Today's Message Index:
----------------------
0. 07:22 AM - Reminder (Matt Dralle)
1. 12:50 AM - Re: z13/8 ess bus feed (mmcelrea)
2. 03:42 AM - Z-13/8 inquiry (bcone1381)
3. 05:31 AM - Re: Double stick foam anchors (Harley Dixon)
4. 05:55 AM - Re: Double stick foam anchors (Kelly McMullen)
5. 05:56 AM - Re: Z-13/8 inquiry (user9253)
6. 06:05 AM - Double stick foam anchors (MLE)
7. 06:28 AM - Re: Double stick foam anchors (Art Zemon)
8. 07:12 AM - Re: Double stick foam anchors (Robert Reed)
9. 08:33 AM - Re: Z-13/8 inquiry (Robert L. Nuckolls, III)
10. 08:44 AM - Re: Double stick foam anchors (Robert L. Nuckolls, III)
11. 08:47 AM - Re: Re: z13/8 ess bus feed (Robert L. Nuckolls, III)
12. 09:32 AM - Re: Z-13/8 inquiry (bcone1381)
13. 10:37 AM - Generator to Alt on Cessna210 (Ron Burnett)
14. 11:13 AM - Re: Double stick foam anchors (Art Zemon)
15. 11:31 AM - Re: Generator to Alt on Cessna210 (Robert L. Nuckolls, III)
16. 11:45 AM - Re: Double stick foam anchors (Robert L. Nuckolls, III)
17. 09:45 PM - Re: Simple EFIS backup battery wiring (Eric Page)
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Dear Listers,
A quick reminder that November is the annual Matronics List Fund Raiser. The Lists
are 100% member supported and all of the operational costs are covered solely
through your Contributions during this time of the year.
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Thank you in advance!
Matt Dralle
Matronics Email List and Forum Administrator
Message 1
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| Subject: | Re: z13/8 ess bus feed |
Is the SD8 on/available during normal flight? If the output is fed through a diode
would that prevent the alternators 'competing' or is the voltage set at lower
level than the main alternator and monitoring voltage and amps output from
both alternators?
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=474981#474981
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In the beginning phase of planning the architecture of my electrical system. I
have never done this before, and appreciate your mentoring. I have two questions
for you after reading thru the background for the questions
The 12th edition of the Aero Electric Connection book Chapter 17 is titled Electrical
System Reliability. In this CH, Bob introduces us to a Cessna electrical
system, then provides reliability improvements. Bob expands the Avionics Bus
to serve as an Essential Bus, and then replaces the Cessna avionics master
with a diode for its normal power feed.
The alternate power feed from the Battery to the Essential Bus shown in the CH17
example is a simple switch. This improvement over the Cessna system removes
the 1 amp draw of the Batter Contactor. Thats Great, I love it.
But, when I check out the Z-13/8 diagram, it shows an S704-1 relay....supplied
by B&C.
Questions:
1) Why don't we use a switch as discussed in Ch 17?
2) What is the amp draw of this Relay? Maybe thats a Q. for B&C
--------
Brooks Cone
Bearhawk Patrol Kit Build
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=474982#474982
Attachments:
http://forums.matronics.com//files/screen_shot_2017_11_15_at_62544_am_126.png
http://forums.matronics.com//files/screen_shot_2017_11_15_at_61506_am_139.png
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| Subject: | Re: Double stick foam anchors |
3M Extreme Mounting Tape 13M Extreme Mounting Tape 1
I removed the sticky stuff on some of mine that were coming loose and
replaced them with "Scotch Extremely Strong" mounting tape. So far so good!
Harley
On 11/14/2017 11:08 PM, Paul Kuntz wrote:
> If you use just the sticky back foam mounting, any constant load, even
> small, will eventually pull free. As suggested by a previous post, I
> just scrape off the foam backing, roughen the surface with coarse
> sandpaper and mount the pads with JB Weld. It takes a few minutes but
> youll only do it once.
>
> On Tue, Nov 14, 2017 at 20:01 Tim Yoder <ftyoder@yoderbuilt.com
> <mailto:ftyoder@yoderbuilt.com>> wrote:
>
> Or remove the adhesive and use JB Weld.
>
> Tim
>
> *From:* owner-aeroelectric-list-server@matronics.com
> <mailto:owner-aeroelectric-list-server@matronics.com>
> [mailto:owner-aeroelectric-list-server@matronics.com
> <mailto:owner-aeroelectric-list-server@matronics.com>] *On Behalf
> Of *ashleysc@broadstripe.net <mailto:ashleysc@broadstripe.net>
> *Sent:* Tuesday, November 14, 2017 8:05 PM
> *To:* aeroelectric-list@matronics.com
> <mailto:aeroelectric-list@matronics.com>
> *Subject:* Re: AeroElectric-List: Double stick foam anchors
>
> Hi Art;
>
> I have tried these (or something like them). The ones I tried had
> the adhesive already applied. Some of them came unstuck after a
> while. If there is a way to put a small rivet through the center,
> I would do it.
>
> Cheers! Stu.
>
> ------------------------------------------------------------------------
>
> *From: *"Art Zemon" <art@zemon.name <mailto:art@zemon.name>>
> *To: *aeroelectric-list@matronics.com
> <mailto:aeroelectric-list@matronics.com>
> *Sent: *Tuesday, November 14, 2017 6:54:58 PM
> *Subject: *AeroElectric-List: Double stick foam anchors
>
> Folks,
>
> Is there any reason why I should not use one of these anchors with
> the double stick foam in a position such as this?
>
> -- Art Z.
>
> Sent from my phone. Please excuse brevity and bizarre typos.
>
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| Subject: | Re: Double stick foam anchors |
That tape is extremely strong...very hard to remove(but not as permanent
as JB Weld). It is commonly found in auto parts stores labeled for
mounting body trim strips.
On 11/15/2017 6:23 AM, Harley Dixon wrote:
> 3M Extreme Mounting Tape 13M Extreme Mounting Tape 1
> I removed the sticky stuff on some of mine that were coming loose and
> replaced them with "Scotch Extremely Strong" mounting tape. So far so good!
>
> Harley
>
> On 11/14/2017 11:08 PM, Paul Kuntz wrote:
>> If you use just the sticky back foam mounting, any constant load, even
>> small, will eventually pull free. As suggested by a previous post, I
>> just scrape off the foam backing, roughen the surface with coarse
>> sandpaper and mount the pads with JB Weld. It takes a few minutes but
>> youll only do it once.
>>
Message 5
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| Subject: | Re: Z-13/8 inquiry |
A relay can be used for remote control. That allows the circuit to be shut off
near the battery without running always-hot wires into the cockpit. Shutting
off power near the source is important in case of smoke in the cockpit or in
case of an imminent forced landing.
A small switch can control a relay. A relay can control a larger current.
The relay manufacturer's data sheet will state the current draw. I think that
the current will be less than 1/10 amp.
--------
Joe Gores
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=474985#474985
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| Subject: | Double stick foam anchors |
I've been using a dab of "shoe glue" right on the anchors without removing
their adhesive. Seems to work. Shoe glue is tough stuff but can be
removed if needed unlike JB Weld.
Marty
Time: 06:57:00 PM PST US
From: Art Zemon <art@zemon.name>
Subject: AeroElectric-List: Double stick foam anchors
Folks,
Is there any reason why I should not use one of these anchors with the
double stick foam in a position such as this?
-- Art Z.
Sent from my phone. Please excuse brevity and bizarre typos
Message 7
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| Subject: | Re: Double stick foam anchors |
I suppose that I could use a squirt of RTV, too. In the spots that I am
considering, there are only a few wires and there will be no significant
force pulling on the mount.
Thanks for the feedback, folks.
Cheers,
-- Art Z.
On Wed, Nov 15, 2017 at 7:53 AM, Kelly McMullen <kellym@aviating.com> wrote:
> kellym@aviating.com>
>
> That tape is extremely strong...very hard to remove(but not as permanent
> as JB Weld). It is commonly found in auto parts stores labeled for mounting
> body trim strips.
>
> On 11/15/2017 6:23 AM, Harley Dixon wrote:
>
>> 3M Extreme Mounting Tape 13M Extreme Mounting Tape 1
>
>
--
https://CheerfulCurmudgeon.com/
*"If I am not for myself, who is for me? And if I am only for myself, what
am I? And if not now, when?" Hillel*
Message 8
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| Subject: | Re: Double stick foam anchors |
It really isn't the amount of force that will do them in but the changes in
temperature, vibration, and TIME.=C2- Some may hold for a while but if y
ou really want them to stay, remove the foam stick tape and bond them with
adhesive.=C2- I have them installed throughout the inside of my plane and
all have been bonded in place.=C2- Have tried to remove a couple of them
and they are in place permanently.=C2- It takes maybe a minute extra per
but well worth the effort in the long run, especially if they are in tight
places that are hard to get to later on.
Bob
From: Art Zemon <art@zemon.name>
To: aeroelectric-list@matronics.com
Sent: Wednesday, November 15, 2017 8:29 AM
Subject: Re: AeroElectric-List: Double stick foam anchors
I suppose that I could use a squirt of RTV, too. In the spots that I am con
sidering, there are only a few wires and there will be no significant force
pulling on the mount.
Thanks for the feedback, folks.
Cheers,=C2- =C2- -- Art Z.
On Wed, Nov 15, 2017 at 7:53 AM, Kelly McMullen <kellym@aviating.com> wrote
:
m>
That tape is extremely strong...very hard to remove(but not as permanent as
JB Weld). It is commonly found in auto parts stores labeled for mounting b
ody trim strips.
On 11/15/2017 6:23 AM, Harley Dixon wrote:
3M Extreme Mounting Tape 13M Extreme Mounting Tape 1
--
https://CheerfulCurmudgeon.com/
"If I am not for myself, who is for me? And if I am only for myself, what a
m I? And if not now, when?" Hillel
Message 9
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| Subject: | Re: Z-13/8 inquiry |
At 05:41 AM 11/15/2017, you wrote:
>
>In the beginning phase of planning the architecture of my electrical
>system. I have never done this before, and appreciate your
>mentoring. I have two questions for you after reading thru the
>background for the questions
>
>The 12th edition of the Aero Electric Connection book Chapter 17 is
>titled Electrical System Reliability. In this CH, Bob introduces us
>to a Cessna electrical system, then provides reliability
>improvements. Bob expands the Avionics Bus to serve as an Essential
>Bus, and then replaces the Cessna avionics master with a diode for
>its normal power feed.
>
>The alternate power feed from the Battery to the Essential Bus shown
>in the CH17 example is a simple switch. This improvement over the
>Cessna system removes the 1 amp draw of the Batter Contactor. Thats
>Great, I love it.
>
>But, when I check out the Z-13/8 diagram, it shows an S704-1
>relay....supplied by B&C.
>
>Questions:
>1) Why don't we use a switch as discussed in Ch 17?
>2) What is the amp draw of this Relay? Maybe thats a Q. for B&C
The e-bus was, as far as I can remember, first
installed on a LongEz about 1985. I was talking
with a reader one night on the phone. He was in
California if memory serves. His engine driven power
source was the SD8 alternator . . .
We were discussing his load analysis
http://tinyurl.com/9rt6ymn
http://tinyurl.com/7jqypwj
While running through the list of electro-
whizzies needed for comfortable continuation
of flight. battery only, to intended destination,
a major component of electrical loads was
the battery contactor . . . it's current
draw after warm up and at battery only voltages
was on the order of 0.6A.
http://tinyurl.com/mpcgp3t
http://tinyurl.com/k6bwdqo
Contactor power would not be available to run endurance
loads during battery only operations.
During that conversation, we crafted what
started out as an 'essential' bus but later
corrected to 'endurance' bus. The goal
during that conversation was to craft a system
whereby a long distance flight would NOT be
limited not by battery capacity but by fuel
aboard.
As I recall, his endurance loads were finally
pared down to about 2.2 amps. His design goal
for battery only ops was 4 hours. This meant
that a battery at end of service life had to
support his 2.2A load for 4 hours. If end
of service life was 75% of new capacity, then
a new battery needed to support 2.2A for
at least 5.5 hours.
I don't recall what constellation of battery products
were in popular consideration back then but let
us suppose that same conversation was today and
the Hawker PC680 was one of several candidates
under consideration.
Emacs!
Here we see that a 2.2A load on a new battery is good for
5 hours . . . barely adequate to the design goal. Leaving
a 0.6A battery contactor load in the mix would have dropped
new battery endurance to 4 hours.
The endurance bus with dual feed paths was birthed that
evening. The 2.2A endurance load could be tapped directly
from the battery bus through a fuse of 7.5 amps or less.
This brings up another design goal for making direct
connections to batteries. The legacy design conventions
in type certified aircraft called for always hot feeders to
be protected at no more than 5A. The idea was to limit
the battery's ability to start fires in the event of
a landing that was really hard to walk away from.
TC designs for taking power away from the battery at
greater current levels had to be crew controlled
like the battery contactor. As our OBAM aircraft
evolved, some design goals called for e-bus loads
exceeding that which could be carried on 7.5A fuse
(we adopted 7A over the 5A figure because fuses
are MANY times faster than breakers).
So you see, there is no cookie-cutter answer to
your question. Using an e-bus alternate feed
relay is a decision driven by (1) establishment
of design goals for flight in the endurance
mode (2) selection hardware you're going to run
in the endurance mode, (3) selecting battery
capacity to meet the goal and (4) PERIODIC MAINTENANCE
checks to MAINTAIN the battery at the required
capacity.
This conversation took place years before Z13/8 . . .
a time when vacuum pumps were being installed
on large numbers of OBAM aircraft. As the such-n-blow
instruments began to disappear from the panels, the
vacuum pump pad became the ideal real estate for
installing a SECOND engine driven power source and
the SD8 was an obvious choice.
Z13/8 was crafted to exploit that real estate
and allow the builder to craft an e-bus load
value on the order of 8A. Battery capacity was
no longer the primary consideration for endurance
after loss of main alternator.
Hence the development of Z32 which installs a relay
to serve as a kind of mini-battery contactor that
gives the crew direct control over that feeder
AT THE BATTERY protected by a 10A fuse.
It follows that the relay (which draws about 0.1A)
is only needed if e-bus loads exceed 5A or so in
the ENDURANCE mode . . . in the case of Z13/8,
maximum endurance load without taxing the battery
is 8A and the feeder is a bit fatter wire. So
the e-bus alternate feed relay became a permanent
feature in Z13/8 revision T.
Bob . . .
Message 10
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| Subject: | Re: Double stick foam anchors |
At 08:03 AM 11/15/2017, you wrote:
>I've been using a dab of "shoe glue" right on
>the anchors without removing their
>adhesive.=C2 Seems to work.=C2 Shoe glue is tough
>stuff but can be removed if needed unlike JB Weld.
Sho Goo, like its industrial cousin E6000 was
the adhesive of choice for crafting and installing
bond studs to surfaces without drilling holes.
http://tinyurl.com/ydasnwk9
http://tinyurl.com/j2gxbqy
Early studies for suitable adhesives included
JB weld but while it does get a good grip
on things, it's not as compliant nor
does it adhere to slick and/or plastic
surfaces as the E6000. My adhesive of
choice would be the E6000.
3M does produce VHB (very high bond) mounting
tapes that are quite strong
http://tinyurl.com/ydfql26k
Run some tests with any alternative adhesive.
Bond the part down. Wait 24 hours and then
pull it off. What breaks first and how
hard was it to get it off.
Generally speaking, bonded on fasteners
should be used only for non-structural,
low risk security on wire bundles, coax
feeders, perhaps NylaFlo pitot or static
pressure lines.
Bob . . .
Message 11
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| Subject: | Re: z13/8 ess bus feed |
At 02:50 AM 11/15/2017, you wrote:
>
>Is the SD8 on/available during normal flight? If the output is fed
>through a diode would that prevent the alternators 'competing' or is
>the voltage set at lower level than the main alternator and
>monitoring voltage and amps output from both alternators?
You can run it during normal flight . . . but why?
It's a STANDBY alternator that demonstrates exceptional
reliability by sitting there doing NOTHING until
pressed into service as a consequence of main
alternator failure.
It should be pre-flight tested . . . but allowed
to sit in cold repose waiting for the rare failure
of the main alternator.
Bob . . .
Message 12
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| Subject: | Re: Z-13/8 inquiry |
I feel like I am starting to dissect an onion....so many layers. Your explanation
of the TC design goals makes clear the need for the contractor.
The Load analysis information you just shared must be my next path to start exploring.
This will be ton of fun to figure out.
Thanks so much.
I know of nowhere that an aircraft builder can get clear answers to questions based
on truth and principle and void of opinion and heresy.
--------
Brooks Cone
Bearhawk Patrol Kit Build
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=475072#475072
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| Subject: | Generator to Alt on Cessna210 |
A friend is replacing his generator with a certified Plane Power Alternator and
PP regulator. We are wondering if the noise filter is built in the FAA/PMA alternator?
If so, the fat wires from the alternator could be bolted to the fat wire from the
noise filter that runs to the panel.
This is a PMA approved part and will be signed off and inspected. My friend is
trying to do the hook up beforehand.
Thanks for any help
Ron Burnett
May you have the Lord's blessings today!
Sent from my iPad
Message 14
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| Subject: | Re: Double stick foam anchors |
Bob,
That's exactly the situation I have. There are a few places where I want to
secure a small wire bundle and the most convenient thing to attach it to is
the .025 aluminum skin of the plane. There are also a couple of places
where I want to tie up a single coax and there is no rigid structure.
Cheers,
-- Art Z.
On Wed, Nov 15, 2017 at 10:43 AM, Robert L. Nuckolls, III <
nuckolls.bob@aeroelectric.com> wrote:
>
> Generally speaking, bonded on fasteners
> should be used only for non-structural,
> low risk security on wire bundles, coax
> feeders, perhaps NylaFlo pitot or static
> pressure lines.
>
--
https://CheerfulCurmudgeon.com/
*"If I am not for myself, who is for me? And if I am only for myself, what
am I? And if not now, when?" Hillel*
Message 15
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| Subject: | Re: Generator to Alt on Cessna210 |
At 12:15 PM 11/15/2017, you wrote:
>
>A friend is replacing his generator with a certified Plane Power
>Alternator and PP regulator. We are wondering if the noise filter
>is built in the FAA/PMA alternator?
If no noise filter is supplied, then it's
presumed not necessary unless demonstrated
in subsequent flight testing.
>If so, the fat wires from the alternator could be bolted to the fat
>wire from the noise filter that runs to the panel.
>
>This is a PMA approved part and will be signed off and
>inspected. My friend is trying to do the hook up beforehand.
Install per instructions which are part
of the STC/PMA . . . if no noise filter is
included then it's not necessary.
Bob . . .
Message 16
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| Subject: | Re: Double stick foam anchors |
At 01:11 PM 11/15/2017, you wrote:
>Bob,
>
>That's exactly the situation I have. There are a few places where I
>want to secure a small wire bundle and the most convenient thing to
>attach it to is the .025 aluminum skin of the plane. There are also
>a couple of places where I want to tie up a single coax and there is
>no rigid structure.
yup . . . that's what the bond studs are all
about. We used them in production on a number
of models at Beech. But these were "qualified"
parts that were two orders of magnitude more
expensive than a McMaster-Carr stud stuck to
the aircraft with E6000.
I've got no heartburn with the Nylon cable mounts.
If one were to seek out the epitome of this
methodology you would look for products like this:
6/6 black nylon, very high bond adhesive pads.
I've not been able to find anyone offering less
than bags of 100. Here's one offering from
Allied Electronics.
http://tinyurl.com/y7qjqy2m
Digikey has them too but higher priced
and lots of 100 minimum
http://tinyurl.com/y7rel4q4
Perhaps a few builders could team up and
buy a bag to split.
Bob . . .
Message 17
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| Subject: | Re: Simple EFIS backup battery wiring |
mrcc1234(at)sbcglobal.net wrote:
> I need to install a small battery on my MGS Extreme so that it can be kept up
and running during engine start for my VFR 601XL. I would like to keep the wiring
as simple as possible, but also allow the 1.2 AH battery to be maintained
by the alternator. MGL has an example that uses a diode and switch to power the
backup pin on another system, but the Extreme does not include this.
> How has everyone else handled this?
First, let me say: full credit to Eric Jones. What follows is thanks to his design
and prototyping work.
About four years ago when this topic came up...
...on the second page here: http://forums.matronics.com/viewtopic.php?t=98976
...then continued here: http://forums.matronics.com/viewtopic.php?t=99301
...and here: http://forums.matronics.com/viewtopic.php?t=99555
...Eric Jones designed a "De-Slumpifier" or voltage slump eliminator circuit using
supercapacitors (see his schematic at the second link above, and mine attached
below). Another forum member (Joe, "user9253") successfully tested Eric's
prototype in his RV-12, but Eric decided that additional capacitance was needed.
I've adapted Eric's design to increase capacitance from 0.25F to 0.55F and to match
the balance resistors to the new capacitors' leakage current specification.
Otherwise, the design is largely unchanged. I've also prepared a circuit
board layout, so that the device can be easily duplicated by anyone who needs
it.
If you're trying to prevent EFIS/EMS brownout/reboot during engine start, this
will do the trick. Note, however, that this device is not an endurance supply
and it won't support a load in the event of bus failure or shutdown. The device
would cost about $40 to build, and it would eliminate the periodic testing
and replacement associated with a battery installation. It's designed to fit
a 2" x 2-3/4" box, and it will weigh just a few ounces.
Operation is simple: apply bus power and ground to the input, and route output
power and ground to the EFIS/EMS. Assuming a fully charged battery at ~12.7V,
the bus will charge the capacitors to ~12.3V within 20 seconds once power is
applied. During engine cranking, the capacitors will power the EFIS/EMS at >8V
(minimum for the MGL Xtreme units) for ~13 seconds, assuming a 2.8W load. [The
MGL Xtreme manuals specify power draw of 130mA at 13.8V for the EMS and 200mA
at 13.8V for the EFIS; the latter equals 2.8W.] Assuming a healthy battery
and an engine that starts within a few seconds, your EFIS/EMS won't brownout/reboot.
You can order the parts and assemble it yourself, or I'd be happy to do it for
you for the cost of parts and postage. Here's a link for a .ZIP file on my Google
Drive that contains my DipTrace CAD files, as well the RS-274X Gerber files
needed to order the printed circuit board: https://preview.tinyurl.com/yajod9m6
If you'd like some guidance on ordering the boards and components --or-- if you'd
like me to assemble one and send it to you, just let me know. It would take
2-3 weeks, so you'd have it within a month or so.
If anyone else wants one, just chime in. Up to ten copies will not increase the
cost of PCB production, so I can make several for just the incremental cost
of components.
Eric
P.S. A few items to note if you assemble this yourself:
1. Diode D1 is a bidirectional transient voltage suppressor. It can be installed
in either direction, regardless of its markings.
2. Diodes D2-D4 are installed standing on end, with the cathode (white band) facing
up, away from the board. Fold the cathode lead over the diode's body, so
it goes through the pad hole next to the body.
3. If it were my airplane, I would use the bottom of the box as a mounting base
and install the device without the top of the box attached. The large resistor
briefly dissipates substantial energy as heat when the supercapacitors are
charging, and the capacitors will live longer, happier lives if that heat isn't
dumped inside an enclosed space.
4. A blob of *neutral cure* RTV silicone or Shoe Goo around the base of the large
TO-220 resistor will promote long-term durability. Its leads support both
the resistor body and the heatsink, so in an environment subject to g-loads and
vibration, added mechanical support will relieve stress from the leads. [Do
*not* use standard "kitchen and bath" silicone on electronics; the vinegar smell
while it cures is acetic acid, a corrosive.]
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=475087#475087
Attachments:
http://forums.matronics.com//files/voltage_slump_eliminator_214.pdf
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