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Alternator problem?
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versoelectric(at)GMAIL.CO
Guest

Posted: Sat Jun 27, 2015 5:34 pm Post subject: Alternator problem?

On Jun 27, 2015, at 4:40 PM, "user9253" wrote:

 	  Quote: 	
		   The over-voltage and low voltage features of the LR3 are not needed in your application if the VP-X provides over-voltage and the EFIS gives low voltage warning.


	


Does the VP-X initiate a crowbar in the presence of over-voltage, or simply report it through alarm output?



Eric

millner(at)me.com
Guest

Posted: Sat Jun 27, 2015 7:22 pm Post subject: Alternator problem?

Bob,



In our '70's Cardinals, Cessna installed an electrolytic capacitor across the OV unit to minimize such trips...



Paul

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Jun 28, 2015 8:18 am Post subject: Alternator problem?

 	  Quote: 	
		  

 You just went over my head with "brush-bounce". 	


    The term "bounce" is probably inappropriate . . .

    "discontinuity" is probably a better description.

    Brush bounce is a real phenomenon usually promoted

    by out-of-round slip rings or gross contamination

    of the surface.



    An artfully crafted slip ring receives final

    finish with the armature shaft captured between

    centers and cut with a diamond tipped tool with

    cutting depth and rates so tiny that the finish

    is mirror smooth.



    Now, press a chunk of carbon to that surface while

    it romps along at 200 inches per second . . . and

    that 'smoothness' can take on a new character

    as tiny bits of material transfers from the brush

    to the slip-ring. Over time measured in hours,

    a 'film' is formed on the copper. The charcater and

    rate of deposition is a function of current magnitude

    and direction in the brush, moisture, brush material makeup,

    pressure, and probably a few other things the sub-microscopic/

    molecular level. See:  http://tinyurl.com/q9q62eb



    It ALWAYS happens and is built into the nature of

    machines with brushes.  Problems can manifest when

    some feature of associated electronics is

    sensitive to the discontinuity.  The 30 year arm

    wrestling match with the TC regulator has roots

    in just such a sensitivity



 

  	  Quote: 	
		  I'm all for grins! Can you give me an idea where to get or how to build this filter? 	


    What is the center-to-center distance for 

    the F1 to F2 terminals on your alternator?



    I crafted a filter to conduct some experiments

    on the problem aircraft that seemed to 'fix' the

    problem . . . more appropriately 'mask' the

    problem.  It didn't fix the design descrepancy

    in the regulator . . . only broke the propagation

    mode between the antagonist (perfectly normal

    brush behavior) and the victim (an uber-sensitive

    OV sense mechanism).



    As a quick, interim experiment, try connecdting a high

    quality, 1 uF capacitor from F1 to F2 on your alternator.

    NOT an electrolytic but a some form of metal-film device.

    I've got a few hundred laying around . . . can send

    you one of those right away.



 

   Bob . . .    [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Jun 28, 2015 9:41 am Post subject: Alternator problem?

At 06:40 PM 6/27/2015, you wrote:

 --> AeroElectric-List message posted by: "user9253" <fransew(at)gmail.com>

 Directions for making a filter:

  http://www.sanantoniohams.org/tips/whine.htm

 > You just went over my head with "brush-bounce".

 Alternators have bushes that ride on slip rings.  If the rings are not concentric, the brushes will move up and down in their holders.

   . . . and under some conditions, experience

   periodic disconnections from the slip ring . . .  

   Which is probably not the phenomenon were

   working with here . . . as described in my

   recent post, the discontinuity of interest

   may have more to with quality of brush-track

   than from mechanical imperfections in surface

   or concentricity . . . but in any case SHOULD

   NOT be a component of root cause for OV trips

   in a well design OV sense system.

   By the way, it's been a persistent notion  in some

   circles for decades that 'automotive' hardware

   with brushes are ill-suited to use on aircraft due

   to effects of altitude leading to mis-interpreted

   assumptions that atmospheric pressure has a profound

   effect on brush performance. As pointed out in the

   the article I cited earlier, MOISTURE is a high-influence

   predictor of brush performance . . . and failure to

   perform at altitude has a lot to do with humidity

   and nearly nothing to do with altitude.

   "Altitude rated" brushes are really "low humidity

   rated" devices with chemistry added to the brush-makeup

   that compensates for reduced atmospheric moisture at

   altitude. But even those effects are much more pronounced

   on high current density brushes that ride on commutators

   as opposed to 3A max, 1A normal loads on alternator

   slip-rings. The collective experience of both TC

   and OBAM aviation communities have demonstrated that

   altitude effects are VERY low on the totem-pole

   of stresses that raise risk.

 > can you give me some idea of where I may have a disconnection in the "discontinuity in assembly of simple-ideas that govern performance

 I get the impression that Bob is inferring that he does not trust the VP-X.

   Didn't say that. What I'm saying is that I do

   not have enough information about the VP-X OV

   protection philosophy to discount the possibility

   that NORMAL alternator-noises are participating in nuisance

   trips. 

 I suggest that instead of pulling the alternator, that you replace the voltage regulator with a generic Ford VR166 or equivalent.  There is a list in Bob's book.  The over-voltage and low voltage features of the LR3 are not needed in your application if the VP-X provides over-voltage and the EFIS gives low voltage warning.

   An excellent experiment. If the VR-166 style

   regulators are presently fitted with OV protection,

   it's performance benchmarks are certainly going

   to be different than an LR3.  If the nuisance

   trips go away with THAT regulator, then there

   is reason to investigate the LR-3 more closely.

   If they continue, then the difficulty will be

   have root cause in features found elsewhere.

   Bob . . .    [quote][b]

donjohnston

Joined: 13 Dec 2009
Posts: 231

Posted: Sun Jun 28, 2015 10:21 am Post subject: Re: Alternator problem?

 	  Quote: 	
		  I suggest that instead of pulling the alternator, that you replace the voltage regulator with a generic Ford VR166 or equivalent. There is a list in Bob's book. The over-voltage and low voltage features of the LR3 are not needed in your application if the VP-X provides over-voltage and the EFIS gives low voltage warning.



An excellent experiment. If the VR-166 style

regulators are presently fitted with OV protection,

it's performance benchmarks are certainly going

to be different than an LR3. If the nuisance

trips go away with THAT regulator, then there

is reason to investigate the LR-3 more closely.

If they continue, then the difficulty will be

have root cause in features found elsewhere. 	
 



I thought that voltage regulators were voltage specific?  Are these generic VR's available in 28v versions?

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Jun 28, 2015 11:53 am Post subject: Alternator problem?

 	  Quote: 	
		  I thought that voltage regulators were voltage specific?  Are these generic VR's available in 28v versions? 	


   OOPS!  You caught us with our perceptions down . . .

   yes, the VR166 is 14v only. Scratch that idea.



 

   Bob . . .    [quote][b]

user9253

Joined: 28 Mar 2008
Posts: 1908
Location: Riley TWP Michigan

Posted: Sun Jun 28, 2015 12:34 pm Post subject: Re: Alternator problem?

 	  Quote: 	
		  I thought that voltage regulators were voltage specific? Are these generic VR's available in 28v versions? 	


Oops, my mistake.  I forgot about the 28 volt system.  I do not know of any generic 28 volt regulators.

_________________
Joe Gores

ceengland7(at)gmail.com
Guest

Posted: Sun Jun 28, 2015 1:30 pm Post subject: Alternator problem?

On 6/28/2015 3:34 PM, user9253 wrote:

 	  Quote: 	
		   

> I thought that voltage regulators were voltage specific? Are these generic VR's available in 28v versions?

 Oops, my mistake.  I forgot about the 28 volt system.  I do not know of any generic 28 volt regulators.



 --------

 Joe Gores

They are out there; just not so easy to find. 1st hit I got:
	


http://www.ebay.com/itm/NEW-24-VOLT-POSITIVE-OR-NEGITIVE-GROUND-REGULATOR-D2152-FARM-INDUSTRIAL-/151618159386

user9253

Joined: 28 Mar 2008
Posts: 1908
Location: Riley TWP Michigan

Posted: Sun Jun 28, 2015 6:42 pm Post subject: Re: Alternator problem?

24 volt Voltage regulator, eBay item number:151689173831, is only $10.  Has anyone ever tried to adapt an internal voltage regulator for external use?

Joe

_________________
Joe Gores

ceengland7(at)gmail.com
Guest

Posted: Sun Jun 28, 2015 7:04 pm Post subject: Alternator problem?

On 6/28/2015 9:42 PM, user9253 wrote:

 	  Quote: 	
		   



 24 volt Voltage regulator, eBay item number:151689173831, is only $10.  Has anyone ever tried to adapt an internal voltage regulator for external use?

 Joe



 --------

 Joe Gores

I wondered about that, as well. Shouldn't be too big a deal for someone 
	


handy with a soldering iron.



Charlie

rnjcurtis(at)charter.net
Guest

Posted: Mon Jun 29, 2015 4:07 am Post subject: Alternator problem?

I converted a Denso alternator to external using the instructions published on the EAA site.  It is not difficult, but takes a bit of time.  

Roger

Sent from: YOGA TABLET 10 HD+

Charlie England <ceengland7(at)gmail.com> wrote:

 	  Quote: 	

On 6/28/2015 9:42 PM, user9253 wrote:

> 

>

> 24 volt Voltage regulator, eBay item number:151689173831, is only $10.  Has anyone ever tried to adapt an internal voltage regulator for external use?

> Joe

>

> --------

> Joe Gores

I wondered about that, as well. Shouldn't be too big a deal for someone 

handy with a soldering iron.

Charlie

rnjcurtis(at)charter.net
Guest

Posted: Mon Jun 29, 2015 4:34 am Post subject: Alternator problem?

In rereading the posts, It appears that the conversation was referring to removing an internal regulator  and using it externally.  I don't know of anyone doing this.



Roger



Sent from: YOGA TABLET 10 HD+



rnjcurtis <rnjcurtis(at)charter.net> wrote:






I converted a Denso alternator to external using the instructions published on the EAA site.  It is not difficult, but takes a bit of time.  



Roger

ceengland7(at)gmail.com
Guest

Posted: Mon Jun 29, 2015 4:40 am Post subject: Alternator problem?

I think Joe is referring to actually using the regulator that's made for internal regulation as an external regulator. A bit more involved than adapting an external regulator to a '1-wire' alternator (but not a lot more).



Charlie

On Mon, Jun 29, 2015 at 7:04 AM, rnjcurtis <rnjcurtis(at)charter.net (rnjcurtis(at)charter.net)> wrote:

[quote]--> AeroElectric-List message posted by: rnjcurtis <rnjcurtis(at)charter.net (rnjcurtis(at)charter.net)>

 

 I converted a Denso alternator to external using the instructions published on the EAA site.Â  It is not difficult, but takes a bit of time.

 

 Roger

 

 

 

 Sent from: YOGA TABLET 10 HD+

 

 Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)> wrote:

 

 >--> AeroElectric-List message posted by: Charlie England <ceengland7(at)gmail.com (ceengland7(at)gmail.com)>

 >

 >On 6/28/2015 9:42 PM, user9253 wrote:

 >> --> AeroElectric-List message posted by: "user9253" <fransew(at)gmail.com (fransew(at)gmail.com)>

 >>

 >> 24 volt Voltage regulator, eBay item number:151689173831, is only $10.Â  Has anyone ever tried to adapt an internal voltage regulator for external use?

 >> Joe

 >>

 >> --------

 >> Joe Gores

 >I wondered about that, as well. Shouldn't be too big a deal for someone

 >handy with a soldering iron.

 >

 >Charlie

 >

 >

 >

 >

 

 

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 [b]

donjohnston

Joined: 13 Dec 2009
Posts: 231

Posted: Mon Jun 29, 2015 4:45 am Post subject: Re: Alternator problem?

I appreciate the suggestions.  But I'm not sure if trying to MacGuyver a voltage regulator is good way to troubleshoot my current issue.   



Vertical Power has offered to bench check the VP-X but removing it won't be the easiest thing and I'm looking at a 10-day turnaround. 



So buying a new LR3C-28 at $198 may be a relatively easy and timely (although not very cost effective) step.  If it turns out not to be the VR, I guess I'll have a spare.  



At that point, it would most likely be the VP-X and then I could send that out.

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Jun 29, 2015 5:06 am Post subject: Alternator problem?

At 07:31 AM 6/29/2015, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: rnjcurtis <rnjcurtis(at)charter.net>



 In rereading the posts, It appears that the conversation was referring to removing an internal regulator  and using it externally.  I don't know of anyone doing this. 	


  There was an article, I think in Sport Aviation

  some years ago about making electrical connections

  to a dis-mounted replacement for an I-R alternator

  regulator for use as a stand-alone external

  regulator.



  A straight-forward task . . . sometimes. Some

  internal regulators utilize and AC voltage sense

  path connected to on of the windings. Without

  specific knowledge of this feature, the

  activity is problematic. The article spoke

  to a particular OEM part that was not so

  equipped . . . finding one in 28v and knowing

  it's pedigree would be difficult.



 

 

   Bob . . .    [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Mon Jun 29, 2015 6:53 am Post subject: Alternator problem?

At 07:45 AM 6/29/2015, you wrote:

  	  Quote: 	
		  --> AeroElectric-List message posted by: "donjohnston" <don(at)velocity-xl.com>



 I appreciate the suggestions.  But I'm not sure if trying to MacGuyver a voltage regulator is good way to troubleshoot my current issue.  [Laughing] 



 Vertical Power has offered to bench check the VP-X but removing it won't be the easiest thing and I'm looking at a 10-day turnaround. 



 So buying a new LR3C-28 at $198 may be a relatively easy and timely (although not very cost effective) step.  If it turns out not to be the VR, I guess I'll have a spare.  



 At that point, it would most likely be the VP-X and then I could send that out. 	


   It's all most a given that both the LR3 and the

   VPX will bench check okay . . . as would the

   alternator. Everything is probably performing

   as their designers intended.



   Let's do the filter thingy first. Need a mailing

   address.



 

 

   Bob . . .    [quote][b]

donjohnston

Joined: 13 Dec 2009
Posts: 231

Posted: Mon Jun 29, 2015 7:54 am Post subject: Re: Alternator problem?

Bob,



I couldn't figure out how to do a private message here. So I sent you an email yesterday with my mailing address. 



-Don



Edit: Bob,  I figured it out.  Sent you a PM.

Last edited by donjohnston on Tue Jun 30, 2015 3:37 am; edited 1 time in total

ceengland7(at)gmail.com
Guest

Posted: Mon Jun 29, 2015 9:03 am Post subject: Alternator problem?

Cheap troubleshooting by substitution (only), as implied by the previous suggestion of using a COTS Ford regulator to substitute for the existing unit (not possible due to existing unit being 28v instead of 14v).Â 



Turning alternators on/off is a completely different issue, and begs the question: Why?

On Mon, Jun 29, 2015 at 7:47 AM,  <rnjcurtis(at)charter.net (rnjcurtis(at)charter.net)> wrote:

[quote]      



I think Joe is referring to actually using the regulator that's made for internal regulation as an external regulator. A bit more involved than adapting an external regulator to a '1-wire' alternator (but not a lot more).

 	  Quote: 	
		  In doing this, wouldnâ€™t one be just moving the problems that have been discussed in great detail, of why we should not use internally regulated alternators.Â  The internal regulators do not react kindly to turning the alternator on and off.

Roger

	
 



 

  [b]

nuckolls.bob(at)aeroelect
Guest

Posted: Tue Jun 30, 2015 7:14 am Post subject: Alternator problem?

 	  Quote: 	
		     In doing this, wouldnâ€™t one be just moving the problems that have been discussed in great detail, of why we should not use internally regulated alternators.Â  The internal regulators do not react kindly to turning the alternator on and off. 	
  



   It's not a matter of 'not taking kindly' . . . its the

   conditions surrounding a failure modes. Off the shelf, internally

   regulated alternators have a runaway failure mode wherein the

   alternator CANNOT be shut off from outside. This is why

   some folks remove the built in regulator (B&C) and others

   wire around the regulator (Plane-Power) to effect positive

   external control of field excitation for the purpose of

   turning it ON or OFF at will, or shutting it down if

   the regulator goes TU.



   A myth commonly circulated throughout the vehicular

   DC power systems world is that it is undesirable,

   dangerous, deleterious, or (as has been articulated

   here on the List) just plain stupid to turn an

   operating alternator ON and OFF at will. It's

   a well circulated, overly fertilized myth easily

   demonstrated to be horse-pucky.  The desirability

   for and effects of random or purposeful control

   of an alternator at will are completely benign

   to the alternator and equipment it powers.



   But if the regulator wanders into the weeds, 

   you gotta have a method to turn the thing OFF

   (or disconnect it from the airplane) in a timely

   fashion while minimizing smoke and flames.



 

   Bob . . .    [quote][b]

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