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sportav8r(at)gmail.com
Guest

Posted: Fri Oct 20, 2006 4:29 pm Post subject: automotive alternator question - OT

Just when I thought I knew a little something from building airplanes

and hanging out here for five years or so...



Yesterday my wife was driving my son's 99 Hyundai when warning lights

began to appear one by one- battery, emergency brake, air bag; then

the speedometer and tach indications went to zero, and finally the

engine itself quit running.  She phoned me at the office, and I told

her that she had just described a classic alternator failure with

subsequent run-down of the remaining energy in the battery.  We

confirmed that the alternator belt had not broken, but there was

little to do but call for help.  Help arrived, gave her a jump start;

she was able to drive part way to the repair shop when the same

sequence repeated itself.  The second jump start got her the rest of

the way to the repair bay.



We called today, expecting the bill to be large, but it was under

$100.  When I got there to talk to the mechanic, I told him I had

expected an alternator replacement to be part of the plan.  He assured

me that only the battery was faulty, and that the alternator was

"putting out 14.3" so all was well.  I asked how the car could die

electrically when the engine was running, and he gave me a sympathetic

look and began to explain how generators put out direct current, but

the new-fangled alternators put out _alternating current_ and they

need a battery to keep them excited.  I pretended to take it all in

and thanked him, paid the bill, and told the wife to ride home close

behind me, because with an ailing alternator, I likely had only the

joules in the battery to make the half-hour trip in the dark.  I did

my best to keep the electrical loads light, as if running on the e-bus

in the scud 



To my surprise, the alternator indeed seems to be charging normally,

and the new battery installation seems to have mysteriously fixed

things.



Now, I know there is no way that a battery continually feeds current

into an alternator to keep it going, else charging the battery from

the alternator would be a losing proposition.  And I certianly hope

that there is no way a dead battery is going to somehow take out my

dual alternator Z-13/8 architecture, but I cannot reconcile that hope

with what seems to have happened to my car electrical system here.

Tell me I'm not crazy, and that it doesn't take a battery to keep an

alternator alive once excited (the same battery that minutes before

cranked the engine for starting), that the battery is only there for

filtering the 3-phase rectified DC when in cruise mode, and I'll

believe you.  But I'll still wonder what happened to the car

yesterday...



-Bill B

echristley(at)nc.rr.com
Guest

Posted: Fri Oct 20, 2006 7:39 pm Post subject: automotive alternator question - OT

Bill Boyd wrote:

 	  Quote: 	
		   But I'll still wonder what happened to the car

 yesterday...



Bill, does the alternators B-lead connect at the battery post?  I may be 
	


very wrong, but I seem to recall an old Nissan truck I owned being wired 

that way.  If it is the case, a dirty battery cable termination would 

give exactly the symptoms you describe, and would be cured by replacing 

the battery (the connector gets jostled around, knocking out the 

corrosion long enough to make it home).

FLYaDIVE(at)aol.com
Guest

Posted: Sat Oct 21, 2006 3:58 am Post subject: automotive alternator question - OT

In a message dated 10/20/2006 8:33:36 PM Eastern Standard Time, sportav8r(at)gmail.com writes:

  	  Quote: 	
		  Now, I know there is no way that a battery continually feeds current

into an alternator to keep it going, else charging the battery from

the alternator would be a losing proposition.  And I certianly hope

that there is no way a dead battery is going to somehow take out my

dual alternator Z-13/8 architecture, but I cannot reconcile that hope

with what seems to have happened to my car electrical system here.

Tell me I'm not crazy, and that it doesn't take a battery to keep an

alternator alive once excited (the same battery that minutes before

cranked the engine for starting), that the battery is only there for

filtering the 3-phase rectified DC when in cruise mode, and I'll

believe you.  But I'll still wonder what happened to the car

yesterday...



-Bill B 	


 ===================================

 Bill:

  

 There are MANY new things happening to cars today.  As soon as you mentioned HYUNDAI I knew what your problem was... IS.

  

 It is NOT solved yet.  The new battery will keep the car going for a few more weeks but the problem MAY surely pop up again.  The battery was border line due to the problem and did require replacing, maybe not immediately.  Still the new battery is a move in the right direction.  

  

 You did not mention the year and model of the Hyundai.

  

 When I said new things happening to cars; there is a different way of utilizing a car's charging system today.  The alternator is still the same and the voltage regulator is still the same but with car computer systems and trying to squeeze more HP from a smaller engine there is a new twist.  The computer takes the alternator TOTALLY out of the electrical system and it does this for more of a DOWN TIME on the duty cycle.  An alternator uses between 2 to 5 HP during operation.  By taking the alternator out of the system you return that HP so it can be sent to the wheels and use less gas.  Now, not all computerized cars do this ... what year and model is yours?

  

 Also, newer cars with an alternator CAN run without a battery.  NOT for a very long time ... It is know as the Get Home Mode.  In the OLD days with Generators this was the NORM.  But, just like in a plane's system a GOOD battery is required to let the alternator have an output.  If the battery dies there is NO voltage for the alternators field ... ergo ... No alternator output.  New cars are similar but utilize a large value capacitor to TRY to keep the alternator running.  The "TC"  Time Constant is slow so IF you shed load it will TRY to get you home.  No, I did not design this system so I don't know any more about it.

  

 I have a Hyundai and I have had the same problem and here is a hit.  What is it, that I bitch about on planes all the time, that always starts the same old deadhead thought patterns and emails?  Well, that is exactly what is wrong with your car.  Repair Time - 15 minutes.

  

  

  

  

 Barry

"Chop'd Liver"



"Show them the first time, correct them the second time, kick them the third 

time." 

Yamashiada

sportav8r(at)gmail.com
Guest

Posted: Sat Oct 21, 2006 4:57 am Post subject: automotive alternator question - OT

Thanks, Barry, Ernest,



The car is  99 Sonata, on its second engine but first alternator.

Wife reports the pos battery terminal was very corroded when she

looked under the hood before the repair.  Perhaps a sigificant finding

and the whole explanation.



I still struggle to understand how an alternator can carry ship;'s

loads, and recharge the battery after cranking, if the computer

disconnects it in cruise, as well as how an alternator that has been

excited and spun up, making power, can fail to maintain its own field

current even in the absence of a battery.  This characterisitc, if

true, is an annoyance in a car; it might be an Achilles heel in a

Z-architecture electrical system, if it means that a dead or even

corroded battery could take out battery and alternator with a most no

warning.  I really want to understand this potential failure mode.



Not meaning to offend anyone, I hope the designer of the

Z-architectures will himself weigh in and elucidate me.  Meanwhile, I

shall pop the hood and inspect the repairs myself in the light of day,

with VOM in hand.  Bob...?



-Bill B



On 10/21/06, FLYaDIVE(at)aol.com <FLYaDIVE(at)aol.com> wrote:

 	  Quote: 	
		  

 In a message dated 10/20/2006 8:33:36 PM Eastern Standard Time,

 sportav8r(at)gmail.com writes:

 Now, I know there is no way that a battery continually feeds current

 into an alternator to keep it going, else charging the battery from

 the alternator would be a losing proposition.  And I certianly hope

 that there is no way a dead battery is going to somehow take out my

 dual alternator Z-13/8 architecture, but I cannot reconcile that hope

 with what seems to have happened to my car electrical system here.

 Tell me I'm not crazy, and that it doesn't take a battery to keep an

 alternator alive once excited (the same battery that minutes before

 cranked the engine for starting), that the battery is only there for

 filtering the 3-phase rectified DC when in cruise mode, and I'll

 believe you.  But I'll still wonder what happened to the car

 yesterday...



 -Bill B

 ===================================

 Bill:



 There are MANY new things happening to cars today.  As soon as you mentioned

 HYUNDAI I knew what your problem was... IS.



 It is NOT solved yet.  The new battery will keep the car going for a few

 more weeks but the problem MAY surely pop up again.  The battery was border

 line due to the problem and did require replacing, maybe not immediately.

 Still the new battery is a move in the right direction.



 You did not mention the year and model of the Hyundai.



 When I said new things happening to cars; there is a different way of

 utilizing a car's charging system today.  The alternator is still the same

 and the voltage regulator is still the same but with car computer systems

 and trying to squeeze more HP from a smaller engine there is a new twist.

 The computer takes the alternator TOTALLY out of the electrical system and

 it does this for more of a DOWN TIME on the duty cycle.  An alternator uses

 between 2 to 5 HP during operation.  By taking the alternator out of the

 system you return that HP so it can be sent to the wheels and use less gas.

 Now, not all computerized cars do this ... what year and model is yours?



 Also, newer cars with an alternator CAN run without a battery.  NOT for a

 very long time ... It is know as the Get Home Mode.  In the OLD days with

 Generators this was the NORM.  But, just like in a plane's system a GOOD

 battery is required to let the alternator have an output.  If the battery

 dies there is NO voltage for the alternators field ... ergo ... No

 alternator output.  New cars are similar but utilize a large value capacitor

 to TRY to keep the alternator running.  The "TC"  Time Constant is slow so

 IF you shed load it will TRY to get you home.  No, I did not design this

 system so I don't know any more about it.



 I have a Hyundai and I have had the same problem and here is a hit.  What is

 it, that I bitch about on planes all the time, that always starts the same

 old deadhead thought patterns and emails?  Well, that is exactly what is

 wrong with your car.  Repair Time - 15 minutes.





 Barry

 "Chop'd Liver"



 "Show them the first time, correct them the second time, kick them the third

 time."

 Yamashiada

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

lists(at)stevet.net
Guest

Posted: Sat Oct 21, 2006 5:45 am Post subject: automotive alternator question - OT

First thing - you pay attention to those kind of things when you do  

your routine maintenance.  Second, this is another good reason for  

Bob's advice to replace batteries at every annual, or, with dual  

battery systems, dump #2 battery, rotate #1 into #2, and replace #1  

every annual.  The one habit we get into with cars is to try and milk  

every ounce of battery life we can and wait to replace them until  

they are dead in the water.  There are many inexpensive battery  

options out there where you can replace every annual and not worry  

about it.



Best Regards,



Steve Thomas



____________________________________________________________________

On Oct 21, 2006, at 5:55 AM, Bill Boyd wrote:



 	  Quote: 	
		   

 <sportav8r(at)gmail.com>



 Thanks, Barry, Ernest,



 The car is  99 Sonata, on its second engine but first alternator.

 Wife reports the pos battery terminal was very corroded when she

 looked under the hood before the repair.  Perhaps a sigificant finding

 and the whole explanation.



 I still struggle to understand how an alternator can carry ship;'s

 loads, and recharge the battery after cranking, if the computer

 disconnects it in cruise, as well as how an alternator that has been

 excited and spun up, making power, can fail to maintain its own field

 current even in the absence of a battery.  This characterisitc, if

 true, is an annoyance in a car; it might be an Achilles heel in a

 Z-architecture electrical system, if it means that a dead or even

 corroded battery could take out battery and alternator with a most no

 warning.  I really want to understand this potential failure mode.



 Not meaning to offend anyone, I hope the designer of the

 Z-architectures will himself weigh in and elucidate me.  Meanwhile, I

 shall pop the hood and inspect the repairs myself in the light of day,

 with VOM in hand.  Bob...?



 -Bill B



 On 10/21/06, FLYaDIVE(at)aol.com <FLYaDIVE(at)aol.com> wrote:

>

> In a message dated 10/20/2006 8:33:36 PM Eastern Standard Time,

> sportav8r(at)gmail.com writes:

> Now, I know there is no way that a battery continually feeds current

> into an alternator to keep it going, else charging the battery from

> the alternator would be a losing proposition.  And I certianly hope

> that there is no way a dead battery is going to somehow take out my

> dual alternator Z-13/8 architecture, but I cannot reconcile that hope

> with what seems to have happened to my car electrical system here.

> Tell me I'm not crazy, and that it doesn't take a battery to keep an

> alternator alive once excited (the same battery that minutes before

> cranked the engine for starting), that the battery is only there for

> filtering the 3-phase rectified DC when in cruise mode, and I'll

> believe you.  But I'll still wonder what happened to the car

> yesterday...

>

> -Bill B

> ===================================

> Bill:

>

> There are MANY new things happening to cars today.  As soon as you  

> mentioned

> HYUNDAI I knew what your problem was... IS.

>

> It is NOT solved yet.  The new battery will keep the car going for  

> a few

> more weeks but the problem MAY surely pop up again.  The battery  

> was border

> line due to the problem and did require replacing, maybe not  

> immediately.

> Still the new battery is a move in the right direction.

>

> You did not mention the year and model of the Hyundai.

>

> When I said new things happening to cars; there is a different way of

> utilizing a car's charging system today.  The alternator is still  

> the same

> and the voltage regulator is still the same but with car computer  

> systems

> and trying to squeeze more HP from a smaller engine there is a new  

> twist.

> The computer takes the alternator TOTALLY out of the electrical  

> system and

> it does this for more of a DOWN TIME on the duty cycle.  An  

> alternator uses

> between 2 to 5 HP during operation.  By taking the alternator out  

> of the

> system you return that HP so it can be sent to the wheels and use  

> less gas.

> Now, not all computerized cars do this ... what year and model is  

> yours?

>

> Also, newer cars with an alternator CAN run without a battery.   

> NOT for a

> very long time ... It is know as the Get Home Mode.  In the OLD  

> days with

> Generators this was the NORM.  But, just like in a plane's system  

> a GOOD

> battery is required to let the alternator have an output.  If the  

> battery

> dies there is NO voltage for the alternators field ... ergo ... No

> alternator output.  New cars are similar but utilize a large value  

> capacitor

> to TRY to keep the alternator running.  The "TC"  Time Constant is  

> slow so

> IF you shed load it will TRY to get you home.  No, I did not  

> design this

> system so I don't know any more about it.

>

> I have a Hyundai and I have had the same problem and here is a  

> hit.  What is

> it, that I bitch about on planes all the time, that always starts  

> the same

> old deadhead thought patterns and emails?  Well, that is exactly  

> what is

> wrong with your car.  Repair Time - 15 minutes.

>

>

> Barry

> "Chop'd Liver"

>

> "Show them the first time, correct them the second time, kick them  

> the third

> time."

> Yamashiada

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

>

khorton01(at)rogers.com
Guest

Posted: Sat Oct 21, 2006 6:00 am Post subject: automotive alternator question - OT

On 21 Oct 2006, at 08:55, Bill Boyd wrote:



 	  Quote: 	
		   

 <sportav8r(at)gmail.com>



 Thanks, Barry, Ernest,



 The car is  99 Sonata, on its second engine but first alternator.

 Wife reports the pos battery terminal was very corroded when she

 looked under the hood before the repair.  Perhaps a sigificant finding

 and the whole explanation.



 I still struggle to understand how an alternator can carry ship;'s

 loads, and recharge the battery after cranking, if the computer

 disconnects it in cruise, as well as how an alternator that has been

 excited and spun up, making power, can fail to maintain its own field

 current even in the absence of a battery.  This characterisitc, if

 true, is an annoyance in a car; it might be an Achilles heel in a

 Z-architecture electrical system, if it means that a dead or even

 corroded battery could take out battery and alternator with a most no

 warning.  I really want to understand this potential failure mode.



 Not meaning to offend anyone, I hope the designer of the

 Z-architectures will himself weigh in and elucidate me.  Meanwhile, I

 shall pop the hood and inspect the repairs myself in the light of day,

 with VOM in hand.  Bob...?


	


It would be interesting to know where the field current comes from,  

and where the various automotive systems are getting their power  

(i.e. lights, fuel pumps, EFI, etc).



If the "smart" voltage regulator actually shuts the alternator down  

during some periods, and the alternator had become electrically  

disconnected from the battery due to corrosion on the battery post,  

and the field current was getting its power from the alternator  

output, then it is plausible that there would be no way to start the  

alternator back up again.



But, how were the other systems able to get the power they needed?   

Will the other systems run at lower voltages than is required to  

start the alternator back up again?



Kevin Horton         RV-8 (finishing kit)

Ottawa, Canada

http://www.kilohotel.com/rv8

sportav8r(at)gmail.com
Guest

Posted: Sat Oct 21, 2006 3:45 pm Post subject: automotive alternator question - OT

Follow-up:



My son took the car this morning while I was out flying around, and

before I could check the charging system with a DVM to verify

alternator output.  The ensuing events restored my confidence in the

laws of physics and what understanding I thought I had in how

alternators work (smart regulators being another story, I will

concede).  The call to come give him a jump start-came about dusk.  We

drove the car a few blocks to the repair garage in town, where it will

remain until a new alternator (one that makes current  is

installed.



I hate to flog a new battery into deep discharge the first day I own

it, but at least this time it happened near home, and just as I

thought it would/should with an alternator that almost had to be

inoperative, given the scenario yesterday.  Restores my faith in my

understanding of electrical systems, but not in shade tree mechanics.



Probably nothing to see here, folks... just move along... nothing to see here...



Sorry to clog list bandwidth with a problem like this, but the guy

really had me doubting my basic understanding of alternators and

therefore the integrity of my OBAM charging system as well.



-Bill B



On 10/21/06, Kevin Horton <khorton01(at)rogers.com> wrote:

 	  Quote: 	
		   



 On 21 Oct 2006, at 08:55, Bill Boyd wrote:



 > 

 > <sportav8r(at)gmail.com>

 >

 > Thanks, Barry, Ernest,

 >

 > The car is  99 Sonata, on its second engine but first alternator.

 > Wife reports the pos battery terminal was very corroded when she

 > looked under the hood before the repair.  Perhaps a sigificant finding

 > and the whole explanation.

 >

 > I still struggle to understand how an alternator can carry ship;'s

 > loads, and recharge the battery after cranking, if the computer

 > disconnects it in cruise, as well as how an alternator that has been

 > excited and spun up, making power, can fail to maintain its own field

 > current even in the absence of a battery.  This characterisitc, if

 > true, is an annoyance in a car; it might be an Achilles heel in a

 > Z-architecture electrical system, if it means that a dead or even

 > corroded battery could take out battery and alternator with a most no

 > warning.  I really want to understand this potential failure mode.

 >

 > Not meaning to offend anyone, I hope the designer of the

 > Z-architectures will himself weigh in and elucidate me.  Meanwhile, I

 > shall pop the hood and inspect the repairs myself in the light of day,

 > with VOM in hand.  Bob...?



 It would be interesting to know where the field current comes from,

 and where the various automotive systems are getting their power

 (i.e. lights, fuel pumps, EFI, etc).



 If the "smart" voltage regulator actually shuts the alternator down

 during some periods, and the alternator had become electrically

 disconnected from the battery due to corrosion on the battery post,

 and the field current was getting its power from the alternator

 output, then it is plausible that there would be no way to start the

 alternator back up again.



 But, how were the other systems able to get the power they needed?

 Will the other systems run at lower voltages than is required to

 start the alternator back up again?



 Kevin Horton         RV-8 (finishing kit)

 Ottawa, Canada

 http://www.kilohotel.com/rv8

FLYaDIVE(at)aol.com
Guest

Posted: Sun Oct 22, 2006 3:21 am Post subject: automotive alternator question - OT

In a message dated 10/21/2006 7:48:22 PM Eastern Standard Time, sportav8r(at)gmail.com writes:

  	  Quote: 	
		  .  The call to come give him a jump start-came about dusk.  We

drove the car a few blocks to the repair garage in town, where it will

remain until a new alternator (one that makes current  is

installed. 	


 =============================================

 Kevin:

  

 The problem is NOT the alternator!

  

 Your alternator is in PERFECT CONDITION, it is WORKING.

  

  

 Barry

"Chop'd Liver"



"Show them the first time, correct them the second time, kick them the third 

time." 

Yamashiada

FLYaDIVE(at)aol.com
Guest

Posted: Sun Oct 22, 2006 3:28 am Post subject: automotive alternator question - OT

In a message dated 10/21/2006 9:48:10 AM Eastern Standard Time, lists(at)stevet.net writes:

  	  Quote: 	
		  this is another good reason for  

Bob's advice to replace batteries at every annual 	


 ============================

 Is it REALLY you Bob that started this Wives Tail?  I would say Old Wives Tail, but you are not that old yet.

  

  

 Barry

"Chop'd Liver"



"Show them the first time, correct them the second time, kick them the third 

time." 

Yamashiada

sportav8r(at)gmail.com
Guest

Posted: Sun Oct 22, 2006 5:09 am Post subject: automotive alternator question - OT

Barry,



You are welcome to email me direct with your theory on what, besides

an alternator malfunction, will allow two batteries in 2 days to be

sucked dry during operation of the vehicle.  This has reached the

point where it is of dubious aircraft electrical relevance and should

be taken off-list.



And if you'll call me "Bill" instead of "Kevin," I'll resist the

inexplicable urge to call you "George" or Paul" 



-Bill



On 10/22/06, FLYaDIVE(at)aol.com <FLYaDIVE(at)aol.com> wrote:

 	  Quote: 	
		  

 In a message dated 10/21/2006 7:48:22 PM Eastern Standard Time,

 sportav8r(at)gmail.com writes:

 .  The call to come give him a jump start-came about dusk.  We

 drove the car a few blocks to the repair garage in town, where it will

 remain until a new alternator (one that makes current  is

 installed.

 =============================================

 Kevin:



 The problem is NOT the alternator!



 Your alternator is in PERFECT CONDITION, it is WORKING.

 Barry

 "Chop'd Liver"



 "Show them the first time, correct them the second time, kick them the third

 time."

 Yamashiada



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

sportav8r(at)gmail.com
Guest

Posted: Sun Oct 22, 2006 5:12 am Post subject: automotive alternator question - OT

If I recall correctly, Bob advocates periodic battery replacement (TWO

year interval) in lieu of more involved capacity testing, which  some

of us find less convenient.  I for one have found plenty of use for

the Odyssey "pulls" in my lawn tractors, emergency home generator, and

amateur radio applications.  I find his advice eminently practical for

my purposes, and will continue to follow it.



-Bill B



On 10/22/06, FLYaDIVE(at)aol.com <FLYaDIVE(at)aol.com> wrote:

 	  Quote: 	
		  

 In a message dated 10/21/2006 9:48:10 AM Eastern Standard Time,

 lists(at)stevet.net writes:

 this is another good reason for

 Bob's advice to replace batteries at every annual

 ============================

 Is it REALLY you Bob that started this Wives Tail?  I would say Old Wives

 Tail, but you are not that old yet.

 Barry

 "Chop'd Liver"



 "Show them the first time, correct them the second time, kick them the third

 time."

 Yamashiada

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

oldbob(at)beechowners.com
Guest

Posted: Sun Oct 22, 2006 6:03 am Post subject: automotive alternator question - OT

Good Morning Yamashiada, or Chopped Liver, or Kevin,

Or

Bill or Whomever,



Why not keep the discussion on the Aero Electric list.

Those of us who have absolutely no electrical

knowledge are puzzled by the problem. 



Who knows, we MAY learn something that WILL help us in

our aeronautical endeavors.



Very Sincerely Interested,



Old Bob



--- Bill Boyd <sportav8r(at)gmail.com> wrote:



 	  Quote: 	
		   

 <sportav8r(at)gmail.com>

 

 Barry,

 

 You are welcome to email me direct with your theory

 on what, besides

 an alternator malfunction, will allow two batteries

 in 2 days to be

 sucked dry during operation of the vehicle.  This

 has reached the

 point where it is of dubious aircraft electrical

 relevance and should

 be taken off-list.

 

 And if you'll call me "Bill" instead of "Kevin,"

 I'll resist the

 inexplicable urge to call you "George" or Paul" 

 

 -Bill

 

 On 10/22/06, FLYaDIVE(at)aol.com <FLYaDIVE(at)aol.com>

 wrote:

 >

 >

 >

 > In a message dated 10/21/2006 7:48:22 PM Eastern

 Standard Time,

 > sportav8r(at)gmail.com writes:

 > .  The call to come give him a jump start-came

 about dusk.  We

 > drove the car a few blocks to the repair garage in

 town, where it will

 > remain until a new alternator (one that makes

 current  is

 > installed.

 > =============================================

 > Kevin:

 >

 > The problem is NOT the alternator!

 >

 > Your alternator is in PERFECT CONDITION, it is

 WORKING.

 >

 >

 > Barry

 > "Chop'd Liver"

 >

 > "Show them the first time, correct them the second

 time, kick them the third

 > time."

 > Yamashiada

 >

 >

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

 >

 >

 >

 



 browse

 Subscriptions page,

 FAQ,

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



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 Admin.

nuckollsr(at)cox.net
Guest

Posted: Sun Oct 22, 2006 7:22 am Post subject: automotive alternator question - OT

At 07:57 AM 10/21/2006 -0400, you wrote:



 	  Quote: 	
		  In a message dated 10/20/2006 8:33:36 PM Eastern Standard Time, 

sportav8r(at)gmail.com writes:

Now, I know there is no way that a battery continually feeds current

into an alternator to keep it going, else charging the battery from

the alternator would be a losing proposition.


	


    Alternators generally need a modicum of start-up voltage to

    come alive. Once up and running, they'll continue to put

    out useful energy within limits (1) hit them with a strong

    inrush current and they may "stall" and (2) without a battery

    across the b-lead output, the quality of delivered energy

    is compromised with combinations of additional noise and/or

    loss of voltage regulation stability.

 	  Quote: 	
		    And I certianly hope

that there is no way a dead battery is going to somehow take out my

dual alternator Z-13/8 architecture, but I cannot reconcile that hope

with what seems to have happened to my car electrical system here.


	


    There's no way a battery or lack thereof will kill

    a good alternator.

 	  Quote: 	
		  Tell me I'm not crazy, and that it doesn't take a battery to keep an

alternator alive once excited (the same battery that minutes before

cranked the engine for starting), that the battery is only there for

filtering the 3-phase rectified DC when in cruise mode, and I'll

believe you.  But I'll still wonder what happened to the car

yesterday...


	




    The troubleshooting problem is a transfer of energy

    study. And many times, what appears to be "obvious"

    is lacking in data and peripheral information to make

    an accurate diagnosis. For example, I spent three days

    this week working on a flickering light problem on a

    $gazillion$ bizjet wherein there was a strong consensus

    that adding some big fat capacitors to reduce the

    intensity of a bus voltage perturbation would reduce

    the apparent intensity of the flicker. Spent $700 of

    the boss's money on some automotive super-caps (used

    in those ear-pounding sound systems that are misguided

    progeny are so fond of). Eureka! 1 Farad of capacity

    across the 50A thumper did indeed reduce bus perturbations

    from 4 volts pk-pk to 1 volt pk-pk. But the flickering

    was WORSE!



    Seems the eye was influenced more by duration than by

    gross intensity when observing 25 mS wide variations

    in light output. Even tho the intensity was reduced

    by 75%, the width of the perturbation increased by

    2x to 50 mS. Who wuda thunk it?



    The point is that energy does not go wandering about

    like a 4-year old in a toy store. It moves based on

    predictable pathways and produces varying effects based

    on how the energy is dissipated, measured or perceived.



 	  Quote: 	
		  -Bill B



===================================

Bill:



There are MANY new things happening to cars today.  As soon as you 

mentioned HYUNDAI I knew what your problem was... IS.



It is NOT solved yet.  The new battery will keep the car going for a few 

more weeks but the problem MAY surely pop up again.  The battery was 

border line due to the problem and did require replacing, maybe not 

immediately.  Still the new battery is a move in the right direction.



You did not mention the year and model of the Hyundai.



When I said new things happening to cars; there is a different way of 

utilizing a car's charging system today.  The alternator is still the same 

and the voltage regulator is still the same but with car computer systems 

and trying to squeeze more HP from a smaller engine there is a new 

twist.  The computer takes the alternator TOTALLY out of the electrical 

system and it does this for more of a DOWN TIME on the duty cycle.  An 

alternator uses between 2 to 5 HP during operation.  By taking the 

alternator out of the system you return that HP so it can be sent to the 

wheels and use less gas.  Now, not all computerized cars do this ... what 

year and model is yours?


	


    Interesting. I spent about 10 minutes in a Google search

    to see if anyone on the 'net has discussed this concept and

    was unable to locate any articles that spoke of scheduling

    the car's alternator output on-the-fly.



    Can you point us to one or more sources for information on

    this control philosophy?

 	  Quote: 	
		  

Also, newer cars with an alternator CAN run without a battery.  NOT for a 

very long time ... It is know as the Get Home Mode.  In the OLD days with 

Generators this was the NORM.  But, just like in a plane's system a GOOD 

battery is required to let the alternator have an output.  If the battery 

dies there is NO voltage for the alternators field ... ergo ... No 

alternator output.  New cars are similar but utilize a large value 

capacitor to TRY to keep the alternator running.


	




    Also interesting but new to me. The physics of capacitor

    function suggest that having one on the output of an alternator

    is a functional substitute for having a battery available . . .

    hence the use of large capacitors on the output of the SD-8

    for noise reduction. But once an alternator is 'on line' why

    is there any need/value for having a capacitor support the

    alternator's field circuit when the alternator is quite

    capable of supporting its own field just as generators would

    support their own fields.

 	  Quote: 	
		     The "TC"  Time Constant is slow so IF you shed load it will TRY to get 

 you home.  No, I did not design this system so I don't know any more about it.



I have a Hyundai and I have had the same problem and here is a hit.  What 

is it, that I bitch about on planes all the time, that always starts the 

same old deadhead thought patterns and emails?  Well, that is exactly what 

is wrong with your car.  Repair Time - 15 minutes.


	


    Hmmmm . . . I'm lost. Are we talking about a bad capacitor,

    alternator or battery?  If a bad capacitor, are you suggesting

    that failure of the capacitor causes the alternator to mis-behave

    in a manner that prevents it from doing it's alternator-like

    duties in keeping the battery charged and the lights on?

    Can you offer more data on this?

    Bob . . .

nuckollsr(at)cox.net
Guest

Posted: Sun Oct 22, 2006 7:27 am Post subject: automotive alternator question - OT

At 07:27 AM 10/22/2006 -0400, you wrote:



 	  Quote: 	
		  In a message dated 10/21/2006 9:48:10 AM Eastern Standard Time, 

lists(at)stevet.net writes:

this is another good reason for

Bob's advice to replace batteries at every annual



============================

Is it REALLY you Bob that started this Wives Tail?  I would say Old Wives 

Tail, but you are not that old yet.


	




    Is is really you Barry who is personalizing this to

    a matter of my age or judgement? Before you drag

    the discussion down to this level, may I suggest

    you review the archives on the topic and offer

    us any new insights about the simple-ideas

    that support the philosophy. If one or more

    ideas is in error or have been mis-applied, we'd

    all be grateful for your re-direction.



    Bob . . .

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

      < What is so wonderful about scientific truth...is that >

      < the authority which determines whether there can be   >

      < debate or not does not reside in some fraternity of   >

      < scientists; nor is it divine. The authority rests     >

      < with experiment.                                      >

      <                            --Lawrence M. Krauss       >

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

nuckollsr(at)cox.net
Guest

Posted: Sun Oct 22, 2006 7:54 am Post subject: automotive alternator question - OT

At 08:55 AM 10/21/2006 -0400, you wrote:



 	  Quote: 	
		  



Thanks, Barry, Ernest,



The car is  99 Sonata, on its second engine but first alternator.

Wife reports the pos battery terminal was very corroded when she

looked under the hood before the repair.  Perhaps a sigificant finding

and the whole explanation.



I still struggle to understand how an alternator can carry ship;'s

loads, and recharge the battery after cranking, if the computer

disconnects it in cruise, as well as how an alternator that has been

excited and spun up, making power, can fail to maintain its own field

current even in the absence of a battery.  This characterisitc, if

true, is an annoyance in a car; it might be an Achilles heel in a

Z-architecture electrical system, if it means that a dead or even

corroded battery could take out battery and alternator with a most no

warning.  I really want to understand this potential failure mode.



Not meaning to offend anyone, I hope the designer of the

Z-architectures will himself weigh in and elucidate me.  Meanwhile, I

shall pop the hood and inspect the repairs myself in the light of day,

with VOM in hand.  Bob...?


	


    Excellent question and yes, alternators will run self excited

    sans battery with limits as discussed in another post. It was

    a recognition of those limits that prompted the e-bus philosophy.

    Should the alternator become unavailable due to main contactor

    failure and loss of the battery's stabilizing influence on alternator

    performance, there was still an alternate means by which useful

    electro-whizzies could be powered for a sweat-free continuation

    of flight to a friendly destination.



    One might still argue about gross battery reliability but I'm

    aware of no battery failures in an RG (or flooded battery)

    that could not have been mitigated by proper installation,

    operation and good PM whether one chooses to monitor battery

    capacity or replace-every-year.



    Z-13/8 with the self excitation feature adds yet another

    layer of confidence for sweat-free flying irrespective of

    the loss of any major system component.



    The discussion about the automotive system is germane to

    our deliberations but has yet to offer data from which a

    considered conclusion may be drawn. Data like schematics,

    measurements (is the battery seeing a high level of discharge

    while the key is off and all accessories shut down?), etc.



    The honorable Albert Einstein once opined, "Most of the

    fundamental ideas of science are essentially simple, and

    may, as a rule, be expressed in a language comprehensible

    to everyone."



    . . . and Lord Kelvin offered this, "When you can measure

    what you are speaking about and express it in numbers,

    you know something about it."



    The the path to understanding will not advance in useful

    ways without embracing these two philosophies and then

    doing the homework necessary to get the data.



    Bob . . .

nuckollsr(at)cox.net
Guest

Posted: Sun Oct 22, 2006 11:26 am Post subject: automotive alternator question - OT

At 07:44 PM 10/21/2006 -0400, you wrote:



 	  Quote: 	
		  



Follow-up:



My son took the car this morning while I was out flying around, and

before I could check the charging system with a DVM to verify

alternator output.  The ensuing events restored my confidence in the

laws of physics and what understanding I thought I had in how

alternators work (smart regulators being another story, I will

concede).  The call to come give him a jump start-came about dusk.  We

drove the car a few blocks to the repair garage in town, where it will

remain until a new alternator (one that makes current  is

installed.



I hate to flog a new battery into deep discharge the first day I own

it, but at least this time it happened near home, and just as I

thought it would/should with an alternator that almost had to be

inoperative, given the scenario yesterday.  Restores my faith in my

understanding of electrical systems, but not in shade tree mechanics.



Probably nothing to see here, folks... just move along... nothing to see 

here...



Sorry to clog list bandwidth with a problem like this, but the guy

really had me doubting my basic understanding of alternators and

therefore the integrity of my OBAM charging system as well.


	


   Bill,



   If you can keep the core and send it to me, I'll reimburse

   your shipping and core value expenses. I'd like to put the

   carcass under the oscilloscope as it were . . .



   Bob . . .

 	  Quote: 	
		  -Bill B



On 10/21/06, Kevin Horton <khorton01(at)rogers.com> wrote:

>

>

>On 21 Oct 2006, at 08:55, Bill Boyd wrote:

>

> > 

> > <sportav8r(at)gmail.com>

> >

> > Thanks, Barry, Ernest,

> >

> > The car is  99 Sonata, on its second engine but first alternator.

> > Wife reports the pos battery terminal was very corroded when she

> > looked under the hood before the repair.  Perhaps a sigificant finding

> > and the whole explanation.

> >

> > I still struggle to understand how an alternator can carry ship;'s

> > loads, and recharge the battery after cranking, if the computer

> > disconnects it in cruise, as well as how an alternator that has been

> > excited and spun up, making power, can fail to maintain its own field

> > current even in the absence of a battery.  This characterisitc, if

> > true, is an annoyance in a car; it might be an Achilles heel in a

> > Z-architecture electrical system, if it means that a dead or even

> > corroded battery could take out battery and alternator with a most no

> > warning.  I really want to understand this potential failure mode.

> >

> > Not meaning to offend anyone, I hope the designer of the

> > Z-architectures will himself weigh in and elucidate me.  Meanwhile, I

> > shall pop the hood and inspect the repairs myself in the light of day,

> > with VOM in hand.  Bob...?

>

>It would be interesting to know where the field current comes from,

>and where the various automotive systems are getting their power

>(i.e. lights, fuel pumps, EFI, etc).

>

>If the "smart" voltage regulator actually shuts the alternator down

>during some periods, and the alternator had become electrically

>disconnected from the battery due to corrosion on the battery post,

>and the field current was getting its power from the alternator

>output, then it is plausible that there would be no way to start the

>alternator back up again.

>

>But, how were the other systems able to get the power they needed?

>Will the other systems run at lower voltages than is required to

>start the alternator back up again?

>

>Kevin Horton         RV-8 (finishing kit)

>Ottawa, Canada

>http://www.kilohotel.com/rv8

>





--



-- incoming mail is certified Virus Free.

Checked by AVG Anti-Virus.


	




        Bob . . .

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

      < What is so wonderful about scientific truth...is that >

      < the authority which determines whether there can be   >

      < debate or not does not reside in some fraternity of   >

      < scientists; nor is it divine. The authority rests     >

      < with experiment.                                      >

      <                            --Lawrence M. Krauss       >

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

sportav8r(at)gmail.com
Guest

Posted: Sun Oct 22, 2006 3:11 pm Post subject: automotive alternator question - OT

Wait - there's more!  You wanted data, so I went out and got you some.

 Hauled my son and my DVM out to the car repair place and jump-started

it for some measurements...



Battery reads 14.3 v after jump-starting.  Wait- it's dropping, all

the way to the low 12's.  Now it's back up to 14.3, but just for a

moment or two.  Now it's dropping all the way to 8 volts.  Now back to

14.3 again.  Every time the alternator comes alive I hear a slight

chirp from the serpentine belt just like when an A/C compressor kicks

in, but without the clack of the magnetic clutch.



Removal of battery terminal connection when the battery voltage is in

the 12 volt range kills the engine cold.



Prolonged observation of the battery voltage at idle and at various

revving rpm's and with and without headlight loads convinced me there

was no discernible pattern to the alternator coming back online- just

random.



Maybe Barry's contentions (excuse pun) are somewhat correct about a

fancy regulator in there somewhere, a quasi-intelligent (dumb-ass in

this case  circuit.



Not sure there will be a carcass to ship you, Bob.  Sorry I didn't

have a scope to look at waveforms and make a guess about diode health.

 Google is not showing me anything about this behavior in Hyundais,

but my search technique may need refinement.



I have at least some info to pass along to the repeir guys tomorrow

morning, but I can;'t help but think, Now what?!  I'd like to hard

wire the alternator to the battery and ignition switch like an

intelligent designer, but I fear the possible mayhem that might wreak

with the onboard computer and idiot light system.  Not liking my

alternatives much at this point.  Bad on Hyundai for a weak design, I

think.



-Bill B

 	  Quote: 	
		      Bill,



    If you can keep the core and send it to me, I'll reimburse

    your shipping and core value expenses. I'd like to put the

    carcass under the oscilloscope as it were . . .



    Bob . . .

nuckollsr(at)cox.net
Guest

Posted: Mon Oct 23, 2006 5:03 am Post subject: automotive alternator question - OT

At 07:08 PM 10/22/2006 -0400, you wrote:



 	  Quote: 	
		  



Wait - there's more!  You wanted data, so I went out and got you some.

Hauled my son and my DVM out to the car repair place and jump-started

it for some measurements...



Battery reads 14.3 v after jump-starting.  Wait- it's dropping, all

the way to the low 12's.  Now it's back up to 14.3, but just for a

moment or two.  Now it's dropping all the way to 8 volts.  Now back to

14.3 again.  Every time the alternator comes alive I hear a slight

chirp from the serpentine belt just like when an A/C compressor kicks

in, but without the clack of the magnetic clutch.



Removal of battery terminal connection when the battery voltage is in

the 12 volt range kills the engine cold.



Prolonged observation of the battery voltage at idle and at various

revving rpm's and with and without headlight loads convinced me there

was no discernible pattern to the alternator coming back online- just

random.


	


   Interesting!  It would be useful to measure voltages on small

   wires going into the back of the alternator to see if there

   is what appears to be a "command" signal that is turning the

   alternator ON/OFF . . . or whether the alternator itself is

   simply intermittent.



   Of course, the maintenance manuals SHOULD tell us about these

   things but that's a lot to hope for. I have a half dozen maintenance

   manuals on my shelves for the various cars I've owned. Electrically,

   these things are dismal teaching tools.

 	  Quote: 	
		  Not sure there will be a carcass to ship you, Bob.  Sorry I didn't

have a scope to look at waveforms and make a guess about diode health.

Google is not showing me anything about this behavior in Hyundais,

but my search technique may need refinement.



I have at least some info to pass along to the repeir guys tomorrow

morning, but I can;'t help but think, Now what?!  I'd like to hard

wire the alternator to the battery and ignition switch like an

intelligent designer, but I fear the possible mayhem that might wreak

with the onboard computer and idiot light system.  Not liking my

alternatives much at this point.  Bad on Hyundai for a weak design, I

think.


	


    Could be. Could be a flaky alternator. It will be interesting

    to see how much the mechanic knows about it . . . or perhaps

    he'll just replace parts until the problem goes away. Good

    luck!



    Bob . . .

sportav8r(at)gmail.com
Guest

Posted: Mon Oct 23, 2006 5:57 am Post subject: automotive alternator question - OT

Access to the small wires would be difficult, given the tightly packed

engine compartment and the fact that they're all housed in connectors

and wrapped tightly in harness sheathing, nevertheless, I think you're

right about the replace-parts-until-it's-fixed approach.  I sense

we're headed down that road.  Will await your reply to me later post

about the core carcass, etc.



Tnx, Bob.



-Bill B.

 	  Quote: 	
		      Interesting!  It would be useful to measure voltages on small

    wires going into the back of the alternator to see if there

    is what appears to be a "command" signal that is turning the

    alternator ON/OFF . . . or whether the alternator itself is

    simply intermittent.



    Of course, the maintenance manuals SHOULD tell us about these

    things but that's a lot to hope for. I have a half dozen maintenance

    manuals on my shelves for the various cars I've owned. Electrically,

    these things are dismal teaching tools.





     Could be. Could be a flaky alternator. It will be interesting

     to see how much the mechanic knows about it . . . or perhaps

     he'll just replace parts until the problem goes away. Good

     luck!



     Bob . . .

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