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Paul
 
Posts: n/a
Default New owner - Question about AC power

Hi all, I'll find out this week if I'm a new owner. God help us all.

The boat is a 30' Wellcraft.

We're going to use the boat almost exclusively on weekends with probably 1
or 2 times in the summer where we'll be able to spend a week on it. It will
basically be our cottage. We're not new to cruising, just new to having our
own boat for cruising.

The boat doesn't have a generator and I'm not sure if I need one. Here is
what I'm thinking, hopefully you guys can give me some advice.

What if I set it up with 2 deep cycle batteries, a high output alternator on
one engine and an inverter.

We're not looking to run a small city, just make some coffee and toast in
the morning, possibly run a bit of stove or microwave at lunch or dinner and
maybe watch a movie in the evening. If I'm working then I'll probably want
to either charge my laptop or run it on ships power for a while.

This of course on top of regular DC usage for water, fridge, lights, etc.

It doesn't have air although if we go hardcore into the later fall season
and early spring we'll want to bring a little heater with us.

My thinking is this. It will be hooked up to shore power all week with the 3
stage charger making sure my house bank is topped up. If we run down below
the threshold while were at anchor I can run the engine (I know, it's a very
expensive generator) to get us back up to about 80% charge.

That's assuming we anchor the entire time and not go for a mid-day cruise
which will have the benefit of charging us back up. And also assuming that
we don't go for a visit to somewhere with dockage and shorepower -- which we
would most definitely do for a day or so during the weeklongs, and probably
do during some of the weekends.

It also seems to me like I could configure for this and try it out to see
how it works. If I find I'm running the engine too much I could then buy a
little generator since the rest of the setup as described above would be
required anyway.

Do this sound like a reasonable approach?


  #2   Report Post  
Rural Knight
 
Posts: n/a
Default New owner - Question about AC power


"Paul" wrote in message
le.rogers.com...

~~ snippage ~~

Do this sound like a reasonable approach?


Doable? Yes.

Should you do it this way?

No.

Guaranteed that you will find a way to drain the batteries more
than once.

Spend the money now and get a little 1500 watt Honda generator
or equivalent - I carry one on my offshore center console just to
run the radios and electronics while drifting.

Makes more sense than constantly charging and discharging the
batteries.

Just my opinion.

Later,

Tom


  #3   Report Post  
noah
 
Posts: n/a
Default New owner - Question about AC power

On Thu, 31 Jul 2003 11:49:45 GMT, "Rural Knight"
wrote:


"Paul" wrote in message
ble.rogers.com...

~~ snippage ~~

Do this sound like a reasonable approach?


Doable? Yes.

Should you do it this way?

No.

Guaranteed that you will find a way to drain the batteries more
than once.

Spend the money now and get a little 1500 watt Honda generator
or equivalent - I carry one on my offshore center console just to
run the radios and electronics while drifting.

Makes more sense than constantly charging and discharging the
batteries.

Just my opinion.

Later,

Tom


"...offshore center console.." ???
....crap...I was just starting to like you. )
noah

....saw an awesome CC today on the highway, headed South on I-87 about
at Saratoga in a nasty rain. A "Fountain", maybe 28', with twin
225's. I fell in love, but I had to leave her. (
noah ---- smelled fish all the way to Albany

Courtesy of Lee Yeaton,
See the boats of rec.boats
www.TheBayGuide.com/rec.boats
  #4   Report Post  
Rural Knight
 
Posts: n/a
Default New owner - Question about AC power


"noah" wrote in message
...
On Thu, 31 Jul 2003 11:49:45 GMT, "Rural Knight"
wrote:


"Paul" wrote in message
ble.rogers.com...

~~ snippage ~~

Do this sound like a reasonable approach?


Doable? Yes.

Should you do it this way?

No.

Guaranteed that you will find a way to drain the batteries more
than once.

Spend the money now and get a little 1500 watt Honda generator
or equivalent - I carry one on my offshore center console just to
run the radios and electronics while drifting.

Makes more sense than constantly charging and discharging the
batteries.

Just my opinion.

Later,

Tom


"...offshore center console.." ???
...crap...I was just starting to like you. )
noah

...saw an awesome CC today on the highway, headed South on I-87 about
at Saratoga in a nasty rain. A "Fountain", maybe 28', with twin
225's. I fell in love, but I had to leave her. (
noah ---- smelled fish all the way to Albany


I almost bought a Fountain - came really close. It was
located in Florida though and I didn't feel like running it
up the coast this spring. I would have had to wait to
trailer it, so I scratched that one off the list.

I have a Contender 31 although why they say it's a 31 I don't
know because it's 32 1/2 feet long - I call it a 32. I just
bought it this year in fact. Spring and Fall are my prime time
fishing periods and this boat gets me to where I want to go
in the shortest time possible.

I have twin 225 Merc Optimax - awesome engines and if you don't
push the revs, they are fairly efficient.

For inshore, I have a 200C Ranger center console with a 200
Evinrude FICHT which I also like a lot. That boat is used
primarily inshore and for the larger sweet water lakes around here.

I also have a small aluminum rowboat for smaller ponds for summer
flyfishing with a brandy new Briggs & Stratton 5 hp outboard. Cute
little engine.

And then there is my '74 Christ Craft/Thompson Corsair project
boat. And a Glastron 20 foot project boat which I'm not really
sure what I'm going to do with other than maybe strip the engine
out of it, sell the trailer and junk the hull.

Later,

Tom


  #5   Report Post  
Larry
 
Posts: n/a
Default New owner - Question about AC power

Power from a battery bank is real easy to get these days. Of course,
boat power from a boat parts place costs three times as much for the
same technology.

The problem with DC power is the very limited SOURCE, the storage of
power in batteries. Deep cycle batteries, the kind you can discharge
down without eating holes in the plates like starting batteries will,
are rated in ampere-hours (AH) at some rate that makes the
manufacturer look good, like 10A or 20A...it's on the label, or is
supposed to be. 20A at 13V = 260 watts out power output. The
inverter is going to eat up about 5-10% of that, say 20 watts for fun,
because no inverter is 100% efficient, so you're left at that level
with 240 watts of AC power, a thousand watts short of the coffee maker
which draws 1200 watts for 10 minutes, then, if it's got a pot heater,
50w continuously.

The AH rating on the house batteries DROPS significantly as load
increases on them. The chemistry freeing up electrons and moving the
dissolved salt created when you discharge becomes much less efficient
the more electrons you use.

Let's look at the coffee pot load for a minute. If the coffee pot
uses 1200 watts and the inverter at this load level puts out 90% of
what it gets from the battery to the pot, 1200/.9=1333W from the
battery. Let's pretend the heavily loaded battery and the corroded
cables to the inverter put 12V on the inverter under load (it's
probably LESS at this current level). 1333W/12V= 111 amps of load at
12V. Make SURE the wiring from the inverter to the battery is LARGER
than the wires to the starter! Starters on gas engines draw about 80A
starting the beast. We're over that, just making coffee!

Question - How long can you run the starter before the battery is
dead? 3 minutes of CONTINUOUS cranking? 4? 5? It ain't gonna make
10, is it? At 111 amps, we're gonna need a powerful battery to make
that coffee, aren't we?! See the math working, here? Think the 12V
wires will get warm?..(c; They will. Small ones will melt....

Question - Armed with this information, how much current will a Heart
4000 watt inverter draw that's, say, 95% efficient?

4000W/.95=4210W/12V=THREE HUNDRED FIFTY AMPS! Wow! We're gonna need
some POWERFUL HEAVY WIRES to hook that baby up! #000 is 200A
service!

Now, let's be honest. Most boaters, even the rich ones, are
cheapskates. They're using the golf cart batteries from some discount
house rated at 225AH, 6V with two in series to get 12V. These
batteries are the most bang for the buck. My stepvan has 4 of them
for house batteries on a 500W inverter and they work just fine at an
80A load. They're probably only 160AH at 80A, but that's still 2
hours at FULL LOAD of all my DC and inverter loads...not bad. But,
350A is just gonna make them EXPLODE from internal heat generated way
beyond their capacity. You CAN add more banks, if you got the room,
in parallel. Four banks in parallel would reduce the load on each
battery to under 100A on that beast. See the problem?

1333W for 10 minutes on a carafe coffee maker that doesn't have a
heater IS doable. 111A for 10 minutes = 111x.16667hrs = 18AH.
That'll work on the golf cart batteries derated to 150AH at 111A.
It'll make about 9 pots of coffee, won't it? That works.

You can do the math approximations for your other loads. As you can
see, there really isn't many Watthours of electricity available from
225AH batteries.

I have a saying....."Nothing is funnier than watching a yachtsman with
a new 4KW Heart inverter carrying his electric heater down the dock
with a big smile on his face."......(c; Think about it....

He's gonna need those old WW2 diesel-electric submarine batteries we
used to service at Charleston Naval Shipyard's battery shop. EACH 2V
cell was about 7 ft tall, 4' x 3', weighed about half a ton and had
6,250AH rating at, I think I remember, 400A load. 6 of them will heat
the boat.....er, ah.....if it'll float.

Now, if you want some NEAT power, serious power, go to a Honda dealer
and look at the EU2000i tiny portable gas generator. It weighs about
35 pounds, makes very little noise, is amazingly easy on gas with its
OHV 4-stroke engine and the computer in it varies the engine speed
depending on your load, dropping it down really low at low loads under
800W because you always get 60 Hz filtered good enough for computers
out of it 2KW inverter! I use the EU1000i 1KW model in my service
truck. It'll pull my little 5000 Btu AC! MUCH more efficient, MUCH
less weight and you can load it to 1500 watts 24/7 for about 6 gallons
of gas! Before buying it locally, though, put EU2000i into google.com
and find the best price. Mine came from a sawmill supply company in
Oregon, on the other side of the country from Charleston. I can buy a
LOT of "service" for the $380 I saved....



Larry W4CSC

"No, NO, Mr Spock! I said beam me down a WRENCH,
not a WENCH! KIRK OUT!"



  #6   Report Post  
Peggie Hall
 
Posts: n/a
Default New owner - Question about AC power


You may not need as much ac power as you think...although my boats were
"all electric" and had 6.5 kw gensets, there were times when I didn't
want to listen to the damn thing.

We're not looking to run a small city, just make some coffee and toast in
the morning,


Easily done without power. The toast--and even eggs and bacon--can be
cooked on a marine propane grill--which you'll want anyway. Coffee can
be made over a propane camp stove--either in a percolator, or by
boiling water and using a Melita or a fresh press. Grill and stove
properly mounted to meet safety standards in the cockpit, of course.

possibly run a bit of stove or microwave at lunch or dinner...


Again, use the grill for your meat, corn on the cob, baked potatoes
etc...you can even steam veggies in foil packets on the grill. Salads
and sandwiches for lunch if you don't want to grill burgers and dogs.

A little advance prep at home, and you can eat like kings aboard with
almost no effort and very little cleanup, without electricity.

maybe watch a movie in the evening.


Buy a DC powered TV. Or read a good book instead.

If I'm working then I'll probably want
to either charge my laptop or run it on ships power for a while.


I ran mine off a small inverter for use in cars--about $50 at any
computer retailor or Radio Shack...installed a "cigarette lighter"
receptacle in my dinette for it.

This of course on top of regular DC usage for water, fridge, lights, etc.


The fridge is the biggest battery drain on most boats. The more often
the door is opened, the more the compressor has to run....conversely,
the less often it's opened, the less it runs and the less power it
needs. Conserve battery power by keeping your drinks in a cooler and
reserving the fridge for food (may not be necessary when only the two of
you are aboard, but almost essential if you have kids and/or when you
have guests aboard). Last thing before you turn in for the night--after
you're sure the door won't be opened again, turn it off at the
breaker...it'll stay cold enough even to keep ice cream till morning.
Just don't forget to turn it back on again when you get up!

Just some suggestions that worked for me for nearly 20 years.

Peggie
----------
Peggie Hall
Specializing in marine sanitation since 1987
Author "Get Rid of Boat Odors - A Guide To Marine Sanitation Systems and
Other Sources of Aggravation and Odor"
http://www.seaworthy.com/html/get_ri...oat_odors.html


It doesn't have air although if we go hardcore into the later fall season
and early spring we'll want to bring a little heater with us.

My thinking is this. It will be hooked up to shore power all week with the 3
stage charger making sure my house bank is topped up. If we run down below
the threshold while were at anchor I can run the engine (I know, it's a very
expensive generator) to get us back up to about 80% charge.

That's assuming we anchor the entire time and not go for a mid-day cruise
which will have the benefit of charging us back up. And also assuming that
we don't go for a visit to somewhere with dockage and shorepower -- which we
would most definitely do for a day or so during the weeklongs, and probably
do during some of the weekends.

It also seems to me like I could configure for this and try it out to see
how it works. If I find I'm running the engine too much I could then buy a
little generator since the rest of the setup as described above would be
required anyway.

Do this sound like a reasonable approach?



  #7   Report Post  
Paul
 
Posts: n/a
Default New owner - Question about AC power

Thank you all for your advice and for the time you spent replying, it's much
appreciated.

I laughed when I realized that it never occurred to me to use a small
invertor for the laptop ... when Peggie said it I realized it was the most
obvious thing in the world but it had never occurred to me and probably
wouldn't have for a while. Geez ... I can be thick headed.

Laptop also solves the problem of watching a movie in the evening ... built
in dvd player.

My friend has a 1kw Honda generator that he offered to me and now I'll give
it another think. I also wouldn't mind having it here at home in the winter
in case we lose power (I'm in Ottawa, everyone here remembers the ice
storm).

I've been worried about propane on a boat because of its tendency to settle
low but I'll see how everyone else is rigged and check out the rules on
that, perhaps that deserves a rethink too.

I appreciated the math on the coffee maker but I'm going to run those
numbers myself. It seems to get pretty complex.

I have about a million more questions ... thanks again for your help on this
one.


"Paul" wrote in message
le.rogers.com...
Hi all, I'll find out this week if I'm a new owner. God help us all.

The boat is a 30' Wellcraft.

We're going to use the boat almost exclusively on weekends with probably 1
or 2 times in the summer where we'll be able to spend a week on it. It

will
basically be our cottage. We're not new to cruising, just new to having

our
own boat for cruising.

The boat doesn't have a generator and I'm not sure if I need one. Here is
what I'm thinking, hopefully you guys can give me some advice.

What if I set it up with 2 deep cycle batteries, a high output alternator

on
one engine and an inverter.

We're not looking to run a small city, just make some coffee and toast in
the morning, possibly run a bit of stove or microwave at lunch or dinner

and
maybe watch a movie in the evening. If I'm working then I'll probably want
to either charge my laptop or run it on ships power for a while.

This of course on top of regular DC usage for water, fridge, lights, etc.

It doesn't have air although if we go hardcore into the later fall season
and early spring we'll want to bring a little heater with us.

My thinking is this. It will be hooked up to shore power all week with the

3
stage charger making sure my house bank is topped up. If we run down below
the threshold while were at anchor I can run the engine (I know, it's a

very
expensive generator) to get us back up to about 80% charge.

That's assuming we anchor the entire time and not go for a mid-day cruise
which will have the benefit of charging us back up. And also assuming that
we don't go for a visit to somewhere with dockage and shorepower -- which

we
would most definitely do for a day or so during the weeklongs, and

probably
do during some of the weekends.

It also seems to me like I could configure for this and try it out to see
how it works. If I find I'm running the engine too much I could then buy a
little generator since the rest of the setup as described above would be
required anyway.

Do this sound like a reasonable approach?




  #8   Report Post  
joseph pietruszewski
 
Posts: n/a
Default New owner - Question about AC power

I have the 1000 watt Honda generator the size is great but you have to watch
what you try to run with it. I made a cord that plugs in to my shore power
and I set it on the swim platform I went to Target and checked all of the
coffee pots and found a melita with 2 travel mugs that only draws 800 watts
We also found a electric griddle that works great at 350 degrees.But the
thing we use it the most for is the blender my wife has fallen in love with
my margaritas 1/2 can frozen limeade ice tequila and tripplesec
"Paul" wrote in message
le.rogers.com...
Thank you all for your advice and for the time you spent replying, it's

much
appreciated.

I laughed when I realized that it never occurred to me to use a small
invertor for the laptop ... when Peggie said it I realized it was the most
obvious thing in the world but it had never occurred to me and probably
wouldn't have for a while. Geez ... I can be thick headed.

Laptop also solves the problem of watching a movie in the evening ...

built
in dvd player.

My friend has a 1kw Honda generator that he offered to me and now I'll

give
it another think. I also wouldn't mind having it here at home in the

winter
in case we lose power (I'm in Ottawa, everyone here remembers the ice
storm).

I've been worried about propane on a boat because of its tendency to

settle
low but I'll see how everyone else is rigged and check out the rules on
that, perhaps that deserves a rethink too.

I appreciated the math on the coffee maker but I'm going to run those
numbers myself. It seems to get pretty complex.

I have about a million more questions ... thanks again for your help on

this
one.


"Paul" wrote in message
le.rogers.com...
Hi all, I'll find out this week if I'm a new owner. God help us all.

The boat is a 30' Wellcraft.

We're going to use the boat almost exclusively on weekends with probably

1
or 2 times in the summer where we'll be able to spend a week on it. It

will
basically be our cottage. We're not new to cruising, just new to having

our
own boat for cruising.

The boat doesn't have a generator and I'm not sure if I need one. Here

is
what I'm thinking, hopefully you guys can give me some advice.

What if I set it up with 2 deep cycle batteries, a high output

alternator
on
one engine and an inverter.

We're not looking to run a small city, just make some coffee and toast

in
the morning, possibly run a bit of stove or microwave at lunch or dinner

and
maybe watch a movie in the evening. If I'm working then I'll probably

want
to either charge my laptop or run it on ships power for a while.

This of course on top of regular DC usage for water, fridge, lights,

etc.

It doesn't have air although if we go hardcore into the later fall

season
and early spring we'll want to bring a little heater with us.

My thinking is this. It will be hooked up to shore power all week with

the
3
stage charger making sure my house bank is topped up. If we run down

below
the threshold while were at anchor I can run the engine (I know, it's a

very
expensive generator) to get us back up to about 80% charge.

That's assuming we anchor the entire time and not go for a mid-day

cruise
which will have the benefit of charging us back up. And also assuming

that
we don't go for a visit to somewhere with dockage and shorepower --

which
we
would most definitely do for a day or so during the weeklongs, and

probably
do during some of the weekends.

It also seems to me like I could configure for this and try it out to

see
how it works. If I find I'm running the engine too much I could then buy

a
little generator since the rest of the setup as described above would be
required anyway.

Do this sound like a reasonable approach?






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