Clueless in (not Seattle) Amps, etc.
 

Since refrigeration is probably your largest consumer of power, and most
people don't *really* know how many hours a day their system runs, I would
suggest that you get a 12V run-hour meter and wire it into your system.
Log how many hours it runs and keep that in a spreadsheet and calculate how
much power you're using on a daily basis.

I do this and it lets me know how well the system is working and points out
any potential problems which may be forming. Since I designed and built my
system, I also have a tendancy to play with the expansion valve settings
and thermostat set-points. This allows me see how the changes have
effected the performance. I tend to go a bit overboard and keep track of
both the refrigeration and freezer run hours.

-- Geoff

Clueless in (not Seattle) Amps, etc.
 

On Jul 27, 6:40 am, Skip Gundlach wrote:

Perhaps I'll just have to learn to live on less than 200AH/day,


OH MY GOD !


Skip, you need either:

1) **** can everything: solar, wind, humongous dueling alts and get
one good gen set.

OR

2) walk the streets. find some peyote buttons or lsd and go on a
vision quest. A significant paradigm shift is in order.


Bob

Amps, etc.
 

Wayne.B wrote in
:

On Fri, 27 Jul 2007 05:21:01 -0500, Geoff Schultz
wrote:

And don't forget cooling. A 200A alternator is going to generate a lot
of heat and will need to be cooled. You just can't throw it into an
enclosed engine space and expect it to crank out 200A without burning
up. You need to have a 3 stage controller with a thermocouple on the
alternator and you need to pipe air into the engine space.

Good points. In the end you may find that a generator coupled to an
inverter/charger has a lot to recommend it.


Maybe this is what we need......(c;
http://www.fleetsource.com/Alternator_p/4900j.htm

Will a 4 cyl 4-154 Perkins turn it and the prop simultaneously, or will we
have to wait for the batteries to come up before coming out of neutral on
the tranny??

Larry
--
While in Mexico, I didn't have to press 1 for Spanish.
While in Iran, I didn't have to press 1 for Farsi, either.
While in Florida, I had to press 2 for English.
It just isn't fair.

Amps, etc.
 

On Fri, 27 Jul 2007 07:55:55 -0400, Wayne.B
wrote:

On Thu, 26 Jul 2007 12:55:16 -0500, "KLC Lewis"
wrote:

I don't find anything on
the Smartguage site that says how their meter can do it without a shunt, and
with only two wires connected directly to the battery bank.

It can't of course, it can only guesstimate. If you want to measure
something you need the proper tools. The tool in this case is a
shunt.
That is analagous to using a flowmeter in your fuel line to drive your
speedometer (via a lookup table) ;-)
A shunt is used to measure current as you well know.
The Magic box that looks at the shunt counts in and out then
"guesstimates" based upon a number of parameters set by the installer
that may be right or may be wrong at that point in the banks life. The
final result is therefore ????? However most with amp counters assume
the numbers are gospel!

On the other hand you can argue that all that is really needed is a
digital voltmeter to approximate state of charge. If your batteries
are reading 12.6 volts under a light to moderate load, they are at
100%. Dropping down to 11.6 volts under the same conditions, they are
at 50% and need to be recharged immediately.

Granted (maybe) but the "average" boater has no idea what load is on
at the time, and the average boater feels everything is OK if he sees
12.00 volts!

How do you explain the real life discrepancy between units as
discussed in my original post? The amp counter was WRONG!
Oh and by the way try leaving an amp counter on a battery with no load
for 6 months and see if it reads the correct information! No amps out,
no amps in, bank is 100% !!! is it hell!

--
Richard

Nb "Pound Eater" Parkend G+S
"Governments are like Nappies, they should be changed often."
(For the same reason)

Clueless in (not Seattle) Amps, etc.
 

Skip Gundlach wrote:

I'm obviously missing a great deal of intelligence here.

I had thought we'd properly sized our bank and input sources to allow
for our anticipated usages.

Obviously I was mistaken; I need a large-frame alternator and the
appropriate drive components, in order to only bring my bank to 90%.

Wet cell batteries are a very mature technology.

The rules for them are very simple.

1) If you want to consume 200AH/day, you must generate 250AH/day of
replacement energy.

You can play all kind of regulator games, but in the end, the overall
average replacement rate is about 15% of the bank capacity or in this
case, 15%(750)=112.5A.

The minimum recharge time will be: 250/112.5=2.2 hours.

How you choose to get it done is your business, but the above rules
define the task.

Solar:

For an engineering estimate, use a 2ftx4ft,80W panel which translates
into 10W/sq ft.

Derate 50% for dirt, clouds, angle of attack, etc, thus 5W/sq ft.

As a year around average use 12 hours/day, thus 12hours(5W/sq ft))=60
watt-hours/sq ft/day.

60watt-hours/12volts=5amp-hours/sq ft/day.

To generate 250AH of solar you need 250/5=50sq ft or at least 7
2ftx4ft panels.

Probably not going to happen unless you build a hard bimini so you
have a place to plant your solar garden.

That's why alternators like the L/N 4800/4805 family exist.

Modest size, only 145/165 output depending on model, but either
deliver in excess of 100A at 2,000 alternator.

Ya pays ya money, ya takes ya pick.

Lew

Amps, etc.
 

"Electricky Dicky" wrote in message
...
A shunt is used to measure current as you well know.
The Magic box that looks at the shunt counts in and out then
"guesstimates" based upon a number of parameters set by the installer
that may be right or may be wrong at that point in the banks life. The
final result is therefore ????? However most with amp counters assume
the numbers are gospel!

snippage

--
Richard

Nb "Pound Eater" Parkend G+S
"Governments are like Nappies, they should be changed often."
(For the same reason)

So it really comes down to choosing your choice of "magic boxes" which
"guesstimate"? How is the Smartguage better than the Link 10, if they both
"guesstimate" the state of charge?

Amps, etc.
 

On Thu, 26 Jul 2007 10:23:19 -0700, Pete C
wrote:

On Jul 26, 4:29 pm, Stephen Trapani wrote:
Can't a person extrapolate state of charge with a simple voltmeter?

Good point, you can, with a few caveats which are covered by the
battery FAQ I posted a link to.

I'd probably use the voltmeter as a rough and ready guide on a day to
day basis, and a hydro now and then to verify it.

Cross referring the two could be pretty useful.

This is a wireless SG sensor setup.
Data can be fed to a PDA, laptop or desktop and crunched
by the relevant software for analysis.
http://www.electrosense.com.au/SG-Electrode.htm
Toss out those old hydrometers.
You can probably get a nice setup of these for less than $10k.
Agitator beds for the batteries could be added if desired, but
I haven't looked for them. If I ordered any of this stuff I would
want a couple pocket protectors thrown in gratis.

--Vic

Amps, etc.
 

On Jul 27, 10:06 pm, Vic Smith
wrote:
This is a wireless SG sensor setup.
Data can be fed to a PDA, laptop or desktop and crunched
by the relevant software for analysis.http://www.electrosense.com.au/SG-Electrode.htm
Toss out those old hydrometers.
You can probably get a nice setup of these for less than $10k.
Agitator beds for the batteries could be added if desired, but
I haven't looked for them. If I ordered any of this stuff I would
want a couple pocket protectors thrown in gratis.

LOL!

For checking SG under way a refractometer might be easier, on the
pocket at least! eg:

http://cgi.ebay.com/Battery-Acid-Ant...lycol-Coolant-
Refractometer-
F_W0QQitemZ230154976520QQihZ013QQcategoryZ111537QQ ssPageNameZWDVWQQrdZ1QQcmdZViewItem

cheers,
Pete.

Amps, etc.
 

On Fri, 27 Jul 2007 14:25:53 -0700, Pete C
wrote:

On Jul 27, 10:06 pm, Vic Smith
wrote:
This is a wireless SG sensor setup.
Data can be fed to a PDA, laptop or desktop and crunched
by the relevant software for analysis.http://www.electrosense.com.au/SG-Electrode.htm
Toss out those old hydrometers.
You can probably get a nice setup of these for less than $10k.
Agitator beds for the batteries could be added if desired, but
I haven't looked for them. If I ordered any of this stuff I would
want a couple pocket protectors thrown in gratis.

LOL!

For checking SG under way a refractometer might be easier, on the
pocket at least! eg:

http://cgi.ebay.com/Battery-Acid-Ant...lycol-Coolant-
Refractometer-
F_W0QQitemZ230154976520QQihZ013QQcategoryZ111537Q QssPageNameZWDVWQQrdZ1QQcmdZViewItem

So many gadgets, so little time.

--Vic

Amps, etc.
 

On Fri, 27 Jul 2007 15:07:44 -0500, "KLC Lewis"
wrote:


"Electricky Dicky" wrote in message
.. .
A shunt is used to measure current as you well know.
The Magic box that looks at the shunt counts in and out then
"guesstimates" based upon a number of parameters set by the installer
that may be right or may be wrong at that point in the banks life. The
final result is therefore ????? However most with amp counters assume
the numbers are gospel!

snippage

--
Richard

Nb "Pound Eater" Parkend G+S
"Governments are like Nappies, they should be changed often."
(For the same reason)

So it really comes down to choosing your choice of "magic boxes" which
"guesstimate"? How is the Smartguage better than the Link 10, if they both
"guesstimate" the state of charge?

Don't ask me, it was Wayne that said that the "Smartgauge" estimated
not me!

--
Richard

Nb "Pound Eater" Parkend G+S
"Governments are like Nappies, they should be changed often."
(For the same reason)

Amps, etc.
 

"Electricky Dicky" wrote in message
...
On Fri, 27 Jul 2007 15:07:44 -0500, "KLC Lewis"
wrote:


So it really comes down to choosing your choice of "magic boxes" which
"guesstimate"? How is the Smartguage better than the Link 10, if they both
"guesstimate" the state of charge?

Don't ask me, it was Wayne that said that the "Smartgauge" estimated
not me!

--
Richard

Nb "Pound Eater" Parkend G+S
"Governments are like Nappies, they should be changed often."
(For the same reason)

Sorry, I was thinking you were the one selling the Smartguages. Unless you
are, in which case I still ask the question. They are all magic boxes that
guesstimate, so how does the Smartguage guesstimate better? And if you
aren't the proper one to answer, can the correct person please jump in?

Clueless in (not Seattle) Amps, etc.
 

On Fri, 27 Jul 2007 19:37:37 GMT, Lew Hodgett
wrote stuff
and I replied:

snip

I agree largely with you Lew, but I reckon that you are being a bit
_generous_ with the solar panels' capabilities.

Solar:

For an engineering estimate, use a 2ftx4ft,80W panel which translates
into 10W/sq ft.

Derate 50% for dirt, clouds, angle of attack, etc, thus 5W/sq ft.

As a year around average use 12 hours/day, thus 12hours(5W/sq ft))=60
watt-hours/sq ft/day.

60watt-hours/12volts=5amp-hours/sq ft/day.

To generate 250AH of solar you need 250/5=50sq ft or at least 7
2ftx4ft panels.

Human bevaviour: Bestiality with a brain

Amps, etc.
 

On Fri, 27 Jul 2007 19:20:54 +0000, Larry wrote:

Maybe this is what we need......(c;
http://www.fleetsource.com/Alternator_p/4900j.htm

Will a 4 cyl 4-154 Perkins turn it and the prop simultaneously, or will we
have to wait for the batteries to come up before coming out of neutral on
the tranny??

It will use 3 to 4 hp under load. That should not be a problem if the
Perkins is running OK and you use dual belts.

That's the right unit assuming you can get a mount fabricated and the
Perkins has dual drive sheaves. Nothing less is going to get that
bank of L-16s charged in a reasonable length of time.

Amps, etc.
 

In article om,
Pete C wrote:

LOL!

For checking SG under way a refractometer might be easier, on the
pocket at least! eg:

and the clothes......

Bruce in alaska
--
add a 2 before @

Amps, etc.
 

In article ,
Wayne.B wrote:

On Fri, 27 Jul 2007 19:20:54 +0000, Larry wrote:

Maybe this is what we need......(c;
http://www.fleetsource.com/Alternator_p/4900j.htm

Will a 4 cyl 4-154 Perkins turn it and the prop simultaneously, or will we
have to wait for the batteries to come up before coming out of neutral on
the tranny??

It will use 3 to 4 hp under load. That should not be a problem if the
Perkins is running OK and you use dual belts.

That's the right unit assuming you can get a mount fabricated and the
Perkins has dual drive sheaves. Nothing less is going to get that
bank of L-16s charged in a reasonable length of time.

Actually a single GearTooth Belt and GearTooth Sheaves can transfer
up to 8 HP with ease.....

Bruce in alaska
--
add a 2 before @

Amps, etc.
 

On Sat, 28 Jul 2007 20:02:33 GMT, Bruce in Alaska
wrote:

Actually a single GearTooth Belt and GearTooth Sheaves can transfer
up to 8 HP with ease.....

Probably so but most of us do not have gear tooth sheaves.

Amps, etc.
 

Bruce in Alaska wrote:
In article ,
Wayne.B wrote:


On Fri, 27 Jul 2007 19:20:54 +0000, Larry wrote:


Maybe this is what we need......(c;
http://www.fleetsource.com/Alternator_p/4900j.htm

Will a 4 cyl 4-154 Perkins turn it and the prop simultaneously, or will we
have to wait for the batteries to come up before coming out of neutral on
the tranny??

It will use 3 to 4 hp under load. That should not be a problem if the
Perkins is running OK and you use dual belts.

That's the right unit assuming you can get a mount fabricated and the
Perkins has dual drive sheaves. Nothing less is going to get that
bank of L-16s charged in a reasonable length of time.


Actually a single GearTooth Belt and GearTooth Sheaves can transfer
up to 8 HP with ease.....

Bruce in alaska

You can do 24 HP with an 8 rib micro vee.

But if you have vee belts, it doesn't matter....

--
“TANSTAAFL”

__________________________________________________ __________________________

"A prudent man foresees the difficulties ahead and prepares for them;
The simpleton goes blindly on and suffers the consequences." - Proverbs 22:3
__________________________________________________ __________________________

Amps, etc.
 

Wayne.B wrote in
:

reasonable length of time

= 5 hours from 40% down....(c;

Larry

Amps, etc.
 

Electricky Dicky wrote in
:

snippage


http://www.factorydirect2you.com/di.html
I always thought it would be great to modify a cell cap to permanently
mount the probe for one of these digital hydrometers into one cell on the
house batteries. No guesstimating here....you can READ the GRAVITY, the
only way to tell the condition of charge in a wetcell battery.

Price has come down a lot....$50!

Even if you couldn't mount it, its use would be much easier than a glass
hydrometer with the batteries buried like they are in most yachts. Lots of
boats, you can't even get the glass hydrometer into the cells, much less
actually read it.

Larry
--
While in Mexico, I didn't have to press 1 for Spanish.
While in Iran, I didn't have to press 1 for Farsi, either.
While in Florida, I had to press 2 for English.
It just isn't fair.

Amps, etc.
 

Electricky Dicky wrote in
:

snippage


Yahoo found lots of digital hydrometers....some with probes you can
mount...

http://shopping.yahoo.com/search/;
_ylc=X3oDMTJuYWNqZDEzBF9TAzk2MDc5MjYwBGFkZ3JwAzI4N zA1NjUyMwRldnQDODc3NzE1Mw
RrA2RpZ2l0YWwgaHlkcm9tZXRlcgRvbW0DYnJvYWQEc2VjA2ti BHNsawN0aXRsZQ--?
view=l&p=digital+hydrometer&sp=pall&no_truncation= 1&sem=google

http://tinyurl.com/2kq62e
same URL...much easier to click.

Larry
--
While in Mexico, I didn't have to press 1 for Spanish.
While in Iran, I didn't have to press 1 for Farsi, either.
While in Florida, I had to press 2 for English.
It just isn't fair.

Amps, etc.
 

On Sat, 28 Jul 2007 22:37:14 +0000, Larry wrote:

reasonable length of time

= 5 hours from 40% down....(c;

Larry

That's too long for practical usage. Let's run the numbers:

Trojan L16s are approximately 400 AH, 2 in parallel, 800 AH.

Max recharge rate in bulk charge mode at 25% = 200 amps, 150 if you're
conservative and temperature limited.

AH to be replaced at 40% down up to 80% of full charge = 160 AH (going
above 80% takes too long so must of us settle for that or slightly
higher)

Time to achieve 80% is approx 1 hour, 90% about 2 hours, and that's
good enough. My batteries have been lasting 3+ years with that kind
of usage and I'm OK with it given the amount of time I spend onboard,
and the amount of geneator time the inverter saves me.

Amps, etc.
 

Wayne.B wrote in
:

On Sat, 28 Jul 2007 22:37:14 +0000, Larry wrote:

reasonable length of time

= 5 hours from 40% down....(c;

Larry

That's too long for practical usage. Let's run the numbers:

Trojan L16s are approximately 400 AH, 2 in parallel, 800 AH.

Max recharge rate in bulk charge mode at 25% = 200 amps, 150 if you're
conservative and temperature limited.

AH to be replaced at 40% down up to 80% of full charge = 160 AH (going
above 80% takes too long so must of us settle for that or slightly
higher)

Time to achieve 80% is approx 1 hour, 90% about 2 hours, and that's
good enough. My batteries have been lasting 3+ years with that kind
of usage and I'm OK with it given the amount of time I spend onboard,
and the amount of geneator time the inverter saves me.


That'll work.....It's fine.....

I just don't want to be aboard any boat with 120A applied to these
batteries, sealed away in a really tight box where there is ZERO cooling,
effectively, for hours on end. I'd hate to be the one they blame when
the plates warp and touch each other, resulting in an acid steam
explosion.

Have you ever seen one? Even the stainless flatware sealed away in a
drawer far away from the batteries was just eaten alive...pitted by acid
fumes. All the clothes in the cabinets way up in the V-berth were acid
eaten, too! Everything aboard had to be tossed...anything fuming
sulfuric acid gas could eat. I certainly wouldn't want to be stranded
aboard in some hermit's cove on the hook when it happened! BOOM! The
one I saw was caused by a big battery charger at the dock whos electronic
controller malfunctioned leaving the 40A beast on full current way past
time to shut down, which it couldn't do. I wondered how high the voltage
got at 40A when she blew!

Larry
--

Amps, etc.
 

On Sun, 29 Jul 2007 03:56:48 +0000, Larry wrote:

I just don't want to be aboard any boat with 120A applied to these
batteries, sealed away in a really tight box where there is ZERO cooling,
effectively, for hours on end.

That can not happen with a proper 3 stage charge regulator. It
certainly is not going to happen on a sailboat using the aux engine to
recharge batteries. No one wants to run that engine longer than
necessary.

Clueless in (not Seattle) Amps, etc.-Update
 

Lew Hodgett wrote:
Skip Gundlach wrote:

I'm obviously missing a great deal of intelligence here.

I had thought we'd properly sized our bank and input sources to allow
for our anticipated usages.

Obviously I was mistaken; I need a large-frame alternator and the
appropriate drive components, in order to only bring my bank to 90%.

Wet cell batteries are a very mature technology.

The rules for them are very simple.

1) If you want to consume 200AH/day, you must generate 250AH/day of
replacement energy.

You can play all kind of regulator games, but in the end, the overall
average replacement rate is about 15% of the bank capacity or in this
case, 15%(750)=112.5A.

The minimum recharge time will be: 250/112.5=2.2 hours.

The only way to reduce the recharge time is to increase the size of
the battery bank which in turn allows for a higher recharge rate.

Still no free lunch, but does reduce the recharge time.

Batteries to a cruising sailor are like clamps to a wood worker, you
can never have too many.

How you choose to get it done is your business, but the above rules
define the task.

Solar:

For an engineering estimate, use a 2ftx4ft,80W panel which translates
into 10W/sq ft.

Derate 50% for dirt, clouds, angle of attack, etc, thus 5W/sq ft.

As a year around average use 12 hours/day, thus 12hours(5W/sq ft))=60
watt-hours/sq ft/day.

60watt-hours/12volts=5amp-hours/sq ft/day.

To generate 250AH of solar you need 250/5=50sq ft or at least 7 2ftx4ft
panels.

Probably not going to happen unless you build a hard bimini so you have
a place to plant your solar garden.

That's why alternators like the L/N 4800/4805 family exist.

Modest size, only 145/165 output depending on model, but either deliver
in excess of 100A at 2,000 alternator.

Ya pays ya money, ya takes ya pick.

Lew

Clueless in (not Seattle) Amps, etc.
 

OldNick wrote:

I agree largely with you Lew, but I reckon that you are being a bit
_generous_ with the solar panels' capabilities.

That is why it was called an "engineering estimate"

If you vary more than a few degrees from the equator, you will need
more panels for sure.

Lew

Clueless in (not Seattle) Amps, etc.-Update
 

On Jul 31, 12:38 am, Lew Hodgett wrote:

Batteries to a cruising sailor are like clamps to a wood worker, you
can never have too many.

How about 2 alts and 2 banks, use the banks alternately so one is bulk
charged while the other is absorption charged at the same time. Plenty
of redundancy too.

Maybe 2x 75A alts and controllers are cheaper than a 150A alt and
controller.

Also solar will work better with a bank that is between 50-85% state
of charge.

cheers,
Pete.

Clueless in (not Seattle) Amps, etc.-Update
 

On Thu, 02 Aug 2007 04:29:11 -0700, Pete C
wrote:

Maybe 2x 75A alts and controllers are cheaper than a 150A alt and
controller.

The battery bank in question is close to 800 AH and can not be
recharged from 40 or 50% depletion in a reasonable length of time by a
75 amp alternator. The main cost of the 200 amp alternator is in the
installation work, also an issue with a dual alternator set up.