Today's Message Index:
----------------------
1. 04:44 AM - Re: Nav/Strobe lights (Roberto Giusti)
2. 06:17 AM - Re: Nav/Strobe lights (Shaun Simpkins)
3. 06:56 AM - Problem with Whelen Stobe - Help (Timothy Freeze)
4. 07:53 AM - Re: Nav/Strobe lights (John & Amy Eckel)
5. 08:38 AM - Re: Problem with Whelen Stobe - Help (Shannon Knoepflein)
6. 08:54 AM - Re: Problem with Whelen Stobe - Help (Michel Therrien)
7. 01:01 PM - Power budget (Treff, Arthur)
8. 02:22 PM - Re: Power budget (Matt Prather)
9. 02:54 PM - Re: Power budget (Phil Birkelbach)
10. 03:31 PM - Nav/Strobe lights (BAKEROCB@aol.com)
11. 05:28 PM - Re: Problem with Whelen Stobe - Help (Jerzy Krasinski)
12. 08:33 PM - Re: Power budget (Richard Sipp)
13. 09:38 PM - Fw: PM-OV and E-bus switch (David Carter)
Message 1
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| Subject: | Nav/Strobe lights |
--> AeroElectric-List message posted by: "Roberto Giusti" <roby@mail.com>
I contacted Nova and they said that I would get the absolute brightest
flash with their HPS4 power supply.
The spec sheet states 28.5 Joules primary flash and 12.5 joules
secondary flash in double flash mode.
In fact it is so powerful that it won't work with their standard heads.
They have special HPS heads (expensive and bulky), but on the phone they
said that whelen heads should cope with this supply.
So an option could be to use the Nova HPS4 power supply with Whelen
heads.
Roberto Giusti
RV8 QB Italy
roby@mail.com
Message 2
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| Subject: | Re: Nav/Strobe lights |
--> AeroElectric-List message posted by: "Shaun Simpkins" <shauns@hevanet.com>
I obsessed about this subject a while ago. This is one of those subjects
that a homebuilder's FAQ should address.
Aeroflash strobes are, by their own admission, not compliant with today's
strobe output requirements. Bob is right, it takes nearly 20 joules AND a
concentrating lens like the ones that Whelen makes to meet the current
FAA regs.
If you're wanting to see a copy of the FAA regs, you can look up the page
in your Aircraft Spruce catalog, or browse the Whelen website. If you want
more detail, the FAA's website has tons of articles on lighting regs, definitions,
and measurement methods.
So why can Aeroflash continue to sell their product? In the certified market,
to replace preexisting Aeroflash units. There are scads of Aeroflash strobes
in all those pre-1980 Cessnas out there, and most every manufacturer at one
time or another used Aeroflash.
In the experimental market, it's often the case that those aircraft are not flown
at night and the strobes are being bought for daytime visibility enhancement.
There's no regs for daytime use of strobes. Inspectors often don't concentrate
on strobe output when there are far more pressing safety issues to be judged.
But if you want to be absolutely legal for night flight, Whelen equivalent strobes
and
power supplies are necessary. You'll notice that Cirrus and Lancair
both use Whelen. Those with 28V systems in Europe can use Bosch as well...
Shaun Simpkins
Message 3
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| Subject: | Problem with Whelen Stobe - Help |
--> AeroElectric-List message posted by: "Timothy Freeze" <s35pilot@hotmail.com>
Hi,
I have the Whelen "a600" strobe and "hdacf" power supply on my cozy III. I
bought the supply early in the project and when I finally completed it the
supply had been sitting for 10 years!
I now have over 200 hours on the aircraft but when I first turn on the
strobe I can hear the charge and firing of the stobe. The noise goes away
after about 10 minutes. I thought perhaps the battery was not fully charged
or something like that so I put a trickle charger on the battery to see if
that cured it. Nope.
So I talked to the Whelen guy when I was at sun n fun and he said "The
supply was too old and needed work" & "It's out warrenty and the capacitors
were probably just old". He told me "It's cheaper to buy a new power
supply". I thanked him for his help and went in search of a replacment
supply. SHOCK AND AWE - well I priced it and it is $350 + shipping ...
ouch.
The whelen guy seemed kind of rude ... like he didn't really want to be at
the show listening to customers. I felt he just wanted me to go away, so I
didn't pester him. I just felt he wanted me to go away! He also didn't
inspire my confidence that he knew what he was talking about. Just a
feeling but I try to listen to them!
I really want to get this fixed - I'm tired of people telling me it sounds
like my ELT is going off when I key the mike after I first start off flying.
So I trun the stobe off and ask if they still hear it - nope. Then I tell
them I'm trying to fix it. I leave off the part about "I don't kanow how to
fix it". :-)
Since it is kind of a pain to remove the power supply (I have to take one
wing off as I put the supply in the strake), and possibly expensive, do you
think this is the problem or should I do more trouble shooting?
Can I just buy new capacitor(s) from Newark or Digikey and save a pile of
money? I know I can do the work as far as safely removing, discharging, and
replacing capacitors unless they are some weird electrical or physical
configuration and I can't get them commercially.
I've montored this list for a long time now. This is my first request for
help. I'd appreciate any shared thoughts, experience, or suggestions.
Thanks in advance.
Tim
Cozy N215TW
email at s35pilot@hotmail.com
Message 4
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| Subject: | Re: Nav/Strobe lights |
--> AeroElectric-List message posted by: John & Amy Eckel <eckel1@comcast.net>
----- Original Message -----
From: "Shaun Simpkins" <shauns@hevanet.com>
Subject: Re: AeroElectric-List: Nav/Strobe lights
> --> AeroElectric-List message posted by: "Shaun Simpkins"
<shauns@hevanet.com>
>
> I obsessed about this subject a while ago. This is one of those subjects
> that a homebuilder's FAQ should address.
>
> Aeroflash strobes are, by their own admission, not compliant with today's
> strobe output requirements. Bob is right, it takes nearly 20 joules AND a
> concentrating lens like the ones that Whelen makes to meet the current
> FAA regs.
>
> If you're wanting to see a copy of the FAA regs, you can look up the page
> in your Aircraft Spruce catalog, or browse the Whelen website. If you
want
> more detail, the FAA's website has tons of articles on lighting regs,
definitions,
> and measurement methods.
>
> So why can Aeroflash continue to sell their product? In the certified
market,
> to replace preexisting Aeroflash units. There are scads of Aeroflash
strobes
> in all those pre-1980 Cessnas out there, and most every manufacturer at
one
> time or another used Aeroflash.
> In the experimental market, it's often the case that those aircraft are
not flown
> at night and the strobes are being bought for daytime visibility
enhancement.
> There's no regs for daytime use of strobes. Inspectors often don't
concentrate
> on strobe output when there are far more pressing safety issues to be
judged.
>
> But if you want to be absolutely legal for night flight, Whelen equivalent
strobes and
> power supplies are necessary. You'll notice that Cirrus and Lancair
> both use Whelen. Those with 28V systems in Europe can use Bosch as
well...
>
> Shaun Simpkins
Shaun,
Thanks for clearing up this issue for me and doing the research.
I have often wondered about the legality of the Aeroflash strobes.
Thanks.
John, A230
>
>
Message 5
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| Subject: | Problem with Whelen Stobe - Help |
--> AeroElectric-List message posted by: "Shannon Knoepflein" <kycshann@kyol.net>
Maybe try calling Whelen and explaining the situation. If they think
its the power supply, tell them you'll buy a new power supply and change
it out, but if that doesn't fix it, you will expect a full refund. Or,
if you have a buddy that is building, just borrow his supply maybe and
try that out?
---
Shannon Knoepflein <---> kycshann@kyol.net
-----Original Message-----
From: owner-aeroelectric-list-server@matronics.com
[mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of
Timothy Freeze
Subject: AeroElectric-List: Problem with Whelen Stobe - Help
--> AeroElectric-List message posted by: "Timothy Freeze"
<s35pilot@hotmail.com>
Hi,
I have the Whelen "a600" strobe and "hdacf" power supply on my cozy III.
I
bought the supply early in the project and when I finally completed it
the
supply had been sitting for 10 years!
I now have over 200 hours on the aircraft but when I first turn on the
strobe I can hear the charge and firing of the stobe. The noise goes
away
after about 10 minutes. I thought perhaps the battery was not fully
charged
or something like that so I put a trickle charger on the battery to see
if
that cured it. Nope.
So I talked to the Whelen guy when I was at sun n fun and he said "The
supply was too old and needed work" & "It's out warrenty and the
capacitors
were probably just old". He told me "It's cheaper to buy a new power
supply". I thanked him for his help and went in search of a replacment
supply. SHOCK AND AWE - well I priced it and it is $350 + shipping ...
ouch.
The whelen guy seemed kind of rude ... like he didn't really want to be
at
the show listening to customers. I felt he just wanted me to go away,
so I
didn't pester him. I just felt he wanted me to go away! He also didn't
inspire my confidence that he knew what he was talking about. Just a
feeling but I try to listen to them!
I really want to get this fixed - I'm tired of people telling me it
sounds
like my ELT is going off when I key the mike after I first start off
flying.
So I trun the stobe off and ask if they still hear it - nope. Then I
tell
them I'm trying to fix it. I leave off the part about "I don't kanow how
to
fix it". :-)
Since it is kind of a pain to remove the power supply (I have to take
one
wing off as I put the supply in the strake), and possibly expensive, do
you
think this is the problem or should I do more trouble shooting?
Can I just buy new capacitor(s) from Newark or Digikey and save a pile
of
money? I know I can do the work as far as safely removing, discharging,
and
replacing capacitors unless they are some weird electrical or physical
configuration and I can't get them commercially.
I've montored this list for a long time now. This is my first request
for
help. I'd appreciate any shared thoughts, experience, or suggestions.
Thanks in advance.
Tim
Cozy N215TW
email at s35pilot@hotmail.com
Message 6
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| Subject: | Re: Problem with Whelen Stobe - Help |
--> AeroElectric-List message posted by: Michel Therrien <mtherr@yahoo.com>
In my installation manual, it's written:
"WARNING: Strobe light power supplies are meant to be
used, not to remain in an inactive state. Any strobe
light power supply that has been out of service for a
long period of time is subject to failure because the
electrolytic condenser loses its polarity formation.
A strobe light power supply not having been used for
one year or longer is vulnerable to failure."
And the more interesting part:
"If this is the case, it is recommended to start
operating the system on a voltage that is reduced by
25% for 10 to 15 minutes before putting the power
supply into normal service. This will preven t
overheating of the condenser while they reform. If
the power supply, after a long period of non use, is
operated at full voltage immediately, there is an
excellent possibiliyt that the condenser will become
overheated."
--- Timothy Freeze <s35pilot@hotmail.com> wrote:
> --> AeroElectric-List message posted by: "Timothy
> Freeze" <s35pilot@hotmail.com>
>
> Hi,
>
> I have the Whelen "a600" strobe and "hdacf" power
> supply on my cozy III. I
> bought the supply early in the project and when I
> finally completed it the
> supply had been sitting for 10 years!
>
http://search.yahoo.com
Message 7
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--> AeroElectric-List message posted by: "Treff, Arthur" <Arthur.Treff@Smartm.com>
'Letric Bob (and the list),
I'm putting together my power budget for my RV-8's electrical system. When I use
the max current draw shown on all the avionics specifications along with strobes,
landing and taxi lights and pitot heat, I'm up towards 60 amps! Clearly
I must be doing something wrong. Can you provide some guidance on how to size
an alternator and if there is a multiplier that is normally used to calculate
nominal current from the max that is published. It will be a basic IFR ship
with pitot heat and lights and Trutrack with alt hold.
For the GNS 430, for instance, Garmin tech support said that when the unit is just
receiving in cruise, expect 1.5 amps; during approach phase, when driving
needles and switching freq's and cursoring around, expect 3.0 amps. Then, when
the mic is keyed, ADD another 6 amps. This appears very high to me, as the
installation guide from Garmin specifies two inputs, each protected by a 5 amp
fuse.
With lighting, should I expect that the 100W landing light draws 8.3 amps at all
times, or is this an inrush current? Whelen strobe power supply says its rated
for 7 amps, is that the value I should put into my budget? I'm using a Piper
heated pitot/static mast, but have no clue how much it draws.
Most people I talk to say that a 40 amp alternator is more than most planes need.
Any comments on how to get me there?
Art Treff
RV-8
Message 8
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| Subject: | Re: Power budget |
--> AeroElectric-List message posted by: "Matt Prather" <mprather@spro.net>
Art,
Please
see my comments below.
> --> AeroElectric-List message posted by: "Treff, Arthur"
> <Arthur.Treff@Smartm.com>
>
> 'Letric Bob (and the list),
>
> I'm putting together my power budget for my RV-8's electrical system.
> When I use the max current draw shown on all the avionics specifications
> along with strobes, landing and taxi lights and pitot heat, I'm up
> towards 60 amps! Clearly I must be doing something wrong. Can you
> provide some guidance on how to size an alternator and if there is a
> multiplier that is normally used to calculate nominal current from the
> max that is published. It will be a basic IFR ship with pitot heat and
> lights and Trutrack with alt hold.
>
When doing a power budget, you are most interested in the average
consumption. The max usage only really comes into play when
deciding how big the wire and breaker need to be.
> For the GNS 430, for instance, Garmin tech support said that when the
> unit is just receiving in cruise, expect 1.5 amps; during approach
> phase, when driving needles and switching freq's and cursoring around,
> expect 3.0 amps. Then, when the mic is keyed, ADD another 6 amps. This
> appears very high to me, as the installation guide from Garmin specifies
> two inputs, each protected by a 5 amp fuse.
6 Amps seems high for continuous transmit, as that would be 72W burned,
and at 50% efficiency ( a reasonable assumption for a transmitter) you would
radiate 36W. I didn't think any GA radios are putting out that much. A 6A
transient might be appropriate for figuring breaker size to avoid nuisance
trips.
For com radios, transponder, flap/trim/gear motors the standby current
can be used for power budget. The duty cycle operated at max current
rating is very low.
>
> With lighting, should I expect that the 100W landing light draws 8.3
> amps at all times, or is this an inrush current? Whelen strobe power
> supply says its rated for 7 amps, is that the value I should put into my
> budget? I'm using a Piper heated pitot/static mast, but have no clue
> how much it draws.
For lighting, you need to budget the bulb's rated demand. A 100W bulb
uses at least 8.3A continuous, probably more if you consider that by the
time you get to 12V, your LV light is flashing. If your alternator is
keeping
its end up, you are probably driving 13V to the bulb.
Bob (and I believe others) has shown an analysis of strobe power use.
Basically, you can take the energy (in Joules) of each flash and multiply
that
by the number of flashes per unit time to get the average wattage
>
> Most people I talk to say that a 40 amp alternator is more than most
> planes need. Any comments on how to get me there?
>
If you do the analysis based on the duty cycle of each device I think it
will all work out okay. Its not a problem if on a momentary basis your
alternator doesn't keep up. I'll bet that in most cars if you are out
driving
during a summer evening rain storm with the AC/defr, wipers and headlights
and then lower a window while sitting at a traffic light, you will dip into
the reserves that the battery supplies.
> Art Treff
> RV-8
>
>
Regards,
Matt-
Message 9
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| Subject: | Re: Power budget |
--> AeroElectric-List message posted by: "Phil Birkelbach" <phil@petrasoft.net>
I am no expert but I have been doing my power budget lately as well. I used
only continuous load numbers for devices that will be on together at any
given time. I didn't count the flap motor, or the trim servos. I didn't
include the power used during transmitting on the comm either. It is only
going to be for a few seconds and the Alt will have a chance to catch up
once I let go of the mic.
Use the max numbers for sizing wire and the continuous numbers for
alternator sizing. The idea is to only include loads that will be on
together in the airplane. For instance. I will flash my landing lights
during almost all operations this measn that only one will be on at a time
so I only include one lamp in my continuous load power budget for enroute
flight. When I enter the pattern to land at night both lights come on full
time, but the autopilot is not part of this load because I turned it off.
Yes the flap motor pulls 3A but why include it since it runs for about 30
seconds per flight. The battery is good for loads upwards of 200A.
The GNS 430 numbers that you gave sound a little conservative but probably
okay to use. The pitot heat will pull about 8Amps for every 100Watts of
heat it makes. I looked at Gretz Aero and his are between 8 and 12 Amps.
The 100Watt lamps will use up a little over 8 Amps continuously. P=VI.
Power(Watts) = Voltage(Volts) x Current(Amps) (DC power only)
So worst case is landing at night with the Pitot Heat on. Positon lights
(6A) Two 100W Landing lights (16A) Strobes (7A) and Pitot Heat (10A) you are
at 39Amps. I would imagine that you need a 60Amp alternator.
Leave yourself some room for battery charging too. If you are right on the
ragged edge there'll be no juice left to charge the battery.
Godspeed,
Phil Birkelbach - Houston Texas
RV-7 N727WB (Reserved) - Fuselage
http://www.myrv7.com
----- Original Message -----
From: "Treff, Arthur" <Arthur.Treff@Smartm.com>
Subject: AeroElectric-List: Power budget
> --> AeroElectric-List message posted by: "Treff, Arthur"
<Arthur.Treff@Smartm.com>
>
> 'Letric Bob (and the list),
>
> I'm putting together my power budget for my RV-8's electrical system.
When I use the max current draw shown on all the avionics specifications
along with strobes, landing and taxi lights and pitot heat, I'm up towards
60 amps! Clearly I must be doing something wrong. Can you provide some
guidance on how to size an alternator and if there is a multiplier that is
normally used to calculate nominal current from the max that is published.
It will be a basic IFR ship with pitot heat and lights and Trutrack with alt
hold.
>
> For the GNS 430, for instance, Garmin tech support said that when the unit
is just receiving in cruise, expect 1.5 amps; during approach phase, when
driving needles and switching freq's and cursoring around, expect 3.0 amps.
Then, when the mic is keyed, ADD another 6 amps. This appears very high to
me, as the installation guide from Garmin specifies two inputs, each
protected by a 5 amp fuse.
>
> With lighting, should I expect that the 100W landing light draws 8.3 amps
at all times, or is this an inrush current? Whelen strobe power supply says
its rated for 7 amps, is that the value I should put into my budget? I'm
using a Piper heated pitot/static mast, but have no clue how much it draws.
>
> Most people I talk to say that a 40 amp alternator is more than most
planes need. Any comments on how to get me there?
>
> Art Treff
> RV-8
>
>
Message 10
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| Subject: | Nav/Strobe lights |
--> AeroElectric-List message posted by: BAKEROCB@aol.com
IAeroElectric-List message previously posted by: Rico Voss <vozzen@yahoo.com>
<< .....skip......My question is: Does the Airworthiness Cert. (Operating
LImitations?)
declare that the aircraft is equipped to fly at night, or does it say that
it can be flown at night IF it meets the lighting
requirements......skip.....--Richard >>
4/17/2003
Hello Richard, Here is an extract from my 4/13/2003 posting {...skip.... The
Operating Limitations for your specific aircraft should have some words in it
that read something like "After completion of Phase I flight testing, unless
appropriately equipped for night and/or instument flight in accordance with
91.205, this aircraft is to be operated under VFR, day only."
That means that once your aircraft is "appropriately equipped" and you have
the transponder, encoder, and altimeter inspections required for IFR
operations (and repeated every two years) you are good to go -- no "IFR
certification" regarding the avionics equipment installed is
involved**....skip.....}
So the same philosophy applies to the lighting required for night operations
-- the aircraft must be "appropriately equipped". In order to make that
determination one must dig into the FAR's and determine what is "appropriate"
in the eyes of the FAA. This subject has been written about before on the
list and you can search the archives as well as the FAR's to arrive at your
conclusion.
'OC' Baker, Builder of KIS TR-1 #116 4/14/97 - ?/?/?
Message 11
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| Subject: | Re: Problem with Whelen Stobe - Help |
--> AeroElectric-List message posted by: Jerzy Krasinski <krasinski@direcway.com>
Timothy Freeze wrote:
> "....when I first turn on the strobe I can hear the charge and firing of the
stobe. The noise goes away after about 10 minutes...."
>
It is not clear to me what are the symptoms. Strobe power supplies are
always a little noisy. You can always hear high frequency ton of the
high voltage converter, and you can always hear a quiet and periodic
thumps when the strobe fires. Is that what you hear? If that is the case
I do not see much wrong, the sound of the converter sometimes can get
louder if a part of the laminated iron core gets loose.
Or do you hear not periodic and quite loud sound reminding a small
hammer strike against a metal, which typically happens without a flash.
That is most likely a sound of the capacitor breaking down. The
capacitor sometimes can get cured as described in another email by
running the strobe for some time at reduced voltage.
Or perhaps you hear it through the electrical installation in your
headphones? And what happens after those 10 minutes? Is the strobe still
working or it quits?
Jerzy
Message 12
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| Subject: | Re: Power budget |
--> AeroElectric-List message posted by: "Richard Sipp" <rsipp@earthlink.net>
My RV-4 has the following electrical power consumers:
landing lights (big old GE bulbs)
nav lights
GPS/com
Nav/com
transponder
3 unit strobes
single cockpit flood led
cockpit lighting dimmer
VM1000 engine monitor
intercom
boost pump
When all of this is operating (not transmitting) the amp load on the VM1000
is stable at 27 amps.
I use a B&C 35 amp alternator. With the above load and 700 rpm the voltage
drops from the normal 14.3 to 13.9.
At any rpm above idle the voltage returns to 14.3. Normal day VFR cruise
load is about 15 amps.
Dick Sipp
RV4 N250DS
Message 13
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| Subject: | PM-OV and E-bus switch |
--> AeroElectric-List message posted by: "David Carter" <dcarter@datarecall.net>
Geof,
I missed the response to your e-mail below. If you got one from Bob, and if
you saved it, could you fwd it to me? Thanks. I've just studied the Z-
diagrams in Aeroelectric Connection and re-read several chapters - I'm
jumping in with both feet to become "an aircraft electrical systems designer
(homebuilt)".
I liked your 2nd question, about effect of having e-bus alternate feed
switch on at same time battery switch was on. If it is true that there is
"no effect", then there is a significant implication: The e-bus alternate
feed switch could be left "on" all the time, in anticipation of a serious
malfunction requiring killing the "battery switch and main bus". That would
reduce the pilot actions from 2 to 1 - "turn off battery switch". You'd
eliminate "then turn on essential bus alternate feed". (I was going to keep
this "private" but because this system is being discussed on the list, I'll
send it to the list, also.)
David Carter
----- Original Message -----
From: "Geoff Evans" <hellothaimassage@yahoo.com>
Subject: AeroElectric-List: PM-OV and E-bus switch
> --> AeroElectric-List message posted by: Geoff Evans
<hellothaimassage@yahoo.com>
>
> Bob. I sent this question to you via email, but perhaps it got lost by the
> wayside. I'll repeat the question here.
>
> I have a question about the B&C PM-OV 14 product.
>
> It looks like all the same stuff you recommed for protecting the SD-8
> alternator, except the relay has extra lugs on it for the light bulb. The
B&C
> website says that, if wired according to their diagram, that the light
will
> illuminate if the alternator switch is left off or if the crowbar trips.
>
> I think I understand how the circuit trips, but I don't understand why you
> would want a light that illuminates when the alternator is turned off...
> Assuming that I'm going to use the SD-8 as a backup alternator, and
following
> your advice about not putting two alternators on the same bus at the same
time,
> why would I want a light that functioned in this manner? The light would
be on
> for all normal operations.
>
> Perhaps this product is designed to be used with the SD-8 when it is the
only
> alternator in the airplane, or when it is running on a separate, isolated
> bus...
>
> ------
>
> On a totally different subject.. What happens in your Z-11 circuit
philosophy
> if the E-bus alternate feed switch is on at the same time the battery
master
> switch is on? It looks to me like absolutely nothing, but I just wanted to
make
> sure.
>
> Thanks.
> -Geoff
>
> RV-8 QB Fuselage
>
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