Today's Message Index:
----------------------
1. 03:38 AM - Generator vs. Alternator (Was: Voltage Regs) (Brian Lloyd)
2. 07:43 AM - Re: Battery Set Up (Ron Davis)
3. 08:38 AM - Re: Battery Set Up (Brian Lloyd)
4. 09:19 AM - Re: test (Walt Lannon)
5. 09:41 AM - Re: Battery Set Up (Ernie)
6. 10:12 AM - Re: Battery Set Up (Ernie)
7. 10:15 AM - Re: Battery Set Up (Brian Lloyd)
8. 10:36 AM - Question (Walt Murphy)
9. 10:55 AM - Re: Battery Set Up (Brian Lloyd)
10. 11:21 AM - Re: Question (Jim Selby)
11. 11:25 AM - Re: Question (Jim Selby)
12. 11:28 AM - Re: Question (Doug Sapp)
13. 11:44 AM - Re: Battery Set Up (Ernie)
14. 12:36 PM - Re: Battery Set Up (Brian Lloyd)
15. 01:04 PM - Re: Battery Set Up (Jim Griffin)
16. 01:14 PM - Re: Battery Set Up (cjpilot710@aol.com)
17. 01:46 PM - Re: Battery Set Up (Ernie)
18. 01:58 PM - Email address (Graeme Frew)
19. 01:58 PM - Re: Generator vs. Alternator (Was: Voltage Regs) (Graeme Frew)
20. 02:14 PM - Re: Battery Set Up (Brian Lloyd)
21. 07:22 PM - stuff 4 sale. (cjpilot710@aol.com)
22. 08:38 PM - Re: Skyfest 2004...Last Call (Bpx2horn@aol.com)
23. 11:39 PM - Re: Battery Set Up (Mike Brogley)
Message 1
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| Subject: | Generator vs. Alternator (Was: Voltage Regs) |
--> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
On Sep 22, 2004, at 1:31 AM, Graeme Frew wrote:
> --> Yak-List message posted by: "Graeme Frew" <gfrew@attglobal.net>
>
> OK,
> So instead of getting two carbon pile regs I now have two solid state
> regs. Would anyone know whether I can replace my old style reg with a
> solid state one without spending a fortune. I don't have this
> mysterious diode nor do I have any wiring diagram. To compound the
> problem I have a complete lack of knowledge and understanding of
> wiggly amps.
I am wondering why anyone bothers to troubleshoot and maintain the old
generator. Switching to an alternator buys you the following:
1. smaller;
2. lighter;
3. comes on-line at a lower RPM;
4. much simpler so fewer things to go wrong;
5. much simpler wiring;
6. cheaper;
7. parts readily available;
8. less potential for electrical interference with the avionics.
Given the cost of a heavy-duty 28V truck alternator, spending money to
acquire replacement parts for the existing generator just doesn't make
sense to me.
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
+1.340.998.9447 St. Thomas, VI 00802
Message 2
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: "Ron Davis" <l39parts@hotmail.com>
I can see how an 80 amp center-tap load would be a problem (on 24 AH
batteries). If I had that big of a 12 volt load, I'd try to split it into
two 40 amp loads like a 110/220 AC three wire system.(floating ground would
be necessary).
On the other hand a VHF comm on a 3 amp breaker and a transponder on a 5 amp
breaker (average combined load 1.7 amp) is unlikely to appreciably affect
the life of your two 12 lead acid batteries.
>From: Brian Lloyd <brianl@lloyd.com>
>Reply-To: yak-list@matronics.com
>To: yak-list@matronics.com
>Subject: Re: Yak-List: Battery Set Up
>Date: Thu, 16 Sep 2004 20:17:06 -0400
>
>--> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
>
>On Sep 14, 2004, at 11:26 PM, Frank Haertlein wrote:
>
> > Years ago, I deferred to Bryan Lloyd's suggestion of not tapping off
> > the
> > center of two 12V batteries in series as he had some doubts about
> > uneven
> > charging of the batteries in that configuration. I should have known
> > better and stuck with my original intention of tapping off the center
> > of
> > the two batteries. The trick with lead acid batteries is never to let
> > them discharge fully. Keep them near full charge and they last a very
> > long time. Basically, keep them near full capacity and I haven't had a
> > problem.
>
>I know I piss you off Frank, but when it comes to electrical systems,
>politics doesn't enter into it and I really do know what I am talking
>about.
>
>The problem with center tapping the batteries for your 14V loads is
>that the load draws down the lower battery which causes the upper
>battery to overcharge. Both batteries will then fail in short order,
>usually with the upper battery failing first. Trying to keep them
>charged up will just cause the upper battery to fail more quickly.
>
>Don't believe me? Ask Dennis Nickson. He used the center tap and
>destroyed two perfectly good sealed batteries in about 2 months.
>
>There is a device specifically to solve this problem. It is called a
>battery equalizer. It is a 28V to 14V converter that works by setting
>the 14V output to be exactly 1/2 of the 28V input. This keeps the
>charge on the batteries exactly equal. Now if you center tap your
>batteries to power your 14V loads, the equalizer will carry the load
>and keep the batteries equally charged. If the equalizer fails you
>will still have the juice in the lower battery but the two batteries
>will start to take an uneven charge will will quickly destroy them.
>
>I have found Surepower to be about the best source of battery
>equalizers. See: http://www.surepower.com/
>
>I have one of their 80A units in my boat to provide for my 14V loads
>from the center tap of my 500AH 24V battery bank. It works wonderfully
>and even deals with the slight difference in capacity between my
>batteries.
>
>Brian Lloyd 6501 Red Hook Plaza
>brianl@lloyd.com Suite 201
>+1.340.998.9447 St. Thomas, VI 00802
>
>
On the road to retirement? Check out MSN Life Events for advice on how to
get there! http://lifeevents.msn.com/category.aspx?cid=Retirement
Message 3
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
On Sep 22, 2004, at 10:34 AM, Ron Davis wrote:
> --> Yak-List message posted by: "Ron Davis" <l39parts@hotmail.com>
>
> I can see how an 80 amp center-tap load would be a problem (on 24 AH
> batteries). If I had that big of a 12 volt load, I'd try to split it
> into
> two 40 amp loads like a 110/220 AC three wire system.(floating ground
> would
> be necessary).
Well, I installed an 80A battery equalizer in my boat because I have a
worst-case 12V load of about 70A between the 150W HF transmitter, the
lighting, and the hydraulic pump for the autopilot steering, not things
you are likely to find in an aircraft. Also, my battery bank consists
of four 225AH gel-cells configured in series-parallel to provide 450AH
at 24V.
You can get battery equalizers with much smaller capacities that 80A.
Surepower's model 52102 24V/12V battery equalizer is rated at 10A,
probably just about perfect for a CJ6A. Here is the link to their
converter/equalizer brochure: http://www.surepower.com/pdf/ebr_dcdc.pdf
>
> On the other hand a VHF comm on a 3 amp breaker and a transponder on a
> 5 amp
> breaker (average combined load 1.7 amp) is unlikely to appreciably
> affect
> the life of your two 12 lead acid batteries.
I disagree. I watched exactly that configuration destroy both
batteries in Dennis Nickson's CJ6A in less than 2 months. If you doubt
me contact him. He reads this list but is out of town for a week or so
otherwise he would probably respond directly to the list.
Even a very small load on the 12V center tap will cause significant
overcharging of the top battery. With vented batteries you can get
away with it for a little while as long as you make a point of keeping
the top battery topped up with water and swap the batteries reasonably
often. If you try to do this with sealed batteries they will die a
quick death. They are dependent on the liberated O2 and H2 recombining
at the opposite plate and if you produce O2 and H2 too quickly, it just
escapes into the case, generating pressure without recombining.
Eventually the overpressure valve opens and vents the O2 and H2 to
atmosphere. The battery dries up and loses capacity after that.
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
+1.340.998.9447 St. Thomas, VI 00802
Message 4
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--> Yak-List message posted by: "Walt Lannon" <wlannon@cablerocket.com>
Michael;
Cable tensions for the CJ are not covered in the Technical Specifications
Manual. I believe they are in the Overhaul (Structural Repair) Manual. I
have a copy of this but it is in Chinese. As far as I know a translated
version is not available. If anyone knows otherwise please respond.
I digress! - Cable tensions -- Rig the rudder and elevator cable tension to
40 to 45 lbs at 20 degs.C and the trim cable to 5 to 10 Lbs. This is pretty
much standard for similar size cables and run lengths in other aircraft.
Walt
----- Original Message -----
From: "Beach, Michael (GE Energy)" <michael.beach@ps.ge.com>
Subject: RE: Yak-List: test
> --> Yak-List message posted by: "Beach, Michael (GE Energy)"
<michael.beach@ps.ge.com>
>
>
> Sorry to visit old ground but can any some one advise on the cable
> tensions for the CJ6 Rudder, elevator
> and trim tabs.
>
> Michael
>
>
Message 5
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
Brian,
I dont necessarily disagree with you with respect to the chemical reactions
that cause a battery to die, but if you draw a schematic of a single cell
battery (for simplicity's sake) and draw 2 in series, you will see that the
top battery's ground is the bottom battery's Positive side. The only
consequence I see from a small center load is that you create a floating
ground situation for the top battery. If the bottom battery is run down
appreciably more than the top battery, I would thing that you would just end
up with a ground reference lower than ground for the top batery. How this
would affect the battery when charging across the combined series load, I'm
unsure of. But I cant see how the top battery would be overcharged, I would
think that the top battery would leak back down towards ground to acheive
equilibrium.
Ernie
----- Original Message -----
From: "Brian Lloyd" <brianl@lloyd.com>
Subject: Re: Yak-List: Battery Set Up
> --> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
>
> On Sep 22, 2004, at 10:34 AM, Ron Davis wrote:
>
> > --> Yak-List message posted by: "Ron Davis" <l39parts@hotmail.com>
> >
> > I can see how an 80 amp center-tap load would be a problem (on 24 AH
> > batteries). If I had that big of a 12 volt load, I'd try to split it
> > into
> > two 40 amp loads like a 110/220 AC three wire system.(floating ground
> > would
> > be necessary).
>
> Well, I installed an 80A battery equalizer in my boat because I have a
> worst-case 12V load of about 70A between the 150W HF transmitter, the
> lighting, and the hydraulic pump for the autopilot steering, not things
> you are likely to find in an aircraft. Also, my battery bank consists
> of four 225AH gel-cells configured in series-parallel to provide 450AH
> at 24V.
>
> You can get battery equalizers with much smaller capacities that 80A.
> Surepower's model 52102 24V/12V battery equalizer is rated at 10A,
> probably just about perfect for a CJ6A. Here is the link to their
> converter/equalizer brochure: http://www.surepower.com/pdf/ebr_dcdc.pdf
>
> >
> > On the other hand a VHF comm on a 3 amp breaker and a transponder on a
> > 5 amp
> > breaker (average combined load 1.7 amp) is unlikely to appreciably
> > affect
> > the life of your two 12 lead acid batteries.
>
> I disagree. I watched exactly that configuration destroy both
> batteries in Dennis Nickson's CJ6A in less than 2 months. If you doubt
> me contact him. He reads this list but is out of town for a week or so
> otherwise he would probably respond directly to the list.
>
> Even a very small load on the 12V center tap will cause significant
> overcharging of the top battery. With vented batteries you can get
> away with it for a little while as long as you make a point of keeping
> the top battery topped up with water and swap the batteries reasonably
> often. If you try to do this with sealed batteries they will die a
> quick death. They are dependent on the liberated O2 and H2 recombining
> at the opposite plate and if you produce O2 and H2 too quickly, it just
> escapes into the case, generating pressure without recombining.
> Eventually the overpressure valve opens and vents the O2 and H2 to
> atmosphere. The battery dries up and loses capacity after that.
>
>
> Brian Lloyd 6501 Red Hook Plaza
> brianl@lloyd.com Suite 201
> +1.340.998.9447 St. Thomas, VI 00802
>
>
Message 6
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
Just as a floowup thought to my previous post.
Batteries have an internal resistance that varies with charge, as the lower
one is run down by the center tapped load, the internal resistance I beleive
increases, increasing the overall series resistance, i.e. 2 resistors in
series, the lower one being a rheostat. That increased resistance I would
think would then be the overall load to the charger. I dont understand how
the top battery would get a higher charge since the top battery's ground
potential is depedant on the bottom battery. Current would have to flow
through the bottom battery, thereby increasing the bottom battery's ground
reference with respect to the top battery.
Ernie
----- Original Message -----
From: "Ernie" <ernest.martinez@oracle.com>
Subject: Re: Yak-List: Battery Set Up
> --> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
>
> Brian,
>
> I dont necessarily disagree with you with respect to the chemical
reactions
> that cause a battery to die, but if you draw a schematic of a single cell
> battery (for simplicity's sake) and draw 2 in series, you will see that
the
> top battery's ground is the bottom battery's Positive side. The only
> consequence I see from a small center load is that you create a floating
> ground situation for the top battery. If the bottom battery is run down
> appreciably more than the top battery, I would thing that you would just
end
> up with a ground reference lower than ground for the top batery. How this
> would affect the battery when charging across the combined series load,
I'm
> unsure of. But I cant see how the top battery would be overcharged, I
would
> think that the top battery would leak back down towards ground to acheive
> equilibrium.
>
> Ernie
>
>
> ----- Original Message -----
> From: "Brian Lloyd" <brianl@lloyd.com>
> To: <yak-list@matronics.com>
> Subject: Re: Yak-List: Battery Set Up
>
>
> > --> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
> >
> > On Sep 22, 2004, at 10:34 AM, Ron Davis wrote:
> >
> > > --> Yak-List message posted by: "Ron Davis" <l39parts@hotmail.com>
> > >
> > > I can see how an 80 amp center-tap load would be a problem (on 24 AH
> > > batteries). If I had that big of a 12 volt load, I'd try to split it
> > > into
> > > two 40 amp loads like a 110/220 AC three wire system.(floating ground
> > > would
> > > be necessary).
> >
> > Well, I installed an 80A battery equalizer in my boat because I have a
> > worst-case 12V load of about 70A between the 150W HF transmitter, the
> > lighting, and the hydraulic pump for the autopilot steering, not things
> > you are likely to find in an aircraft. Also, my battery bank consists
> > of four 225AH gel-cells configured in series-parallel to provide 450AH
> > at 24V.
> >
> > You can get battery equalizers with much smaller capacities that 80A.
> > Surepower's model 52102 24V/12V battery equalizer is rated at 10A,
> > probably just about perfect for a CJ6A. Here is the link to their
> > converter/equalizer brochure: http://www.surepower.com/pdf/ebr_dcdc.pdf
> >
> > >
> > > On the other hand a VHF comm on a 3 amp breaker and a transponder on a
> > > 5 amp
> > > breaker (average combined load 1.7 amp) is unlikely to appreciably
> > > affect
> > > the life of your two 12 lead acid batteries.
> >
> > I disagree. I watched exactly that configuration destroy both
> > batteries in Dennis Nickson's CJ6A in less than 2 months. If you doubt
> > me contact him. He reads this list but is out of town for a week or so
> > otherwise he would probably respond directly to the list.
> >
> > Even a very small load on the 12V center tap will cause significant
> > overcharging of the top battery. With vented batteries you can get
> > away with it for a little while as long as you make a point of keeping
> > the top battery topped up with water and swap the batteries reasonably
> > often. If you try to do this with sealed batteries they will die a
> > quick death. They are dependent on the liberated O2 and H2 recombining
> > at the opposite plate and if you produce O2 and H2 too quickly, it just
> > escapes into the case, generating pressure without recombining.
> > Eventually the overpressure valve opens and vents the O2 and H2 to
> > atmosphere. The battery dries up and loses capacity after that.
> >
> >
> > Brian Lloyd 6501 Red Hook Plaza
> > brianl@lloyd.com Suite 201
> > +1.340.998.9447 St. Thomas, VI 00802
> >
> >
>
>
Message 7
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
On Sep 22, 2004, at 12:38 PM, Ernie wrote:
> --> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
>
> Brian,
>
> I dont necessarily disagree with you with respect to the chemical
> reactions
> that cause a battery to die, but if you draw a schematic of a single
> cell
> battery (for simplicity's sake) and draw 2 in series, you will see
> that the
> top battery's ground is the bottom battery's Positive side. The only
> consequence I see from a small center load is that you create a
> floating
> ground situation for the top battery. If the bottom battery is run down
> appreciably more than the top battery, I would thing that you would
> just end
> up with a ground reference lower than ground for the top batery. How
> this
> would affect the battery when charging across the combined series
> load, I'm
> unsure of. But I cant see how the top battery would be overcharged, I
> would
> think that the top battery would leak back down towards ground to
> acheive
> equilibrium.
Analyze the network using Kirchoff's law and you will begin the get the
picture. Treat the junction as a current node. A battery is a coulomb
tank. You will be putting a lot more coulombs into the top battery
than the bottom.
There is no guesswork in this and I am not theorizing. I know because
I have caused, fixed, and analyzed the problem.
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
+1.340.998.9447 St. Thomas, VI 00802
Message 8
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--> Yak-List message posted by: Walt Murphy <waltmurphy@charter.net>
Does anyone have Bill Blackwells shop phone number?
Thanks,
Walt
Message 9
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
On Sep 22, 2004, at 1:08 PM, Ernie wrote:
> --> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
>
> Batteries have an internal resistance that varies with charge, as the
> lower
> one is run down by the center tapped load, the internal resistance I
> beleive
> increases, increasing the overall series resistance, i.e. 2 resistors
> in
> series, the lower one being a rheostat. That increased resistance I
> would
> think would then be the overall load to the charger. I dont
> understand how
> the top battery would get a higher charge since the top battery's
> ground
> potential is depedant on the bottom battery. Current would have to flow
> through the bottom battery, thereby increasing the bottom battery's
> ground
> reference with respect to the top battery.
This is where Ohms law starts to break down. You are dealing with
multiple nodes, voltage sources, and multiple current paths. You have
to analyze this network using Kirchoff's laws.
Do you want me to go through the analysis? I don't really want to
spend the time and I don't have a chalkboard to work with here so I
would have to do it with ASCII art. That is time consuming.
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
+1.340.998.9447 St. Thomas, VI 00802
Message 10
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--> Yak-List message posted by: "Jim Selby" <alikatz@mbay.net>
I'll try and get that for you today.
Best,
Jim
----- Original Message -----
From: "Walt Murphy" <waltmurphy@charter.net>
Subject: Yak-List: Question
> --> Yak-List message posted by: Walt Murphy <waltmurphy@charter.net>
>
> Does anyone have Bill Blackwells shop phone number?
>
> Thanks,
> Walt
>
>
Message 11
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--> Yak-List message posted by: "Jim Selby" <alikatz@mbay.net>
Walt,
Here's Bill Blackwells Number.... 623-703-1001.
Best
Jim
----- Original Message -----
From: "Walt Murphy" <waltmurphy@charter.net>
Subject: Yak-List: Question
> --> Yak-List message posted by: Walt Murphy <waltmurphy@charter.net>
>
> Does anyone have Bill Blackwells shop phone number?
>
> Thanks,
> Walt
>
>
Message 12
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--> Yak-List message posted by: "Doug Sapp" <rvfltd@televar.com>
623-703-1001--Bill Blackwell, shop
Always Yakin,
Doug Sapp
-----Original Message-----
From: owner-yak-list-server@matronics.com
[mailto:owner-yak-list-server@matronics.com]On Behalf Of Jim Selby
Subject: Re: Yak-List: Question
--> Yak-List message posted by: "Jim Selby" <alikatz@mbay.net>
I'll try and get that for you today.
Best,
Jim
----- Original Message -----
From: "Walt Murphy" <waltmurphy@charter.net>
Subject: Yak-List: Question
> --> Yak-List message posted by: Walt Murphy <waltmurphy@charter.net>
>
> Does anyone have Bill Blackwells shop phone number?
>
> Thanks,
> Walt
>
>
Message 13
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
No thats fine. I was doing a litle research and we start dealing with Z as
opposed to R, which opens up a different can of worms. Even Kirchoffs law
doesnt deal with accurately since its dealing with single voltage sources or
multiple voltage sources with a common ground. When we deal with center
tapping battery's wired in series its analagous to going into a battery and
center tapping off of one of the plates.
Too much thinking for my damaged brain.
Ernie
----- Original Message -----
From: "Brian Lloyd" <brianl@lloyd.com>
Subject: Re: Yak-List: Battery Set Up
> --> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
>
> On Sep 22, 2004, at 1:08 PM, Ernie wrote:
>
> > --> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
> >
> > Batteries have an internal resistance that varies with charge, as the
> > lower
> > one is run down by the center tapped load, the internal resistance I
> > beleive
> > increases, increasing the overall series resistance, i.e. 2 resistors
> > in
> > series, the lower one being a rheostat. That increased resistance I
> > would
> > think would then be the overall load to the charger. I dont
> > understand how
> > the top battery would get a higher charge since the top battery's
> > ground
> > potential is depedant on the bottom battery. Current would have to flow
> > through the bottom battery, thereby increasing the bottom battery's
> > ground
> > reference with respect to the top battery.
>
> This is where Ohms law starts to break down. You are dealing with
> multiple nodes, voltage sources, and multiple current paths. You have
> to analyze this network using Kirchoff's laws.
>
> Do you want me to go through the analysis? I don't really want to
> spend the time and I don't have a chalkboard to work with here so I
> would have to do it with ASCII art. That is time consuming.
>
>
> Brian Lloyd 6501 Red Hook Plaza
> brianl@lloyd.com Suite 201
> +1.340.998.9447 St. Thomas, VI 00802
>
>
Message 14
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
On Sep 22, 2004, at 2:40 PM, Ernie wrote:
> --> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
>
> No thats fine. I was doing a litle research and we start dealing with
> Z as
> opposed to R, which opens up a different can of worms.
No, Z doesn't come into it as we are not dealing with AC. You can do
the entire analysis in DC.
> Even Kirchoffs law
> doesnt deal with accurately since its dealing with single voltage
> sources or
> multiple voltage sources with a common ground.
Kirchoff's law deals with it perfectly. It can handle a network of
multiple voltage sources (our two batteries and the alternator or
generator) and lots of resistances. That is what it is for. Remember,
the sum of the currents at any node is zero.
Work out the current flows for when the battery is half charged and
when it is approaching full charge. It will make it easier to figure
out of you assume 100% coulombic efficiency for the batteries under
charge and discharge (95% is closer to reality).
The strange stuff happens when you figure out what the current draw is
for each of the batteries at different states of discharge and
different applied voltages.
What you will see is that the lower battery will have lower and lower
applied voltage while the upper will have ever increasing applied
voltage. Also, the upper battery will always have the 12V load current
flowing through it no matter what its state of charge is. It will very
rapidly overcharge while the lower battery will discharge further and
further since it will not even achieve float charge voltage.
But the analysis starts with the current flows so you can quickly
calculate the state of charge of the two batteries.
> When we deal with center
> tapping battery's wired in series its analagous to going into a
> battery and
> center tapping off of one of the plates.
Remember a battery is just a bunch of cells in series. It doesn't
matter how you manage that.
>
> Too much thinking for my damaged brain.
Sorry about that.
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
+1.340.998.9447 St. Thomas, VI 00802
Message 15
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: "Jim Griffin" <jgriffint28@cox.net>
What you described is exactly what happened to my Chipmunk batteries. I
insisted that my mechanic install a 24 -12 V convertor and the problem was
solved. I had destroyed 2 new Gill batteries before I figured it out. Live
and learn
Jim Griffin
----- Original Message -----
From: "Brian Lloyd" <brianl@lloyd.com>
Subject: Re: Yak-List: Battery Set Up
> --> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
>
> On Sep 22, 2004, at 10:34 AM, Ron Davis wrote:
>
> > --> Yak-List message posted by: "Ron Davis" <l39parts@hotmail.com>
> >
> > I can see how an 80 amp center-tap load would be a problem (on 24 AH
> > batteries). If I had that big of a 12 volt load, I'd try to split it
> > into
> > two 40 amp loads like a 110/220 AC three wire system.(floating ground
> > would
> > be necessary).
>
> Well, I installed an 80A battery equalizer in my boat because I have a
> worst-case 12V load of about 70A between the 150W HF transmitter, the
> lighting, and the hydraulic pump for the autopilot steering, not things
> you are likely to find in an aircraft. Also, my battery bank consists
> of four 225AH gel-cells configured in series-parallel to provide 450AH
> at 24V.
>
> You can get battery equalizers with much smaller capacities that 80A.
> Surepower's model 52102 24V/12V battery equalizer is rated at 10A,
> probably just about perfect for a CJ6A. Here is the link to their
> converter/equalizer brochure: http://www.surepower.com/pdf/ebr_dcdc.pdf
>
> >
> > On the other hand a VHF comm on a 3 amp breaker and a transponder on a
> > 5 amp
> > breaker (average combined load 1.7 amp) is unlikely to appreciably
> > affect
> > the life of your two 12 lead acid batteries.
>
> I disagree. I watched exactly that configuration destroy both
> batteries in Dennis Nickson's CJ6A in less than 2 months. If you doubt
> me contact him. He reads this list but is out of town for a week or so
> otherwise he would probably respond directly to the list.
>
> Even a very small load on the 12V center tap will cause significant
> overcharging of the top battery. With vented batteries you can get
> away with it for a little while as long as you make a point of keeping
> the top battery topped up with water and swap the batteries reasonably
> often. If you try to do this with sealed batteries they will die a
> quick death. They are dependent on the liberated O2 and H2 recombining
> at the opposite plate and if you produce O2 and H2 too quickly, it just
> escapes into the case, generating pressure without recombining.
> Eventually the overpressure valve opens and vents the O2 and H2 to
> atmosphere. The battery dries up and loses capacity after that.
>
>
> Brian Lloyd 6501 Red Hook Plaza
> brianl@lloyd.com Suite 201
> +1.340.998.9447 St. Thomas, VI 00802
>
>
Message 16
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: cjpilot710@aol.com
Well, u's guys on this list are way beyond me!!!!!!! Ohms, Kirchoff law
(like in lawyer?) coulombic efficiency, Z vs R, differential applied voltages,
etc., etc.
All this happens when I flip a freq'n switch?
OR, am I see'n a "I'm smarter than you" todo? ;-)
Come on guys, give an old fart a brake.
Jim Goolsby
"They that can give up essential liberty to obtain a little safety, deserve
neither liberty nor safety"
Benjamin Franklin 1759
"The reason older men are like fine wine: when young, they are like grapes
until some woman stomps all over them."
Unknown older man.
"Kill them all. Let God sort them out"
Crusaders 900 AD
"With my shield, or on it."
Trojan Warriors, BC
Message 17
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
Ok I'll simplify it for you.
You see this lil ole finigin pin needs to hold the left handed wind shifter
here just right, otherwise the knoozermombilizer gets all disconfribulated.
Ernie
----- Original Message -----
From: <cjpilot710@aol.com>
Subject: Re: Yak-List: Battery Set Up
> --> Yak-List message posted by: cjpilot710@aol.com
>
>
> Well, u's guys on this list are way beyond me!!!!!!! Ohms, Kirchoff law
> (like in lawyer?) coulombic efficiency, Z vs R, differential applied
voltages,
> etc., etc.
>
> All this happens when I flip a freq'n switch?
>
> OR, am I see'n a "I'm smarter than you" todo? ;-)
>
> Come on guys, give an old fart a brake.
>
> Jim Goolsby
>
> "They that can give up essential liberty to obtain a little safety,
deserve
> neither liberty nor safety"
> Benjamin Franklin 1759
>
> "The reason older men are like fine wine: when young, they are like grapes
> until some woman stomps all over them."
> Unknown older man.
>
> "Kill them all. Let God sort them out"
> Crusaders 900 AD
>
> "With my shield, or on it."
> Trojan Warriors, BC
>
>
Message 18
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--> Yak-List message posted by: "Graeme Frew" <gfrew@attglobal.net>
Steve Hanshew I lost your address in a microsoft/McAfee conspired crash. Can you
contact me off list please.
Cheers
Graeme Frew
Message 19
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| Subject: | Re: Generator vs. Alternator (Was: Voltage Regs) |
--> Yak-List message posted by: "Graeme Frew" <gfrew@attglobal.net>
As I've explained previously I don't want to spend the money replacing the
original system. From my research of the popular alternatives on this here
web group it was still in the region of $700-$1000 U.S. to fit an
alternator. That's a considerable amount in Pacific Pesos (N.Z Dollars)
All I was after, and thought I'd purchased was a replacement of the old
carbon pile voltage regulator which is the bit at fault. I don't care much
about the size and weight my aim was to unbolt the faulty part and install a
serviceable one and viola. It was a nice theory but instead I have ended up
with a completely different system which is why I was asking for information
about these solid state versions and whether they are interchangeable.
I hope this furthers your understanding. If I was keeping the aeroplane I
would definitely be looking at an alternator.
Graeme Frew
Nanchang 01 'there can be only one'
Message 20
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: Brian Lloyd <brianl@lloyd.com>
On Sep 22, 2004, at 4:11 PM, cjpilot710@aol.com wrote:
> --> Yak-List message posted by: cjpilot710@aol.com
>
>
> Well, u's guys on this list are way beyond me!!!!!!! Ohms, Kirchoff
> law
> (like in lawyer?) coulombic efficiency, Z vs R, differential applied
> voltages,
> etc., etc.
Yeah, fun.
> All this happens when I flip a freq'n switch?
Uh huh.
> OR, am I see'n a "I'm smarter than you" todo? ;-)
Not so much. It is more of a, "and I *really* do know what I am
talking about here," thing. There are a lot of opinions floating
around and I want to make the point that this is not a matter of
opinion but of clearly understood science.
FYI:
A coulomb is a bucket of electrons. Think of it as a gallon of
electrons, OK? One amp is one coulomb per second. Amps are your "burn
rate". A 30AH battery holds 108,000 coulombs (C). If a battery has
100% coulombic efficiency then when you suck out 100C you need put back
only 100C to recharge it. Most batteries are less efficient than that
so when you suck out 95C you have to put back 100C to recharge them.
In this 12V-center-tap discussion you look at where the current is
going and you find that you pull more coulombs out of the bottom
battery during discharge and put more into the top battery during
recharge. Also, unlike a normal battery that stops accepting current
when it is finally recharged the top battery is forced to keep
accepting coulombs by virtue of the 12V load. It will very quickly
overcharge and damage itself unless the 12V load is *really* small.
>
> Come on guys, give an old fart a brake.
Aw Pappy, you can handle it.
Brian Lloyd 6501 Red Hook Plaza
brianl@lloyd.com Suite 201
+1.340.998.9447 St. Thomas, VI 00802
Message 21
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--> Yak-List message posted by: cjpilot710@aol.com
I am redoing my cockpits.
So out goes the old stuff.
Now what is one man's -er (well not junk), is another man's treasure.
I have for sale.
One - Inverter
Two - 21/4" tachometer indicators.
Two - Horizons (BDP-2) 1 is good the other unknown.
One - TH-3 gyro. that the 'coffee can' behind the front seat.
One - Magnetometer. (that big blue sucker out in the wing).
Two - YRK-1 Magentic Direction indicators
One - Altimeter (meters of course)
Two - Manifold Pressure gages.
One - airspeed indicator. Km/h
One - ADF instrument gage
These parts have been in the airplane for the 9 nine years I've owned it.
I have put 1,100 hours personally on these items.
No guaranties of course.
Money back if it don't work.
You pay the shipping and a very small pittance.
Come one! Come all! "Honest Jim" will be happy to serve you.
Contact me off list. I guess that's the best way to do this.
Jim Goolsby
"They that can give up essential liberty to obtain a little safety, deserve
neither liberty nor safety"
Benjamin Franklin 1759
"The reason older men are like fine wine: when young, they are like grapes
until some woman stomps all over them."
Unknown older man.
"Kill them all. Let God sort them out"
Crusaders 900 AD
"With my shield, or on it."
Trojan Warriors, BC
Message 22
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| Subject: | Re: Skyfest 2004...Last Call |
--> Yak-List message posted by: Bpx2horn@aol.com
Bill,
I will be bringing my yak down to Cincinnati prior to Sky Fest and leaving
on Thursday afternoon or Friday morning. Do you want to meet up.
Paul Hornick
815-547-1430 Hm
859-250-3200 Cl
Message 23
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| Subject: | Re: Battery Set Up |
--> Yak-List message posted by: Mike Brogley <mikebrogley@ieee.org>
Graham Chapman: Trouble at t'mill.
Carol Cleveland: Oh no - what kind of trouble?
Chapman: One on't cross beams gone owt askew on treddle.
Cleveland: Pardon?
Chapman: One on't cross beams gone owt askew on treddle.
Cleveland: I don't understand what you're saying.
Chapman: (slightly irritatedly and with exaggeratedly clear accent)
One of the cross beams has gone out askew on the treddle.
Cleveland: Well what on earth does that mean?
Chapman: *I* don't know - Mr Wentworth just told me to come in here and say
that there was trouble at the mill, that's all - I didn't expect a
kind of Spanish Inquisition.
(JARRING CHORD)
(The door flies open and Cardinal Ximinez of Spain (Palin) enters, flanked by
two junior cardinals. Cardinal Biggles (Jones) has goggles pushed over his
forehead. Cardinal Fang (Gilliam) is just Cardinal Fang)
Ximinez: NOBODY expects the Spanish Inquisition! Our chief weapon is
suprise...surprise and fear...fear and surprise.... Our two
weapons are fear and surprise...and ruthless efficiency.... Our
*three* weapons are fear, surprise, and ruthless efficiency...and an
almost fanatical devotion to the Pope.... Our *four*...no...
*Amongst* our weapons.... Amongst our weaponry...are such elements as
fear, surprise.... I'll come in again.
--
Mike
Ernie wrote:
>--> Yak-List message posted by: "Ernie" <ernest.martinez@oracle.com>
>
>Ok I'll simplify it for you.
>
>You see this lil ole finigin pin needs to hold the left handed wind shifter
>here just right, otherwise the knoozermombilizer gets all disconfribulated.
>
>Ernie
>----- Original Message -----
>From: <cjpilot710@aol.com>
>To: <yak-list@matronics.com>
>Subject: Re: Yak-List: Battery Set Up
>
>
>
>
>>--> Yak-List message posted by: cjpilot710@aol.com
>>
>>
>>Well, u's guys on this list are way beyond me!!!!!!! Ohms, Kirchoff law
>>(like in lawyer?) coulombic efficiency, Z vs R, differential applied
>>
>>
>voltages,
>
>
>>etc., etc.
>>
>>All this happens when I flip a freq'n switch?
>>
>>OR, am I see'n a "I'm smarter than you" todo? ;-)
>>
>>Come on guys, give an old fart a brake.
>>
>>Jim Goolsby
>>
>>"They that can give up essential liberty to obtain a little safety,
>>
>>
>deserve
>
>
>>neither liberty nor safety"
>>Benjamin Franklin 1759
>>
>>"The reason older men are like fine wine: when young, they are like grapes
>>until some woman stomps all over them."
>>Unknown older man.
>>
>>"Kill them all. Let God sort them out"
>>Crusaders 900 AD
>>
>>"With my shield, or on it."
>>Trojan Warriors, BC
>>
>>
>>
>>
>
>
>
>
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