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jessejenks(at)hotmail.com
Guest

Posted: Thu Jan 07, 2010 1:20 pm Post subject: planning

From: jessejenks(at)hotmail.com

To: jessejenks(at)hotmail.com

Subject: RE: AeroElectric-List Digest: 27 Msgs - 01/06/10

Date: Thu C 7 Jan 2010 12:58:03 -0800

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 	  Quote: 	
		   Time: 10:17:27 AM PST US

 From: "Robert L. Nuckolls C III" <nuckolls.bob(at)aeroelectric.com>

 Subject: AeroElectric-List: Electrical System Planning

 At 11:45 AM 1/6/2010 C you wrote:

 I'm planning to use Z-11 and have an occasional-IFR panel with a

 Grmin 430 and Dynon EFIS. I'm still at the very basic planning phase.

    Do you plan to have vacuum driven instruments?

    If not why not Z13/8?

    No C I won't have a vacuum pump. I will reconsider Z13/8 C but I had deemed it overkill for my mostly VFR bushplane.  

     I do want to have a "get home" IFR capability C but as one who has spent many hours inside clouds in well equipped

     airplanes and being scared occasionally C mostly by icing C I view a single engine piston airplane without              anti-ice systems as a not-very-good IFR platform. Also I like 

     your philosophy that using a properly maintained RG battery is the simplest way to add reliability to the

     electrical system. I also have Slick mags C and with backup batteries in the EFIS and a handheld gps/radio C

     I don't see the electrical system as the most critical system for the guarantee of a safe landing. I am definitely 

     willing to change my mind though. 

 	  Quote: 	

 1)With the P.P. alternator I will obviously not have the separate 

 voltage regulator C but do I still need the crowbar over voltage protection?

    Plane Power INCLUDES crowbar OV protection on their OBAM

    aircraft alternators.

    Thank you. Sure enough C the schematic that came with my alternator says right at the top;

     "12 volt 60 amp experimental alternator w/internal voltage regulator and over voltage protection".

     Do you think this system is as good as C not as good C or better than using an alternator with external regulator

     and OV protection?  I think I remember you saying in the past that you tested the Plane Power alternator.

> 

 	  Quote: 	
		   2)The Skytec starter has it's own contactor to engage the gear C and 

 apply power to the motor. According to Skytec C I don't need a 

 separate contactor for the starter if I use a 20+amp starter switch C 

 which I plan to do (toggle mag switches and separate starter switch) 

 Are there any cautions for not using a separate starter contactor?

     No.

     Bob . . .

    I like the simple "NO" answer C however now after doing some more reading I have a couple more questions;

    I came across your Z-22 C fix for run on starters with PM motors C which the Skytec is. You suggest a relay to replace

     the contactor. Further Skytec suggests on their website that if wiring the starter without a seperate contactor C to put

    a diode at the start switch to lengthen service life of the switch. This all leaves me a little confused. What is the main 

    issue here C protecting the start switch C or preventing possible damage to the starter or flywheel gears C or both C or

    something else? Should I use a diode or a relay C or both C or neither?

 	  Quote: 	
		     And another question; I saw your link to the article below. I found the philosophical discussion very   interesting C I also noticed that in that article you reccomend a 70 or 80 amp fuse in the alternator    B-lead which is different than the Z-figures where an ANL 60 curret limiter is shown. Reading note 10 I   see that the current limiter is a modern upgrade to the fuse or breaker C but is 60 amps still the   reccomended rating (not 70 or 80)?   Thanks. Have you read . . . http://www.aeroelectric.com/articles/fusvbkr2.html 	

 	  Quote: 	

Your E-mail and More On-the-Go. Get Windows Live Hotmail Free. Hotmail: Free C trusted and rich email service.   [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Jan 08, 2010 3:06 pm Post subject: planning

your philosophy that using a properly maintained RG battery is the 

simplest way to add reliability to the

electrical system. I also have Slick mags, and with backup batteries 

in the EFIS and a handheld gps/radio,

I don't see the electrical system as the most critical system for the 

guarantee of a safe landing. I am definitely

willing to change my mind though.



   If you're comfy, so be it. The neat thing about Z-13/8 is that

   it's an easy step up from Z-11 at any later time giving you

   unlimited 8-10A of e-bus loads for a weight penalty that's

   a small fraction of the vacuum system that came out (or wasn't

   there in the first place).

-------------------------

   Plane Power INCLUDES crowbar OV protection on their OBAM

   aircraft alternators.



Thank you. Sure enough, the schematic that came with my alternator 

says right at the top;

"12 volt 60 amp experimental alternator w/internal voltage regulator 

and over voltage protection".

Do you think this system is as good as, not as good, or better than 

using an alternator with external regulator

and OV protection?  I think I remember you saying in the past that 

you tested the Plane Power alternator.



    I have not tested any PP products. However I did

    talk to one of the techno-wienies there right after

    I was made aware of their offering. I confirmed that

    they had adopted a crowbar ov protection technique

    and avoided the b-lead contactor by going inside

    the alternator to bring out the field excitation

    supply line. All in all, an elegant solution.



    The design goal for the AEC9004 IR alternator controller

    is to achieve any time, any conditions, zero-risk pilot

    control of an UNMODIFIED internally regulated alternator.

    Aside from differences in design goals, I'd judge the

    PP products to be entirely suited to the task.



2)The Skytec starter has it's own contactor to engage the gear, and

apply power to the motor. According to Skytec, I don't need a

separate contactor for the starter if I use a 20+amp starter switch,

which I plan to do (toggle mag switches and separate starter switch)

Are there any cautions for not using a separate starter contactor?



    No.



I like the simple "NO" answer, however now after doing some more 

reading I have a

couple more questions; I came across your Z-22, fix for run on starters with PM

motors, which the Skytec is. You suggest a relay to replace the 

contactor. Further

Skytec suggests on their website that if wiring the starter without a 

separate contactor,

to put a diode at the start switch to lengthen service life of the 

switch. This all

leaves me a little confused. What is the main issue here, protecting the start

switch, or preventing possible damage to the starter or flywheel 

gears, or both, or

something else? Should I use a diode or a relay, or both, or neither?



    We're getting several issues tangled together here. First,

    unless the builder is going to use a robust starter pushbutton

    designed for abuse by two-stage contactor/solenoids then

    some sort of "buffering" is worth considering.



    Assuming you still wish to control the Skytec contactor

    directly, then adding a relay per Z-22 is the way to

    go about it. Assuming you already have or wish to use

    the single stage starter contactor, then you don't want

    to "jumper" the Skytec solenoid coil to the main terminal.

    This gives rise to the "run on" phenomenon described. In

    this case, you take the "I" terminal from the external

    single stage contactor over to the Skytec's coil

    terminal as suggested by



http://aeroelectric.com/Pictures/Schematics/Vans_Starter_Wiring_Lg.jpg



    This has the advantage of (1) reducing stress on the

    starter push-button or switch and (2) preventing

    delayed disengagement during spin down on a PM

    starter. Kinda slick. Wish I'd thought of it.



    Now with most contactors, a diode across the

    coil is a good thing to contemplate. On Van's drawing

    cathode would go to "S" and anode to ground (case).



    You could also consider a diode from the Skytec

    coil terminal (cathode) to ground (anode).



And another question; I saw your link to the article below. I found 

the philosophical discussion very

interesting, I also noticed that in that article you recommend a 70 

or 80 amp fuse in the alternator

B-lead which is different than the Z-figures where an ANL 60 curret 

limiter is shown. Reading note 10 I

see that the current limiter is a modern upgrade to the fuse or 

breaker, but is 60 amps still the

recommended rating (not 70 or 80)?



    Yes, there was a bit of a kerfuffle here on the List

    about 13 years ago. See:



http://www.aeroelectric.com/articles/fusvbkr2.html



    Early on we were pretty stoked up about using

    JJN/JSS fuses as lower cost, bolt-on b-lead

    protection. That idea proved less than ideal

    when a number of builders reported opening their

    60A fuse on a 60A alternator (so we up-sized to

    70A . . . probably should have jumped to 100A).



    Other builder noted that these fuses were not

    very robust mechanically . . . they reported

    end caps pulling off the fuse body. Sooooooo . . .

    the ANL limiters came to the rescue. Their

    electrical robustness. See:



http://www.aeroelectric.com/articles/anl/anlvsjjs.html



    Note that a 35A ANL would probably take good

    care of the b-lead on a 60A alternator . . .

    but a 60A is good too. This is NOT a finely tuned

    protection task. Fault currents in the b-lead

    will be hundreds to perhaps over 1000 amps!



    Bob . . .

jessejenks(at)hotmail.com
Guest

Posted: Mon Jan 11, 2010 8:45 am Post subject: planning

Bob wrote:



    We're getting several issues tangled together here. First C

    unless the builder is going to use a robust starter pushbutton

    designed for abuse by two-stage contactor/solenoids then

    some sort of "buffering" is worth considering.

 

    Assuming you still wish to control the Skytec contactor

    directly C then adding a relay per Z-22 is the way to

    go about it. Assuming you already have or wish to use

    the single stage starter contactor C then you don't want

    to "jumper" the Skytec solenoid coil to the main terminal.

    This gives rise to the "run on" phenomenon described. In

    this case C you take the "I" terminal from the external

    single stage contactor over to the Skytec's coil



Thanks Bob. I am really struggling to absorb as much as I can from this discussion while also readying everything else I can find from your website and other sources C while also trying to learn Aeroelectric 101... My B-lead is about to smoke.  So C I guess the jumper is what causes the run-on C and whatever I do I don't want it in there. I don't already have a separate contactor C so the way I understand it my options are; 1) use Z-22 with a relay C 2) just use a push button rated for 30 amps and no relay.

Can you explain why run-on is a problem if it only lasts a couple seconds? 

Jesse

 		 	   		  Hotmail: Powerful Free email with set/01/' target='_new'>Get it now.  [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Tue Jan 12, 2010 6:36 am Post subject: planning

 	  Quote: 	
		  So, I guess the jumper is what causes the run-on, and whatever I do 

I don't want it in there. I don't already have a separate contactor, 

so the way I understand it my options are; 1) use Z-22 with a relay, 

2) just use a push button rated for 30 amps and no relay.


	


   Yes.



 	  Quote: 	
		  Can you explain why run-on is a problem if it only lasts a couple seconds?


	


   The design goal for engagement solenoids with

   integral contactors is to effect immediate retraction

   of the pinion gear when the starter button is

   released. There ARE over-run clutches in the starter

   gearing that prevents the engine from back-driving

   the starter. These are VERY important . . .



   For a small starter to be efficient, the armature

   is highly geared down to crank the engine at 150

   to 300 rpm. when the engine starts, it's suddenly

   running at 4x that speed. Were it not for over-run

   clutches, this would immediately spin the armature

   up to 4x it's operating speed and probably throw

   windings, commutator bars, or strip gear teeth.



   The run-on phenomenon simply exercises the over-run

   mechanism and increases pinion wear for reasons that

   do not add value . . . and would not happen except

   for an unintended consequence of using the solenoid/

   contactor in a manner contrary to original design

   goals.



   Bob . . .

jessejenks(at)hotmail.com
Guest

Posted: Thu Jan 21, 2010 11:35 am Post subject: Planning

 	  Quote: 	
		  Hopefully this is a dumb question:With an aft battery installation C does the main bus feed wire come from the starter? 	
Also C does the crankcase ground strap connect to the firewall forest of tabs ground bus through bolt C or does it need its own more substantial bracket to bolt to? 



 	  Quote: 	
		  Thanks.Jesse 	
 		 	   		  Hotmail: Free C trusted and rich' target='_new'>Get it now.  [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Thu Jan 21, 2010 7:42 pm Post subject: Planning

At 01:32 PM 1/21/2010, you wrote:



 

  	  Quote: 	
		   	  Quote: 	
		  

Hopefully this is a dumb question:

With an aft battery installation, does the main bus feed wire come from

the starter?

[/b] 	
	


   Battery side of the starter contactor. Or if the

   contactor is built into the starter, yes, right

   from the starter.



  	  Quote: 	
		   Also, does the crankcase ground strap connect to the firewall forest of tabs ground bus through bolt, or does it need its own more substantial bracket to bolt to? 	


   To the bolt.

  

   Bob . . .    [quote][b]

jessejenks(at)hotmail.com
Guest

Posted: Fri Jan 22, 2010 9:59 am Post subject: Planning

Thanks Bob C

yeah C I forgot to mention I decided to omit the starter contactor and will use the built in one.

Jesse



Date: Thu C 21 Jan 2010 21:40:13 -0600

To: aeroelectric-list(at)matronics.com

From: nuckolls.bob(at)aeroelectric.com

Subject: Re: AeroElectric-List: Planning



  At 01:32 PM 1/21/2010 C you wrote:



 

  	  Quote: 	
		   	  Quote: 	
		  Hopefully this is a dumb question:With an aft battery installation C does the main bus feed wire come fromthe starter? 	
	


   Battery side of the starter contactor. Or if the

   contactor is built into the starter C yes C right

   from the starter.



  	  Quote: 	
		   Also C does the crankcase ground strap connect to the firewall forest of tabs ground bus through bolt C or does it need its own more substantial bracket to bolt to? 	


   To the bolt.

  

   Bob . . .     	  Quote: 	
		  <===================== 	
 		 	   		  Hotmail: Trusted email with Microsoft’6/direct/01/' target='_new'>Sign up now.  [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Jan 22, 2010 11:16 am Post subject: Planning

At 11:55 AM 1/22/2010, you wrote:

 	  Quote: 	
		  Thanks Bob,

yeah, I forgot to mention I decided to omit the starter contactor 

and will use the built in one.


	


   Understand. Then the BAT terminal on your starter becomes

   the forward power distribution point. Your alternator b-lead

   would tie in there too.



   Consider an ANL current limiter for the alternator B-lead

   where the BAT end of the limiter base could become the

   distribution point. This would prevent piling all those

   wires on one terminal out on the engine.



   Bob . . .

jessejenks(at)hotmail.com
Guest

Posted: Fri Jan 22, 2010 1:41 pm Post subject: Planning

Great!

Thanks again. I had been visualizing the ANL setup that you suggest as one possibility. It makes a lot of sense C especially since the ANL seems to be you're preferred method of protecting the b-lead. What the other option has going for it is a real short b-lead wire directly from alt. to starter. Of course then I'm forced to use an inline fuse.

I'm leaning toward an ANL on the firewall. 

 	  Quote: 	
		   Date: Fri C 22 Jan 2010 13:14:44 -0600

 To: aeroelectric-list(at)matronics.com

 From: nuckolls.bob(at)aeroelectric.com

 Subject: RE: Planning

 --> AeroElectric-List message posted by: "Robert L. Nuckolls C III" <nuckolls.bob(at)aeroelectric.com>

 At 11:55 AM 1/22/2010 C you wrote:

 >Thanks Bob C

 >yeah C I forgot to mention I decided to omit the starter contactor 

 >and will use the built in one.

    Understand. Then the BAT terminal on your starter becomes

    the forward power distribution point. Your alternator b-lead

    would tie in there too.

    Consider an ANL current limiter for the alternator B-lead

    where the BAT end of the limiter base could become the

    distribution point. This would prevent piling all those

    wires on one terminal out on the engine.

    Bob . . . 

 		 	   		  Hotmail: Free C trusted and rich email service. Get it now.

nuckolls.bob(at)aeroelect
Guest

Posted: Fri Jan 22, 2010 4:03 pm Post subject: Planning

At 03:05 PM 1/22/2010, you wrote:

 	  Quote: 	
		  Great!

Thanks again. I had been visualizing the ANL setup that you suggest 

as one possibility. It makes a lot of sense, especially since the 

ANL seems to be you're preferred method of protecting the b-lead. 

What the other option has going for it is a real short b-lead wire 

directly from alt. to starter. Of course then I'm forced to use an inline fuse.

I'm leaning toward an ANL on the firewall.


	


    I think that would be my choice as it

    handles logistics for a power distribution

    point nicely.



    Bob . . .

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