Today's Message Index:
----------------------
0. 12:15 AM - PLEASE READ - List Fund Raiser Kickoff! (Matt Dralle)
1. 04:09 AM - Re: Amp Meter (DaveG601XL)
2. 05:55 AM - Re: Re: Amp Meter (FLYaDIVE)
3. 09:38 AM - Re: Amp Meter (DaveG601XL)
4. 10:42 AM - Re: Re: Amp Meter (FLYaDIVE)
5. 11:26 AM - Re: Re: Amp Meter (FLYaDIVE)
6. 03:28 PM - AMP METER & SHUNT (FLYaDIVE)
Message 0
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | PLEASE READ - List Fund Raiser Kickoff! |
Dear Listers,
Each November I hold a PBS-like fund raiser to support the continued operation
and upgrade of the List services at Matronics. It's solely through the Contributions
of List members that these Matronics Lists are possible. There is NO
advertising to support the Lists. You might have noticed the conspicuous lack
of flashing banners and annoying pop-ups on the Matronics Email List email messages
and web site pages including:
* Matronics List Forums http://forums.matronics.com
* Matronics List List Wiki http://wiki.matronics.com
* Matronics List Search Engine http://www.matronics.com/search
* Matronics List Browser http://www.matronics.com/listbrowse
You don't find advertising on any of these pages because I believe in a List experience
that is completely about the sport we all enjoy - namely Airplanes and
not about annoying advertisements.
During the month of November I will be sending out List messages every couple of
days reminding everyone that the Fund Raiser is underway. I ask for your patience
and understanding during the Fund Raiser and throughout these regular messages.
The Fund Raiser is only financial support mechanism I have to pay all
of the bills associated with running these Lists. Your personal Contribution
counts!
Once again, this year I've got a terrific line up of free gifts to go along with
the various Contribution levels. Most all of these gifts have been provided
by some of the vary members and vendors that you'll find on Matronics Lists and
have been either donated or provided at substantially discounted rates.
This year, these generous people include:
* Bob Nuckolls of the AeroElectric Connection http://www.aeroelectric.com
* Andy Gold of the Builder's Bookstore http://www.buildersbooks.com
* Jon Croke of HomebuiltHELP http://www.homebuilthelp.com
These are extremely generous guys and I encourage you to visit their respective
web sites. Each one offers a unique and very useful aviation-related product
line. I would like publicly to thank Bob, Andy, and Jon for their generous support
of the Lists again this year!!
You can make your List Contribution using any one of three secure methods including
using a credit card, PayPal, or by personal check. All three methods afford
you the opportunity to select one of this year's free gifts with a qualifying
Contribution amount!!
To make your Contribution, please visit the secure site below:
http://www.matronics.com/contribution
I would like to thank everyone in advance for their generous financial AND moral
support over the years!
Matt Dralle
Matronics Email List Administrator
RV-8 Builder and Flyer
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
My Jabiru/Dynon D180 shunt is on the primary feed wire right before the main bus.
This makes it is a load meter with a 0-20 amp type reading. Looking at the
attached plot in the short term (point-to-point), shows about a +/- 2 amp variation
or noise in amperage. I don't know what other aircraft ammeter plots
look like, but I consider this an acceptable amount of variation for my aircraft.
As has already been asked, where in the electrical circuit is your shunt?
I assume it is in one of the three locations suggested in the Dynon install
manual.
Good luck,
--------
David Gallagher
601 XL/Jabiru 3300
First flight 7/24/08
Upgraded 3/19/10
150+ hours and climbing!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=317726#317726
Attachments:
http://forums.matronics.com//files/voltsamps_184.jpg
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
David:
Your terminology is a bit askew.
A LOAD meter is a device that calculates the Voltage and the Amperage and
gives a Wattage. YET! I have seen the wattage terminology left off and
Amps substituted.
Putting an ammeter in series with the battery will show the amperage/current
flowing to or from the the battery. Your 0 - 20 Amp meter will show ONLY
current going to the Buss. You require two conditions to show + & -
current:
1 - A meter with the capability of displaying + & - current (Zero Center
Meter - Analog or a Digital - Circuit to do the sensing) and
2 - The output from the alternator to be BEFORE the Amp Meter.
That way it will show current going TO the Battery - Charge State. Or FROM
the Battery - Discharge State.
I missed the "plot" you are referring to ... Did you or someone graph a
charge - discharge condition? What is this "noise" you are referring to, is
that your terminology? I have never heard of amperage referred to as noise?
Voltage, YES!
But, I get the feeling that you are referring to the Idle State of your
electrical system. What it requires without any additional components
turned on. Just the state of Master Contactor closed & Alternator charging,
am I close?
Barry
On Mon, Nov 1, 2010 at 7:06 AM, DaveG601XL <david.m.gallagher@ge.com> wrote:
> david.m.gallagher@ge.com>
>
> My Jabiru/Dynon D180 shunt is on the primary feed wire right before the
> main bus. This makes it is a load meter with a 0-20 amp type reading.
> Looking at the attached plot in the short term (point-to-point), shows
> about a +/- 2 amp variation or noise in amperage. I don't know what other
> aircraft ammeter plots look like, but I consider this an acceptable amount
> of variation for my aircraft. As has already been asked, where in the
> electrical circuit is your shunt? I assume it is in one of the three
> locations suggested in the Dynon install manual.
>
> Good luck,
>
> --------
> David Gallagher
> 601 XL/Jabiru 3300
> First flight 7/24/08
> Upgraded 3/19/10
> 150+ hours and climbing!
>
>
Message 3
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
Barry,
Not being an electrical expert, I can only aspire to try and correctly interpret
terminology from those who are. An example being from Bob Nuckolls Aeroelectric
Digest "Loadmeters only read 0 to some value either in amps full scale (or
in the case of the ones I sell, 0-100% of alternator output)." That is about
as deep as I can describe a loadmeter.
Terminology aside, my configuration of metering the load is that I only show the
+ amperage going to my aircraft loads. As opposed to two other shunt locations
that would show (1) +- flow in and out of the battery or (2) + only, but going
to both aircraft loads and the battery.
--------
David Gallagher
601 XL/Jabiru 3300
First flight 7/24/08
Upgraded 3/19/10
160+ hours and climbing!
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=317763#317763
Message 4
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
Hi David;
You do not require two shunts. Only one shunt and a meter capable of
reading both Positive and Negative current flow.
If I may, let me describe what a SHUNT is and why it is required.
A SHUNT is exactly what the word says it is... "A way around",
"To circumvent" as in a Shun-pike - A way around a pike.
Why are there shunts? It is not practicable to manufacture an AMMETER for
ever current range required by different applications. So, there are some
basic Ammeters at basic current levels: 100 uA. 1 mA, 100 mA & 1 A.
The SHUNT is placed in PARALLEL with the above ammeter(s) to divert the HIGH
current around the Meter, while allowing the small amount through the meter.
For example:-
If you wanted to read 10 Amps you may use a 1 Amp Meter with a SHUNT capable
of carrying 9 Amps.
The meter reads 0 to 1 and that would be 0 to 10 Amps with the shunt
installed.
How is the value of the shunt determined?
By RESISTANCE.
If the Meter has an internal resistance of say 100 Ohms the Shunt must carry
a ratio of (X):
1 Amp is to 10 Amps
as
100 Ohms is to X Ohms
X being 0.1
Or 0.1 Ohms
The direction of the current does not mater, NOT to the shunt... Only to the
Meter.
On Mon, Nov 1, 2010 at 12:35 PM, DaveG601XL <david.m.gallagher@ge.com>wrote:
> david.m.gallagher@ge.com>
>
> Barry,
>
> Not being an electrical expert, I can only aspire to try and correctly
> interpret terminology from those who are. An example being from Bob
> Nuckolls Aeroelectric Digest "Loadmeters only read 0 to some value either in
> amps full scale (or in the case of the ones I sell, 0-100% of alternator
> output)." That is about as deep as I can describe a loadmeter.
>
> Terminology aside, my configuration of metering the load is that I only
> show the + amperage going to my aircraft loads. As opposed to two other
> shunt locations that would show (1) +- flow in and out of the battery or (2)
> + only, but going to both aircraft loads and the battery.
>
> --------
> David Gallagher
> 601 XL/Jabiru 3300
> First flight 7/24/08
> Upgraded 3/19/10
> 160+ hours and climbing!
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=317763#317763
>
>
--
Barry
"Chop'd Liver"
Message 5
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
Whoops...
Sorry Gaggle - The email got away from me. Before I was finished.
I'll finish up and resend it.
Barry
On Mon, Nov 1, 2010 at 1:39 PM, FLYaDIVE <flyadive@gmail.com> wrote:
> Hi David;
>
> You do not require two shunts. Only one shunt and a meter capable of
> reading both Positive and Negative current flow.
>
> If I may, let me describe what a SHUNT is and why it is required.
> A SHUNT is exactly what the word says it is... "A way around",
> "To circumvent" as in a Shun-pike - A way around a pike.
> Why are there shunts? It is not practicable to manufacture an AMMETER for
> ever current range required by different applications. So, there are some
> basic Ammeters at basic current levels: 100 uA. 1 mA, 100 mA & 1 A.
> The SHUNT is placed in PARALLEL with the above ammeter(s) to divert the
> HIGH current around the Meter, while allowing the small amount through the
> meter.
> For example:-
> If you wanted to read 10 Amps you may use a 1 Amp Meter with a SHUNT
> capable of carrying 9 Amps.
> The meter reads 0 to 1 and that would be 0 to 10 Amps with the shunt
> installed.
>
> How is the value of the shunt determined?
> By RESISTANCE.
> If the Meter has an internal resistance of say 100 Ohms the Shunt must
> carry a ratio of (X):
> 1 Amp is to 10 Amps
> as
> 100 Ohms is to X Ohms
> X being 0.1
> Or 0.1 Ohms
>
> The direction of the current does not mater, NOT to the shunt... Only to
> the Meter.
>
>
> On Mon, Nov 1, 2010 at 12:35 PM, DaveG601XL <david.m.gallagher@ge.com>wrote:
>
>> david.m.gallagher@ge.com>
>>
>> Barry,
>>
>> Not being an electrical expert, I can only aspire to try and correctly
>> interpret terminology from those who are. An example being from Bob
>> Nuckolls Aeroelectric Digest "Loadmeters only read 0 to some value either in
>> amps full scale (or in the case of the ones I sell, 0-100% of alternator
>> output)." That is about as deep as I can describe a loadmeter.
>>
>> Terminology aside, my configuration of metering the load is that I only
>> show the + amperage going to my aircraft loads. As opposed to two other
>> shunt locations that would show (1) +- flow in and out of the battery or (2)
>> + only, but going to both aircraft loads and the battery.
>>
>> --------
>> David Gallagher
>> 601 XL/Jabiru 3300
>> First flight 7/24/08
>> Upgraded 3/19/10
>> 160+ hours and climbing!
>>
>>
>>
>>
>> Read this topic online here:
>>
>> http://forums.matronics.com/viewtopic.php?p=317763#317763
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>
>
> --
> Barry
> "Chop'd Liver"
>
>
--
Barry
"Chop'd Liver"
Message 6
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | AMP METER & SHUNT |
Hi David;
You do not require two shunts. Only one shunt and a meter capable of
reading both Positive and Negative current flow.
If I may, let me describe what a SHUNT is and why it is required.
A SHUNT is exactly what the word says it is... "A way around",
"To circumvent" as in a Shun-pike - A way around a pike.
Why are there shunts? It is not practicable to manufacture an AMMETER for
ever current range required by different applications. So, there are some
basic Ammeters at basic current levels: 100 uA. 1 mA, 100 mA & 1 A.
The SHUNT is placed in PARALLEL with the above ammeter(s) to divert the HIGH
current around the Meter, while allowing the small amount through the meter.
For example:-
If you wanted to read 10 Amps you may use a 1 Amp Meter with a SHUNT capable
of carrying 9 Amps.
The meter reads 0 to 1 and that would be 0 to 10 Amps with the shunt
installed.
How is the value of the shunt determined?
By RESISTANCE.
If the Meter has an internal resistance of say 100 Ohms the Shunt must carry
a ratio of (X):
1 Amp is to 100 Ohms
as
9 Amps is to X Ohms
---> WHY 9 AMPS? Because since the Shunt is in Parallel with the 1 Amp
meter ...
1 Amp goes through the meter and 9 amps goes through the shunt. A total of a
10 Amp flow.
100 / 9 = 11.11 Ohms for the SHUNT value.
Now I arbitrarily picked 100 Ohms and 1 Amp for the meter.
The real value of the meter would probably be closer to 12 Ohms.
Now, You Can Not just put a DMM across a meter to find the resistance.
Because the DMM would load down the meter and give an incorrect reading.
This would be indicated by a deflection of the ammeter needle. OF COURSE -
If the amperage of the un-shunted meter was high enough there would be less
loading of the DMM.
Did this confuse ya? I could go more in depth if anyone is interested :-(
One more NOW - The direction of the current does not mater, NOT to the
shunt... Dave, you do NOT need anymore than ONE SHUNT. The direction
ONLY mater to the Meter.
OK, DONE - - - Phew!
--
Barry
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|