Matronics Email Lists :: View topic - kitfox /rotax 912 wiring diagram (variation on Z-16)

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

kitfox /rotax 912 wiring diagram (variation on Z-16)

Matronics Email Lists Forum Index -> AeroElectric-List

View previous topic :: View next topic

Author Message

nuckolls.bob(at)aeroelect
Guest

Posted: Tue Dec 03, 2013 6:39 pm Post subject: kitfox /rotax 912 wiring diagram (variation on Z-16)

 	  Quote: 	
		  

 I thought about this a lot before I stuck all that stuff on the E-bus… strictly speaking I don’t need:

 -         Transponder/Alt encoder

 -         Autopilot

 -         AHRS

 -         Cigar Lighter 12V and USB supplies

 But it’s nice to be able to have them (e.g. if you’re going to be landing in a field that’s new to you, you can have the A/P on while you look at the chart, etc), so I figured I would leave them there and turn them off if necessary (except for the AHRS but that only consumes 0.3A).  Is this not advisable? (I’m a low time PPL so I’m completely open to suggestions in this area). 	


   Do the load analysis with a consideration of how

   you would maximize the utility of the battery's

   stored energy toward a design goal. First, how

   long would you like to operate battery only?

   A lot of design decisions are made with no

   more conviction to an idea than "this is better

   than that" . . . but without quantification

   as to how all the "betters" add up to meeting

   a design goal. Folks who buy/fly TC aircraft are

   relieved (or should I say deprived?) of that duty.

   Folks paid to worry have decreed that John Q.

   Public pilot is not properly prepared to accept

   such responsiblity . . . so they say, "Don't worry

   . . . we've taken care of all that worry stuff . . .

   just memorize the holy-watered pilot's operating

   handbook and all will be right with the universe."



  	  Quote: 	
		    Consider re-assigning supply points for some

   of the items on the avionics bus. 	


   Write you own 'stage play' or better yet 'cockpit

   play' in which you are the star performer. Plan a

   mission with the highest order of risk wherein loss of

   engine driven electrical power would be the most perplexing.

   It's interesting that MOST plane/pilot/mission

   scenarios flown in both TC/OBAM aircraft seldom

   elevate the importance of alternators and batteries

   to levels of critical concern.



   I cannot recall one instance in 33 years/1000+

   hours as pilot where loss of an alternator was

   more than an 'oh fooey!' event. I've personally experienced

   one loss of alternator event on a cross-country

   but completed both outbound and return legs battery-

   only so the owner could deal with the broken alternator

   on his own turf. That same trip also presented loss of

   airspeed indicator (spider egg sack waaayyy back

   in pitot tube). Both events presented a challenge

   for assuming a new mode of operation. But both legs

   were day-vmc ops in and out of uncontrolled

   fields . . . I normally navigated with dual

   AA powered, GPS315 receivers on the glare shield

   . . . so no big deal.

   

   I have conducted numerous long-leg ops at night over

   unfriendly terrain but never suffered the indignity

   for loss of alternator. NONE of the airplanes I

   was flying featured anything like an e-bus. I had

   absolutely no idea as to the health of the battery

   beyond the fact that it cranked the engine.

   My personal plan-b calls for me to arrive at airport

   of intended destination whether the panel was 'lit up'

   or not.



   Nonetheless, Hollywood playwrights, dark-n-stormy

   night stories in the journals and exciting anecdotes

   over beers (combined with our terrestrial perceptions

   of batteries in general) give rise to worries about

   both alternators and batteries.



   Getting back to your particular study of options,

   it would be well to set some design goals. What

   battery only endurance would you like to strive for?

   Given what you know about how the airplane will be

   used, you might start with some notion of just how

   long you'd like to operate battery only. About 1/4

   of my use of winged machines calls for burning off

   most of a full fuel load . . . so personally, my e-bus

   operations would shoot for 3-4 hours as a design

   goal.  Your's may be less.



   My plan-b flight bag hardware consists of GPS

   receivers (two actually . . . I use them full time),

   hand-held transceiver with vor/loc capabilities,

   and a flashlight. Something you can do in your airplane

   that I didn't get with a TC rental is connection

   for your hand-held to the external antenna.



   For the way I use airplanes, I enjoy a high order

   probability that I'll get where I want to

   go . . . whether I'm using an A-36 with lots of

   stuff that doesn't work or a J-3 that didn't

   have any stuff to begin with.



   Okay, what are your personal design goals? Which

   items on your panel will address your needs for

   continued flight battery-only until destination

   airport is in sight?  What are the energy demands

   for those items? How long do you want to run them?



   You can certainly have other things on the e-bus

   but items not needed for the en route, endurance

   mode of flight should be fitted with on-off switches

   so that you can shed those loads.

  	  Quote: 	
		   

 By replaced, do you mean I should add a fuse between the Dynamo and the Voltage regulator?  I don’t currently have a fuse on the b-lead, I don’t think. 	


   What passes for a "b-lead" on the PM/R-R

   system is that wire that runs from OUTPUT

   terminal of the R-R, through the control

   relay and to the system. Since it ties

   directly to a battery-fed, fat-wire it's

   a good idea to protect it at some level

   well above the output capability of the

   alternator. 30A fuse is a good choice.

  	  Quote: 	
		   

 I’m confused… I thought the b-lead is wire that goes between the dynamo and the voltage regulator.  How can it be connected to the battery contactor? 	


   No, the output from the dynamo is AC voltage

   conducted to a controlled, full-wave rectifier

   in the rectifier-regulator. The analogous

   path in a wound-field alternator would be

   wires between the stator windings and

   a 3-phase rectifier array . . . all this

   is INTERNAL to the legacy alternator.



  	  Quote: 	
		   

 I incorporated them following the suggestions on the Infinity Grip order form ( http://www.infinityaerospace.com/gripwire.pdf) and against the better judgment of my expert friend who helped me with the wiring.   I thought it might be a good idea to have them handy in case of an engine failure in order to attempt a restart.  But in hindsight, it was maybe not such a great idea.  There is also the potential, any time the master is on on the ground, to accidentally hit the starter button and swing the prop. 	


    The more I think about it, the more I

    dislike putting all those functions on

    the stick. Non-standard "conveniences" can

    translate into un-intended consequences.

    Further, the likelihood that a start-button on

    the stick will ever be critical to saving

    the day is exceedingly low if not zero.



    If the engine quits at altitude, you've

    got plenty of time to manage the situation

    with the legacy suite of controls. If you're

    so low that mere seconds count, then fiddling

    with the engine is a distraction from the

    prime directive of the day . . . endeavor

    to walk away. 



    In a TC aircraft you will find some combination

    of following buttons on the wheel or stick.



    Trim: UP, DN, LT, RT

    Push to Transmit

    Push to Intercom

         and MAYBE . . .

    Master Disconnect that removes power to all motors

    that drive flight surfaces.



    Inadvertent operation of any of theses switches

    does not create a hazard to sheet metal or

    bones . . . nor do they depart from legacy

    cockpit behaviors that are the stock and trade

    of most pilots.



    We still need a list of electro-whizzies in

    your airplane that use power . . . and

    partitioning of scenarios for when they are

    expected to be in service. 



 

   Bob . . .     [quote][b]

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

uuccio(at)gmail.com
Guest

Posted: Tue Dec 10, 2013 8:24 am Post subject: kitfox /rotax 912 wiring diagram (variation on Z-16)

Getting back to your particular study of options,

  it would be well to set some design goals. What

  battery only endurance would you like to strive for?

  […] my e-bus

  operations would shoot for 3-4 hours as a design

  goal.  Your's may be less.

 

Four hours sounds like a good number.  Missions will be Day VFR only; some mountainous terrain and open waters.   



  My plan-b flight bag hardware consists of GPS

  receivers (two actually . . . I use them full time),

  hand-held transceiver with vor/loc capabilities,

  and a flashlight. 

 

I have an iPad which has aeronautical charts.  It will be connected to the USB charger to keep it charged when the alternator is working and will serve as a backup GPS if the alternator stops working.    My hand-held doesn’t have VOR/LOC capabilities, maybe I’ll pick one of those up next time I’m in the US (its’ cheaper there).

 

Something you can do in your airplane

  that I didn't get with a TC rental is connection

  for your hand-held to the external antenna.

That’s definitely something I’m interested in; is there a good way to do it without installing a separate antenna?

 

  What passes for a "b-lead" on the PM/R-R

  system is that wire that runs from OUTPUT

  terminal of the R-R, through the control

  relay and to the system. Since it ties

  directly to a battery-fed, fat-wire it's

  a good idea to protect it at some level

  well above the output capability of the

  alternator. 30A fuse is a good choice.

OK, I’ll do that.



I incorporated them following the suggestions on the Infinity Grip order form ( http://www.infinityaerospace.com/gripwire.pdf) and against the better judgment of my expert friend who helped me with the wiring.   I thought it might be a good idea to have them handy in case of an engine failure in order to attempt a restart.  But in hindsight, it was maybe not such a great idea.  There is also the potential, any time the master is on on the ground, to accidentally hit the starter button and swing the prop.



   The more I think about it, the more I

   dislike putting all those functions on

   the stick. Non-standard "conveniences" can

   translate into un-intended consequences.

   Further, the likelihood that a start-button on

   the stick will ever be critical to saving

   the day is exceedingly low if not zero.



   If the engine quits at altitude, you've

   got plenty of time to manage the situation

   with the legacy suite of controls. If you're

   so low that mere seconds count, then fiddling

   with the engine is a distraction from the

   prime directive of the day . . . endeavor

   to walk away. 

Yup, makes sense.



   In a TC aircraft you will find some combination

   of following buttons on the wheel or stick.



   Trim: UP, DN, LT, RT

   Push to Transmit

   Push to Intercom

        and MAYBE . . .

   Master Disconnect that removes power to all motors

   that drive flight surfaces.



   Inadvertent operation of any of theses switches

   does not create a hazard to sheet metal or

   bones . . . nor do they depart from legacy

   cockpit behaviors that are the stock and trade

   of most pilots.



   We still need a list of electro-whizzies in

   your airplane that use power . . . and

   partitioning of scenarios for when they are

   expected to be in service. 



I’ve revised my Load Analysis (see attached excel/pdf), and it indicates that with a 24Ah Batt at 70% capacity, I should get 4 hours electrical endurance…

 

Sacha

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

Load_Analysis_1.25.pdf

Description:

Download

Filename:

Load_Analysis_1.25.pdf

Filesize:

25.29 KB

Downloaded:

198 Time(s)

Load_Analysis_1.25.xlsx

Description:

Download

Filename:

Load_Analysis_1.25.xlsx

Filesize:

32.69 KB

Downloaded:

198 Time(s)

Display posts from previous:

	Matronics Email Lists Forum Index -> AeroElectric-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum