Re: Stus-List Battery test

[Della Barba, Joe via CnC-List]

We were usually testing really big banks. You are correct a lower rate will be 
more accurate for smaller batteries.
This is just a very rough test anyway, there are sophisticated conductance 
meters and meters that keep track of amp-hours used that are better. If you use 
what should be half the capacity and the battery ends up dead, you know it is 
beat.
Joe
Coquina
From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Rick Brass 
via CnC-List
Sent: Tuesday, February 07, 2017 19:54
To: cnc-list@cnc-list.com
Cc: Rick Brass <rickbr...@earthlink.net>
Subject: Re: Stus-List Battery test

Joe;

Not to be argumentative, but the Amp Hour rating for a battery is by definition 
based on the current the battery will provide that results in it being fully 
discharged over 20 hours. For a typical 12 volt group 27 or 31 battery in the 
100 AH range, that's about 5 amps of current. For a 4D or 8D you might be in 
the in the 10A range. For a set of 4 GC5 golf cart batteries wired to be a 12v 
bank at 480AH, maybe 24A.

Deep cycle batteries typically have the AH rating on the label. So you could 
take the total of the AH ratings for the bank you want to test (My house bank 
happens to be 4x115=460AH when new. ) divide by 20 and get the current flow 
that you want to use as to measure your AH capacity. Then discharge the battery 
to 50% as you suggest (about 10 hours, give or take a bit) and you can 
calculate the AH capacity you have.

Regarding your suggestion to use a 20A discharge rate, by definition the 
Reserve Capacity of a battery is the number of minutes that a battery will 
deliver 25 amps of current before being fully discharged. That's because a 
typical automobile uses about 25A of current to run the ignition, lights, 
wipers, and other essential systems (not the air conditioner, GPS, or stereo). 
The reserve Capacity is intended to tell you how long you have to get to the 
mechanic after you have a failed alternator or a broken alternator belt. A 
typical BCI 27 automotive battery with about 100AH rating would typically have 
something like 160 minutes reserve capacity. 25Ax2.67hr=66.75AH - far less than 
the AH rating of the battery because of Peukert's Law and the impact of 
discharging at the higher rate. AmpHour capacity and Reserve Capacity are not 
the same thing

The real AH capacity of a battery bank decreases over time; with each 
discharge/charge cycle of the battery the capacity decreases slightly. I 
already indicated in a earlier post that my house bank (460AH when installed in 
2010) is down to about 400AH based on the information from my LinkLite.

Len, you indicated that your boat already has a Link battery monitor. If you 
fully charge the battery, "synchronize" the monitor, open the circuit from the 
solar panels to take them out of the system, and then wait a few hours you can 
get the information needed to calculate the total AH capacity of the bank when 
you "synchronized" the meter. You just need the total for amp hours used and 
the percentage of capacity remaining to do the arithmetic.

I wonder why you are looking for another method?

Rick Brass
Washington, NC


From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Della Barba, 
Joe via CnC-List
Sent: Tuesday, February 07, 2017 10:15 AM
To: 'cnc-list@cnc-list.com' 
<cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com>>
Cc: Della Barba, Joe <joe.della.ba...@ssa.gov<mailto:joe.della.ba...@ssa.gov>>
Subject: Re: Stus-List Battery test

Easy cheap way.
If you have accurate volt and amp meters,  a 20 amp (or near enough) load 
applied for enough time to drain the batteries 50%*. You should see 12.2 for 
wet cells and 12.3 or so for gel/agm.
Light loads like 1-5 amps and heavy loads like 50-100 amps both will be 
inaccurate because of Peukert's law. This law deals with the fact that  a 100 
AH battery can supply 100 amps for 1 hour or 1 amp for 100 hours in theory, but 
in practice 1 amp will last longer than 100 hours and 100 amps won't make the 
full hour. 20 amps is a good value for these tests.

* (AH capacity of batteries/load in amps) /2 = time in hours for 50% discharge

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Russ & 
Melody via CnC-List
Sent: Tuesday, February 07, 2017 00:41
To: cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com>
Cc: Russ & Melody <russ...@telus.net<mailto:russ...@telus.net>>
Subject: Re: Stus-List Battery test

Hi Len,

If you're 100 percent full and have a coffee in your hand, may I suggest some 
advice from Bobby... and words I live by.

Don't warry. Be Happy.

Cheers, Russ
Sweet 35 mk-1



At 07:28 PM 06/02/2017, you wrote:
I think the CBA would work well so far from the little reading I have done. I 
have four 6 volt deep cycle batteries for my house bank and a Link monitor. I 
also have a simple analogue load tester. The problem is the solar panel mas

Re: Stus-List Battery test

[Michael Brown via CnC-List]

Some background:

http://4xspower.com/wp-content/uploads/2010/01/bci-ohmicreadings.pdf

Michael Brown
Windburn
C 30-1



From: Josh Muckley  

I'd like to know more about the technology, how it works, and how accurate 
it is. 
 
Josh Muckley 
S/V Sea Hawk 
1989 C 37+ 
Solomons, MD 
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make a contribution to offset our costs, please go to:  
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Re: Stus-List Battery test

[Frederick G Street via CnC-List]

Josh — try this:

http://www.skylark.co.uk/CONDUCTANCEQ-A.htm 


— Fred

Fred Street -- Minneapolis
S/V Oceanis (1979 C Landfall 38) -- on the hard in Bayfield, WI   :^(

> On Feb 7, 2017, at 6:54 PM, Josh Muckley via CnC-List  
> wrote:
> 
> I'd like to know more about the technology, how it works, and how accurate it 
> is.
> 
> Josh Muckley
> S/V Sea Hawk
> 1989 C 37+
> Solomons, MD
> 
> On Feb 7, 2017 6:45 PM, "Frederick G Street via CnC-List" 
> > wrote:
> I think I’ll stick with my Midtronics conductive tester; good, accurate 
> results on the health of my golf-cart and start batteries, it only takes a 
> minute, and no chance of starting things on fire…   :^)
> 
> Fred Street -- Minneapolis
> S/V Oceanis (1979 C Landfall 38) -- on the hard in Bayfield, WI   :^(

___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Michael Brown via CnC-List]

> Typically batteries are only considered at their end of life until they 
> only test at 50% of original labeled capacity.

A rough guess for a marine deep cycle battery is that during a Reserve Capacity
test if the under load voltage drops to 11v at less that half the run time the
battery has less than 50% of the original capacity.

> There is no need to go full discharge.

If the battery is in known good shape you can extrapolate the capacity from a
partial discharge.  A defective battery may still work correctly and follow a
normal discharge curve for a while, then rapidly it's voltage will fall off.

Sort of like the "Discharge curve of SLA batteries" from here:

http://www.steveduncan.net/html/discharge_testing_slas.html

Testing those three batteries for 15 minutes would yield similar results, but
only one battery has full capacity.

Which is what you are saying with your junk batteries.

So in some cases going to full discharge may make sense.


Michael Brown
Windburn
C 30-1




From: Josh Muckley <muckl...@gmail.com> 
 
There is no need to go full discharge.  The voltage and capacity properties 
of a lead-acid battery have a near linear relationship so a 50% discharge 
is fine for testing.  That should be 11.6v.  All of this is just a 
comparison.  A brand new battery might show +/- 10% of the labeled rating. 
That doesn't mean that you got a good or bad battery.  It's just an 
indication of how difficult it is to accurately measure the capacity. 
Typically batteries are only considered at their end of life until they 
only test at 50% of original labeled capacity.  Capacity tests really are 
most powerful as a trending and comparison measurement rather than a 
go/no-go.  I've successfully used 100Ah batteries that measured at only 
7Ah.  I know they are junk but keep them around for various workbench 
projects.  I've even used them to successfully start my spare marine diesel 
sitting in the garage. 
 
Josh Muckley 
S/V Sea Hawk 
1989 C 37+ 
Solomons, MD 
 
On Feb 7, 2017 5:09 PM, "Michael Brown via CnC-List" <cnc-list@cnc-list.com> 
wrote: 
 
> If you have the original battery Reserve Capacity specs it is an 
> acceptable quick test 
> to see if the battery is good but maybe worn or at end of life. 
> 
> If possible test the battery(s) individually, Charge fully, bring battery 
> to around 80F and 
> time how long it will sustain a 25 amp load before reaching 10.5v. Note 
> that takes the 
> battery to almost complete discharge and may significantly shorten it's 
> life. If the voltage 
> gets to 11.0v and the time is less than half the RC spec there is not much 
> to be gained 
> testing further, the battery is worn out. 
> 
> The 10.5v sounds pretty bad but that is an under load voltage and is 
> different from an 
> at rest voltage. 
> 
> Michael Brown 
> Windburn 
> C 30-1 
> 
> 
> 
> ___ 
> 
> This list is supported by the generous donations of our members. If you 
> wish to make a contribution to offset our costs, please go to: 
> https://www.paypal.me/stumurray 
> 
> All Contributions are greatly appreciated! 
> 
> 
-- next part -- 
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------ 
 
Message: 4 
Date: Tue, 7 Feb 2017 17:44:53 -0600 
From: Frederick G Street <f...@postaudio.net> 
To: cnc-list@cnc-list.com 
Subject: Re: Stus-List Battery test 
Message-ID: <31218ecf-62be-4a0e-83ec-552d052b5...@postaudio.net> 
Content-Type: text/plain; charset="utf-8" 
 
I think I?ll stick with my Midtronics conductive tester; good, accurate results 
on the health of my golf-cart and start batteries, it only takes a minute, and 
no chance of starting things on fire?   :^) 
 
Fred Street -- Minneapolis 
S/V Oceanis (1979 C Landfall 38) -- on the hard in Bayfield, WI   :^( 
 
> On Feb 7, 2017, at 4:52 PM, Josh Muckley via CnC-List <cnc-list@cnc-list.com> 
> wrote: 
>  
> There is no need to go full discharge.  The voltage and capacity properties 
> of a lead-acid battery have a near linear relationship so a 50% discharge is 
> fine for testing.  That should be 11.6v.  All of this is just a comparison.  
> A brand new battery might show +/- 10% of the labeled rating.  That doesn't 
> mean that you got a good or bad battery.  It's just an indication of how 
> difficult it is to accurately measure the capacity.  Typically batteries are 
> only considered at their end of life until they only test at 50% of original 
> labeled capacity.  Capacity tests really are most powerful as a trending and 
> comparison measurement rather than a go/no-go.  I've successfully used 100Ah 
> batteries that measured at on

Re: Stus-List Battery test

[Josh Muckley via CnC-List]

I'd like to know more about the technology, how it works, and how accurate
it is.

Josh Muckley
S/V Sea Hawk
1989 C 37+
Solomons, MD

On Feb 7, 2017 6:45 PM, "Frederick G Street via CnC-List" <
cnc-list@cnc-list.com> wrote:

> I think I’ll stick with my Midtronics conductive tester; good, accurate
> results on the health of my golf-cart and start batteries, it only takes a
> minute, and no chance of starting things on fire…   :^)
>
> Fred Street -- Minneapolis
> S/V Oceanis (1979 C Landfall 38) -- on the hard in Bayfield, WI   :^(
>
> On Feb 7, 2017, at 4:52 PM, Josh Muckley via CnC-List <
> cnc-list@cnc-list.com> wrote:
>
> There is no need to go full discharge.  The voltage and capacity
> properties of a lead-acid battery have a near linear relationship so a 50%
> discharge is fine for testing.  That should be 11.6v.  All of this is just
> a comparison.  A brand new battery might show +/- 10% of the labeled
> rating.  That doesn't mean that you got a good or bad battery.  It's just
> an indication of how difficult it is to accurately measure the capacity.
> Typically batteries are only considered at their end of life until they
> only test at 50% of original labeled capacity.  Capacity tests really are
> most powerful as a trending and comparison measurement rather than a
> go/no-go.  I've successfully used 100Ah batteries that measured at only
> 7Ah.  I know they are junk but keep them around for various workbench
> projects.  I've even used them to successfully start my spare marine diesel
> sitting in the garage.
>
> Josh Muckley
> S/V Sea Hawk
> 1989 C 37+
> Solomons, MD
>
>
>
> ___
>
> This list is supported by the generous donations of our members. If you
> wish to make a contribution to offset our costs, please go to:
> https://www.paypal.me/stumurray
>
> All Contributions are greatly appreciated!
>
>
___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Rick Brass via CnC-List]

Joe;

 

Not to be argumentative, but the Amp Hour rating for a battery is by
definition based on the current the battery will provide that results in it
being fully discharged over 20 hours. For a typical 12 volt group 27 or 31
battery in the 100 AH range, that's about 5 amps of current. For a 4D or 8D
you might be in the in the 10A range. For a set of 4 GC5 golf cart batteries
wired to be a 12v bank at 480AH, maybe 24A.

 

Deep cycle batteries typically have the AH rating on the label. So you could
take the total of the AH ratings for the bank you want to test (My house
bank happens to be 4x115=460AH when new. ) divide by 20 and get the current
flow that you want to use as to measure your AH capacity. Then discharge the
battery to 50% as you suggest (about 10 hours, give or take a bit) and you
can calculate the AH capacity you have.

 

Regarding your suggestion to use a 20A discharge rate, by definition the
Reserve Capacity of a battery is the number of minutes that a battery will
deliver 25 amps of current before being fully discharged. That's because a
typical automobile uses about 25A of current to run the ignition, lights,
wipers, and other essential systems (not the air conditioner, GPS, or
stereo). The reserve Capacity is intended to tell you how long you have to
get to the mechanic after you have a failed alternator or a broken
alternator belt. A typical BCI 27 automotive battery with about 100AH rating
would typically have something like 160 minutes reserve capacity.
25Ax2.67hr=66.75AH - far less than the AH rating of the battery because of
Peukert's Law and the impact of discharging at the higher rate. AmpHour
capacity and Reserve Capacity are not the same thing

 

The real AH capacity of a battery bank decreases over time; with each
discharge/charge cycle of the battery the capacity decreases slightly. I
already indicated in a earlier post that my house bank (460AH when installed
in 2010) is down to about 400AH based on the information from my LinkLite.

 

Len, you indicated that your boat already has a Link battery monitor. If you
fully charge the battery, "synchronize" the monitor, open the circuit from
the solar panels to take them out of the system, and then wait a few hours
you can get the information needed to calculate the total AH capacity of the
bank when you "synchronized" the meter. You just need the total for amp
hours used and the percentage of capacity remaining to do the arithmetic.

 

I wonder why you are looking for another method?

 

Rick Brass

Washington, NC

 

 

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Della
Barba, Joe via CnC-List
Sent: Tuesday, February 07, 2017 10:15 AM
To: 'cnc-list@cnc-list.com' <cnc-list@cnc-list.com>
Cc: Della Barba, Joe <joe.della.ba...@ssa.gov>
Subject: Re: Stus-List Battery test

 

Easy cheap way.
If you have accurate volt and amp meters,  a 20 amp (or near enough) load
applied for enough time to drain the batteries 50%*. You should see 12.2 for
wet cells and 12.3 or so for gel/agm.

Light loads like 1-5 amps and heavy loads like 50-100 amps both will be
inaccurate because of Peukert's law. This law deals with the fact that  a
100 AH battery can supply 100 amps for 1 hour or 1 amp for 100 hours in
theory, but in practice 1 amp will last longer than 100 hours and 100 amps
won't make the full hour. 20 amps is a good value for these tests.

 

* (AH capacity of batteries/load in amps) /2 = time in hours for 50%
discharge

 

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Russ &
Melody via CnC-List
Sent: Tuesday, February 07, 2017 00:41
To: cnc-list@cnc-list.com <mailto:cnc-list@cnc-list.com> 
Cc: Russ & Melody <russ...@telus.net <mailto:russ...@telus.net> >
Subject: Re: Stus-List Battery test

 

Hi Len,

If you're 100 percent full and have a coffee in your hand, may I suggest
some advice from Bobby... and words I live by.

Don't warry. Be Happy.

Cheers, Russ
Sweet 35 mk-1



At 07:28 PM 06/02/2017, you wrote:

I think the CBA would work well so far from the little reading I have done.
I have four 6 volt deep cycle batteries for my house bank and a Link
monitor. I also have a simple analogue load tester. The problem is the solar
panel masks any shortfall in the bank by fully charging usually before I
make coffee in the morning. The house bank isn't quite as full on a rainy
day and everything works but I would like to know how well. I probably
should just leave it alone but if the bank is 100% charged but at 50% amp
hour capacity I want to know. Len

___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Frederick G Street via CnC-List]

I think I’ll stick with my Midtronics conductive tester; good, accurate results 
on the health of my golf-cart and start batteries, it only takes a minute, and 
no chance of starting things on fire…   :^)

Fred Street -- Minneapolis
S/V Oceanis (1979 C Landfall 38) -- on the hard in Bayfield, WI   :^(

> On Feb 7, 2017, at 4:52 PM, Josh Muckley via CnC-List  
> wrote:
> 
> There is no need to go full discharge.  The voltage and capacity properties 
> of a lead-acid battery have a near linear relationship so a 50% discharge is 
> fine for testing.  That should be 11.6v.  All of this is just a comparison.  
> A brand new battery might show +/- 10% of the labeled rating.  That doesn't 
> mean that you got a good or bad battery.  It's just an indication of how 
> difficult it is to accurately measure the capacity.  Typically batteries are 
> only considered at their end of life until they only test at 50% of original 
> labeled capacity.  Capacity tests really are most powerful as a trending and 
> comparison measurement rather than a go/no-go.  I've successfully used 100Ah 
> batteries that measured at only 7Ah.  I know they are junk but keep them 
> around for various workbench projects.  I've even used them to successfully 
> start my spare marine diesel sitting in the garage.
> 
> Josh Muckley
> S/V Sea Hawk
> 1989 C 37+
> Solomons, MD

___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Josh Muckley via CnC-List]

There is no need to go full discharge.  The voltage and capacity properties
of a lead-acid battery have a near linear relationship so a 50% discharge
is fine for testing.  That should be 11.6v.  All of this is just a
comparison.  A brand new battery might show +/- 10% of the labeled rating.
That doesn't mean that you got a good or bad battery.  It's just an
indication of how difficult it is to accurately measure the capacity.
Typically batteries are only considered at their end of life until they
only test at 50% of original labeled capacity.  Capacity tests really are
most powerful as a trending and comparison measurement rather than a
go/no-go.  I've successfully used 100Ah batteries that measured at only
7Ah.  I know they are junk but keep them around for various workbench
projects.  I've even used them to successfully start my spare marine diesel
sitting in the garage.

Josh Muckley
S/V Sea Hawk
1989 C 37+
Solomons, MD

On Feb 7, 2017 5:09 PM, "Michael Brown via CnC-List" 
wrote:

> If you have the original battery Reserve Capacity specs it is an
> acceptable quick test
> to see if the battery is good but maybe worn or at end of life.
>
> If possible test the battery(s) individually, Charge fully, bring battery
> to around 80F and
> time how long it will sustain a 25 amp load before reaching 10.5v. Note
> that takes the
> battery to almost complete discharge and may significantly shorten it's
> life. If the voltage
> gets to 11.0v and the time is less than half the RC spec there is not much
> to be gained
> testing further, the battery is worn out.
>
> The 10.5v sounds pretty bad but that is an under load voltage and is
> different from an
> at rest voltage.
>
> Michael Brown
> Windburn
> C 30-1
>
>
>
> ___
>
> This list is supported by the generous donations of our members. If you
> wish to make a contribution to offset our costs, please go to:
> https://www.paypal.me/stumurray
>
> All Contributions are greatly appreciated!
>
>
___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Michael Brown via CnC-List]

If you have the original battery Reserve Capacity specs it is an acceptable 
quick test
to see if the battery is good but maybe worn or at end of life.

If possible test the battery(s) individually, Charge fully, bring battery to 
around 80F and
time how long it will sustain a 25 amp load before reaching 10.5v. Note that 
takes the
battery to almost complete discharge and may significantly shorten it's life. 
If the voltage
gets to 11.0v and the time is less than half the RC spec there is not much to 
be gained
testing further, the battery is worn out.

The 10.5v sounds pretty bad but that is an under load voltage and is different 
from an
at rest voltage.

Michael Brown
Windburn
C 30-1


___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Della Barba, Joe via CnC-List]

Cool page :)
This is the relevant one:
http://batteryuniversity.com/learn/article/how_to_measure_capacity


From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of BillBinaList 
via CnC-List
Sent: Tuesday, February 07, 2017 16:49
To: cnc-list@cnc-list.com
Cc: BillBinaList <billbinal...@gmail.com>
Subject: Re: Stus-List Battery test


http://batteryuniversity.com/

Bill Bina

On 2/7/2017 4:37 PM, Della Barba, Joe via CnC-List wrote:
Load test is not a CAPACITY test - not at ALL.
My start battery is a 35 AH gel cell and it reads very well with my 100A load 
tester or the engine starter, which is 125 amps or so.
Joe
Coquina
(used to be a dealer for Penn Deka batteries)

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Jerome 
Tauber via CnC-List
Sent: Tuesday, February 07, 2017 14:19
To: cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com>
Cc: Jerome Tauber <jrtau...@aol.com><mailto:jrtau...@aol.com>
Subject: Re: Stus-List Battery test

The starter motor can be used for a load test.  Just measure the voltage across 
the battery terminals while cranking. performs a basic load-test of the 
battery, using the vehicle's starter motor. This test is done with the engine 
cranking. Use care to keep the voltmeter test leads from contacting moving or 
hot engine parts.

Tool required: Digital Voltmeter, set on DC Volts

Test Lead position: across battery terminals.

While cranking, read the voltmeter. If the voltage reading is below the minimum 
listed in the following chart, replace the battery.

Be aware that other possible causes of low readings in this test are a failing 
starter motor or an engine with mechanical problems.

Minimum Battery Load-test Voltage



Battery Temp Degrees F


9.90


100


9.80


90


9.70


80


9.60


70


9.50


60


9.40


50


9.30


40


9.10


30


8.90


20


8.70


10


8.50
[page2image39984]


0



Sent from my iPhone




___



This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray



All Contributions are greatly appreciated!

___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[BillBinaList via CnC-List]

http://batteryuniversity.com/

Bill Bina


On 2/7/2017 4:37 PM, Della Barba, Joe via CnC-List wrote:


Load test is not a CAPACITY test – not at ALL.

My start battery is a 35 AH gel cell and it reads very well with my 
100A load tester or the engine starter, which is 125 amps or so.


Joe

Coquina

(used to be a dealer for Penn Deka batteries)

*From:*CnC-List [mailto:cnc-list-boun...@cnc-list.com] *On Behalf Of 
*Jerome Tauber via CnC-List

*Sent:* Tuesday, February 07, 2017 14:19
*To:* cnc-list@cnc-list.com
*Cc:* Jerome Tauber <jrtau...@aol.com>
*Subject:* Re: Stus-List Battery test

The starter motor can be used for a load test.  Just measure the 
voltage across the battery terminals while cranking. performs a basic 
load-test of the battery, using the vehicle’s starter motor. This test 
is done with the engine cranking. Use care to keep the voltmeter test 
leads from contacting moving or hot engine parts.


Tool required: Digital Voltmeter, set on DC Volts

Test Lead position: across battery terminals.

While cranking, read the voltmeter. If the voltage reading is
below the minimum listed in the following chart, replace the battery.

Be aware that other possible causes of low readings in this test
are a failing starter motor or an engine with mechanical problems.

Minimum Battery Load-test Voltage



page2image10120page2image10880

Battery Temp Degrees F

9.90



100

9.80



90

9.70



80

9.60



70

9.50



60

9.40



50

9.30



40

9.10



30

8.90



20

8.70



10

8.50

page2image39984



0

Sent from my iPhone



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make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

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make a contribution to offset our costs, please go to:  
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All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Della Barba, Joe via CnC-List]

Load test is not a CAPACITY test – not at ALL.
My start battery is a 35 AH gel cell and it reads very well with my 100A load 
tester or the engine starter, which is 125 amps or so.
Joe
Coquina
(used to be a dealer for Penn Deka batteries)

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Jerome 
Tauber via CnC-List
Sent: Tuesday, February 07, 2017 14:19
To: cnc-list@cnc-list.com
Cc: Jerome Tauber <jrtau...@aol.com>
Subject: Re: Stus-List Battery test

The starter motor can be used for a load test.  Just measure the voltage across 
the battery terminals while cranking. performs a basic load-test of the 
battery, using the vehicle’s starter motor. This test is done with the engine 
cranking. Use care to keep the voltmeter test leads from contacting moving or 
hot engine parts.

Tool required: Digital Voltmeter, set on DC Volts

Test Lead position: across battery terminals.

While cranking, read the voltmeter. If the voltage reading is below the minimum 
listed in the following chart, replace the battery.

Be aware that other possible causes of low readings in this test are a failing 
starter motor or an engine with mechanical problems.

Minimum Battery Load-test Voltage



Battery Temp Degrees F


9.90


100


9.80


90


9.70


80


9.60


70


9.50


60


9.40


50


9.30


40


9.10


30


8.90


20


8.70


10


8.50
[page2image39984]


0



Sent from my iPhone
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make a contribution to offset our costs, please go to:  
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Re: Stus-List Battery test

[Della Barba, Joe via CnC-List]

Load testing and capacity testing are very different things. The 100 amp load 
tester is a rough guide to the cranking power of the battery, not the AH 
capacity. My 35 AH gel start battery reads very well on that meter. You don't 
use it for long ;)
Joe
Coquina

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Bill Bina - 
gmail via CnC-List
Sent: Tuesday, February 07, 2017 14:12
To: cnc-list@cnc-list.com' <cnc-list@cnc-list.com>
Cc: Bill Bina - gmail <billbinal...@gmail.com>
Subject: Re: Stus-List Battery test


Read the instructions! This is how most of the world, including your local 
battery dealer, load tests batteries. LOL

Bill Bina

On 2/7/2017 2:06 PM, Della Barba, Joe wrote:
I have one of those. It draws 5 times the current desired AND would likely 
catch on fire or burn something up if left on for long. It is a 1200 watt 
heater with no fan!
Joe
Coquina

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Bill Bina - 
gmail via CnC-List
Sent: Tuesday, February 07, 2017 12:07
To: cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com>
Cc: Bill Bina - gmail <billbinal...@gmail.com><mailto:billbinal...@gmail.com>
Subject: Re: Stus-List Battery test


http://www.harborfreight.com/100-amp-612v-battery-load-tester-61747.html

Bill Bina

On 2/7/2017 11:54 AM, Ron Ricci via CnC-List wrote:
Dave,

If you used a resistor, you'd need 0.6 ohms at least 240 watts.  Probably not 
practical.  You could put a load on your batteries by turning on most of your 
lights, cabin fans and other loads.

Ron

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of David Knecht 
via CnC-List
Sent: Tuesday, February 7, 2017 11:32 AM
To: CnC CnC discussion list
Cc: David Knecht
Subject: Re: Stus-List Battery test

I have been following this discussion and would like to do this for my 
batteries.  Can you suggest what would be an easy/appropriate ~20A load 
generating device?  Dave

Aries
1990 C 34+
New London, CT

[cid:image001.png@01D28138.02844420]

.

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make a contribution to offset our costs, please go to:  
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Re: Stus-List Battery test

[Jerome Tauber via CnC-List]

> The starter motor can be used for a load test.  Just measure the voltage 
> across the battery terminals while cranking. performs a basic load-test of 
> the battery, using the vehicle’s starter motor. This test is done with the 
> engine cranking. Use care to keep the voltmeter test leads from contacting 
> moving or hot engine parts.
> Tool required: Digital Voltmeter, set on DC Volts
> 
> Test Lead position: across battery terminals.  
> 
> While cranking, read the voltmeter. If the voltage reading is below the 
> minimum listed in the following chart, replace the battery.
> 
> Be aware that other possible causes of low readings in this test are a 
> failing starter motor or an engine with mechanical problems.
> 
> Minimum Battery Load-test Voltage
> 
>   
> Battery Temp Degrees F
> 
> 9.90
> 
> 100
> 
> 9.80
> 
> 90
> 
> 9.70
> 
> 80
> 
> 9.60
> 
> 70
> 
> 9.50
> 
> 60
> 
> 9.40
> 
> 50
> 
> 9.30
> 
> 40
> 
> 9.10
> 
> 30
> 
> 8.90
> 
> 20
> 
> 8.70
> 
> 10
> 
> 8.50
> 
>   
> 0
> 
> 
> 
> 
> Sent from my iPhone
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Re: Stus-List Battery test

[Jerome Tauber via CnC-List]

The starter motor can be used for a load test. 

STEP 2 of 3

STEP 2 performs a basic load-test of the battery, using the vehicle’s starter 
motor. This test is done with the engine cranking. Use care to keep the 
voltmeter test leads from contacting moving or hot engine parts.

Tool required: Digital Voltmeter, set on DC Volts

Test Lead position: as shown in diagram above

While cranking, read the voltmeter. If the voltage reading is below the minimum 
listed in the following chart, replace the battery.

Be aware that other possible causes of low readings in this test are a failing 
starter motor or an engine with mechanical problems.

Minimum Battery Load-test Voltage


Battery Temp Degrees F

9.90

100

9.80

90

9.70

80

9.60

70

9.50

60

9.40

50

9.30

40

9.10

30

8.90

20

8.70

10

8.50


0




Sent from my iPhone___

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make a contribution to offset our costs, please go to:  
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All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Bill Bina - gmail via CnC-List]

Read the instructions! This is how most of the world, including your 
local battery dealer, load tests batteries. LOL


Bill Bina


On 2/7/2017 2:06 PM, Della Barba, Joe wrote:


I have one of those. It draws 5 times the current desired AND would 
likely catch on fire or burn something up if left on for long. It is a 
1200 watt heater with no fan!


Joe

Coquina

*From:*CnC-List [mailto:cnc-list-boun...@cnc-list.com] *On Behalf Of 
*Bill Bina - gmail via CnC-List

*Sent:* Tuesday, February 07, 2017 12:07
*To:* cnc-list@cnc-list.com
*Cc:* Bill Bina - gmail <billbinal...@gmail.com>
*Subject:* Re: Stus-List Battery test

http://www.harborfreight.com/100-amp-612v-battery-load-tester-61747.html

Bill Bina

On 2/7/2017 11:54 AM, Ron Ricci via CnC-List wrote:

Dave,

If you used a resistor, you’d need 0.6 ohms at least 240 watts. 
Probably not practical.  You could put a load on your batteries by

turning on most of your lights, cabin fans and other loads.

Ron

*From:*CnC-List [mailto:cnc-list-boun...@cnc-list.com] *On Behalf
Of *David Knecht via CnC-List
*Sent:* Tuesday, February 7, 2017 11:32 AM
*To:* CnC CnC discussion list
*Cc:* David Knecht
*Subject:* Re: Stus-List Battery test

I have been following this discussion and would like to do this
for my batteries.  Can you suggest what would be an
easy/appropriate ~20A load generating device?  Dave

Aries
1990 C 34+
New London, CT

cid:image001.png@01D28138.02844420

.



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make a contribution to offset our costs, please go to:  
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Re: Stus-List Battery test

[Della Barba, Joe via CnC-List]

I have one of those. It draws 5 times the current desired AND would likely 
catch on fire or burn something up if left on for long. It is a 1200 watt 
heater with no fan!
Joe
Coquina

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Bill Bina - 
gmail via CnC-List
Sent: Tuesday, February 07, 2017 12:07
To: cnc-list@cnc-list.com
Cc: Bill Bina - gmail <billbinal...@gmail.com>
Subject: Re: Stus-List Battery test


http://www.harborfreight.com/100-amp-612v-battery-load-tester-61747.html

Bill Bina

On 2/7/2017 11:54 AM, Ron Ricci via CnC-List wrote:
Dave,

If you used a resistor, you'd need 0.6 ohms at least 240 watts.  Probably not 
practical.  You could put a load on your batteries by turning on most of your 
lights, cabin fans and other loads.

Ron

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of David Knecht 
via CnC-List
Sent: Tuesday, February 7, 2017 11:32 AM
To: CnC CnC discussion list
Cc: David Knecht
Subject: Re: Stus-List Battery test

I have been following this discussion and would like to do this for my 
batteries.  Can you suggest what would be an easy/appropriate ~20A load 
generating device?  Dave

Aries
1990 C 34+
New London, CT

[cid:image001.png@01D28138.02844420]

.
___

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make a contribution to offset our costs, please go to:  
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Re: Stus-List Battery test

[Della Barba, Joe via CnC-List]

I would just turn on lights until I got to around 20 amps. You can get 100 watt 
12 volt bulbs at West < 
https://www.westmarine.com/buy/ancor--standard-screw-base-bulbs--P009_276_006_521?recordNum=3>.
 2 or 3 of those would do.
For a temporary setup, a standard cheap halogen car headlight is usually about 
55 watts on low and 60/65 on high. Two of those running high and low beam would 
work. You do not have to be exactly at 20 amps, 15 or 25 will do. What you do 
need to do is set a timer to go down and turn them off at the 50% point and you 
need to be able to measure the amps to get this right. This is NOT going to be 
exact, but it should roughly tell you if you are near the stock capacity.
Here is something to watch: I bought a new gel in January and it seemed to go 
dead very fast. I returned it and the shop tested it with good results. Back to 
the boat and it sucked again.
??
The temp sensor circuit on my charger had died and it was getting summer charge 
settings. I got a new battery charger that could properly sense battery temps 
and the battery was fine once it was charged appropriately for cold weather.

Joe
Coquina



From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Ron Ricci 
via CnC-List
Sent: Tuesday, February 07, 2017 11:55
To: cnc-list@cnc-list.com
Cc: Ron Ricci <rvri...@gmail.com>
Subject: Re: Stus-List Battery test

Dave,

If you used a resistor, you’d need 0.6 ohms at least 240 watts.  Probably not 
practical.  You could put a load on your batteries by turning on most of your 
lights, cabin fans and other loads.

Ron

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of David Knecht 
via CnC-List
Sent: Tuesday, February 7, 2017 11:32 AM
To: CnC CnC discussion list
Cc: David Knecht
Subject: Re: Stus-List Battery test

I have been following this discussion and would like to do this for my 
batteries.  Can you suggest what would be an easy/appropriate ~20A load 
generating device?  Dave

Aries
1990 C 34+
New London, CT

[cid:image001.png@01D28138.02844420]

On Feb 7, 2017, at 10:15 AM, Della Barba, Joe via CnC-List 
<cnc-list@cnc-list.com<mailto:cnc-list@cnc-list.com>> wrote:

Easy cheap way.
If you have accurate volt and amp meters,  a 20 amp (or near enough) load 
applied for enough time to drain the batteries 50%*. You should see 12.2 for 
wet cells and 12.3 or so for gel/agm.
Light loads like 1-5 amps and heavy loads like 50-100 amps both will be 
inaccurate because of Peukert’s law. This law deals with the fact that  a 100 
AH battery can supply 100 amps for 1 hour or 1 amp for 100 hours in theory, but 
in practice 1 amp will last longer than 100 hours and 100 amps won’t make the 
full hour. 20 amps is a good value for these tests.

* (AH capacity of batteries/load in amps) /2 = time in hours for 50% discharge

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make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

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Re: Stus-List Battery test

[Bill Bina - gmail via CnC-List]

http://www.harborfreight.com/100-amp-612v-battery-load-tester-61747.html

Bill Bina


On 2/7/2017 11:54 AM, Ron Ricci via CnC-List wrote:


Dave,

If you used a resistor, you’d need 0.6 ohms at least 240 watts.  
Probably not practical.  You could put a load on your batteries by 
turning on most of your lights, cabin fans and other loads.


Ron

*From:*CnC-List [mailto:cnc-list-boun...@cnc-list.com] *On Behalf Of 
*David Knecht via CnC-List

*Sent:* Tuesday, February 7, 2017 11:32 AM
*To:* CnC CnC discussion list
*Cc:* David Knecht
*Subject:* Re: Stus-List Battery test

I have been following this discussion and would like to do this for my 
batteries.  Can you suggest what would be an easy/appropriate ~20A 
load generating device?  Dave


Aries
1990 C 34+
New London, CT

cid:image001.png@01D28138.02844420



.
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make a contribution to offset our costs, please go to:  
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Re: Stus-List Battery test

[Ron Ricci via CnC-List]

Dave,

 

If you used a resistor, you’d need 0.6 ohms at least 240 watts.  Probably not 
practical.  You could put a load on your batteries by turning on most of your 
lights, cabin fans and other loads.  

 

Ron

 

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of David Knecht 
via CnC-List
Sent: Tuesday, February 7, 2017 11:32 AM
To: CnC CnC discussion list
Cc: David Knecht
Subject: Re: Stus-List Battery test

 

I have been following this discussion and would like to do this for my 
batteries.  Can you suggest what would be an easy/appropriate ~20A load 
generating device?  Dave

 

Aries
1990 C 34+
New London, CT

cid:image001.png@01D28138.02844420





On Feb 7, 2017, at 10:15 AM, Della Barba, Joe via CnC-List 
<cnc-list@cnc-list.com> wrote:

Easy cheap way.
If you have accurate volt and amp meters,  a 20 amp (or near enough) load 
applied for enough time to drain the batteries 50%*. You should see 12.2 for 
wet cells and 12.3 or so for gel/agm.
Light loads like 1-5 amps and heavy loads like 50-100 amps both will be 
inaccurate because of Peukert’s law. This law deals with the fact that  a 100 
AH battery can supply 100 amps for 1 hour or 1 amp for 100 hours in theory, but 
in practice 1 amp will last longer than 100 hours and 100 amps won’t make the 
full hour. 20 amps is a good value for these tests.
 
* (AH capacity of batteries/load in amps) /2 = time in hours for 50% discharge

 

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make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Petar Horvatic via CnC-List]

Now that its winter as shown in pbase articles, provided that you have 
disconnected each of your batteries prior to winter storage so your batteries 
can reach steady state, you could just go and measure the voltage on each one 
and get a very reliable State of charge.  And you would do it without 
sacrificing the one cycle (20A 50% discharge test).  Lead acids are usually 
estimated at 300 cycles with 50% discharge, assuming you properly charge and 
don’t leave them discharged for long time.   

 

Battery monitors will tell you state of charge(SOC) based on how many AH left 
and how many you put back.  So that’s pretty accurate.On top of it you can 
add the Peukert’s exponent stuff to account for losses and you can set cutoffs 
for battery type.   

The problem is you can damage batteries by overcharging or keeping them empty 
for too long. If that takes place, then SOC as shown by the monitor is no 
longer reliable.  

 

 

Petar Horvatic

Sundowner

76 C 38MkII

On the hard at Stanleys in barrington

 

 

 

 

 

 

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Marek 
Dziedzic via CnC-List
Sent: Tuesday, February 07, 2017 11:23 AM
To: cnc-list@cnc-list.com
Cc: Marek Dziedzic
Subject: Re: Stus-List Battery test

 

Len,

 

there is no free lunch... (i.e. if you do it cheap or quickly, the results will 
be questionable).

 

Joe’s way is probably the best way to do it, provided that you can maintain a 
steady 20 A current through the load and that you can stop the discharge at the 
particular voltage level (you have to watch it).

 

I would suggest looking up this web site: 
http://www.pbase.com/mainecruising/boat_projects and specifically, this 
article: http://www.pbase.com/mainecruising/battery_state_of_charge.

 

This should give you plenty of advice.

 

You would also find that the battery monitors, usually, just measure the 
current flowing out of the battery (batteries) and potentially, the voltage. So 
they might tell you how much charge you have used, but they won’t tell you the 
SoC of the battery.

 

good luck 

 

Marek

 

 

From: Della Barba, Joe via CnC-List 

Sent: Tuesday, February 7, 2017 10:16

To: cnc-list@cnc-list.com 

Cc: Della Barba, Joe 

Subject: Re: Stus-List Battery test

 

Easy cheap way.
If you have accurate volt and amp meters,  a 20 amp (or near enough) load 
applied for enough time to drain the batteries 50%*. You should see 12.2 for 
wet cells and 12.3 or so for gel/agm.

Light loads like 1-5 amps and heavy loads like 50-100 amps both will be 
inaccurate because of Peukert’s law. This law deals with the fact that  a 100 
AH battery can supply 100 amps for 1 hour or 1 amp for 100 hours in theory, but 
in practice 1 amp will last longer than 100 hours and 100 amps won’t make the 
full hour. 20 amps is a good value for these tests.

 

* (AH capacity of batteries/load in amps) /2 = time in hours for 50% discharge

 

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Russ & 
Melody via CnC-List
Sent: Tuesday, February 07, 2017 00:41
To: cnc-list@cnc-list.com
Cc: Russ & Melody <russ...@telus.net>
Subject: Re: Stus-List Battery test

 

Hi Len,

If you're 100 percent full and have a coffee in your hand, may I suggest some 
advice from Bobby... and words I live by.

Don't warry. Be Happy.

Cheers, Russ
Sweet 35 mk-1



At 07:28 PM 06/02/2017, you wrote:

I think the CBA would work well so far from the little reading I have done. I 
have four 6 volt deep cycle batteries for my house bank and a Link monitor. I 
also have a simple analogue load tester. The problem is the solar panel masks 
any shortfall in the bank by fully charging usually before I make coffee in the 
morning. The house bank isn't quite as full on a rainy day and everything works 
but I would like to know how well. I probably should just leave it alone but if 
the bank is 100% charged but at 50% amp hour capacity I want to know. Len

___

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make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[David Knecht via CnC-List]

I have been following this discussion and would like to do this for my 
batteries.  Can you suggest what would be an easy/appropriate ~20A load 
generating device?  Dave

Aries
1990 C 34+
New London, CT


> On Feb 7, 2017, at 10:15 AM, Della Barba, Joe via CnC-List 
>  wrote:
> 
> Easy cheap way.
> If you have accurate volt and amp meters,  a 20 amp (or near enough) load 
> applied for enough time to drain the batteries 50%*. You should see 12.2 for 
> wet cells and 12.3 or so for gel/agm.
> Light loads like 1-5 amps and heavy loads like 50-100 amps both will be 
> inaccurate because of Peukert’s law. This law deals with the fact that  a 100 
> AH battery can supply 100 amps for 1 hour or 1 amp for 100 hours in theory, 
> but in practice 1 amp will last longer than 100 hours and 100 amps won’t make 
> the full hour. 20 amps is a good value for these tests.
>  
> * (AH capacity of batteries/load in amps) /2 = time in hours for 50% discharge

___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Marek Dziedzic via CnC-List]

Len,

there is no free lunch... (i.e. if you do it cheap or quickly, the results will 
be questionable).

Joe’s way is probably the best way to do it, provided that you can maintain a 
steady 20 A current through the load and that you can stop the discharge at the 
particular voltage level (you have to watch it).

I would suggest looking up this web site: 
http://www.pbase.com/mainecruising/boat_projects and specifically, this 
article: http://www.pbase.com/mainecruising/battery_state_of_charge.

This should give you plenty of advice.

You would also find that the battery monitors, usually, just measure the 
current flowing out of the battery (batteries) and potentially, the voltage. So 
they might tell you how much charge you have used, but they won’t tell you the 
SoC of the battery.

good luck

Marek


From: Della Barba, Joe via CnC-List
Sent: Tuesday, February 7, 2017 10:16
To: cnc-list@cnc-list.com
Cc: Della Barba, Joe
Subject: Re: Stus-List Battery test

Easy cheap way.
If you have accurate volt and amp meters,  a 20 amp (or near enough) load 
applied for enough time to drain the batteries 50%*. You should see 12.2 for 
wet cells and 12.3 or so for gel/agm.
Light loads like 1-5 amps and heavy loads like 50-100 amps both will be 
inaccurate because of Peukert’s law. This law deals with the fact that  a 100 
AH battery can supply 100 amps for 1 hour or 1 amp for 100 hours in theory, but 
in practice 1 amp will last longer than 100 hours and 100 amps won’t make the 
full hour. 20 amps is a good value for these tests.

* (AH capacity of batteries/load in amps) /2 = time in hours for 50% discharge

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Russ & 
Melody via CnC-List
Sent: Tuesday, February 07, 2017 00:41
To: cnc-list@cnc-list.com
Cc: Russ & Melody <russ...@telus.net>
Subject: Re: Stus-List Battery test

Hi Len,

If you're 100 percent full and have a coffee in your hand, may I suggest some 
advice from Bobby... and words I live by.

Don't warry. Be Happy.

Cheers, Russ
Sweet 35 mk-1



At 07:28 PM 06/02/2017, you wrote:

I think the CBA would work well so far from the little reading I have done. I 
have four 6 volt deep cycle batteries for my house bank and a Link monitor. I 
also have a simple analogue load tester. The problem is the solar panel masks 
any shortfall in the bank by fully charging usually before I make coffee in the 
morning. The house bank isn't quite as full on a rainy day and everything works 
but I would like to know how well. I probably should just leave it alone but if 
the bank is 100% charged but at 50% amp hour capacity I want to know. Len
___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Della Barba, Joe via CnC-List]

Easy cheap way.
If you have accurate volt and amp meters,  a 20 amp (or near enough) load 
applied for enough time to drain the batteries 50%*. You should see 12.2 for 
wet cells and 12.3 or so for gel/agm.
Light loads like 1-5 amps and heavy loads like 50-100 amps both will be 
inaccurate because of Peukert's law. This law deals with the fact that  a 100 
AH battery can supply 100 amps for 1 hour or 1 amp for 100 hours in theory, but 
in practice 1 amp will last longer than 100 hours and 100 amps won't make the 
full hour. 20 amps is a good value for these tests.

* (AH capacity of batteries/load in amps) /2 = time in hours for 50% discharge

From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Russ & 
Melody via CnC-List
Sent: Tuesday, February 07, 2017 00:41
To: cnc-list@cnc-list.com
Cc: Russ & Melody <russ...@telus.net>
Subject: Re: Stus-List Battery test

Hi Len,

If you're 100 percent full and have a coffee in your hand, may I suggest some 
advice from Bobby... and words I live by.

Don't warry. Be Happy.

Cheers, Russ
Sweet 35 mk-1



At 07:28 PM 06/02/2017, you wrote:

I think the CBA would work well so far from the little reading I have done. I 
have four 6 volt deep cycle batteries for my house bank and a Link monitor. I 
also have a simple analogue load tester. The problem is the solar panel masks 
any shortfall in the bank by fully charging usually before I make coffee in the 
morning. The house bank isn't quite as full on a rainy day and everything works 
but I would like to know how well. I probably should just leave it alone but if 
the bank is 100% charged but at 50% amp hour capacity I want to know. Len
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Re: Stus-List Battery test

[Russ & Melody via CnC-List]

Hi Len,

If you're 100 percent full and have a coffee in your hand, may I 
suggest some advice from Bobby... and words I live by.


Don't warry. Be Happy.

Cheers, Russ
Sweet 35 mk-1



At 07:28 PM 06/02/2017, you wrote:
I think the CBA would work well so far from the little reading I 
have done. I have four 6 volt deep cycle batteries for my house bank 
and a Link monitor. I also have a simple analogue load tester. The 
problem is the solar panel masks any shortfall in the bank by fully 
charging usually before I make coffee in the morning. The house bank 
isn't quite as full on a rainy day and everything works but I would 
like to know how well. I probably should just leave it alone but if 
the bank is 100% charged but at 50% amp hour capacity I want to know. Len


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Re: Stus-List Battery test

[Dave via CnC-List]

Check also victron BMV 700.  I seem to recall reading that the xantrex unit is 
a buy for resale victron.It was the perfect fit for what I wanted and also 
in the 2" hole that once housed my analog voltmeter.  
Photos here:

http://cncwindstar.blogspot.ca/p/blog-page.html?m=1

Dave.  (Launch booked April 10!  Whitby, on.)

Sent from my iPhone

> On Feb 6, 2017, at 6:50 PM, Rick Brass  wrote:
> 
> After spending some time on a friend's cruising boat that had a Xantrex
> LinkPro battery monitor, I bought a LinkLite for Imzadi.
> 
> Several on EBay for around $200 - and I see the price has gone up a lot
> since I bought mine.
> http://www.ebay.com/itm/Xantrex-Linklite-Battery-Monitor-/311605137761?hash=
> item488d1d1161:g:jmgAAOSwhRxXKO5R=mtr
> 
> The device monitors voltage for two banks, and shows instantaneous current
> in or out for the main bank, total AH used since the last charge for the
> main bank, and % or total AH remaining. It adjusts for the total AH
> available when you do a periodic "synchronize" after a full charge. It
> doesn't show you the total AH capacity for the main bank, but knowing the AH
> used and the & of total remaining you can do some arithmetic to calculate
> the total AH available.
> 
> As a matter of fact, I happen to have done that when I was on the boat on
> Sunday. The house bank was at 93.2% of capacity, and based on the AH used I
> figured my house bank is down to a bit over 400AH from the 460 it was when
> the batteries were installed in 2010.
> 
> Rick Brass
> Washington, NC
> 
> 
> 
> 
> -Original Message-
> From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of
> Mitchell's via CnC-List
> Sent: Monday, February 06, 2017 2:24 PM
> To: CNC List 
> Cc: Mitchell's 
> Subject: Stus-List Battery test
> 
> Here is one for you electrical guys, my batteries are over 5 years old. I
> have all LED lights, a 240 watt solar panel and modern refrigeration. The
> batteries are working fine but there is no way they are still performing as
> new. I would like to monitor their amp hour capacity as they age. Is there a
> simple way to do it or do I need to take them into a battery shop? 
> 90 days to launch! 
> Len Mitchell
> 1989 37+
> Crazy Legs
> Midland On. 
> 
> 
> Sent from my mobile device. 
> 
> ___
> 
> This list is supported by the generous donations of our members. If you wish
> to make a contribution to offset our costs, please go to:
> https://www.paypal.me/stumurray
> 
> All Contributions are greatly appreciated!
> 
> 
> 
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Re: Stus-List Battery test

[Rick Brass via CnC-List]

After spending some time on a friend's cruising boat that had a Xantrex
LinkPro battery monitor, I bought a LinkLite for Imzadi.

Several on EBay for around $200 - and I see the price has gone up a lot
since I bought mine.
http://www.ebay.com/itm/Xantrex-Linklite-Battery-Monitor-/311605137761?hash=
item488d1d1161:g:jmgAAOSwhRxXKO5R=mtr

The device monitors voltage for two banks, and shows instantaneous current
in or out for the main bank, total AH used since the last charge for the
main bank, and % or total AH remaining. It adjusts for the total AH
available when you do a periodic "synchronize" after a full charge. It
doesn't show you the total AH capacity for the main bank, but knowing the AH
used and the & of total remaining you can do some arithmetic to calculate
the total AH available.

As a matter of fact, I happen to have done that when I was on the boat on
Sunday. The house bank was at 93.2% of capacity, and based on the AH used I
figured my house bank is down to a bit over 400AH from the 460 it was when
the batteries were installed in 2010.

Rick Brass
Washington, NC




-Original Message-
From: CnC-List [mailto:cnc-list-boun...@cnc-list.com] On Behalf Of
Mitchell's via CnC-List
Sent: Monday, February 06, 2017 2:24 PM
To: CNC List 
Cc: Mitchell's 
Subject: Stus-List Battery test

Here is one for you electrical guys, my batteries are over 5 years old. I
have all LED lights, a 240 watt solar panel and modern refrigeration. The
batteries are working fine but there is no way they are still performing as
new. I would like to monitor their amp hour capacity as they age. Is there a
simple way to do it or do I need to take them into a battery shop? 
90 days to launch! 
Len Mitchell
1989 37+
Crazy Legs
Midland On. 


Sent from my mobile device. 

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make a contribution to offset our costs, please go to:  
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Re: Stus-List Battery test

[Frederick G Street via CnC-List]

Len — short of using a load tester that discharges the batteries, the most 
reliable way of testing the capacity of batteries is using something like a 
conductance load tester:

https://www.amazon.com/gp/product/B00IZFNJ6Y/ref=as_li_tl?ie=UTF8=1789=390957=B00IZFNJ6Y=as2=carbattcharce-20
 


Yours to have to pay a few hundred dollars for a decent one; but the prices 
have gone down and the quality has gone up at the lower end.

— Fred

Fred Street -- Minneapolis
S/V Oceanis (1979 C Landfall 38) -- on the hard in Bayfield, WI   :^(

> On Feb 6, 2017, at 1:23 PM, Mitchell's via CnC-List  
> wrote:
> 
> Here is one for you electrical guys, my batteries are over 5 years old. I 
> have all LED lights, a 240 watt solar panel and modern refrigeration. The 
> batteries are working fine but there is no way they are still performing as 
> new. I would like to monitor their amp hour capacity as they age. Is there a 
> simple way to do it or do I need to take them into a battery shop? 
> 90 days to launch! 
> Len Mitchell
> 1989 37+
> Crazy Legs
> Midland On.
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make a contribution to offset our costs, please go to:  
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Re: Stus-List Battery test

[Josh Muckley via CnC-List]

Len,

You can get an A-H meter for the boat which is a better gauge of available
charge than using a the typical voltage meter.  With this you can get a
feel of health and performance by using the batteries as normal and
tracking their accumulated A-H  to voltage.  You'd probably want to keep an
ongoing graph to identify future outliers.  It's not perfectly accurate.
As an addition or alternative you can get a load tester.  It will have to
be something that provides a regulated test current, usually capacity
divided by 20 (C/20). A 100Ah battery would need tested at 5amps.
Typically you only go to 50% discharge (11.6v), so an auto shutoff is
prescribed for the most scientificly accurate tests.  Be advised that under
these conditions the test on each battery will take ~10 hours.

Check out the Computer Battery Analyizer.  I have one and I'm impressed.
Very informative and powerful tool.

http://www.westmountainradio.com/product_info.php?products_id=cba4

Josh Muckley
S/V Sea Hawk
1989 C 37+
Solomons, MD


On Feb 6, 2017 2:24 PM, "Mitchell's via CnC-List" 
wrote:

Here is one for you electrical guys, my batteries are over 5 years old. I
have all LED lights, a 240 watt solar panel and modern refrigeration. The
batteries are working fine but there is no way they are still performing as
new. I would like to monitor their amp hour capacity as they age. Is there
a simple way to do it or do I need to take them into a battery shop?
90 days to launch!
Len Mitchell
1989 37+
Crazy Legs
Midland On.


Sent from my mobile device.

___

This list is supported by the generous donations of our members. If you
wish to make a contribution to offset our costs, please go to:
https://www.paypal.me/stumurray

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___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!

Re: Stus-List Battery test

[Bruce Whitmore via CnC-List]

Interesting twist on this issue - and something for everyone to consider.  Our 
new (to us) 1994 37/40+ had batteries from last year in the main bank that were 
showing 12.2 volts just coming off the charger.  The damage was done, but we 
didn't know why.  So, when we put in the batteries this weekend, I immediately 
tested them using the boat's voltage meter.
Hmmm.. Still low ish, variable, and the lights were dim.  

I immediately thought of a bad ground, thanks to an old friend on another 
board.  Not only was there a bad ground, but when I pulled on the negative 
cables as they went through the bilge and by the engine, they crunched.  
Really.  A crunchy feeling like corn flakes in a cable.  Turns out they were 
thoroughly corroded and barely carrying current.  

I verified this by disconnecting the ground wire and, using an extra piece of 
wire as an extension, checked the continuity.  Definitely not a good flow of 
current. It was a real pain to run new cables, but it made a world of 
difference.  

Check those battery cables, and check your ground connection at the engine! 
Bruce Whitmore

(847) 404-5092 (mobile)
bwhitm...@sbcglobal.net


  From: Mitchell's via CnC-List 
 To: CNC List  
Cc: Mitchell's 
 Sent: Monday, February 6, 2017 2:23 PM
 Subject: Stus-List Battery test
   
Here is one for you electrical guys, my batteries are over 5 years old. I have 
all LED lights, a 240 watt solar panel and modern refrigeration. The batteries 
are working fine but there is no way they are still performing as new. I would 
like to monitor their amp hour capacity as they age. Is there a simple way to 
do it or do I need to take them into a battery shop? 
90 days to launch! 
Len Mitchell
1989 37+
Crazy Legs
Midland On. 


Sent from my mobile device. 

___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!


   ___

This list is supported by the generous donations of our members. If you wish to 
make a contribution to offset our costs, please go to:  
https://www.paypal.me/stumurray

All Contributions are greatly appreciated!