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dan(at)azshowersolutions.
Guest

Posted: Tue Apr 10, 2012 5:40 pm Post subject: Looking for suggestions

Well, the good news is I flew my Kitfox IV for the first time last Saturday. This was after 4 hours of ground work, taxi testing, etc. I have a brand new Rotax 912 ULS and it has been performing very well. I am running on the Aeroelectric Z-16 schematic and after I discovered my bridge rectifier was in backwards (between the main and essential buss), then replacing it the correct way, all has (I believed) behaved ok. Saturday I put 1 hour of air time on the plane doing a racetrack pattern, conversing with the class D tower many times without a hitch. Today I went up b-4 work talking to ground, the tower and then took the active. I commenced another racetrack pattern and when I went to contact tower to come down my radio went south (my 5 Amp fuse blew which is on the essential buss).  What a way to find out if your transponder is working or not as I squawked 7600 and came in via light gun. 

 I have been running the system with both the main buss as well as the essential buss turned on...why?...because I have an alternator whine in the headset when only the main switch is on. I found if I turned on the essential buss, the whine goes away. So to the questions: 

1.Should I not use the essential circuit unless it is, uh,well, essential to do so?

2. I have previously done a static (no engine running) Amp test across the essential switch with all loads going and even keyed the mic. The most I got out of the buss was 7A. I ask because Bob has a note not to go over 4A but I relayed this info here and some said  it should not be an issue.

3. My thoughts today have drifted to the bridge rectifier and I wonder if I might be better off using a good Schottky Diode (ie...AEC9001-1) as I have noticed my voltage go up when I turn on the E-buss (I know this is common from some previous posts) just covering all bases. 

4. So, I would welcome any thoughts of what to look at or ideas.

Thanks in advance,

Dan



   

 [quote][b]

nuckolls.bob(at)aeroelect
Guest

Posted: Tue Apr 10, 2012 7:53 pm Post subject: Looking for suggestions

At 08:37 PM 4/10/2012, you wrote:

Well, the good news is I flew my Kitfox IV for the first time last Saturday.



   Great! Send me pictures.



<snip>



Saturday I put 1 hour of air time on the plane doing a racetrack 

pattern, conversing with the class D tower many times without a 

hitch. Today I went up b-4 work talking to ground, the tower and then 

took the active. I commenced another racetrack pattern and when I 

went to contact tower to come down my radio went south (my 5 Amp fuse 

blew which is on the essential buss).



    What kind of radio?



What a way to find out if your transponder is working or not as I 

squawked 7600 and came in via light gun.



    It's always nice to have a plan-B,

    or plan-C, or . . .



I have been running the system with both the main buss as well as the 

essential buss turned on...why?...because I have an alternator whine 

in the headset when only the main switch is on. I found if I turned 

on the essential buss, the whine goes away. So to the questions:



1.Should I not use the essential circuit unless it is, uh,well, 

essential to do so?



    Actually, it's an ENDURANCE bus intended

    to supply power to devices most useful for

    en route operations to MAXIMIZE utilization

    of a limited resource . . . battery energy.



    Of course this feature is operative only with

    the battery contactor OFF and the alternate feed

    switch closed. There is no harm in conducing

    normal operations with both switches closed

    but the noise symptoms you cited are puzzling.



2. I have previously done a static (no engine running) Amp test 

across the essential switch with all loads going and even keyed the 

mic. The most I got out of the buss was 7A.



    Very good . . . it won't go up much, if any,

    with the engine running.



I ask because Bob has a note not to go over 4A but I relayed this 

info here and some said it should not be an issue.



   I'm pretty sure that the 4A reference was not

   a limit. I think I've writted than an e-bus

   load of 4A would probably be supported by an

   18 a.h. battery for duration of fuel aboard.

   But if your design goals call for less endurance

   and you need more current, so be it. The point

   is that you should PLAN for and then MAINTAIN

   a known level of e-bus performance with the

   alternator inoperative.



3. My thoughts today have drifted to the bridge rectifier and I 

wonder if I might be better off using a good Schottky Diode 

(ie...AEC9001-1) as I have noticed my voltage go up when I turn on 

the E-buss (I know this is common from some previous posts) just 

covering all bases.



   There is an EXPECTED and NORMAL shift in

   e-bus voltage when the alternate feed switch

   is closed. This doesn't present a performance

   problem. The shift can be minimized by use

   of a low voltage drop device like the Schottky

   diode but you won't be able to tell the difference

   from the pilot's seat.



4. So, I would welcome any thoughts of what to look at or ideas.



   We need to figure out where this noise is

   coming from and how it's getting into your

   electronics. You're sure it's coming from

   the alternator? In other words, if you went

   flying battery only, alternator off, would

   the radio be quiet.



   Also, have you figured out why the fuse

   opened?

   Bob . . .

dan(at)azshowersolutions.
Guest

Posted: Wed Apr 11, 2012 3:35 am Post subject: Looking for suggestions

 	  Quote: 	
		          



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



At 08:37 PM 4/10/2012, you wrote:

Well, the good news is I flew my Kitfox IV for the first time last Saturday.



  Great! Send me pictures.

Pictures attached...also this You Tube flic   http://www.youtube.com/watch?feature=player_embedded&v=acVvjlwjy5g 

<snip>



Saturday I put 1 hour of air time on the plane doing a racetrack pattern, conversing with the class D tower many times without a hitch. Today I went up b-4 work talking to ground, the tower and then took the active. I commenced another racetrack pattern and when I went to contact tower to come down my radio went south (my 5 Amp fuse blew which is on the essential buss).



   What kind of radio? Garmin SL-40



What a way to find out if your transponder is working or not as I squawked 7600 and came  in via light gun.



   It's always nice to have a plan-B,

   or plan-C, or . . . Yep, the plan B radio (HT) was conveniently left sitting in the hanger..first thing I threw into the plane when I got back. 



I have been running the system with both the main buss as well as the essential buss turned on...why?...because I have an alternator whine in the headset when only the main switch is on. I found if I turned on the essential buss, the whine goes away. So to the questions:



1.Should I not use the essential circuit unless it is, uh,well, essential to do so?



   Actually, it's an ENDURANCE bus intended

   to supply power to devices most useful for

   en route operations to MAXIMIZE utilization

   of a limited resource . . . battery energy.



   Of course this feature is operative only with

   the battery contactor OFF and the alternate feed

   switch closed. There is no harm in conducing

   normal operations with both switches closed

   but the noise symptoms you cited are puzzling.   ...To me as well



2. I have previously done a static (no engine running) Amp test across the essential switch with all loads going and even keyed the mic. The most I got out of the buss was 7A.



   Very good . . . it won't go up much, if any,

   with the engine running.



I ask because Bob has a note not to go over 4A but I relayed this info here and some said it should not be an issue.



  I'm pretty sure that the 4A reference was not

  a limit. I think I've writted than an e-bus

  load of 4A would probably be supported by an

  18 a.h. battery  for duration of fuel aboard.

  But if your design goals call for less endurance

  and you need more current, so be it. The point

  is that you should PLAN for and then MAINTAIN

  a known level of e-bus performance with the

  alternator inoperative. Understood...will chew on that a little more and try to justify switching another load to the main bus.



3. My thoughts today have drifted to the bridge rectifier and I wonder if I might be better off using a good Schottky Diode (ie...AEC9001-1) as I have noticed my voltage go up when I turn on the E-buss (I know this is common from some previous posts) just covering all  bases.



  There is an EXPECTED and NORMAL shift in

  e-bus voltage when the alternate feed switch

  is closed. This doesn't present a performance

  problem. The shift can be minimized by use

  of a low voltage drop device like the Schottky

  diode but you won't be able to tell the difference

  from the pilot's seat.



4. So, I would welcome any thoughts of what to look at or ideas.



  We need to figure out where this noise is

  coming from and how it's getting into your

  electronics. You're sure it's coming from

  the alternator? The only reason I connect it with the alternator is due to the whine following the RPMs of the engine. It is usually only noticeable during idle or slow taxi. As the RPM's hit about 3000...the whine frequency increases to such a high pitch it is not really detected ( or noticeable to the ear) 

In other words, if you went

  flying battery only, alternator off, would

  the radio be quiet. This sounds like something to try (think I will stay on the ground first  though)



  Also, have you figured out why the fuse

  opened? I have not. I didn't have time to check all of the fuses but didn't notice anything else inop. Will take a closer look today. As my radio (5A) fuse is the largest one on the E-Bus, I was thinking it odd it was the only one that went. 

Thanks for the ideas...Will report more later today.

Dan

  Bob . . . 



===========

http://www.matronics.com/Navigator?Aero====================

_-=             - List Contribution Web Site                            -Matt Dralle, List Admin.

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dan(at)azshowersolutions.
Guest

Posted: Wed Apr 11, 2012 6:36 pm Post subject: Looking for suggestions

Got to the plane after work and first checked the other fuses on the E-Bus...they were all ok. They include the SL-40, transponder, Garmin 396, HZ stab elect. trim, intercom and nav lights. As previously mentioned, the 5 A fuse for the radio was the only one that went when I keyed the mic. 

I replaced the fuse, pulled the plane out and taxied around getting radio checks from ground here and there and it worked fine. 

So...for the whine in the radio, yes,  it is an alternator whine. While the engine was running I turned off the ALT and the noise went away. (I still find it strange that the whine goes away when I turn on the E-Switch). Again, the noise becomes too high of a frequency to hear once the plane hits 3300 RPM. I took the plane back to the hanger and  started following  my "fat" wire that goes to the main bus. I found that it did parallel several small wires and came very close to the radio. Thought for sure I had it, so I re-routed the fat wire away from most other wires. Started it up...no joy. Still had the whine. I didn't have time today but I was thinking about isolating the com antenna to see if I might be getting a ground loop. I have EVERYTHING in the plane going to a ground bus with the exception of the com antenna (located in the vertical stab). There I tied into the chrome alloy frame instead of running a ground wire all the way back to the front. Well, that's my story and I'm sticking to it...any guestimates?

Thanks,

Dan



[quote]        From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>

 To: aeroelectric-list(at)matronics.com 

 Sent: Tuesday, April 10, 2012 8:50 PM

 Subject: Re: Looking for suggestions

  

 

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



At 08:37 PM 4/10/2012, you wrote:

Well, the good news is I flew my Kitfox IV for the first time last Saturday.



  Great! Send me pictures.



<snip>



Saturday I put 1 hour of air time on the plane doing a racetrack pattern, conversing with the class D tower many times without a hitch. Today I went up b-4 work talking to ground, the tower and then took the active. I commenced another racetrack pattern and when I went to contact tower to come down my radio went south (my 5 Amp fuse blew which is on the essential buss).



   What kind of radio?



What a way to find out if your transponder is working or not as I squawked 7600 and came in via light gun.



   It's always nice to have a  plan-B,

   or plan-C, or . . .



I have been running the system with both the main buss as well as the essential buss turned on...why?...because I have an alternator whine in the headset when only the main switch is on. I found if I turned on the essential buss, the whine goes away. So to the questions:



1.Should I not use the essential circuit unless it is, uh,well, essential to do so?



   Actually, it's an ENDURANCE bus intended

   to supply power to devices most useful for

   en route operations to MAXIMIZE utilization

   of a limited resource . . . battery energy.



   Of course this feature is operative only with

   the battery contactor OFF and the alternate feed

   switch closed. There is no harm in conducing

   normal operations with both switches closed

   but the noise symptoms you cited are puzzling.



2. I have previously done a static (no  engine running) Amp test across the essential switch with all loads going and even keyed the mic. The most I got out of the buss was 7A.



   Very good . . . it won't go up much, if any,

   with the engine running.



I ask because Bob has a note not to go over 4A but I relayed this info here and some said it should not be an issue.



  I'm pretty sure that the 4A reference was not

  a limit. I think I've writted than an e-bus

  load of 4A would probably be supported by an

  18 a.h. battery for duration of fuel aboard.

  But if your design goals call for less endurance

  and you need more current, so be it. The point

  is that you should PLAN for and then MAINTAIN

  a known level of e-bus performance with the

  alternator inoperative.



3. My thoughts today have drifted to the bridge rectifier and I wonder if I might be better off using a good Schottky  Diode (ie...AEC9001-1) as I have noticed my voltage go up when I turn on the E-buss (I know this is common from some previous posts) just covering all bases.



  There is an EXPECTED and NORMAL shift in

  e-bus voltage when the alternate feed switch

  is closed. This doesn't present a performance

  problem. The shift can be minimized by use

  of a low voltage drop device like the Schottky

  diode but you won't be able to tell the difference

  from the pilot's seat.



4. So, I would welcome any thoughts of what to look at or ideas.



  We need to figure out where this noise is

  coming from and how it's getting into your

  electronics. You're sure it's coming from

  the alternator? In other words, if you went

  flying battery only, alternator off, would

  the radio be quiet.



  Also, have you figured out why the fuse

  ics.com/Navigator?AeroElectric-List" target="_blank">http://www.matronics;    - p;             -Matt Dralle, List Admin.

_-=   -->

rickofudall

Joined: 19 Sep 2009
Posts: 1392
Location: Udall, KS, USA

Posted: Thu Apr 12, 2012 5:08 pm Post subject: Looking for suggestions

Dan, Did you put the electrolytic capacitor on the DC line coming from the voltage regulator per Rotax Installation manual page 111 and Z-16? that should take care of alternator whine. If you did put it in, make sure it's the correct value and it's hooked up correctly. Be careful if you disconnect it, they hold a charge for a long time (months!). 



Rick Girard



On Wed, Apr 11, 2012 at 9:32 PM, Dan Billingsley <dan(at)azshowersolutions.com (dan(at)azshowersolutions.com)> wrote:

  	  Quote: 	
		  Got to the plane after work and first checked the other fuses on the E-Bus...they were all ok. They include the SL-40, transponder, Garmin 396, HZ stab elect. trim, intercom and nav lights. As previously mentioned, the 5 A fuse for the radio was the only one that went when I keyed the mic. 

 I replaced the fuse, pulled the plane out and taxied around getting radio checks from ground here and there and it worked fine. 

So...for the whine in the radio, yes,  it is an alternator whine. While the engine was running I turned off the ALT and the noise went away. (I still find it strange that the whine goes away when I turn on the E-Switch). Again, the noise becomes too high of a frequency to hear once the plane hits 3300 RPM. I took the plane back to the hanger and  started following  my "fat" wire that goes to the main bus. I found that it did parallel several small wires and came very close to the radio. Thought for sure I had it, so I re-routed the fat wire away from most other wires. Started it up...no joy. Still had the whine. I didn't have time today but I was thinking about isolating the com antenna to see if I might be getting a ground loop. I have EVERYTHING in the plane going to a ground bus with the exception of the com antenna (located in the vertical stab). There I tied into the chrome alloy frame instead of running a ground wire all the way back to the front. Well, that's my story and I'm sticking to it...any guestimates?

 Thanks,

Dan



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

  To: aeroelectric-list(at)matronics.com (aeroelectric-list(at)matronics.com) 

 Sent: Tuesday, April 10, 2012 8:50 PM

  Subject: Re: AeroElectric-List: Looking for suggestions

  

 

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



At 08:37 PM 4/10/2012, you wrote:

 Well, the good news is I flew my Kitfox IV for the first time last Saturday.



  Great! Send me pictures.



<snip>



Saturday I put 1 hour of air time on the plane doing a racetrack pattern, conversing with the class D tower many times without a hitch. Today I went up b-4 work talking to ground, the tower and then took the active. I commenced another racetrack pattern and when I went to contact tower to come down my radio went south (my 5 Amp fuse blew which is on the essential buss).

 

   What kind of radio?



What a way to find out if your transponder is working or not as I squawked 7600 and came in via light gun.



   It's always nice to have a  plan-B,

   or plan-C, or . . .



I have been running the system with both the main buss as well as the essential buss turned on...why?...because I have an alternator whine in the headset when only the main switch is on. I found if I turned on the essential buss, the whine goes away. So to the questions:

 

1.Should I not use the essential circuit unless it is, uh,well, essential to do so?



   Actually, it's an ENDURANCE bus intended

   to supply power to devices most useful for

   en route operations to MAXIMIZE utilization

    of a limited resource . . . battery energy.



   Of course this feature is operative only with

   the battery contactor OFF and the alternate feed

   switch closed. There is no harm in conducing

   normal operations with both switches closed

    but the noise symptoms you cited are puzzling.



2. I have previously done a static (no  engine running) Amp test across the essential switch with all loads going and even keyed the mic. The most I got out of the buss was 7A.



   Very good . . . it won't go up much, if any,

   with the engine running.

 

I ask because Bob has a note not to go over 4A but I relayed this info here and some said it should not be an issue.



  I'm pretty sure that the 4A reference was not

  a limit. I think I've writted than an e-bus

   load of 4A would probably be supported by an

  18 a.h. battery for duration of fuel aboard.

  But if your design goals call for less endurance

  and you need more current, so be it. The point

  is that you should PLAN for and then MAINTAIN

   a known level of e-bus performance with the

  alternator inoperative.



3. My thoughts today have drifted to the bridge rectifier and I wonder if I might be better off using a good Schottky  Diode (ie...AEC9001-1) as I have noticed my voltage go up when I turn on the E-buss (I know this is common from some previous posts) just covering all bases.



  There is an EXPECTED and NORMAL shift in

  e-bus voltage when the alternate feed switch

   is closed. This doesn't present a performance

  problem. The shift can be minimized by use

  of a low voltage drop device like the Schottky

  diode but you won't be able to tell the difference

  from the pilot's seat.

 

4. So, I would welcome any thoughts of what to look at or ideas.



  We need to figure out where this noise is

  coming from and how it's getting into your

  electronics. You're sure it's coming from

   the alternator? In other words, if you went

  flying battery only, alternator off, would

  the radio be quiet.



  Also, have you figured out why the fuse

  ics.com/Navigator?AeroElectric-List" target="_blank">http://www.matronics;    -  href="http://www.matronics.com/contribution" target="_blank">





 

 

 



ist" target="_blank">http://www.matronics.com/Navigator?AeroElectric-List

tp://forums.matronics.com

_blank">http://www.matronics.com/contribution



	


	




-- 

Zulu Delta

Mk IIIC

Thanks, Homer GBYM

It isn't necessary to have relatives in Kansas City in order to be unhappy.

   - Groucho Marx



 

  [quote][b]

_________________
The smallest miracle right in front of you is enough to make you happy....

dan(at)azshowersolutions.
Guest

Posted: Thu Apr 12, 2012 9:07 pm Post subject: Looking for suggestions

Bob, did you have any other thoughts on this? Could the antenna grounding be connected to hearing the Alt and or single out the 5A fuse to the radio. I have been reading the Connection again and I feel my next step might be to add a cap & or an inductor.

Got to the plane after work and first checked the other fuses on the E-Bus...they were all ok. They include the SL-40, transponder, Garmin 396, HZ stab elect. trim, intercom and nav lights. As previously mentioned, the 5 A fuse for the radio was the only one that went when I keyed the mic. 

I replaced the fuse, pulled the plane out and taxied around getting radio checks from ground here and there and it worked fine. 

So...for  the whine in the radio, yes,  it is an alternator whine. While the engine was running I turned off the ALT and the noise went away. (I still find it strange that the whine goes away when I turn on the E-Switch). Again, the noise becomes too high of a frequency to hear once the plane hits 3300 RPM. I took the plane back to the hanger and started following  my "fat" wire that goes to the main bus. I found that it did parallel several small wires and came very close to the radio. Thought for sure I had it, so I re-routed the fat wire away from most other wires. Started it up...no joy. Still had the whine. I didn't have time today but I was thinking about isolating the com antenna to see if I might be getting a ground loop. I have EVERYTHING in the plane going to a ground bus with the exception of the com antenna (located in the vertical stab). There I tied into the chrome alloy frame instead of running a ground wire all the way back to the front.  Well, that's my story and I'm sticking to it...any guestimates?

Thanks,

Dan

[quote]        From: "Robert L. Nuckolls, III" <nuckolls.bob(at)aeroelectric.com>

 To: aeroelectric-list(at)matronics.com 

 Sent: Tuesday, April 10, 2012 8:50 PM

 Subject: Re: Looking for suggestions

  

 

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



At 08:37 PM 4/10/2012, you wrote:

Well, the good news is I flew my Kitfox IV for the first time last Saturday.



  Great! Send me pictures.



<snip>



Saturday I put 1 hour of air time on the plane doing a racetrack pattern, conversing with the class D tower many times without a hitch. Today I went up b-4 work talking to ground, the tower and then took the active. I commenced another racetrack pattern and when I went to contact tower to come down my radio went south (my 5 Amp fuse blew which is on the essential buss).



   What kind of radio?



What a way to find out if your transponder is working or not as I squawked 7600 and came in via light gun.



   It's always nice to have a  plan-B,

   or plan-C, or . . .



I have been running the system with both the main buss as well as the essential buss turned on...why?...because I have an alternator whine in the headset when only the main switch is on. I found if I turned on the essential buss, the whine goes away. So to the questions:



1.Should I not use the essential circuit unless it is, uh,well, essential to do so?



   Actually, it's an ENDURANCE bus intended

   to supply power to devices most useful for

   en route operations to MAXIMIZE utilization

   of a limited resource . . . battery energy.



   Of course this feature is operative only with

   the battery contactor OFF and the alternate feed

   switch closed. There is no harm in conducing

   normal operations with both switches closed

   but the noise symptoms you cited are puzzling.



2. I have previously done a static (no  engine running) Amp test across the essential switch with all loads going and even keyed the mic. The most I got out of the buss was 7A.



   Very good . . . it won't go up much, if any,

   with the engine running.



I ask because Bob has a note not to go over 4A but I relayed this info here and some said it should not be an issue.



  I'm pretty sure that the 4A reference was not

  a limit. I think I've writted than an e-bus

  load of 4A would probably be supported by an

  18 a.h. battery for duration of fuel aboard.

  But if your design goals call for less endurance

  and you need more current, so be it. The point

  is that you should PLAN for and then MAINTAIN

  a known level of e-bus performance with the

  alternator inoperative.



3. My thoughts today have drifted to the bridge rectifier and I wonder if I might be better off using a good Schottky  Diode (ie...AEC9001-1) as I have noticed my voltage go up when I turn on the E-buss (I know this is common from some previous posts) just covering all bases.



  There is an EXPECTED and NORMAL shift in

  e-bus voltage when the alternate feed switch

  is closed. This doesn't present a performance

  problem. The shift can be minimized by use

  of a low voltage drop device like the Schottky

  diode but you won't be able to tell the difference

  from the pilot's seat.



4. So, I would welcome any thoughts of what to look at or ideas.



  We need to figure out where this noise is

  coming from and how it's getting into your

  electronics. You're sure it's coming from

  the alternator? In other words, if you went

  flying battery only, alternator off, would

  the radio be quiet.



  Also, have you figured out why the fuse

  ics.com/Navigator?AeroElectric-List" target="_blank">http://www.matronics;    - p;             -Matt Dralle, List Admin.

_-=   -->

user9253

Joined: 28 Mar 2008
Posts: 1921
Location: Riley TWP Michigan

Posted: Fri Apr 13, 2012 6:11 am Post subject: Re: Looking for suggestions

 	  Quote: 	
		  (I still find it strange that the whine goes away when I turn on the E-Switch 	


Since the whine is still there after re-routing the fat wires, it seems as if the whine is filtered out when the current passes through the battery on its way from the alternator to the radio via the E-Bus switch.  The easiest solution to the whine problem is to do nothing except to leave the E-Bus switch on.  Doing so will not hurt anything unless the pilot forgets to shut it off at the end of a flight or forgets to shut it off in the event of smoke in the cockpit.

  Another possible solution is to install a filter in series with the radio or in series with the E-Bus diode.  Or a large capacitor connected from the Radio 12V supply to ground might help.

 As for the radio fuse blowing, what type of fuse is it?  The old automotive glass type of fuses are prone to fail.  Even if the fuse is the ATC / ATO type, I would not be too concerned unless the fuse blows a second time.

Joe

_________________
Joe Gores

john.maccallum(at)bigpond
Guest

Posted: Fri Apr 13, 2012 2:01 pm Post subject: Looking for suggestions

The Whine is a function of ripple in the output Voltage of the Alternator

and it is dependent on current flow.

Depending on how you have wired things up when you turn the E bus on you are

most likely reducing the current being

drawn from the main Alternator.  Less Current, less voltage sag from the

Peak Voltage on the Main Buss and therefore less

whine. I would re-visit all of the connections in the Main Buss to main

alternator.



The Voltage regulation needs to be checked as well. Is it Internal or

external? Check the condition of the Alternator

Slip rings and brushes if these are ok sometimes replacing the diode pack

gets rid of a noisy diode.



If no joy with the above try getting rid of it by installing an output

capacitor and is this doesn't solve the problem

investigate a high current Loss Pass filter arrangement with an Choke in

series and the filter capacitor in Parallel.



You can buy these high current chokes these days quite easily from a Car

Audio specialist supply house.



Cheers



John MacCallum

VH-DUU

41016

--

dan(at)azshowersolutions.
Guest

Posted: Fri Apr 13, 2012 2:38 pm Post subject: Looking for suggestions

Thanks Joe and John, that gives me some more to think about and tinker with. Unfortunately the alternator is tucked into the back of a Rotax 912S and the only way to get to it would be to pull the engine. Will try several of the other things first and then may just live with it for as long as I can.

Appreciate the thoughts and suggestions,

Dan



From: user9253 <fran4sew(at)banyanol.com>

To: aeroelectric-list(at)matronics.com

Sent: Fri, April 13, 2012 7:11:55 AM

Subject: Re: Looking for suggestions



 --> AeroElectric-List message posted by: "user9253" <fran4sew(at)banyanol.com (fran4sew(at)banyanol.com)>

 	  Quote: 	
		   (I still find it strange that the whine goes away when I turn on the E-Switch


	


Since the whine is still there after re-routing the fat wires, it seems as if the whine is filtered out when the current passes through the battery on its way from the alternator to the radio via the E-Bus switch.  The easiest solution to the whine problem is to do nothing except to leave the E-Bus switch on.  Doing so will not hurt anything unless the pilot forgets to shut it off at the end of a flight or forgets to shut it off in the event of smoke in the cockpit.

  Another possible solution is to install a filter in series with the radio or in series with the E-Bus diode.  Or a large capacitor connected from the Radio 12V supply to ground might help.

 As for the   

 [quote][b]

user9253

Joined: 28 Mar 2008
Posts: 1921
Location: Riley TWP Michigan

Posted: Fri Apr 13, 2012 3:26 pm Post subject: Re: Looking for suggestions

I was not thinking very clearly when I posted above that the alternator current passes through the battery on its way to the radio via the E-bus switch.  The moving electrons get closer to the battery but do not pass through it.

  The filter suggested by John MacCallum is worth a try.

 I am curious to know if the diode has anything to do with the alternator whine.  With the E-bus switch remaining off, short across the diode with a jumper to see if the whine goes away.

  The alternator on the Rotax 912 is actually a single phase dynamo with permanent magnets.  Other than a wire breaking, there is not very much that can go wrong with it.  The permanent magnets are integral with the flywheel.  As long as the engine is running, so are the magnets spinning with the flywheel.  The external voltage regulator also rectifies the AC output of the dynamo.

  It is not as easy to smooth out the AC ripple of the Rotax single phase dynamo compared to a 3 phase alternator.

Joe

_________________
Joe Gores

maca2790

Joined: 26 Jan 2011
Posts: 59
Location: Australia

Posted: Fri Apr 13, 2012 7:24 pm Post subject: Re: Looking for suggestions

I'm not familiar with the Rotax Alternator/ Dynamo

A Dynamo is a DC device that is self exciting but an Alternator can be

either self exciting or externally excited.



Don't short out the Diode because if it's a Alternator you will induce

a dead short to ground.



I just looked at the Circuit diagram. From the diagram it appears to be an

Alternator. If Joe is correct with it being only single phase output then

that is the source of the whine. The Ripple frequency will be twice the 

Alternators RPM. Probably exactly in the right range for it to be

annoying in the Headset.



Switching the external Alternator on reduces the current flow from the

Internal and transfers it to the other. ( the one with the highest output

Voltage wins)



If you want to stick with the Internal Alternator you really don't have 

much choice but to try a Low Pass Filter as I suggested. 

I would leave the External Alternator on and run off it if it has the Capacity to do that.



cheers



John MacCallum

user9253

Joined: 28 Mar 2008
Posts: 1921
Location: Riley TWP Michigan

Posted: Sat Apr 14, 2012 2:05 am Post subject: Re: Looking for suggestions

 	  Quote: 	
		  Don't short out the Diode because if it's a Alternator you will induce a dead short to ground. 	


John MacCallum,

Maybe we are talking about different diodes.  I was referring to the E-Bus diode.  Shorting across it (not to ground) will not hurt anything because current is limited by the E-Bus loads.

  If I read Dan's posts correctly, his plane (wired per Z-16) only has one dynamo, no alternator.  Although an alternator is available as an option for the Rotax 912.  But it would add expense, weight, and a bulge in the cowling.

  John, I like your suggestion of trying a filter.

Joe

_________________
Joe Gores

dan(at)azshowersolutions.
Guest

Posted: Sat Apr 14, 2012 5:28 am Post subject: Looking for suggestions

John and Joe, 

Again thank you for your assistance...Joe is correct in I am only operating off of the internal Rotax Alt/ Dynamo. Understanding that the dynamo is only a single phase makes sense that the peak interference would be a bit higher. As previously indicated, I have been questioning the diode between the main and e-bus as well. The thought to jumper (bypass) the diode is a good idea before I go buy either one of the schottkey diodes from Bob or try another Radio Shack bridge rectifier (which is currently in place). Sticking a filter / choke is certainly an inexpensive effort also. I might even test my 22,000uf cap to see if it is bad or not as it should be giving some help coming off of the external regulator. Always a good time running down the  gremlins.

Dan

 	  Quote: 	
		          From: user9253 <fran4sew(at)banyanol.com>

 To: aeroelectric-list(at)matronics.com 

 Sent: Saturday, April 14, 2012 3:05 AM

 Subject: Re: Looking for suggestions

 --> AeroElectric-List message posted by: "user9253" <fran4sew(at)banyanol.com (fran4sew(at)banyanol.com)>

 	  Quote: 	
		   Don't short out the Diode because if it's a Alternator you will induce a dead short to ground.

John MacCallum,

Maybe we are talking about different diodes.  I was referring to the E-Bus diode.  Shorting across it (not to ground) will not hurt anything because current is limited by the E-Bus loads.

  If I read Dan's posts correctly, his plane (wired per Z-16) only has one dynamo, no alternator.  Although an alternator is available as an option for the Rotax 912.  But it would add expense, weight, and a bulge in the cowling.

  John, I like your suggestion of trying a filter.

Joe

--------

Joe Gores

Read this topic online  here:

http://forums.matronics.com/viewtopic.php?p=370767#370767http://www.matronics.com/Navigator?               - MATRONICS WEB FORUMS -<                    &nbsp========================

 [quote][b]

user9253

Joined: 28 Mar 2008
Posts: 1921
Location: Riley TWP Michigan

Posted: Sat Apr 14, 2012 10:50 am Post subject: Testing the Rotax 22,000ÂµF Capacitor

Here is a simple and foolproof method of testing the Rotax 22,000ÂµF capacitor.  

Buy a miniature 12V lamp, Radio Shack 272-1141, or equivalent.  

Remove the capacitor from the circuit and charge it with 12vdc (observe polarity).

Disconnect the charging power source.

Connect the miniature lamp to the capacitor.

The lamp should glow brightly at first, then slowly dim as the capacitor is discharged.

The total time from when the lamp first illuminates until it stops glowing red should be about 15 seconds.  At least my lamp did.  Your parts may vary.

Joe

_________________
Joe Gores

klehman(at)albedo.net
Guest

Posted: Sun Apr 15, 2012 5:33 am Post subject: Looking for suggestions

That is indeed probably an excellent and simple test for this situation.



Not sure it is completely foolproof though. (is anything?) I've replaced 

capacitors in other applications that were within limits for capacitance 

(which this test checks) but they had too high Equivalent Series 

Resistance (ESR) to effectively filter a power supply.



Apologies for splitting hairs but claims of anything being "completely 

foolproof" always sounds like a challenge to me 



As far as the original thread goes I would add that I've never bothered 

to install the often recommended capacitor on my single phase 20 amp 

John Deere permanent magnet alternator/dynamo and have never had any 

alternator noise. However it is in a z-14 configuration which means it 

is always connected to a small 8AH battery.



Ken



On 14/04/2012 2:50 PM, user9253 wrote:

 	  Quote: 	
		   

 "user9253"<fran4sew(at)banyanol.com>



 Here is a simple and foolproof method of testing the Rotax 22,000ÂµF

 capacitor. Buy a miniature 12V lamp, Radio Shack 272-1141, or

 equivalent. Remove the capacitor from the circuit and charge it with

 12vdc (observe polarity). Disconnect the charging power source.

 Connect the miniature lamp to the capacitor. The lamp should glow

 brightly at first, then slowly dim as the capacitor is discharged.

 The total time from when the lamp first illuminates until it stops

 glowing red should be about 15 seconds.  At least my lamp did.  Your

 parts may vary. Joe



 -------- Joe Gores

nuckolls.bob(at)aeroelect
Guest

Posted: Sun Apr 15, 2012 6:41 am Post subject: Looking for suggestions

At 08:33 AM 4/15/2012, you wrote:

 	  Quote: 	
		  



That is indeed probably an excellent and simple test for this situation.



Not sure it is completely foolproof though. (is 

anything?) I've replaced capacitors in other 

applications that were within limits for 

capacitance (which this test checks) but they 

had too high Equivalent Series Resistance (ESR) 

to effectively filter a power supply.



As far as the original thread goes I would add 

that I've never bothered to install the often 

recommended capacitor on my single phase 20 amp 

John Deere permanent magnet alternator/dynamo 

and have never had any alternator noise. However 

it is in a z-14 configuration which means it is 

always connected to a small 8AH battery.


	


   This has the look and smell of a ground-loop issue.

   A few years back, I looked at the relative effectiveness

   of filtering the ripple component off a the B&C SD-8 alternator.

   One captured trace can be seen here:



http://tinyurl.com/73tusru



   Here you can see a ripple component on the order of

   2.5 volts pk-pk. When the capacitor was disconnected,

   there was little, if any, observable difference

   in the 'noise'.



   We also know that except for conditions where the battery

   is being heavily charged or discharged, the battery's

   effective impedance across the bus is very high. Thus,

   batteries are of little service in reducing noises that

   wiggle the bus around in the range of 12.5 to 14.5 volts



   Given the demonstrated success of PM alternator installations

   on so many airplanes it seems likely that the problem in

   this case has more to do with a variable in grounding than

   any failure of a component to perform as advertised.



   Bob . . .



 	  Quote: 	
		  Ken



On 14/04/2012 2:50 PM, user9253 wrote:

>

>"user9253"<fran4sew(at)banyanol.com>

>

>Here is a simple and foolproof method of testing the Rotax 22,000ÂµF

>capacitor. Buy a miniature 12V lamp, Radio Shack 272-1141, or

>equivalent. Remove the capacitor from the circuit and charge it with

>12vdc (observe polarity). Disconnect the charging power source.

>Connect the miniature lamp to the capacitor. The lamp should glow

>brightly at first, then slowly dim as the capacitor is discharged.

>The total time from when the lamp first illuminates until it stops

>glowing red should be about 15 seconds.  At least my lamp did.  Your

>parts may vary. Joe

>

>-------- Joe Gores

>



-----

No virus found in this message.

Checked by AVG - www.avg.com


	




   Bob . . .

dan(at)azshowersolutions.
Guest

Posted: Sun Apr 15, 2012 6:42 am Post subject: Looking for suggestions

Joe, that's a good thought using a lamp...If one has a simple Volt meter / multi meter, you could actually watch the numbers come down as the discharge occurs. Might want to throw a small resistor in there to generate a bit of a load. What I'm not certain of is what the potential  voltage would be expected on a full 22,000uF. Using a lower end MM would need to set the V  high enough I believe. 

Dan

 	  Quote: 	
		          From: user9253 <fran4sew(at)banyanol.com>

 To: aeroelectric-list(at)matronics.com 

 Sent: Saturday, April 14, 2012 11:50 AM

 Subject: Re: Looking for suggestions

 --> AeroElectric-List message posted by: "user9253" <fran4sew(at)banyanol.com (fran4sew(at)banyanol.com)>

Here is a simple and foolproof method of testing the Rotax 22,000ÂµF capacitor.  

Buy a miniature 12V lamp, Radio Shack 272-1141, or equivalent.  

Remove the capacitor from the circuit and charge it with 12vdc (observe polarity).

Disconnect the charging power source.

Connect the miniature lamp to the capacitor.

The lamp should glow brightly at first, then slowly dim as the capacitor is discharged.

The total time from when the lamp first illuminates until it stops glowing red should be about 15 seconds.  At least my lamp did.  Your parts may vary.

Joe

--------

Joe Gores

Read this topic online  here:

http://forums.matronics.com/viewtopic.php?p=370786#370786http://www.matronics.com/Navigator?               - MATRONICS WEB FORUMS -<                    &nbsp========================

 [quote][b]

user9253

Joined: 28 Mar 2008
Posts: 1921
Location: Riley TWP Michigan

Posted: Sun Apr 15, 2012 7:45 am Post subject: Re: Looking for suggestions

Dan,

A resistor is not necessary as the lamp provides a load.

The voltage of a capacitor can never be more than the voltage that was used  to charge it up.

  According to Ken and Bob's posts above, a capacitor is not very effective at alleviating noise.

  Are the headset jacks electrically isolated from the aircraft frame with insulating washers?

Joe

_________________
Joe Gores

dan(at)azshowersolutions.
Guest

Posted: Sun Apr 15, 2012 11:51 am Post subject: Looking for suggestions

[quote]        From: user9253 <fran4sew(at)banyanol.com>

 To: aeroelectric-list(at)matronics.com 

 Sent: Sunday, April 15, 2012 8:45 AM

 Subject:  Re: Looking for suggestions

 --> AeroElectric-List message posted by: "user9253" <fran4sew(at)banyanol.com (fran4sew(at)banyanol.com)>

Dan,

A resistor is not necessary as the lamp provides a load.

Yeah, I was just thinking of getting around not using the lamp and getting a digital reading of the discharging cap.

The voltage of a capacitor can never be more than the voltage that was used  to charge it up.

..I am always willing to be corrected and learned...but I must disagree that if a 22,000mF is filled up, then when  discharged there will be a much higher initial voltage reading than let's say the 12 V battery that charged it. Example: if you take one of the disposable cameras that use a flash and run a positive and negative lead off of that electrolytic cap...hook it up to a volt meter and press the button, I have gotten between 300 and 400 volts each time. Most of these cameras use a AA (or 1.5V cell).

  According to Ken and Bob's posts above, a capacitor is not very effective at alleviating noise. Agreed...so I might want to look at a choke?

  Are the headset jacks electrically isolated from the aircraft frame with insulating washers? Yes, the jacks were the first thing I checked when I was introduced to  my system whine. Could that frame-grounded antenna in the back be a factor?

Thanks for all the assistance. And someone set me straight if I am off base about the caps holding high voltages.

Dan 

Joe

--------

Joe Gores

Read this topic online here:

http://forums.matronics.com/viewtopic.php?p=370863#370863<;         - The AeroElectric-List Email Forum -

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

_-=               - MATRONICS WEB FORUMo available via the Web Forums!

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

 [b]

ceengland(at)bellsouth.ne
Guest

Posted: Sun Apr 15, 2012 12:53 pm Post subject: Looking for suggestions

On 04/15/2012 02:46 PM, Dan Billingsley wrote:      	  Quote: 	
		                  

           

         

            	  Quote: 	
		                                                                      From:                     user9253 <fran4sew(at)banyanol.com> (fran4sew(at)banyanol.com)

                     To:                     aeroelectric-list(at)matronics.com (aeroelectric-list(at)matronics.com) 

                     Sent:                     Sunday, April 15, 2012 8:45 AM

                     Subject:                     Re: Looking for suggestions

                    

                 

                 --> AeroElectric-List message posted by: "user9253"                 <fran4sew(at)banyanol.com (fran4sew(at)banyanol.com)>

                 

                 Dan,

                 A resistor is not necessary as the lamp provides a load.

               Yeah,                     I was just thinking of getting around not using the                     lamp and getting a digital reading of the                     discharging cap.

                 The voltage of a                   capacitor can never be more than the voltage that was                   used  to charge it up.

               ..I                   am always willing to be corrected and learned...but I                   must disagree that                   if a 22,000mF is filled up, then when discharged there                   will be a much higher initial voltage reading than                   let's say the 12 V battery that charged it. Example:                   if you take one of the disposable cameras that use a                   flash and run a positive and negative lead off of that                   electrolytic cap...hook it up to a volt meter and                   press the button, I have gotten between 300 and 400                   volts each time. Most of these cameras use a AA (or                   1.5V cell).

                   According to Ken and                   Bob's posts above, a capacitor is not very effective                   at alleviating noise. Agreed...so I might want to look at a                     choke?

                   Are the headset                     jacks electrically isolated from the aircraft frame                     with insulating washers? Yes,                       the jacks were the first thing I checked when I                       was introduced                       to my system whine. Could that frame-grounded                       antenna in the back be a factor?

               

                     

               Thanks                       for all the assistance. And someone set me                       straight if I am off base about the caps holding                       high voltages.

               Dan 

                 Joe

                 

                 --------

                 Joe Gores

               

             

           	
         

       

     	
     Sorry Joe, but what you're seeing with the disposable flash camera     capacitor is the result of the charging circuit. It takes high     voltage to fire a flash tube. The flash circuit takes the low DC     battery voltage and drives a 'switching' (oscillator) power supply     with it to make AC. There's a tiny transformer (or possibly a     'ladder diode/capacitor' type circuit) in the unit that takes the     low voltage AC & steps it up to several hundred volts, &     then there's a high voltage rectifier that converts it back to DC,     which charges the high voltage capacitor that you found. If you put     your meter leads on the cap itself, fire the flash, and watch the     meter as the flash recharges, you will probably be able to watch the     voltage rise to several hundred volts as the capacitor takes on its     charge for the next flash. If you're lucky enough to get one with     markings on it, look at the voltage rating. It will be higher than     whatever voltage you are measuring. A 12V capacitor (at any     capacitance) will turn into a mini-grenade if you hit it with     several hundred volts.

     

      	  Quote: 	
		                http://electronics.howstuffworks.com/camera-flash2.htm 	
     

     

     Hope that helps,

     

     Charlie

     

     

     

     

      [quote][b]

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