Today's Message Index:
----------------------
1. 09:36 AM - Re: Z-14 with dual Lightspeed III and SD-8 (Erich_Weaver@URSCorp.com)
2. 11:55 AM - Re: Re: Z-14 with dual Lightspeed III and SD-8 (RV Builder (Michael Sausen))
3. 12:52 PM - Re: Re: Z-14 with dual Lightspeed III and SD-8 (Matt Prather)
4. 01:44 PM - Re: Re: Z-14 with dual Lightspeed III and SD-8 (RV Builder (Michael Sausen))
5. 02:35 PM - Re: Re: Z-14 with dual Lightspeed III and SD-8 (Hinde, Frank George (Corvallis))
6. 02:53 PM - Re: Re: Z-14 with dual Lightspeed III and SD-8 (Robert L. Nuckolls, III)
7. 03:18 PM - Re: Re: Z-14 with dual Lightspeed III and SD-8 (Robert L. Nuckolls, III)
8. 04:51 PM - Re: Re: Z-14 with dual Lightspeed III and SD-8 (RV Builder (Michael Sausen))
9. 05:26 PM - Re: Z-14 with dual Lightspeed III and SD-8 (bcondrey)
10. 08:00 PM - Re: Re: Z-14 with dual Lightspeed III and SD-8 (Sam Hoskins)
11. 08:10 PM - Re: Re: Z-14 with dual Lightspeed III and SD-8 (Robert L. Nuckolls, III)
12. 08:53 PM - Dual Plasma III and Z-13/8..needing 2 x batteries and C/B's...?(Was Bob Nuckolls' Z-14 with Dual...) (Rob du Plooy)
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
I dont think I am fully understanding this discussion. Bob, perhaps you
could provide a simple summary of the issue and concerns here for the l
ess
enlightened? There are a lot of folks out here with single or dual
lightspeed ignitions. Under what circumstances are they at risk? Any
suggested course of action? A lot of concern seems to have been expres
sed
without much direct input from the manufacturer.
erich
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
Thanks Bob for uncovering this. I had the same basic plan as you, using
a fuse off each of the two main batteries running up each side of the fusel
age to the two LSEIII's.
I think knowing this now I will use a slightly larger fuse off the batter
y, say 15amp with the appropriate wire of course, and then use breaker swit
ches for the LSE's. My batteries are in the back and I certainly don't wan
t two separate, unprotected wires running up the length of the fuselage. I
f it's an OV and not enough to blow the 15amp fuses then I can reset the LS
E's using the switch breakers. If it's something else that blows the 15amp
, probably won't make a difference at that point as it's either a fried com
ponent or a shorted wire. Does this sound like a workable solution to ever
yone?
Michael
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
I suspect such series protection will always blow the fuse and not the
breaker - if they both have the same rating. The time constant for
blowing most standard breakers is much slower than for fuses. You might
be able to upsize the wiring and fuse and get something to work - by
operating the fuse at a much smaller percentage of it's fault current
rating than the breaker. You could also pick a device with a slower blow
time than a normal ATC fuse. An MDL maybe?
The behavior of the system might also depend on how "good" the short is
that is presented by the LSE's internal crow bar. The peak current
wouldn't likely be anywhere close to that of connecting copper straight
across the battery terminals. The impedance of the crowbar comes into
play.
One question I can't remember being asked/answered is what voltage the
LSE's crowbar is designed to trip at. I suspect it might be quite high as
I think the systems are allowed to be run from a 24(28)V bus - the manual
lists proper operation up to 35V. When using an LSE on an airplane with a
12(14)V buss, the alternator's OV crowbar might be depended on to trip
sooner than the LSE crowbar.
Regards,
Matt-
> Thanks Bob for uncovering this. I had the same basic plan as you, using
> a fuse off each of the two main batteries running up each side of the
> fuselage to the two LSEIII's.
>
> I think knowing this now I will use a slightly larger fuse off the
> battery, say 15amp with the appropriate wire of course, and then use
> breaker switches for the LSE's. My batteries are in the back and I
> certainly don't want two separate, unprotected wires running up the
> length of the fuselage. If it's an OV and not enough to blow the 15amp
> fuses then I can reset the LSE's using the switch breakers. If it's
> something else that blows the 15amp, probably won't make a difference at
> that point as it's either a fried component or a shorted wire. Does
> this sound like a workable solution to everyone?
>
> Michael
>
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
Like I said, slightly larger fuse. :) Normal operation lists an LSEIII at 7.5AMP
requirement with a 10Amp fuse. My reasoning is that doubling the initial
fuse would allow the breaker to go first under normal circumstances. I do agree
that a slo-blo type fuse would probably decrease the likeliness of the fuse
blowing first.
I would just assume deal with this back at the batteries but it's not practical
to have the CB's back there with no easy way to reset when I'm flying alone
troubleshooting an overly quiet engine. I could feed one LSE from the main bus
and the second directly from a battery which would probably cover most circumstances.
Michael
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Matt Prather
Sent: Tuesday, February 03, 2009 2:50 PM
Subject: RE: AeroElectric-List: Re: Z-14 with dual Lightspeed III and SD-8
I suspect such series protection will always blow the fuse and not the
breaker - if they both have the same rating. The time constant for
blowing most standard breakers is much slower than for fuses. You might
be able to upsize the wiring and fuse and get something to work - by
operating the fuse at a much smaller percentage of it's fault current
rating than the breaker. You could also pick a device with a slower blow
time than a normal ATC fuse. An MDL maybe?
The behavior of the system might also depend on how "good" the short is
that is presented by the LSE's internal crow bar. The peak current
wouldn't likely be anywhere close to that of connecting copper straight
across the battery terminals. The impedance of the crowbar comes into
play.
One question I can't remember being asked/answered is what voltage the
LSE's crowbar is designed to trip at. I suspect it might be quite high as
I think the systems are allowed to be run from a 24(28)V bus - the manual
lists proper operation up to 35V. When using an LSE on an airplane with a
12(14)V buss, the alternator's OV crowbar might be depended on to trip
sooner than the LSE crowbar.
Regards,
Matt-
> Thanks Bob for uncovering this. I had the same basic plan as you, using
> a fuse off each of the two main batteries running up each side of the
> fuselage to the two LSEIII's.
>
> I think knowing this now I will use a slightly larger fuse off the
> battery, say 15amp with the appropriate wire of course, and then use
> breaker switches for the LSE's. My batteries are in the back and I
> certainly don't want two separate, unprotected wires running up the
> length of the fuselage. If it's an OV and not enough to blow the 15amp
> fuses then I can reset the LSE's using the switch breakers. If it's
> something else that blows the 15amp, probably won't make a difference at
> that point as it's either a fried component or a shorted wire. Does
> this sound like a workable solution to everyone?
>
> Michael
>
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
Absolutely..Then ditch the mechanical fuel pump and put the electric pumps in the
wingrrots.
You now have a vapour lock proof fuel system that will run on just about anything,
including ethanol.
Slightly off topic but you'd be amazed at how many builders balk at two electric
fuel pumps, but two EI's is perfectly acceptable.
Frank
RV7a..IFR All electric, fuel pumps included.
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of RV Builder (Michael Sausen)
Sent: Tuesday, February 03, 2009 1:42 PM
Subject: RE: AeroElectric-List: Re: Z-14 with dual Lightspeed III and SD-8
--> <rvbuilder@sausen.net>
Like I said, slightly larger fuse. :) Normal operation lists an LSEIII at 7.5AMP
requirement with a 10Amp fuse. My reasoning is that doubling the initial
fuse would allow the breaker to go first under normal circumstances. I do agree
that a slo-blo type fuse would probably decrease the likeliness of the fuse
blowing first.
I would just assume deal with this back at the batteries but it's not practical
to have the CB's back there with no easy way to reset when I'm flying alone
troubleshooting an overly quiet engine. I could feed one LSE from the main bus
and the second directly from a battery which would probably cover most circumstances.
Michael
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
At 11:26 AM 2/3/2009, you wrote:
>I dont think I am fully understanding this discussion. Bob, perhaps
>you could provide a simple summary of the issue and concerns here
>for the less enlightened? There are a lot of folks out here with
>single or dual lightspeed ignitions. Under what circumstances are they at risk?
The roots of this discussion go back a lot of years
and is not limited to any particular manufacturer's
design goals. Let me see if I can give you a distilled
down synopsis that moves toward focus on the specifics
of Lightspeed ignition systems.
History: Conventional wisdom for design and
fabrication of electrical systems suggests we
provide ship's accessories with power constrained
within the boundaries cited numerous documents
but they're all about the same. For our purposes,
let's talk about Mil-Std-704. For details, use the
search engine on my website and look for hits on
"mil-std-704". A similar search term on the
Matronics archives search engine will yield another
discussion and data-set. In particular, you can
get your own copy of this document at:
http://www.aeroelectric.com/Reference_Docs/Mil-Specs/Mil-Std-704f.pdf
On the accessory side, there's an equally large
library of documents that speak to design goals for
accessories. The TC aircraft industry is fond of
RTCA DO-160. I can't post a copy of this document
as the folks at RTCA are pretty protective of their
work product. Again, use the search engine on my
website and the Matronics archives to look up
"DO-160". You can access an outline of the spirit
and intent of DO-160 at:
http://www.aeroelectric.com/articles/DO-160.pdf
Irrespective of any words you read where the writer
brushes off the simple-ideas offered in these
documents, they have a long and rich history of
successful product design, development and operation
in both military and civilian certified aviation.
I've made a good living by bench-marking my work-
product and that of my associates against the design
goals suggested therein.
I've been guilty of plenty of screw-ups in 40+ years
that have cost my employer some dollars and some
customers some inconvenience. But mistakes of
attention or understanding were never attributable
to inadequacies of 160/704 used in concert to
craft robust and reliable systems. This is why
I've offered up these two documents as THE
STARTING PLACE for every new design.
OBAM aviation is blessed with the opportunity
to develop and exploit a constellation of new
ideas and products that promise to reduce weight,
cost, complexity with increases in performance
and safety. Best yet, these ideas can come into
the marketplace unburdened by the regulatory,
policy and procedural albatrosses that are dragging
once great companies down into the tar-pits of
economic and intellectual paralysis.
Since my first visit to OSH in '86, I've been aware
of dozens of exciting and useful ideas that
should be explored and perhaps exploited in OBAM aviation.
While listening to some starry-eyed entrepreneur's
excited explanation of an idea, I was acutely aware
of a lack of foundation in system integration basics.
From that very first year, I've offered my services
to any and all takers to help them craft input,
output and power connections that will improve
upon seamless integration with the rest of the airplane's
accessories.
To date, perhaps a half dozen folks have seen
fit to take advantage of this offer. Only
one required enough of my attention to justify billing
them. I made this same offer to Klaus (and his
competition!) on several occasions. I reminded them
all that I'm aware of the intellectual property
secrets of dozens of clients who do not perceive
risks for having used my services. Nonetheless,
for whatever reasons, very few folks have availed
themselves of my offer.
Current Events: Now comes a new revelation to the
community that a popular product is fitted with crowbar
ov protection. This raises a question as to
perceived value for adding such a feature internal
to a system accessory. NORMALLY . . . one designs
an accessory assuming that the prospective customer/
system integrator is aware of and complies with
the spirit and intent of 160/704. Further, given that
engine operations depend on the function of at least
one of two installed systems, what are the design goals
that prevent BOTH systems from responding to the same
OV event and shutting themselves down?
Why would a designer believe that adding this feature
adds value/safety to their product? Could it be a lack
of faith in the customer/integrator's ability to comply
with 160/704? This is a legitimate concern. My seminars
are sprinkled liberally with folks who's professional
skills have not trained them to think about these ideas.
We can only guess at the thoughts and motivation for
the case before us.
The questions to be explored:
(1) If the crowbar OV protection were left out, what
is the product's ability to stand off Mil-Std-704 compliant
transients.
(2) If so, would it not be BETTER to tell the customer
that their airplane's power generation system should
be crafted to stay at or below those limits? If you
buy a radio from King, Garmin, etc., this goes without
asking or answering.
(3) If not so, what if anything should be considered
to make the product more robust? This is usually very
easy. Power conditioning compliance taxes only a tiny
portion of the total design and qualification time
for clean-piece-of-paper designs.
(4) Finally, if the product under discussion is
not accompanied with detailed explanations of all
features that influence in-flight operations, why
not? The customer/system-integrator is severely
limited in crafting a best-we-know-how-to-do
system if there are hidden or inadequately described
features that affect performance. Even worse, overlooked
or hidden features could become root cause in a hazardous
scenario. This is why we do FMEA studies in groups with
a goal of leaving no failure mode unconsidered.
Path Forward: I will suggest that customers of the
Lightspeed systems invite Klaus to join the AeroElectric-
List for the purpose of sharing and sifting the
constellation of simple-ideas from which we can craft
the optimum solution.
> Any suggested course of action? A lot of concern seems to have
> been expressed without much direct input from the manufacturer.
Exactly. I'll make the List members aware that not all
of my past contacts with Klaus have been without
tension. This is why I'll suggest that any participation
by yours truly be carried out in this open forum. Klaus
may choose not to participate here. It's important that
he believe this is not a Star-Chamber being set up to abuse
him. But if there's any forum that offers the highest
probability of achieving understanding and crafting a
successful solution . . . it's right here.
As a first contribution to the solution I will assert
that crafting a 704-compliant power source is NOT
difficult.
Bob . . .
Message 7
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
At 03:41 PM 2/3/2009, you wrote:
>Sausen)" <rvbuilder@sausen.net>
>
> Like I said, slightly larger fuse. :) Normal operation lists an
> LSEIII at 7.5AMP requirement with a 10Amp fuse. My reasoning is
> that doubling the initial fuse would allow the breaker to go first
> under normal circumstances. I do agree that a slo-blo type fuse
> would probably decrease the likeliness of the fuse blowing first.
The fuse would need to be a LOT bigger. Crow-baring
a 5A breaker would open a 20-30A up-stream fuse.
This is because the I(square)*R time constant for
opening a breaker is MUCH larger than for fuses
of the same size. You can easily do this experiment
for your self. Go out to your car's battery and hook
an in-line fuse holder in series with a 5A breaker.
Put about 5 feet of 20AWG wire in the loop too to
limit max current.
Connect this combination across your car battery
and see how large the fuse has to be to stay closed
while the breaker trips. This is why we have fusible
links upstream of crowbar ov protection breakers in
all the Z-figures.
> I would just assume deal with this back at the batteries but it's
> not practical to have the CB's back there with no easy way to reset
> when I'm flying alone troubleshooting an overly quiet engine. I
> could feed one LSE from the main bus and the second directly from a
> battery which would probably cover most circumstances.
The big band-aid is to install a separate high
current relay to the battery through a LARGE
in line fuse . . . probably 30A. Run 14AWG wire
from the relay up to the panel mounted 5A breaker.
Continue on with what-ever wire is called out
to continue on to the ignition system. Now you
need switches to control right and left ignition
system relays at the battery. See:
http://aeroelectric.com/Pictures/Schematics/Battery_Feed_for_Ignition.pdf
This approach could be blessed in a TC aircraft
as providing circuit protection commensurate with
wire sizes AND making the system max-cold when
the switches are OFF.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
Message 8
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
Hmm, not a big fan of replacing one failure mode with another. I see a relay
as being a bit of a step back and probably more likely to fail than to see an
OV event. Maybe something as simple as using a 15amp breaker instead of a fuse
would be less complex and eliminate the problem of a fuse blowing faster than
a breaker, albeit more expensive.
Michael
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Robert L. Nuckolls, III
Sent: Tuesday, February 03, 2009 5:16 PM
Subject: RE: AeroElectric-List: Re: Z-14 with dual Lightspeed III and SD-8
At 03:41 PM 2/3/2009, you wrote:
>Sausen)" <rvbuilder@sausen.net>
>
> Like I said, slightly larger fuse. :) Normal operation lists an
> LSEIII at 7.5AMP requirement with a 10Amp fuse. My reasoning is
> that doubling the initial fuse would allow the breaker to go first
> under normal circumstances. I do agree that a slo-blo type fuse
> would probably decrease the likeliness of the fuse blowing first.
The fuse would need to be a LOT bigger. Crow-baring
a 5A breaker would open a 20-30A up-stream fuse.
This is because the I(square)*R time constant for
opening a breaker is MUCH larger than for fuses
of the same size. You can easily do this experiment
for your self. Go out to your car's battery and hook
an in-line fuse holder in series with a 5A breaker.
Put about 5 feet of 20AWG wire in the loop too to
limit max current.
Connect this combination across your car battery
and see how large the fuse has to be to stay closed
while the breaker trips. This is why we have fusible
links upstream of crowbar ov protection breakers in
all the Z-figures.
> I would just assume deal with this back at the batteries but it's
> not practical to have the CB's back there with no easy way to reset
> when I'm flying alone troubleshooting an overly quiet engine. I
> could feed one LSE from the main bus and the second directly from a
> battery which would probably cover most circumstances.
The big band-aid is to install a separate high
current relay to the battery through a LARGE
in line fuse . . . probably 30A. Run 14AWG wire
from the relay up to the panel mounted 5A breaker.
Continue on with what-ever wire is called out
to continue on to the ignition system. Now you
need switches to control right and left ignition
system relays at the battery. See:
http://aeroelectric.com/Pictures/Schematics/Battery_Feed_for_Ignition.pdf
This approach could be blessed in a TC aircraft
as providing circuit protection commensurate with
wire sizes AND making the system max-cold when
the switches are OFF.
Bob . . .
----------------------------------------)
( . . . a long habit of not thinking )
( a thing wrong, gives it a superficial )
( appearance of being right . . . )
( )
( -Thomas Paine 1776- )
----------------------------------------
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
I actually don't have an issue with this behavior (crowbar design) as long as it's
a published design feature. Lacking that, there's nothing providing any clues
to somebody installing these units that use of a CB vs a fuse should be considered
mandatory.
Text from the LSE Plasma III install instructions section 2.6:
When connecting the power supply, route the positive lead to a 5A pull-able circuit
breaker and then to the battery plus terminal, bypassing any electrical
buss or master solenoid. Refer to the Input Connector Diagram.
At this point not having specifics about voltage level, duration, etc. that causes
a crowbar event within the ignition is really just academic curiosity to me.
Real point is that there is apparently a crowbar circuit internal to the units
that is meant to trip a CB if overvoltage is detected (maybe also overtemp?)
and using an inaccessible fuse instead of a CB is just flat unacceptable (to
me). I haven't grounded the plane simply because I've got redundancy with
a 12 volt Z-14 implementation with B&C alternators and regulators. Not sure if
the regulators are faster than the Plasma III, but since the Plasma III will
accept 28 volt power I suspect the 12 volt regulator would trip an offending
alternator offline before the Plasma III crowbarred. Even if something went really
wrong with an alternator/regulator and an ignition popped the fuse, I've
still got a second, isolated system. I will however be reconfiguring the ignition
power supply wiring in the next couple of months.
I hope nobody interprets me being sour on LSE, I actually love the ignitions!
Klaus can be a little difficult to deal with and I can also accept that. My purpose
was simply to inform of a failure mode. Given that there are a lot of
LSE ignitions in the field and a lot of those are being powered through, this
can't be that big of a problem - except for the poor soul that has an overvoltage
condition which then causes the big fan up front to stop.
Bob
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=228385#228385
Message 10
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
I seem to remember that a CB was used, so you could easily disconnect the
power from the always hot bus, for example, when performing maintenance.
I once had a conversation with Klaus about some problems I was having durin
g
installation and told him I took power off a bus. He was adamant that I
follow the installation instructions and take power directly off the
battery. It ultimately turned that my problem was caused by too much
clearance between the Hall sensor and the rotating magnets.
Sam
www.samhoskins.blogspot.com
On Tue, Feb 3, 2009 at 7:24 PM, bcondrey <bob.condrey@baesystems.com> wrote
:
> bob.condrey@baesystems.com>
>
> I actually don't have an issue with this behavior (crowbar design) as lon
g
> as it's a published design feature. Lacking that, there's nothing provid
ing
> any clues to somebody installing these units that use of a CB vs a fuse
> should be considered mandatory.
>
> Text from the LSE Plasma III install instructions section 2.6:
> - When connecting the power supply, route the positive lead to a
5A
> pull-able circuit breaker and then to the battery plus terminal, bypassin
g
> any electrical buss or master solenoid. Refer to the Input Connector
> Diagram.
>
> At this point not having specifics about voltage level, duration, etc. th
at
> causes a crowbar event within the ignition is really just academic curios
ity
> to me. Real point is that there is apparently a crowbar circuit internal
to
> the units that is meant to trip a CB if overvoltage is detected (maybe al
so
> overtemp?) and using an inaccessible fuse instead of a CB is just flat
> unacceptable (to me). I haven't grounded the plane simply because I've g
ot
> redundancy with a 12 volt Z-14 implementation with B&C alternators and
> regulators. Not sure if the regulators are faster than the Plasma III, b
ut
> since the Plasma III will accept 28 volt power I suspect the 12 volt
> regulator would trip an offending alternator offline before the Plasma II
I
> crowbarred. Even if something went really wrong with an
> alternator/regulator and an ignition popped the fuse, I've still got a
> second, isolated system. I will however be reconfiguring the ignition po
wer
> supply wiring in the next couple of mont!
> hs.
>
> I hope nobody interprets me being sour on LSE, I actually love the
> ignitions! Klaus can be a little difficult to deal with and I can also
> accept that. My purpose was simply to inform of a failure mode. Given t
hat
> there are a lot of LSE ignitions in the field and a lot of those are bein
g
> powered through, this can't be that big of a problem - except for the poo
r
> soul that has an overvoltage condition which then causes the big fan up
> front to stop.
>
> Bob
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=228385#228385
>
>
===========
===========
===========
===========
>
>
Message 11
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Subject: | Re: Z-14 with dual Lightspeed III and SD-8 |
At 06:49 PM 2/3/2009, you wrote:
>Sausen)" <rvbuilder@sausen.net>
>
> Hmm, not a big fan of replacing one failure mode with another. I
> see a relay as being a bit of a step back and probably more likely
> to fail than to see an OV event. Maybe something as simple as
> using a 15amp breaker instead of a fuse would be less complex and
> eliminate the problem of a fuse blowing faster than a breaker,
> albeit more expensive.
>
>Michael
The relay is only to observe the TC world
convention for making wiring max-cold with
the switches off. Given that the breaker
requirement forces you to have a "bus" at
the panel, then the feeder to that bus must
be considerably "stiffer" than the energies
required to trip the breaker. Without the relay
the wire between battery and breaker is
not crash-worthy by certified standards.
If you wish to adopt other standards . . .
You are exceedingly unlikely to experience
a relay failure concurrent with any other
failure on a single tank of fuel. Further,
failure of one relay is backed up by the
second system. I.e., risks of double
ignition failure versus risk of an ov
condition is much lower.
Bob . . .
Message 12
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Subject: | Dual Plasma III and Z-13/8..needing 2 x batteries |
and C/B's...?(Was Bob Nuckolls' Z-14 with Dual...)
Hoo-boy....
Thanks Bob and others for recommending Z13/8....happy to continue with
your dwgs and single battery..... till I read about the Lightspeed
manual stating at paragraph ..2.7..
Electrical System Requirements
All Plasma CDI systems can be used with 12 or 24 volt electrical
systems. Input voltages above 35 volts or reversed polarity will cause
system damage.
For this reason it is mandatory that all aircraft using Plasma CD
Ignitions are equipped with over-voltage protection in their alternator
charging system(s). Over-voltage is a requirement for certified
aircraft. Power connection must be directly to the battery terminals to
avoid voltage spikes and electrical noise. Aluminum should never be
used as an electrical conductor for the Plasma CDI. Use only the
supplied aircraft quality stranded wire.
Electrical Operating Instructions
Dual Systems only: If you have installed an aux battery per the LSE
supplied drawing, monitor your voltmeter and do not switch to the aux
battery until the supply voltage of the main battery is below 6.5 Volts
or the engine is not running smoothly. After switching to the aux
battery, your voltmeter will read the voltage remaining in your aux
battery.
Do not switch your main alternator breaker in flight to avoid
potentially damaging voltage spikes. This does not apply to the
alternator field breaker.
And further at para.2.8A....
A. Power Supply -
=B7 When connecting the power supply, route the positive lead to
a pull-able breaker, 4-cyl systems use 5A ...., and then directly to the
battery plus terminal, bypassing any electrical buss or master solenoid.
Refer to the Input Connector Diagram & the Electrical Requirements
section 2.7.
See here.....
http://www.lightspeedengineering.com/Manuals/CdiManual_PlasmaII_II+_III.h
tm
And then for Dual Plasma CDI, Klaus further recommends.....
For Dual PLASMA CDI Installations, an auxiliary battery and dual
ignition indicator lights are recommended. Please click here for an
aux battery wiring diagram.
See Figure 4 for the dual ignition indicator lights diagram: click here.
See here for the AUX Batt
Diagram..........http://www.lightspeedengineering.com/Manuals/PS_Diagram.
htm
How do I incorporate these- the 2 x "pullable" C/bs and 2 x batteries -
within Z13/8...?
Thanks,
Robert
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