Odyssey and after reading their and other technical material
I am happy to argue that the only probable malfunction in the charging
system or battery installation that could result in a release of a hazardous
quantity of gas would be a prolonged over-voltage event (>30V for the two batteries
in series). That would release some quantity of hydrogen.
Not the point. Proper conduct of FMEA
considers ONLY one failure at a time.
Assume that the battery WILL be abused
as some point in the future. Then eliminate
probability that the failure escalates
into a more excited situation or propagation
out to the rest of the system.
Strap it down in the open air and you're
good to go.
> The aircraft charging system is based on a Bosch 28V automotive alternator; I
dont have any technical details of whether it has any inbuilt over-voltage protection.
The Approved Flight Manual indicates that an over-voltage condition
has to be noticed by the pilot and pilot action is required to take the alternator
off-line manually by pulling the c/b. So its probable theres no automatic
protection included.
>
> To demonstrate that Im compliant with 23.1353(d) Im thinking of including in
the modification the installation of a crowbar protection module on the alternator
field coil.
>
> So> to get to the question> can anyone suggest a part number/supplier for a
28V OV module (30V trigger voltage)? Ideally one that is already in use on a
TC airplane somewhere, which will make it easier to have that part approved as
part of the modification.
> .
>
> Or are there any other ways I could provide comfort with respect to 23.1353?
Adding ov protection is called for
by FMEA on the alternator irrespective
of any other components on the aircraft.
For decades, builders and some manufactures
have modified internally regulated alternators
to (1) remove internal regulators and (2)
install legacy regulator/ov protection.
I'll suggest that the confident fast-track
is to do that mod to the alternator and install
a regulator qualified for TC aircraft like
https://tinyurl.com/yb6o5vtn
or for OBAM aircraft
https://tinyurl.com/y9tlkpyo
Depending on your airplane's station in
the aviation hierarchy.
Both of these examples will come with
OV protection . . . the B&C product
also offers OV annunciation.
Bob . . .
Message 4
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| Subject: | Re: Overvoltage protection and other stuff |
On Sat, Feb 2, 2019 at 2:04 PM Alec Myers <alec@alecmyers.com> wrote:
> It is (they are) going to be located under the seat. The airframe is
> composite, and the seat frame is part of the airframe, forming a well, bu
t
> the seat top doesn=99t seal tight,
Alec,
How about a low tech solution? Add a small vent from the well to the
outside of the fuselage so that, whenever the airplane is in motion, low
pressure on the outside draws air past the seat top, past the batteries,
and out.
-- Art Z.
--
https://CheerfulCurmudgeon.com/
*"Be kind, for everyone you meet is fighting a hard battle."*
Message 5
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| Subject: | Re: Overvoltage protection and other stuff |
I love low-tech! I dont think thats definitive enough for the powers that be, however.
And I dont think my structures person will enjoy me drilling holes in
a composite stressed fuselage just for a look see.
On the subject of over-voltage trips, I have discovered that both Carling and Sensata
(Klixon) make circuit breakers with, for instance, a second coil that you
can use to trip the breaker via an isolated circuit (that could easily be triggered
by an over-voltage, in addition to the regular over-current coil. So
one of those could be used to replace the b-lead CB. It will be a challenge to
find small quantities of what is a very specialized part though.
On Feb 2, 2019, at 5:42 PM, Art Zemon <art@zemon.name> wrote:
On Sat, Feb 2, 2019 at 2:04 PM Alec Myers <alec@alecmyers.com> wrote:
It is (they are) going to be located under the seat. The airframe is composite,
and the seat frame is part of the airframe, forming a well, but the seat top
doesnt seal tight,
Alec,
How about a low tech solution? Add a small vent from the well to the outside of
the fuselage so that, whenever the airplane is in motion, low pressure on the
outside draws air past the seat top, past the batteries, and out.
-- Art Z.
--
https://CheerfulCurmudgeon.com/
"Be kind, for everyone you meet is fighting a hard battle."
Message 6
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| Subject: | John Deere Generator pulses |
I'm using the pulses from my John Deere generator for my tack signal into m
y EIS.=C2- Everything is working fine, and I've got a good solid signal.
=C2- However, I'm not positive that I have it calibrated correctly.=C2-
If someone with a JD generator that isn't mounted could tell me how many p
ulses it makes for each revolution, I'd be very thankful.
Message 7
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| Subject: | Narco Com-11 sidetone |
Anyone know if the Narco com-11 had sidetone?
--------
Ken W.
N804RV(reserved)
RV-8 Empennage in work
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=487398#487398
Message 8
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| Subject: | Re: John Deere Generator pulses |
What kind of engine?
Is the generator gear driven or belt driven?
How about using an optical tachometer to compare to the EIS?
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=487401#487401
Message 9
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Here's what they are:https://youtu.be/XD1JDk1tCj4
This is the crimper you need to do it right: https://www.skygeek.com/dmc-tools-gmt232-commercial-crimp-tool-ad-1377.html?utm_source=googlebase&utm_medium=shoppingengine&utm_content=dmc-tools-gmt232-commercial-crimp-tool-ad-1377&utm_campaign=froogle&gclid=Cj0KCQiAnNXiBRCoARIsAJe_1cqpHgVAOlO0Ex-17snk3-lP0mvnmXVpE2YwSNUGU0P1KG_mrkt7ougaAgj7EALw_wcB
--------
Ken W.
N804RV(reserved)
RV-8 Empennage in work
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=487403#487403
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