On Sun, 20 Mar 2005 19:38:13 -0500, "John Cassara"
wrote:

The long winded point is that a 900AH Battery and an inverter will not run a
Heater all weekend.

=================================

That's true but it will run a heater for 7 or 8 hours at night which
is all you really need (assuming you can recharge in the morning).

On Sun, 20 Mar 2005 21:23:15 -0500, Larry W4CSC
wrote:

"Skip Gundlach" skipgundlach sez use my name at earthlink dot
fishcatcher (net) - with apologies for the spamtrap wrote in
:

Hm. Help me with the math. As a lapsed math, physics and chem major,
I don't remember my stuff all that well. However, I'll have right in
the neighborhood of 500W solar

How big are these solar panels? A Kyocera KC120 panel at 120 watts is:
Max power: 120 Watts
Max voltage: 16.9 Volts
Max current: 7.10 Amps
Dimensions (LxWxD): 56.1" x 25.7" x 2.2"
Weight: 26.3 lbs

4 of those kinda hinders going on deck, I suppose. Or, do you mean 500
watt-hours per day?? 500 watts x 8 hours = 4 KWh/day...pretty nice!

, and a KISS wind generator in the
Caribbean. Various vendors suggest I take the wattage and divide by 3,
or 4 if really lousy weather, for a reasonable typical AH input,
daily. My math has that at 170-125AH/day, plus some other unknown -
but apparently pretty substantial - AH from a KISS.

Solar is useless on cloudy days, but that's when the wind is usually
blowing so you got it covered.

Speaking of wind power, have you see http://www.otherpower.com/
These homebrewers are really producing KWh!


Our anticipated daily budget is about 125AH; we'll have (for
simplicity in this calculation) ~1250AH capacity. It's our
presumption that we'll have 4-5 days capacity, in the most
unimaginable (in the Caribbean) circumstance of continuous no wind or
sun.

Have I missed something here?

No, not at all. The big inverters are great for QUICK and TEMPORARY loads,
even heavy loads if the battery banks can produce the heavy load currents
without sagging a lot.

Too bad boats don't use 48 volts instead of "car power". The whole thing
becomes much more efficient as the voltage rises.

Design development is under way for 42 volt car systems

Brian W

"Brian Whatcott" wrote in message
...
Design development is under way for 42 volt car systems

It's already there. AFAIK all new VW marine diesels have a 42V system to
power the injectors.

Meindert

"Meindert Sprang" wrote in
:

It's already there. AFAIK all new VW marine diesels have a 42V system to
power the injectors.

Meindert




I think the Toyota Prius hybrid takes this even further with a 480VDC
system, doesn't it? A friend has one and it's quite impressive, once you
get used to NOT starting the engine to take off from the parking lot.
That's a bit unnerving, just turning it on and driving away...(c;

In article ,
Wayne.B wrote:

The distribution panel (or behind it) is usually the only place where
you can find a centralized point where you can interrupt the power.

The inverter has to be wired in such a way that it can never see an
independant source of AC power at its output terminals. As long as
both the AC input to the inverter/charger and the inverter output pass
through seperate circuit breakers, there should be no issue with
wiring codes.

How would you do it?

Bzzzzt, Wrong answer..... would you like to try again, for what is
behind Curtain No. 2 ?

Never EVER have a Input Feed and an Output Feed in the same Panel
and on the same buss. That has got to be the dumbest Idea I have ever
seen, posted to a newsgroup, and "Totaly" against ABS and NEC Electrical
Codes. Yes, it is possible to so such a thing, but to keep people from
doing so, is why there are ABS and NEC codes in the first place.

The correct way to do this is to have an Input Distribution Panel,
and an Inverted Output Distribution Panel, and any interconnection
directly between the two, would need to be thru an InterLocked Transfer
Switch.

Shore Power, Generator, would be interlocked so they are mutually
exclusive inputs to the Input Distribution Panel. That panel then
feeds all noninverted loads thru individual breakers, and the Inverter
input, thru its own individual Breaker. The Output Distribution Panel
would also have it's own individual breaker in the Input Distribution
Panel for Transfer Power Feeds.

Inverter output, Transfer Power Feed, would be interlocked so as to
be mututally exclusive inputs to the Inverted Output Distribution
Panel. All inverted power circuits would then be individually
breakered from this panel.

This keeps the Genset and Shorepower mutally exclusivly seperate
from each other so as no combination of breaker settings could
ever connect them together.

This also keeps the Inverter Input and Output mutually exclusivly
seperate from each other so that no combination of breaker settings
could ever connect them together.

Any other system, that does not provbide the above Mutual Exclusivity
will certainly, and eventually, let out the MAGIC SMOKE, that makes the
electrons run thru the wires. Either you, the mate, or just a friend
aboard, will make a breaker setting mistake, and out will come the
MAGIC SMOKE, and the results will be BAD.....


Me

Wayne.B wrote in
:

Have you ever read Pracitcal Sailor? They are an (expensive)


No, I haven't. I think I saw some little, few pages newsletter at Boat/US
for $8. Is that it??

I think they do sell off the newstand now. I'm pretty sure
I saw one at West Marine. They generally run about 16 pages
and boilerplate is maroon in color.

Doug
s/v Callista

"Larry W4CSC" wrote in message
...
Wayne.B wrote in
:

Have you ever read Pracitcal Sailor? They are an (expensive)


No, I haven't. I think I saw some little, few pages newsletter at Boat/US
for $8. Is that it??

"Wayne.B" wrote in message
...
On Sun, 20 Mar 2005 19:38:13 -0500, "John Cassara"
wrote:

The long winded point is that a 900AH Battery and an inverter will not run
a
Heater all weekend.

=================================

That's true but it will run a heater for 7 or 8 hours at night which
is all you really need (assuming you can recharge in the morning).

Nope. Our Pelonus ceramic cube heater draws around 110A. With a
900AH battery bank you would be lucky to get 4 hours. Probably
less since it is drawing much more than the 20 hour rate from which
your 900AH rating is based. We have a 500AH+ bank in our mobile
canvas shop. The heater is good for about an hour.

Doug

"Me" wrote in message
...
In article ,
Wayne.B wrote:

The distribution panel (or behind it) is usually the only place where
you can find a centralized point where you can interrupt the power.

The inverter has to be wired in such a way that it can never see an
independant source of AC power at its output terminals. As long as
both the AC input to the inverter/charger and the inverter output pass
through seperate circuit breakers, there should be no issue with
wiring codes.

How would you do it?

Bzzzzt, Wrong answer..... would you like to try again, for what is
behind Curtain No. 2 ?

Never EVER have a Input Feed and an Output Feed in the same Panel
and on the same buss. That has got to be the dumbest Idea I have ever
seen, posted to a newsgroup, and "Totaly" against ABS and NEC Electrical
Codes. Yes, it is possible to so such a thing, but to keep people from
doing so, is why there are ABS and NEC codes in the first place.

The correct way to do this is to have an Input Distribution Panel,
and an Inverted Output Distribution Panel, and any interconnection
directly between the two, would need to be thru an InterLocked Transfer
Switch.

Shore Power, Generator, would be interlocked so they are mutually
exclusive inputs to the Input Distribution Panel. That panel then
feeds all noninverted loads thru individual breakers, and the Inverter
input, thru its own individual Breaker. The Output Distribution Panel
would also have it's own individual breaker in the Input Distribution
Panel for Transfer Power Feeds.

Inverter output, Transfer Power Feed, would be interlocked so as to
be mututally exclusive inputs to the Inverted Output Distribution
Panel. All inverted power circuits would then be individually
breakered from this panel.

This keeps the Genset and Shorepower mutally exclusivly seperate
from each other so as no combination of breaker settings could
ever connect them together.

This also keeps the Inverter Input and Output mutually exclusivly
seperate from each other so that no combination of breaker settings
could ever connect them together.

Any other system, that does not provbide the above Mutual Exclusivity
will certainly, and eventually, let out the MAGIC SMOKE, that makes the
electrons run thru the wires. Either you, the mate, or just a friend
aboard, will make a breaker setting mistake, and out will come the
MAGIC SMOKE, and the results will be BAD.....


Me

All ture, except the part about two separate panels. My main AC panel
has interlocks for shore/genset/inverter plus distribution for 2 30A
circuits.
Off the shelf and ABYC accepted.

Hi Doug

You mean 110 Volts not amps don't you? About 13.5 amps.
JR;


Doug Dotson wrote:
"Wayne.B" wrote in message
...

On Sun, 20 Mar 2005 19:38:13 -0500, "John Cassara"
wrote:


The long winded point is that a 900AH Battery and an inverter will not run
a
Heater all weekend.

=================================

That's true but it will run a heater for 7 or 8 hours at night which
is all you really need (assuming you can recharge in the morning).


Nope. Our Pelonus ceramic cube heater draws around 110A. With a
900AH battery bank you would be lucky to get 4 hours. Probably
less since it is drawing much more than the 20 hour rate from which
your 900AH rating is based. We have a 500AH+ bank in our mobile
canvas shop. The heater is good for about an hour.

Doug