Today's Message Index:
----------------------
1. 07:06 AM - Re: BnC Continuous Duty Contactor 12 v (Eric M. Jones)
2. 08:37 AM - FYI: Powergate (Eric M. Jones)
3. 09:37 AM - Re: Re: BnC Continuous Duty Contactor 12 v (Robert L. Nuckolls, III)
4. 09:51 AM - Acceleration ratings for contactors (Robert L. Nuckolls, III)
5. 01:36 PM - Headset components (Richard Girard)
6. 03:29 PM - Re: Headset components (sttwig@wabroadband.com)
7. 05:27 PM - Re: Headset components (Richard Girard)
8. 06:15 PM - Re: AT150 Interrogation Light (Fox5flyer)
9. 07:17 PM - Re: Re: AT150 Interrogation Light (Robert L. Nuckolls, III)
10. 10:43 PM - Re: Re: Z-19/RB Question (Ed Holyoke)
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| Subject: | Re: BnC Continuous Duty Contactor 12 v |
Bob,
I would use a Type 70 for a puddle jumper of no particular consequence. I agree
that they have been used for decades. They are not competitive anymore. I aim
for designs where "carrying a spare" is not a requirement for a part, where
"better" can be had for not much money. "Better" in my world is defined as "greater
capability, wider specs, longer life, higher reliability...etc." Maybe even
"similar specs, lighter weight...." Not all builders care about this.
>Problems--
>1) Low Temperature rating. Only 122F max. You could land at Furnace >Creek in
Death Valley in May and take off in October. Maybe. This is >primarily due to
the Nylon innards. This is a drop-dead reason to avoid >the part.
>2) Not sealed. Not dust proof, or fuel proof.
> Neither are most of the switches, contactors, even
> alternators that have been used with great success
> for decades.
Bob, that's partially true, but Kilovacs and Gigavacs can shut off your battery
whilst saturated in fuel. They can also shut off a runaway alternator. They
will last forever. They cost more. They have lower hold currents. They use bidirectional
Zeners for coil suppression. Nice, huh?
>3) Low interrupt capacity.
> But they're never asked to interrupt anything but normal
> pre-parking currents in aircraft . . . maybe 10A? For a
> time, the TC aircraft industry attempted to use the
> intermittent duty versions of these contactors for starter
> control service and found them unsatisfactory.
You are referring to a specific application. I referring to general applications.
> However, they have proven a good value (I didn't say lasts
> forever) in light aircraft battery contactor service.
> In other words, the 8x more expensive 6041H series mil
> spec contactors did not last even 4x as long. Given the
> exceedingly light duty cycles expected from these devices
> the way we use them (in failure tolerant systems) they
> are of good value.
I don't disagree. They are a good value. But Omron contactors (50A) http://tiny.cc/sXDp3 are a 3X better value and are tiny in comparison. The Type 70 is long in the tooth. As you recall this latest brushfire was sparked by troublemaker Jeff Skiba poking around to get information on higher current performance. He started this....
>4) High hold current---16 ohm coil. Almost one amp.
> Which is not an issue as long as the alternator
> is running . . . you have power to burn. When the
> alternator is not running, this device is turned
> off for endurance mode operations.
An ampere here, and ampere there...pretty soon you have real power waste. Our philosophies
differ. I remember in 1960 when you could buy surplus aircraft and
they'd come with full fuel tanks. Not anymore.
>5) Low hold force. The specifications call for specific orientation.
>2G rating?
> I've tested these at over 12g. Where do you find any recommendations with respect
to g-loading. I can tell you that the vertical orientation is to reduce potential
for moisture ingress due to condensation and/or splash . . . as you've
noted, they are not sealed. As a battery contactor, they are closed in all phases
of flight and exceedingly difficult to
> force open with g-loads.
You could be right on this. Type 70 specs are impossible to get on this, (and believe
me I've tried). I interpret the orientation spec to be a g-load concern.
But Kilovac and Gigavac and others always spec g-load. Usually 10g's.
>6) Wildly wrong for B&C to use coil suppression diodes on these. This
>causes short lifetimes on the B&C parts.
> I've also demonstrated that this is not true.
As I said Bob, you are wonderfully on-the-mark about thousands of things, and only
wildly wrong about only a few.
One Hundred Dollars U.S. to your favorite charity and a jar of jalapenos to you
if an agreed upon third party will test the type-70 contactor using 1N5401 Diodes
vs. 18V SnapJacks for coil suppression in an agreed upon test. My winning
requires you to never again espouse this bonehead notion.
>7) Not designed to open against voltages above 36 volts. (So forget the
>B-lead applications)
>
> True . . . and not recommended to routinely SWITCH such
> loads but will be just fine as suggested on the third page
> of:
>
> http://aeroelectric.com/articles/Adapting_IR_Alternators_to_Aircraft.pdf
>
> where we will routinely switch the alternator ON and OFF at will
> without exceeding the contactors rated operating conditions.
>There are better ways to go. Omron's line of automotive contactors
> (CHEAP) and Kilovac's EV200 series, Blue Sea 9012, Gigavac's GX-11. >Expensive
but preferred.
> Preference is another matter entirely . . . and when
> it comes to preferences, I'll concede to anyone's desires.
> I've even cited alternatives that include the Kilovac
> EV200. But let us not resort to generating climates of fear
> on the part of the neophyte airplane builders. The track
> record on this part for return on investment has been exemplary.
>Better yet, avoid all contactors and use manual switches if you can.
> This IS a stretch Eric. It's true that contactors are the
> most highly stressed devices on an airplane after generators
> and followed by alternators. It's also true that they are
> a significant maintenance item on EVERY airplane from the
> C-150 through the Hawkers. But so are tires, batteries,
> generators, etc. The artfully crafted system tolerates
> these service life limitations without placing the aircraft
> or occupants at risk. Can we really recommend that anyone
> resort to manually operated high current switches (bring
> high current conductors within reach of pilot) just to avoid
> a service-life issue on a 100-our a year airplane?
Bob, Stretching is a good, but not necessary thing. I recommend to my builder-friends
using a Flaming River racecar battery switch to satisfy the FAA for the
one-hand battery disconnect. That's what's going into my Glastar. No contactor
needed. Most other contactors can go bye-bye too.
"Everything you've learned in school as 'obvious' becomes less and less obvious
as you begin to study the universe. For example, there are no solids in the universe.
There's not even a suggestion of a solid. There are no absolute continuums.
There are no surfaces. There are no straight lines."
-R. Buckminster Fuller
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones@charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=195736#195736
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See: http://www.perfectswitch.com/downloads/relaybrochure.pdf
This guy sells big SSRs. I'd like to see a schematic. But it might be worth looking
into. My concern is that he might have miscalculated the dissipation, but
I can't tell from the information.
Anybody want to investigate and report back?
--------
Eric M. Jones
www.PerihelionDesign.com
113 Brentwood Drive
Southbridge, MA 01550
(508) 764-2072
emjones@charter.net
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=195744#195744
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| Subject: | Re: BnC Continuous Duty Contactor 12 v |
At 07:00 AM 7/30/2008 -0700, you wrote:
>
>Bob,
>
>I would use a Type 70 for a puddle jumper of no particular consequence. I
>agree that they have been used for decades. They are not competitive
>anymore. I aim for designs where "carrying a spare" is not a requirement
>for a part, where "better" can be had for not much money. "Better" in my
>world is defined as "greater capability, wider specs, longer life, higher
>reliability...etc." Maybe even "similar specs, lighter weight...." Not all
>builders care about this.
Don't now how to quantify "competitive". Hundreds
of thousands of airplanes have flown with this contactor
and I doubt that few if any owners felt compelled to
"carry a spare". Yes, I CAN select from a variety of
products with "better" specs . . . but in the final
analysis, how does this affect John Q Pilot's utility
realized from his airplane? I'm aware of NO contactors
suited for battery service that are smaller, noise free,
and deliver better life for the dollars spent. You've
stirred a lot of un-quantified superlatives into this
stew.
> > Neither are most of the switches, contactors, even
> > alternators that have been used with great success
> > for decades.
>
>
>Bob, that's partially true, but Kilovacs and Gigavacs can shut off your
>battery whilst saturated in fuel. They can also shut off a runaway
>alternator. They will last forever. They cost more. They have lower hold
>currents. They use bidirectional Zeners for coil suppression. Nice, huh?
Sure . . . but how many battery contactors have ever been
asked to open the battery while fuel-soaked? The hold current
electronics duty cycle switches the coil circuit and proved
to be a noise issue in at least one instance. I was hoping
to get one into the lab to look at DO-160 conducted and
see how much filter was needed to quiet the puppy down.
If I were searching for stretched convictions, I might
offer that the electronics in the EV200 were vulnerable
to lightning strike.
> >3) Low interrupt capacity.
>
>
> > But they're never asked to interrupt anything but normal
> > pre-parking currents in aircraft . . . maybe 10A? For a
> > time, the TC aircraft industry attempted to use the
> > intermittent duty versions of these contactors for starter
> > control service and found them unsatisfactory.
>
>
>You are referring to a specific application. I referring to general
>applications.
The man was asking about a battery contactor. I was
addressing that question. I added a note that
the manner in which a b-lead contactor would be used
in a proposed alternator controller, the type 70
would be suited for that task too. The ONLY places where
the venerable type 70 has been recommended for
consideration in a Z-figure are situations where
it is not required to SWITCH a heavy load, only
CARRY them. Starter contactors are another application
that demands special consideration.
> > However, they have proven a good value (I didn't say lasts
> > forever) in light aircraft battery contactor service.
> > In other words, the 8x more expensive 6041H series mil
> > spec contactors did not last even 4x as long. Given the
> > exceedingly light duty cycles expected from these devices
> > the way we use them (in failure tolerant systems) they
> > are of good value.
>
>
>I don't disagree. They are a good value. But Omron contactors (50A)
>http://tiny.cc/sXDp3 are a 3X better value and are tiny in comparison. The
>Type 70 is long in the tooth. As you recall this latest brushfire was
>sparked by troublemaker Jeff Skiba poking around to get information on
>higher current performance. He started this....
That's not a contactor but a fat relay. It IS rated for
switching the same loads as a type 70 Stancor but would
certainly not be suited for battery contactor service
where starter currents are also impressed on the contacts.
> >4) High hold current---16 ohm coil. Almost one amp.
>
>
> > Which is not an issue as long as the alternator
> > is running . . . you have power to burn. When the
> > alternator is not running, this device is turned
> > off for endurance mode operations.
>
>
>An ampere here, and ampere there...pretty soon you have real power waste.
>Our philosophies differ. I remember in 1960 when you could buy surplus
>aircraft and they'd come with full fuel tanks. Not anymore.
Philosophies differ? I'm not real sure what philosophy you're
embracing. I think I've been quite clear as to my own.
> >5) Low hold force. The specifications call for specific orientation.
> >2G rating?
>
> > I've tested these at over 12g. Where do you find any recommendations
> with respect to g-loading. I can tell you that the vertical orientation
> is to reduce potential for moisture ingress due to condensation and/or
> splash . . . as you've noted, they are not sealed. As a battery
> contactor, they are closed in all phases of flight and exceedingly difficult
to
> > force open with g-loads.
>
>You could be right on this. Type 70 specs are impossible to get on this,
>(and believe me I've tried). I interpret the orientation spec to be a
>g-load concern.
Can't imagine how you get this. Mounting top down adds gravity
to the spring tension and probably increases spreading
velocity by some factor. It also reduces a pooling opportunity
for ingested moisture. But to infer that this orientation
has something to do with consideration of g-loading in
aircraft is a real stretch. 99.9% of all such contactors
manufactured did not go into airplanes. It's a reasonable
extrapolation that their recommendations grew out of
consideration for the mass market applications as opposed
to aircraft.
> But Kilovac and Gigavac and others always spec g-load. Usually 10g's.
Those are not g-loading specs but shock and vibration
qualifications.
They do not address resistance to contact motion
while energized/de-energized under linear acceleration.
Folks have often latched onto those g-numbers and
translated them into potential for malfunction during
aerobatic maneuvers. They are unrelated.
If you're going to use spec sheets as a hammer, you
need to interpret them correctly lest the nail you
hit is the one on your thumb.
> >6) Wildly wrong for B&C to use coil suppression diodes on these. This
> >causes short lifetimes on the B&C parts.
>
> > I've also demonstrated that this is not true.
>
>
>As I said Bob, you are wonderfully on-the-mark about thousands of things,
>and only wildly wrong about only a few.
Make my day . . . show me where I went wrong.
>One Hundred Dollars U.S. to your favorite charity and a jar of jalapenos
>to you if an agreed upon third party will test the type-70 contactor using
>1N5401 Diodes vs. 18V SnapJacks for coil suppression in an agreed upon
>test. My winning requires you to never again espouse this bonehead notion.
Do your own tests. I've outlined exactly what I did, how
I made and interpreted the measurements. Where do you
find fault with the experiment? I explained in detail how
the authors of the oft quoted article correctly observed
an increase in drop-out delay cased by plain vanilla diodes
and then erroneously extrapolated this fact into a commensurate
reduction in contact spreading velocity (i.e. extended arcing
equals more wear).
It's a simple bench setup . . .
<snip>
> >Better yet, avoid all contactors and use manual switches if you can.
>
> > This IS a stretch Eric. It's true that contactors are the
> > most highly stressed devices on an airplane after generators
> > and followed by alternators. It's also true that they are
> > a significant maintenance item on EVERY airplane from the
> > C-150 through the Hawkers. But so are tires, batteries,
> > generators, etc. The artfully crafted system tolerates
> > these service life limitations without placing the aircraft
> > or occupants at risk. Can we really recommend that anyone
> > resort to manually operated high current switches (bring
> > high current conductors within reach of pilot) just to avoid
> > a service-life issue on a 100-our a year airplane?
>
>
>Bob, Stretching is a good, but not necessary thing. I recommend to my
>builder-friends using a Flaming River racecar battery switch to satisfy
>the FAA for the one-hand battery disconnect. That's what's going into my
>Glastar. No contactor needed. Most other contactors can go bye-bye too.
Good for you! And yes, the type 70 is a legacy product but
so are all the hammers and screwdrivers in my toolboxes. There
are a host devices that will function as battery contactors.
The Omron relay you cited is not one of them. If we're going
to give advice I'll suggest that it is specific to the
question and includes a suite of choices . . . and refrain
from unsubstantiated fear mongering especially in light
of repeatable experiments that demonstrate otherwise.
Show me where the interpretation of data in the diode vs. spreading
velocity experiment was wrong. Keep in mind too that contact
wear in switches and contactors is more tightly linked
to behaviors in CLOSING the contacts. Here the contacts
bounce . . . close, open and re-close up to a dozen times
in an ever decreasing gap where ARCING happens with each
opening. The coil suppression technology has nothing to do
with contact closing behaviors.
The GX11 Gigavac is an interesting product. I've seen their
RF vacuum relays for years but this was the first time I
was aware of a high current contactor. They don't sell through
distribution but I find that an old friend to mine is their
local rep. I left a voice mail message for him asking about
getting my hands on a GX11BAA. See:
http://aeroelectric.com/Mfgr_Data/Contactors/Gigavac/gx11.pdf
Note that this data sheet speaks to vibration and shock
ratings . . . NOT linear acceleration. Note further that
they do not offer a duty-cycle switched, low holding
current feature. I'll get one on order and look it over.
Bob . . .
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| Subject: | Acceleration ratings for contactors |
Just noticed that the spec sheet for the venerable
6041 series contactors at:
http://aeroelectric.com/Mfgr_Data/Contactors/Eaton_CH/6041SeriesPowerRelays.pdf
speaks to shock, vibration and ACCELERATION. The acceleration number
is relevant to applications in aircraft and other vehicles where
transient acceleration loads might be impressed on the device. This
value would include the de-energized condition where 10G would
not cause the contacts to close. However, while closed as a battery
or generator bus contactor, resistance to effects of g-loading
would be at least 2 times this value.
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: | Headset components |
I need to put a headset in my Shoei helmet that I use on my trike. I'm
reluctant to take apart a $100 headset to get the mic and speakers if it's
possible to do this with Rat Shack parts (or Digikey, Mouser, or.....).
Anyone out there have any recommendations, part numbers or required specs?
Thanks,
Rick
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| Subject: | Re: Headset components |
Possibly the headset from a motorcycle intercom will work. The are
already set up to fit in a motorcycle helmet. They are available from
about $20 on the bottom end to more that an aviation headset on the upper
end.
For what it's worth,
Steve
> I need to put a headset in my Shoei helmet that I use on my trike. I'm
> reluctant to take apart a $100 headset to get the mic and speakers if it's
> possible to do this with Rat Shack parts (or Digikey, Mouser, or.....).
> Anyone out there have any recommendations, part numbers or required specs?
>
> Thanks,
> Rick
>
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| Subject: | Re: Headset components |
Steve, A Nady intercom was the first thing I tried on the trike. The headset
fit right in the helmet but the unit allowed so much electrical noise in
that it was unusable. When one of the cords was accidentally cut I think I
discovered why. The cables are not shielded and used varnished wires on top
of that. By very careful use of the soldering iron I was finally able to
reconnect the wires, but I wasn't able to get the noise out. Trying to
interface it with my Icom A22 handheld was also a pain. I've got a Pilot
Avionics Pa 200 IK intercom now that plugs directly into the A22, seems
electrically isolated from the noise from the engine (HKS 700E four stroke),
and allows me to use any aircraft headset. Now I want the safety of my Shoei
full face helmet back and I'll be happy. Thanks fo rhte suggeston though.
Rick
On Wed, Jul 30, 2008 at 5:23 PM, <sttwig@wabroadband.com> wrote:
>
> Possibly the headset from a motorcycle intercom will work. The are
> already set up to fit in a motorcycle helmet. They are available from
> about $20 on the bottom end to more that an aviation headset on the upper
> end.
>
> For what it's worth,
>
> Steve
>
> > I need to put a headset in my Shoei helmet that I use on my trike. I'm
> > reluctant to take apart a $100 headset to get the mic and speakers if
> it's
> > possible to do this with Rat Shack parts (or Digikey, Mouser, or.....).
> > Anyone out there have any recommendations, part numbers or required
> specs?
> >
> > Thanks,
> > Rick
> >
>
>
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| Subject: | Re: AT150 Interrogation Light |
Thanks, Matt. You've given me several things to try. Yes, I do have a new cell
phone and the first thing I'll try is to turn it off and see what happens.
I also have dual electronic ignition and I'll do some experimenting there too.
One thing I've noticed is that one of the ignitions has begun to make a noise
in my headset. Basically I can hear the trigger wheel going past the crank
sensors, so I may have some wiring that is leaking through to the headset wiring
and possibly to the transponder too. Something to look at. Other than that
the ignitions seem to be operating fine, as is the alternator, however I have
no way of turning it off. The transponder acts normally when the engine isn't
running. I my area its very rural with no interrogation pulses until I get
at least 2000agl, and even those are a long way off, so I'm not getting bombarded
with pulses.
However, I do have some things to try. Thanks.
Also, thanks to the others who offered help.
Deke
mprather(at)spro.net wrote:
> Maybe you have something in the airplane generating noise which causes the
> transponder to reply - even though it wasn't interrogated by an actual
> radar signal. How's the audio in your comm radio? Any new noise? Off
> the top of my head, maybe you have a bad spark plug wire, or alternator
> diode or something like that. Does your engine have dual ignition
> systems? If yes, does the transponder behave the same way on each of them
> separately? Can you turn the alternator off and still run the txp from
> battery (as a test)? I doubt you have a DME in a Kitfox, but they operate
> in the same band as the transponder so might be a source of interference.
>
> As a long shot, possibly your cell phone is setting it off. Did you get a
> new phone? Does it misbehave with the phone turned off?
>
> I can't recall if the AT150 has a remote ident button, but maybe the wire
> that connects that circuit isn't isolated properly. I think those work by
> grounding the wire. Vibration might cause that wire to rub against
> ground. In reality, the pin in the shell connector for that function
> probably doesn't even have a wire in it, so that's probably not the issue.
>
> Maybe the reply discrimination circuit is messed up in your txp. Possibly
> a radio shop has a loaner unit you could s
>
>
> wap into the tray. Or maybe
> they can test the unit for that functionality.
>
>
> Regards,
>
> Matt-
>
>
>
>
> > I have a Narco AT150 transponder in a Kitfox 5 with the antenna on the
> > belly with a 5.5" ground plate. It seems to be working fine according to
> > ATC. Good data and the mode C is accurate. However, the interrogation
> > light is on steady, rather than blinking as the radar sweeps past it. It
> > used to be just fine, but at some point it began to act differently where
> > it would flicker, especially on the ground. Now, if the engine is off and
> > I activate it, the interrogation light comes on for a few seconds, then
> > turns off. I believe that's how it's supposed to act. However, when
> > flying, it seems to come on steady and stay that way with an occasional
> > flicker during flight. As I said, ATC says it's working fine.
> > Has anyone seen this? Any idea what my problem is? Several times I've
> > removed it, cleaned and lubed the contacts, and replaced it with the same
> > results. Since it's working fine, I'm not to worried about it, but I'd
> > like to get this light working like it's supposed to.
> > Thanks for any help offered.
> > Deke
> >
> >
> >
>
--------
Deke Morisse
Kitfox S5 TD
NSI/CAP
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=195814#195814
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| Subject: | Re: AT150 Interrogation Light |
At 06:08 PM 7/30/2008 -0700, you wrote:
>
>Thanks, Matt. You've given me several things to try. Yes, I do have a
>new cell phone and the first thing I'll try is to turn it off and see what
>happens. I also have dual electronic ignition and I'll do some
>experimenting there too. One thing I've noticed is that one of the
>ignitions has begun to make a noise in my headset. Basically I can hear
>the trigger wheel going past the crank sensors, so I may have some wiring
>that is leaking through to the headset wiring and possibly to the
>transponder too. Something to look at. Other than that the ignitions
>seem to be operating fine, as is the alternator, however I have no way of
>turning it off. The transponder acts normally when the engine isn't
>running. I my area its very rural with no interrogation pulses until I
>get at least 2000agl, and even those are a long way off, so I'm not
>getting bombarded with pulses.
>However, I do have some things to try. Thanks.
>Also, thanks to the others who offered help.
Got in on this thread late but as others have noted,
the transponder receiver is rather 'twitchy' with
respect mistaking incoming noises as a bona fide
"paint" from a ground based radar.
A technician I used to work with had some rubber
bands permanently installed over the hand grip
on his line operated electric drill. I asked what
they were for and he was happy to demonstrate. Use
the rubber bands to hold the trigger made and then
lay the drill on the floor right under the transponder
antenna. From outside the cockpit you could see the
reply light going nutso. He had one of those altitude
and squawk code receiver/readouts that could then
be used to see if the altimeter encoder was reading
the same as the pitot-static test set altitude.
The drill motor and the el-cheeso readout accessory
took the place of some rather expensive test equipment
for doing pitot static tests.
Try pulling all the breakers/fuses except transponder.
See if effects go away. Reinstall feeder protection
one device at a time to see if you can identify the
one that's upsetting the transponder. But all who
have responded to this thread have identified possibilities
for pesky little noises that might be causing the
problem. It doesn't take much.
Bob . . .
Message 10
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| Subject: | Re: Z-19/RB Question |
Mike,
That's exactly how I've operated our RV for years. My reasoning for
doing so is that I only have to turn off one switch (the master) in case
of alternator failure. I don't have to worry about turning on the alt
feed before doing so to avoid rebooting stuff. In fact, when my
alternator quit working on my way to British Columbia last spring,
that's what I did. Flipped one switch and kept going. Had enough battery
for an hour's flight, landing at a towered airport for gas, a start and
departure and another 45 minutes of flight and still had enough in the
battery for a start after replacing the alternator. I turned off stuff
we didn't need, but kept the electronic ignition, transponder and GPS
going. Turned on and used the Com when I needed to and didn't worry
about maintenance till we stopped at our intended destination for the night.
I turn on the alternate feed, check atis while I'm inserting my ear
canal headset to make sure I've got them in right then I turn on the
master, start and operate normally. My voltmeter is on the E-Buss so, if
I do turn the alt feed off, I'm reading a voltage somewhat lower than
the actual charging voltage. I don't have to do any math to see what the
alternator is up to.
Pax,
Ed Holyoke
mikef wrote:
>
> Bob,
>
> Understood, that EBus switch is ALTERNATE path to powering the EBus. And as you
said, turn it on, check ATIS are all good preflight procedures to test this
path.
>
> I just wanted to confirm that once you are started and the alternator is running
smoothly, it would do no harm to leave the EBus switch turned on (closed)
during normal operations.
>
> Thanks,
>
> Mike
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=195343#195343
>
>
>
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