To: Krogen Discussion List
From: AKAMA
Subject: KK: Feature Article: Krogen Electrical Systems
Date: Thu, 01 Mar 2001 17:28:38 -0800
_________________________________________________________________________
Early members of this list will recall that Louise-Ann and I intend to
recruit qualified people to write informative articles for us. We promised
one on AC/DC electrical systems on Krogens. At long last, here it is!
Frankly, it's been ready for a week or two, but so many new members were
coming on board each day that we decided to hold off a bit.
Arild has agreed to moderate any discussion, so I (Maurice) will do
something most uncharacteristic; I'll keep quiet and let Arild take centre
stage. He admits that he is not a Krogen expert, although he once surveyed
one. But, I spent hours picking his brain and can confirm that he truly
knows about marine electrical systems from stem to stern; and better still,
he's an avid boater.
Here's the article:
Optimising the Krogen Electrical System--by Arild Jensen
Foreword--by Maurice Nunas
I have been corresponding with Arild and following his posts on other email
lists for some time. Louise-Ann and I met him at the 2000 Vallejo Trawler
Fest, where he was a speaker and representative of Xantex, the company that
makes most of the popular inverters used on North American yachts (e.g.,
Heart, Statpower). We chatted for hours and it seemed to me that he has a
great deal of good information to offer Krogen owners. So, I asked Arild to
write this article about Krogen electrical systems for our Krogen Owners'
List.
It seems to me that so much depends on the nature of the boat, both in terms
of size and fitment. Arild agreed and pointed out that sometimes it is
impossible to clearly answer some questions due to the huge number of
variation in electrical system design and installation. Arild drafted the
original article, which I reviewed; I also sent to him related emails
stemming from a notice that I posted on the Krogen Owners' List. This final
version of the article is the result.
Since I know so little about Manatees, I gave him only the dope on the 42
and the 48; so that's the focus of this article. Perhaps Manatee owners can
help to educate us by providing comments! This article is intended to get
a discussion going on our Krogen owners' List. As always, let's keep it
Krogen and leave general matters and pontificating to the other lists.
Typical Installation
There is no such thing as a stock installation on Kadey Krogen boats. Not
only are there differences by model, but also there are differences among
the boats of the same model. The following is assumed in this article to be
the most common arrangement.
-- Single main engine with automotive type alternator (integral regulator)
connected to a dedicated group 27 (KK42) or 8D (KK48) start battery
-- Get home engine (KK48) with automotive type alternator (integral
regulator) connected to the main engine start battery
-- 6 to 12 kW (KK42) or 12 to 20 kW (KK48) generator set with automotive
type alternator (integral regulator) connected to a dedicated group 27 start
battery
-- Two (KK42) or four (KK48) 8D house batteries in two banks with a
1-Both-2-OFF switch
-- Heart 2500 EMS (older boats) or Freedom (newer boats) inverter Split AC
main panel with AC on one side and the remaining loads on the other (KK 48),
light loads (refrigeration, lights and sockets) connected through the
inverter (all)
-- Single DC panel (KK42) or split DC panel, one for ships systems and one
for house systems (KK48)
-- Bow thruster & anchor winch fed from bank two of the house battery
-- Household type refrigerator/freezer
-- Microwave oven
Wish List
-- Silent running (ex. A/C) for at least a weekend
-- Highest, reasonable capacity of batteries
-- Longevity of batteries and components
-- Best charging of all batteries
-- Best inverter set-up
Recommendations
-- Balmar 175 - 200 amp alternator with temp compensated 3-step regulator
-- Prosine 2.0 or 3.0 inverter/charger
-- Truecharge 10 amp two bank charger - optional
-- Link-10 battery monitor - optional
-- Emergency Start battery jumping solenoids - optional
Description
"What's the best set-up for my boat?" is perhaps the #1 FAQ that I hear at
any boat show. Unfortunately, the person asking the question doesn't tell
me what boat they own or what their expectations are. When I was asked this
question as it applies to Kadey Krogen boats, my first reaction was to reply
that there is no single solution that suits all people and every boat.
However, most KK owners have similar usage patterns and the boats are almost
identical as far as factory installed equipment goes. That makes the
criteria easier to specify.
First of all you want reliability, a measure of redundancy and then some
convenience. The reliability comes from using top-notch equipment and
operating it well within its rated performance curve. Buying the least
expensive model is not a good idea if longevity is desired. Convenience has
a price. All sorts of automatic features can be added, provided you can
afford it and are willing to accept a more complex system that may require
additional maintenance. The recommended equipment list will provide you
with a reliable trouble free installation with a minimum of complexity.
Cruising means you want independence from shore power. Therefore you need
the ability to recharge your batteries from the engine while underway but
also from a generator set. However you don't want to listen to a genset all
the time so charging times should be kept to a minimum.
Details
The house bank (4 8Ds) has more than 800 amp hours of capacity. Depending on
age and brand of battery this could be as high as 880 or as low as 780 A-H.
The maximum charge rate is 20% of that A-H total or about 156 - 176 amps.
Therefore you will need a high output alternator which can put out at least
150 amps, and perhaps as much as 175 for optimum charging. In addition you
will need a 3-step regulator with temperature compensation. Not only for the
battery but also for the alternator. The original factory supplied
automotive alternator which keeps your starting battery topped up should be
retained. The new high output alternator is in addition to, not instead of.
Start batteries have a different duty cycle and require separate charging
characteristics. I realize it costs more to add a second alternator, but
now you have some redundancy in charging capability. Companies like Balmar
can offer complete kits of parts to fit nearly all, popular engine
installations.
While on the subject of alternators, the pulley size is critical to optimum
performance. The size selected should produce full rated output when you
are running at your normal cruising speed. If you normally run at 1800 RPM
then select pulley sizes that will give you full alternator output at that
speed. High output alternators are designed to give full output at lower RPM
but they still need to turn about 4000 RPM for full rated output. So now
you are looking at a ratio of 3:1; but if you intend to use the main engine
for charging while at anchor, you may need to look at 4:1 pulley ratios.
Now you would only need an engine speed of 1000 RPM to get full output. If
you get an alternator which gives maximum output at a lower speed so much
the better. Much will depend on what the top speed of your engine. If the
engine is governed for a max of 2400 RPM the 4:1 ratio will give a full
rotor RPM of 9600 RPM which is below the 10,000 max for most alternators.
If this is too much then back off on the ratio but be aware that you now
must have a faster idling speed for a full output charge when at anchor.
Gasoline engines typically only have a 2:1 ratio pulley size.
Alternators get hot at full load. When they get hot, they de-rate and put
out less current. In addition heat kills, eventually causing the windings
to cook and break down. Having a temperature sensor on the alternator
allows the regulator to cut back on the current to reduce the temperature of
the alternator to a safe level. Lead acid batteries tend to deteriorate
above 160¼ F. Therefore a battery temperature sensor must also be used,
since a battery heats up when being charged at high current levels.
House Bank Charger
To charge the batteries from shore power or a genset you need a pretty hefty
charger, such as you find in combination with many inverters. While a Heart
Freedom is the most common inverter charger found on most KK boats, this is
not optimum for several reasons. First of all, the charger is not power
factor corrected. Second, it is a line frequency switched device. What this
means for you is less charging current if the quality of power is less than
perfect. That happens quite often with either shore power and especially
with gensets.
If you are using the genset to drive the charger this could mean quite a bit
longer run time to get the same amount of charge as compared to a power
factor corrected charger such as the Prosine type inverter/charger.
While the Heart Freedom 2500 inverter will run most of the loads onboard,
the modified sine wave output does hammer your inductive load appliances
such as refrigerators and microwave ovens. The net result is a shortened
lifetime compared to running these appliances on a proper sine wave. The
replacement cost of a refrigerator is far more than the cost differential
between the Statpower Prosine inverter and the Heart MSW inverter.
Except for purely resistive loads like toasters, all appliances work better
on pure sine waves. In fact any appliance containing a computer clock chip
has to have a clean sine wave in order to keep correct time. Sophisticated
devices like bread makers, and microwave ovens with digital clocks must have
sine wave power in order to work properly.
Newer Krogens have Heart inverters capable of echo charging. Some people
may object to replacing the Heart unit with a Prosine since only the Heart
has an echo charger. They consider the multi-bank charging capability
essential. This is part of the myth that has built up over the past few
decades. Multi-bank charging was a concept that began before WW-II, when
battery management consisted of a selector switch that allowed you to
completely drain one battery before switching over to the other. Now you
knew you only had half of the power left. Not very sophisticated! It also
wasn't very healthy for the battery. Which is why so many batteries gave up
the ghost after a single season. That wasn't so bad when the house bank
only cost $50 or $100 but today's large house banks often represent hundreds
of dollars investments. A properly cared for battery can easily last five
or six years and some of them last as much as ten years.
While both the Heart and Prosine inverters have similar chargers, there is a
difference in the algorithms used. In addition, the Heart charger is
derived from a line frequency device while the Prosine is a high frequency
switch mode design. The output of a Heart charger has some ripple content,
which causes internal battery heating, and electrical noise in your power
circuits. This latter may be a major annoyance factor if you use 12-volt
stereo equipment. The Prosine charger has power factor correction, which
means less charging time compared to the Heart model of the same rated
current output. Actual comparison tests have demonstrated the superiority
of the Statpower charging algorithm, which translates into longer battery
life.
Multi-Bank Charging
The main difficulty with multi-bank charging stems from the fact only a
single regulator and current source is used to charge multiple batteries
with very different charging requirements. The echo charger used with
Heart inverter/chargers is a voltage follower and will reflect the charging
voltage going to the most depleted battery. This is usually the house bank.
The echo charge limits the maximum charge current to 15 amps so you don't
boil the battery dry immediately. However, if the main battery keeps the
charger in bulk mode and absorption mode long enough then the start battery
is still held at a voltage above the gassing point for too long. Eventually
this will cause electrolyte loss. A starting battery never sees any load
except the starter motor. So why would it require recharging every time your
house battery needs charging?
There is an additional issue with multi-bank charging. Unless all the
batteries are approximately the same age, you will end up with one or more
bad cells or whole batteries in the group. This will begin to hog the
charging current, to the detriment of the other batteries. If it absorbs too
much charging current it will even affect the charge controller and cause
over charging of the other batteries.
If your start batteries sit unused for many months at a time, there is a
case for having a trickle charger provide a maintenance charge from time to
time. In that case, use a separate small charger such as the True Charger
TC10, which is still a sophisticated 3-step charger with automatic 21-day
wake up and check feature. The cost of such a charger is about the same as
the echo charger by itself.
The original 1-Both-2-OFF selector switch should be left in the BOTH
position under normal conditions. The sophisticated circuitry in the
Prosine will shut down the inverter before any damage to the battery occurs
from deep discharge. An alarm will go off reminding you that the battery
voltage has dropped below this threshold. This serves as a reminder to start
the genset for recharging. However, there is still enough power left for
most of your other DC appliances. You cannot use the inverter until the
battery has been recharged.
The reason for combining all the batteries into one single bank has to do
with a physical characteristic of batteries under heavy load. Batteries last
longer if you do not discharge them deeply. By having them all combined
into one bank, you automatically halve the effect of any power consumption.
In addition, when you place a big peak load such as the inverter under full
power, the battery voltage will not collapse as much. The net result is
longer battery life and better system performance. Since the starting
battery is not used for anything else, there should never be a question of
providing complex switching systems in case the starter won't work. For
those people who need the peace of mind of some sort of backup, a simple
solenoid and some wiring from the house battery to the start battery is
sufficient. Pressing a momentary push button closes the contact allowing
the starter to draw power from the house bank and start the engine. This
circuit would normally be in the open circuit condition.
There is no need for combiners, diode isolators or complex battery switching
etc. All batteries have dual charging sources, one engine driven one from
shore power. If you consider the genset separately from shore power, then
you have three sources. The addition of a start solenoid provides emergency
backup in the unlikely event the start battery goes flat.
Battery Monitoring
For those people who like to know what is going on and who like to micro
manage their environment, the addition of a battery monitoring system like
the Link 10 (also sold as E-Meter) greatly enhances the system.
The Prosine 3.0 comes with voltage and current measuring displays but does
not include historical data. The Link 10 has the capability to measure how
much power is added by charging or subtracted by consumption. A calculation
can now be made as to how much charge remains in the battery before it is
empty and needs recharging. The Prosine 2.0 incorporates these features
into the smart display/control panel. However, some people need more than
2000 watts in their inverter, and thus need the Prosine 3.0 inverter model.
Equipment Placement
Heat is the enemy of most equipment. For best performance, it would be best
to locate the inverter outside the hot engine compartment. Failing that, try
and locate it so that it is close to where cooler outside air comes into the
engine room. While long battery cables are not good, you can compensate by
going to a larger cable size. There is no compensation for higher
temperature except to lower it. Blowing hot air doesn't help.
DC GENERATORS
If the boat is only wired with DC appliances and some AC devices that can
run on the inverter full time, you may want to consider the use of what is
often called a DC generator. This is a little motor that only drives a big
DC output alternator for charging the batteries directly. Such a charging
scheme is much more fuel-efficient than running a genset which in turn
drives a charger. A good 100 amp marine charger costs well over a thousand
dollars while an equivalent alternator costs less than half as much. A
10 - 15 HP diesel running near full load to charge a battery is
more efficient than a 25 - 45 HP genset engine running lightly loaded to
drive a charger. A 200-amp alternator will fill the same battery bank two
to three times as fast as most chargers. The majority of consumer chargers
only come in 60 amps or smaller sizes. A 100-amp Mastervolt charger cost
US$2195.00
End
So, there you have it! We are sure that some of you will have some
questions, some of you will have suggestions to make, and still others will
have opinions as to what they think the ideal set-up is for a Krogen
electrical system. Let the questions and discussion begin! But, please
remember our motto on this list, "keep it civil, keep it legal and keep it
Krogen". Think of this bit of cyberspace as our private and exclusive
ladies and gentleman's club. Pour me a Cognac and light my stogie Jeeves,
while I sink into this leather chair and re-read this article...
Best to all,
Maurice & Louise-Ann Nunas
M/V AKAMA
Pier 2, Ponggol Marina
Singapore
-----------------------------------------------------------------------------
To: Krogen Discussion List
From: Tony Marshall
Subject: KK: Krogen Electrical Systems
Date: Fri, 02 Mar 2001 07:59:16 -0800
Am I correct in thinking that Arild is suggesting removing the Heart MSW
inverter, which apparently is a popular owner option at fitting-out
time, and replacing it with the ProSine sinewave inverter? This seems
expensive advice, which he cost-justifies by protecting the
refrigerator. Unless I am mistaken, it is more common to find a Norcold
refrigerator in newer Krogens such as "Growler". Older boats may have
replaced original refrigeration with domestic units because they are so
much cheaper. I believe that the Norcold system runs on DC, which it
gets by converting 110 vac if present, or from ship's DC otherwise. Is
the Norcold converter an inductive load which would not like the MSW
output of the Heart? Unless I am wrong, what happens inside the Norcold
is very similar to what happens when we power laptops and other small
battery-powered electronics from the mains through a converter, and the
Statpower MSW unit seems to be compatible with these devices. What am I
missing?
My Heart 3kva inverter is powered by a dedicated bank of batteries
(separate from the house bank), charged whenever shorepower or gen power
is present. I don't expect the microwave clock to run correctly (it
runs at double speed under inverter power), and I don't use a laser
printer, so I have difficulty in seeing the economics of swapping out
the Heart for the ProSine, unless there is a good market for used
Hearts.
Allerton D. Marshall
33 Old Fort Drive
Hilton Head Island, SC 29926
-----------------------------------------------------------------------------
To: Krogen Discussion List
From: Arild Jensen
Subject: RE: KK: Krogen Electrical Systems
Date: Fri, 02 Mar 2001 14:53:17 -0800
-----Original Message-----
From: Tony Marshall [mailto:tonymarshall@hargray.com]
Subject: KK: Krogen Electrical Systems
Allerton Marshall asked:
Am I correct in thinking that Arild is suggesting removing the Heart MSW
inverter, which apparently is a popular owner option at fitting-out
time, and replacing it with the ProSine sinewave inverter?
Arild replies:
No!! I was not suggesting that you replace a working unit.
If you are considering a replacement or upgrade then give some thought to
the Prosine alternative.
If you have just dicovered that a number of expensive motor driven
appliances have to be serviced or replaced because the motors are shot;
then its time to evaluate the merits of pure sine versus modified
sinewave.
If you are looking at replacing a dual voltage Norcold fridge which
admittedly is very expensive, then take a look at the cost of a regular
apartment fridge, powered by an inverter, possibly a sinewave model.
regards
Arild
-----------------------------------------------------------------------------
To: Krogen Discussion List
From: Bryant Vann
Subject: Re: KK: Feature Article: Krogen Electrical Systems
Date: Fri, 02 Mar 2001 08:52:04 -0800
Arild, et al,
>Optimising the Krogen Electrical System--by Arild Jensen
Great article. Thanks for taking the time to put this together.
>It seems to me that so much depends on the nature of the boat, both in terms
>of size and fitment.
I also think your cruising "style" can affect what you choose. There's
little point in outfitting a boat to spend weeks at anchor when you only
"cruise" marina-to-marina -- never getting the hook wet. I also think it's
inportant to consider your "starting place." All 42s and many 48s are now
bought as "previously loved" boats. This means you usually have the
"benefit" of what previous owners have installed. We came from a VERY
simple sailboat, so most of what things electrical came with our Salty Lady
was a complete mystery at the beginning. Much of what little we understood
seemed "all wrong." However, due to my state of near total ignorance, I
promised myself to leave the system alone until I figured out how the boat
had been operated by her previous owners. After trying to figure it out on
my own, I finally started running down the first owners -- the folks who
had set the boat up originally and cruised her extensively. Liveaboards
sometimes have a way of "disappearing" so this effort took months.
However, in the end it was WELL worth it. What had seemed a big mess
turned out to be VERY clever -- not only in how the system was set up, but
it how it was operated (a whole 'nuther subject for discussion). After six
years of ownership now, we have changed very little -- mostly just in the
way of upgrading things when they broke.
One more thing... Some folks run the genset a LOT -- for things other than
battery charging. Some folks like really hot water for showers -- some run
the AC most of the day during the heat of summer -- some run the AC for
heat in the spring and fall -- some need to run it for watermaking, cooking
(if the stove is AC) It seems to me that the FIRST thing one needs to do
is to figure out what your operations are going to be and THEN size the
batteries, alternator, charger, inverter, genset, etc. to those needs.
That's what our boat's first owners did, and they did an EXCELLENT job of
matching the daily run-time requirements of all the systems on board.
Again, once they told us how they did it (operated the boat), it made all
the sense in the world.
>Typical Installation
>There is no such thing as a stock installation on Kadey Krogen boats. Not
>only are there differences by model, but also there are differences among
>the boats of the same model.
I couldn't agree more...
>-- Single main engine with automotive type alternator (integral regulator)
>connected to a dedicated group 27 (KK42) or 8D (KK48) start battery
The KK42 (of 1986 vintage) was originally set up with only two 8Ds in the
engine room. A 1-Both-2-OFF switch in the engine room selected which was
the starting battery -- and ALSO determined which battery was charged when
the engine was running. A SECOND 1-Both-2-OFF switch on the DC panel
selected which battery fed the "house." Since the switches are wired in
parallel, the BOTH functions were identical, though the wiring to the
"house" switch is much longer.
>-- 6 to 12 kW (KK42) or 12 to 20 kW (KK48) generator set with automotive
>type alternator (integral regulator) connected to a dedicated group 27 start
>battery
That's the way our boat is set up, but since the gensets typically were not
installed by the factory, others may differ.
>-- Two (KK42) or four (KK48) 8D house batteries in two banks with a
>1-Both-2-OFF switch
I suspect there are very few KK42s still in this original configuration.
For example, our 2 8Ds were long ago replaced by 6 golf cart batteries --
putting 660 AH in the SAME box where the 440 AH were. Fortunately the
battery boxes in the 1986 boats were tall enough already to hold the golf
cart batteries. Of course, the other big reason for going with the golf
cart batteries is cost -- the same AH at 12 volts as an 8D for 80 to $90
vs. $$$$$. In addition, it is a LOT easier to move a golf cart battery
than an 8D since they weigh about half as much.
>-- Heart 2500 EMS (older boats) or Freedom (newer boats) inverter Split AC
>main panel with AC on one side and the remaining loads on the other (KK 48),
>light loads (refrigeration, lights and sockets) connected through the
>inverter (all)
The 1986-vintage boats probably had no inverter at all when they came from
the factory. Ours has an old-model Trace ( a MSW unit) which the first
owners installed. Also, the AC panel is NOT split as you suggest. The
A/Cs were usually not installed by the factory, and the two 30-amp "legs"
already had house circuits on both when the dealer started the AC
installation. Also, each of our two A/Cs is a 16000 BTU unit, which
together draw about 35 amps (including the seawater pump), according to my
notes. Unfortunately, this is too much for a 30-amp shorepower circuit.
One of the drawbacks to our configuration is that it is REAL easy to
accidentally switch on the hot-water heater and draw the house battery down
REAL fast when the inverter is suppllying the 110 VAC!
>-- Bow thruster & anchor winch fed from bank two of the house battery
I suspect, like us, folks have found that having a dedicated 8D or two next
to the bow thruster is a better arrangement. Again one or both were
dealer-installed in the '86 42s, so configurations vary.
>-- Household type refrigerator/freezer
Our boat had a holding plate system installed. I've seen a number of boats
set up this way. On OUR boat, this is the driver for operations at anchor.
It runs off 110 VAC and needs to be run 2 to 3 hours a day. Since it
draws about 8 to 10 amps, it needs to have an engine running (genset or
main engine w. high-output alternator and inverter) to operate it. This
running requirement provides plenty of time to recharge the house
batteries, so we're able to "live" with 12-volt consumption of about 100 AH
a day -- a good match for the 660 AH capacity we have on board. There's a
second battery box already on board (must have been part of the original
equipment) so we could easily double this capacity, but we'd rather use it
for "spare parts!"
>-- Microwave oven
Indispensable for us, but, again, it didn't come from the Krogen factory.
>Recommendations
>-- Balmar 175 - 200 amp alternator with temp compensated 3-step regulator
Balmar isn't the only possibility, of course -- and may not be the best
choice either. I seriously question the use of their regulators. I took
one look at the one (ARS-3) that came with MY Balmar alternator, read the
instructions about "tweeking" the tiny potentiometer, and tossed it in the
trash. I've never been sorry I installed one from Hehr instead.
>-- Prosine 2.0 or 3.0 inverter/charger
I guess I'm willing to be convinced that "pure" sine waves are needed --
unless you want to use AC dimmers. All my motors have been running fine
for 15 years on the old Trace.
>-- Truecharge 10 amp two bank charger - optional
Seems like a good idea. If the inverter "goes south" you can easily live
without it for a time -- but living without the 110-VAC charger function
would be most annoying. Our Trace doesn't have a charger function so we
have a separate 110 VAC charger (which isn't redundant).
>-- Link-10 battery monitor - optional
We use a 4-digit DVM in conjuction with the Nigel Calder voltage vs.
charge-level curve. It works amazingly well -- even without allowing a
resting period before measuring battery voltage.
>-- Emergency Start battery jumping solenoids - optional
Or maybe just using the second 1-Both-2-OFF switch in the engine room -- or
jumper cables if you have to reach the genset battery.
>All sorts of automatic features can be added, provided you can
>afford it and are willing to accept a more complex system that may require
>additional maintenance. The recommended equipment list will provide you
>with a reliable trouble free installation with a minimum of complexity.
I've seen a LOT of complexity on some Krogens (and other boats as well).
Any failure ANYWHERE often is a "cruise-ender" and means a trip to the
"experts" to get the system going again. I've even seen a 42 with a genset
that starts itself when the batteries get too low!
>Cruising means you want independence from shore power. Therefore you need
>the ability to recharge your batteries from the engine while underway but
>also from a generator set. However you don't want to listen to a genset all
>the time so charging times should be kept to a minimum.
If all you need to do is charge batteries, why not run the main engine
instead? They're usually much less annoying to your neighbors.
>The house bank (4 8Ds) has more than 800 amp hours of capacity. Depending on
>age and brand of battery this could be as high as 880 or as low as 780 A-H.
>The maximum charge rate is 20% of that A-H total or about 156 - 176 amps.
>Therefore you will need a high output alternator which can put out at least
>150 amps, and perhaps as much as 175 for optimum charging. In addition you
>will need a 3-step regulator with temperature compensation. Not only for the
>battery but also for the alternator. The original factory supplied
>automotive alternator which keeps your starting battery topped up should be
>retained
Others have led us to question this. We have been told that trying to
drive an alternator this large is going to require TWO belts. The FL came
with a double pulley and used one of them to drive the original alternator.
Sounds like leaving the original alternator in place would require THREE
pulleys on the engine. Maybe the Cat in the 48s already has this
arrangement... Otherwise, a lower output second alternator and ONE belt
might be a better choice.
>While on the subject of alternators, the pulley size is critical to optimum
>performance
Excellent point.
>House Bank Charger
At one point we used a Statpower 110 VAC multi-bank charger for the various
banks on board. This was MOST unsatisfactory. I THINK the problem was
that I had one of the outputs attached to the genset battery (stupid, now
that I think about it). Whenever the Genset was running and genset
alternator and 110 VAC charger were BOTH trying to charge the same battery.
Whatever it was, the Statpower didn't like it and blew up twice before I
caught on!
>Sophisticated
>devices like bread makers, and microwave ovens with digital clocks must have
>sine wave power in order to work properly.
I would think the correct inverter FREQUENCY would be what a clock needs,
not necessarily pure sine waves. Our microwave, breadmaker, etc. work just
fine off the old Trace with MSW -- and the laptop and printer do just fine
as well.
>Newer Krogens have Heart inverters capable of echo charging.
Could you elaborate on what this is?
>A starting battery never sees any load
>except the starter motor. So why would it require recharging every time your
>house battery needs charging?
So why would you even connect it to a charger? Whenever you start the
engine, it gets recharged by the alternator, so why not keep it separate
from the 110 VAC charger?
>The original 1-Both-2-OFF selector switch should be left in the BOTH
>position under normal conditions.
I guess you're assuming this switching isn't actually putting the start
battery in parallel with the house battery -- this WAS how the factory
setup worked on the 42s, thus leaving the switch in the BOTH position would
be risky for some boats (easy to run the start battery down with DC loads).
>For those people who like to know what is going on and who like to micro
>manage their environment, the addition of a battery monitoring system like
>the Link 10 (also sold as E-Meter) greatly enhances the system.
I have seen a LOT of people spend a LOT of time fretting about the errors
in these types of capacity monitors. Maybe the newer ones have better
algorithms. In the meantime, I'll stick with my DVM. When the voltage
gest down to 12.40 VDC, 25% (more or less) of the capacity has been used,
and it's time to turn off the TV and go to bed!
>Equipment Placement
[snip]
>Blowing hot air doesn't help.
EXCELLENT point!
-----------------------------------------------------------------------------
To: Krogen Discussion List
From: AKAMA
Subject: RE: KK: Krogen Electrical Systems
Date: Sat, 03 Mar 2001 01:18:09 -0800
I promised to be quiet, but just have to jump in on this one. I have the
EMS-2800 (a 240-Volt 50-Hertz unit) and its MSW will not run my electric
lights properly (they have touch pads for on/off and for dimming. BTW,
interestingly, they will not run on the generator set! They run fine on
shore power.
Also, because we live aboard, we've got a lot of electrical stuff. The
Heart nearly burnt the boat down one day because I had a Bosh battery
charger for my electric drill plugged into it. For some reason, the Bosh
hates the Heart, overheated, overcharged the battery and when I came along
and discovered it, things were smelling VERY hot. I shudder to think what
would have happened had I gone for a beer before retuning (I might have been
crying in my beer). Yes, all of this is due to my inattentiveness, but I
suspect that a sine wave inverter would have not had this problem.
I will not replace a perfectly good MSW inverter (but I will be more
careful). However, the Heart has been rebuilt once already (previous owner
bathed it in salt water when demonstrating to me how to change the speed
log). If it goes south again (knock on wood that it does not) we will
replace with sine wave power.
My 2 cents worth.
Maurice
Maurice & Louise-Ann Nunas
M/V AKAMA
Pier 2, Ponggol Marina
Singapore
-----Original Message-----
From: Tony Marshall [mailto:tonymarshall@hargray.com]
Sent: March 2, 2001 11:59 PM
To: Krogen Discussion List
Subject: KK: Krogen Electrical Systems
Am I correct in thinking that Arild is suggesting removing the Heart MSW
inverter, which apparently is a popular owner option at fitting-out
time, and replacing it with the ProSine sinewave inverter? This seems
expensive advice, which he cost-justifies by protecting the
refrigerator
-----------------------------------------------------------------------------
From: Arild Jensen
To: "'vann@his.com'"
Subject: RE: KK: Feature Article: Krogen Electrical Systems
Date: Mon, 5 Mar 2001 14:11:27 -0800
Arild replies:
You comment on a lot of points. I will try to deal with them in sequence.
-----Original Message-----
From: Bryant Vann [mailto:vann@his.com]
To: Krogen Discussion List
Subject: Re: KK: Feature Article: Krogen Electrical Systems
> I also think your cruising "style" can affect what you choose.
Agreed. However that is a subject for a whole separate article.
You were fortunate to get a boat fitted out by a knowledgeable and
competent cruising couple.
I have seen just as many boats mangled by well intentioned but
inexperienced owners.
>One more thing... Some folks run the genset a LOT -- for things other than
>battery charging.
Yes, and that is why people should consider other options such as DC
generators and mechanical driven cold plate compressors, water makers etc.
Certainly, driving a lot of the loads off the main engine is fine as long
as the engine is loaded sufficiently. Also, some engines are better than
others for light load running without fouling up. I don't know exactly
what factors come into play.
>The 1986-vintage boats probably had no inverter at all when they came from
>the factory. Ours has an old-model Trace ( a MSW unit) which the first
>owners installed. Also, the AC panel is NOT split as you suggest. The
>A/Cs were usually not installed by the factory, and the two 30-amp "legs"
>already had house circuits on both when the dealer started the AC
>installation.
In effect this amounts to a kind of split panel. I agree that with two A/C
units each 16,000 BTU this poses a problem for power management.
>Recommendations
>-- Balmar 175 - 200 amp alternator with temp compensated 3-step regulator
Balmar isn't the only possibility, of course -- and may not be the best
choice either. I seriously question the use of their regulators. I took
one look at the one (ARS-3) that came with MY Balmar alternator, read the
instructions about "tweeking" the tiny potentiometer, and tossed it in the
trash. I've never been sorry I installed one from Hehr instead.
The ARS -3 is not their current production model. That is a couple of
generations back.
>Others have led us to question this. We have been told that trying to
>drive an alternator this large is going to require TWO belts. The FL came
>with a double pulley and used one of them to drive the original alternator.
>Sounds like leaving the original alternator in place would require THREE
>pulleys on the engine. Maybe the Cat in the 48s already has this
>arrangement... Otherwise, a lower output second alternator and ONE belt
>might be a better choice.
What is really important is the contact area at each pulley. With a
traditional Vee belt you can only get something like 1/3 of the pulley
circumference in contact with a belt. In order to get enough surface area
in contact you either got a bigger ( wider ) belt or more belts.
The new serpentine belts are so thin that they can wrap around the pulley
much further and thus increase the contact area.
I would like to point out that on many car engines there are situations
where three items are driven by the same belt.
On one car I had both the water pump and alternator were driven by one belt
and the power steering pump was driven by another belt.
Quite often the air injection pump and air conditioner are also driven by
one belt.
In the newer engines one single serpentine belt driven all the
acccessories.
>
>House Bank Charger
>At one point we used a Statpower 110 VAC multi-bank charger for the various
>banks on board. This was MOST unsatisfactory. I THINK the problem was
>that I had one of the outputs attached to the genset battery (stupid, now
>alternator and 110 VAC charger were BOTH trying to charge the same battery.
>Whatever it was, the Statpower didn't like it and blew up twice before I
>caught on!
>that I think about it). Whenever the Genset was running and genset
Multi bank charging is one of the biggest mistakes committed by nearly
everyone.
As near as I can figure out this is a concept dating back to WWII
As long as the batteries are of equal size and composition, and they
receive roughly equal usage; there is no problem with charging from a
single source.
However, as soon as the battery banks are of unequal size or the duty cycle
differs markedly, it doesn't work.
AS you have already figured out mixing a 3 stage charger and a fixed output
taper charger ( alternator ) on the same battery at the same time is
definitely a no no!
Was the Statpower charger a black model or a yellow model?
We discovered a number of gremlins in the black model and have fixed these
plus affed some extra features such s AGM charge algorithms and a fixed
power supply output.
We still recommend that if you insist on connecting the charger to a
genset and then driving the charger from the same genset then you have to
install a disconnect relay in the line to the genset battery. This relay is
activated by the AC output of the genset.
It is my personal opinion, that permanently installing a charger on
starting batteries is a waste.
I have been driving cars for 40 years and the number of times when I have
had to charge my starter battery because it ran flat while the car was
parked
is few and far between. In each case the reason was obvious and
preventable.
Cars have far more parasitic loads on the single start battery than most
boats have.
A properly designed and installed marine system will not have any loads
connected to a starter battery. Therefore it will only ruin flat if there is
a problem starting the engine. That is why we have bypass solonoids or
manual cross over switches for emergency use.
>Sophisticated
>devices like bread makers, and microwave ovens with digital clocks must
have
>sine wave power in order to work properly.
I would think the correct inverter FREQUENCY would be what a clock needs,
not necessarily pure sine waves. Our microwave, breadmaker, etc. work just
fine off the old Trace with MSW -- and the laptop and printer do just fine
as well.
Most clock chips actually trigger on the zero crossing point in the
waveform rather than the peak.
Clock chips that trigger on the peaks are more suceptible to noise spikes
and thus tend to run fast when powered by noisy utility power.
When you drive a zero crossing clock chip with MSW waveforms, the clock
tends to double trigger on the flat dwell time at the zero crossing point.
For this reason, many micro processor controlled appliances may run fast
when powered by MSW type inverters.
There is another issue related to MSW. Such waveforms contain a lot of
harmonics. These harmonics may create interference with sensitive equipment.
Computers normally do not have a problem because they have a switch mode
power supply. This strips off any waveform anomaly, converts it to DC and
then proceeds to filter and cocnvert it to the relevant voltage needed by
the computer.
Laser printers and some color copiers do have a problem with MSW. The
better quality equipment with well designed power supplies do not have a
problem.
The cheap products are usually worse for having interaction problems with
MSW.
>Newer Krogens have Heart inverters capable of echo charging.
Could you elaborate on what this is?
An echo charger is a voltage follower device that limits the current going
to a second battery.
However, since the Echo charger follows the voltage of the main charging
source, then the secondary battery may still get left in the wrong mode
for longer than if it had its own dedicated charger.
The Heart Echo charger limits current to 15 amps. You can buy an external
echo charger for use with any charger, but the new Freedom inverters have
provision for two echo chargers built into the case.
>A starting battery never sees any load
>except the starter motor. So why would it require recharging every time
your
>house battery needs charging?
So why would you even connect it to a charger? Whenever you start the
engine, it gets recharged by the alternator, so why not keep it separate
from the 110 VAC charger?
My point exactly!
Back to this multi-bank myth. Unfortunately, most people still think in
those terms and "demand" a three bank charger.
They percieve a single bank charger as somehow being deficient.
Having a multi-bank charger now becomes a marketing issue. If you do not
have one and the competition does, you lose sales.
The real cynics percieve my suggestion of seperate chargers as merely a
ploy to sell more chargers.
>The original 1-Both-2-OFF selector switch should be left in the BOTH
>position under normal conditions.
I guess you're assuming this switching isn't actually putting the start
battery in parallel with the house battery -- this WAS how the factory
setup worked on the 42s, thus leaving the switch in the BOTH position would
be risky for some boats (easy to run the start battery down with DC loads).
Actually, I was thinking of running the start and house bank in parallel
while the main engine is running. Then as soon as the engine stops, you
manually change the selector switch so that the start battery is isolated
until you need it for starting the next time.
What many people do not know is the fact that these selector switches come
in several varieties. One has aux contacts that break the field circuit of
the alternator before the main contact is opened. This prevents the output
from going sky high under open circuit conditions.
The other type only have the main contacts that break before maing the next
contact. And of course there are also some switches that make befoer
breaking.
This also prevents the alternator output from going open circuit.
It has been my experience that most people do not even know that these
variations exist, thus they do not specify the correct switch for their
particular application.
>I have seen a LOT of people spend a LOT of time fretting about the errors
>in these types of capacity monitors. Maybe the newer ones have better
>algorithms. In the meantime, I'll stick with my DVM. When the voltage
>gest down to 12.40 VDC, 25% (more or less) of the capacity has been used,
>and it's time to turn off the TV and go to bed!
Couldn't agree with you more. However, there are a lot of people who just
have to know. I have had a number of clients who are retired electrical
engineers etc. and they just have to have all the gadgets. Common sense
and manual control goes a long way; provided you know what you are doing.
At the other end of the spectrum is the non technical type. These people
don't know an electron from an election and couldn't care less.
However, they do want all the conveneinces and they want fully automatic
systems that handle everything plus keep them up to date on all the
details.
You have obviously developed a very sucessful conservative style that suits
you perfectly. You made a point of learning how your system works and you
are willing to abide by the constraints imposed by that particular setup.
It may not suit every other boat and owner.
-----------------------------------------------------------------------------
To: Krogen Discussion List
From: Arild Jensen
Subject: Sinewave vs MSW was ( KK: Krogen Electrical Systems)
Date: Mon, 05 Mar 2001 14:38:20 -0800
Arild replies:
At the risk of sounding like a sales pitch; let me point out that many
electronic products are waveform sensitive.
The Bosch charger mentioned by Maurice is but one example.
Our brochures for Portawattz MSW products specifically warn customers about
the new generation of fast chargers for cordless tools, cell phones etc.
We have learned the hard way that these new p designs do not like non
sinewave AC power.
It is simply a sign of changing technology. Twenty odd years ago inverters
used mechanical vibrators to switch DC power so that a transformer could
change it into 120 volts complete with fierce ripple and a wealth of
harmonics.
Knocking the corners off the square waveshape was the first step in the
right direction. It reduced the amount of radiated hash and eddy current
heating in inductive loads like motors. But wave shaping cost money since
it needed betrer control circuits and filters.
Trace engineering produces a near sine wave which only has about 72
switching transitions in the sine wave. Even that can produce problems in
some sensitive equipment.
The sine wave produced by the Statpower prosine has 4000 switching
transitions in a single sine wave at line frequency. The switching
technology is controlled by a crystal oscillator to ensure absolutely stable
60 hertz ( or 50 Hertz ) output and some very complex and sophisticated
filtering circuits are used to produce a nearly perfect sinewave.
When the output from any AC generator ( also called an alternator ) is
distorted by inductive or capacitive loading the powr factor decreases from
a perfect 1.0
This lead or lag cannot be corrected for by a simple transformer. Heart
designs uses a basic line frequency switched circuit involving solid state
switches and basic line frequenccy transformers. Some gensets do not put
out a good sinewave when fully loaded. In fact some gensets have as much as
20% harmonic distortion.
I'm quoting published specs from the manufacturer, not hurling accusations.
Resistive loads like toastersand light bulbs don't care. However touch
controls which uses body capacitance, speed controls which uses SCR's and
timing circuits which uses zero crossing or peak detectors are decidely
unhappy with modified square wave power.
There is some overshoot and ringing in most MSW inverter outputs. This
also causes problems for electronic control circuits.
You normally cannot use a MSW inverter at the same time as you run a SSB
radio. Just ask any ham operator.
Cheers
Arild
-----Original Message-----
From: AKAMA [mailto:Nunas@pacific.net.sg]
Subject: RE: KK: Krogen Electrical Systems
Maurice wrote:
I have the EMS-2800 (a 240-Volt 50-Hertz unit) and its MSW will not run my
electric
lights properly (they have touch pads for on/off and for dimming. BTW,
interestingly, they will not run on the generator set! They run fine on
shore power.
<<< snip>>>
The Heart nearly burnt the boat down one day because I had a Bosh battery
charger for my electric drill plugged into it. For some reason, the Bosh
hates the Heart, overheated, overcharged the battery . . .
My 2 cents worth.
Maurice
-----Original Message-----
From: Tony Marshall [mailto:tonymarshall@hargray.com]
Subject: KK: Krogen Electrical Systems
Am I correct in thinking that Arild is suggesting removing the Heart MSW
inverter, which apparently is a popular owner option at fitting-out
time, and replacing it with the ProSine sinewave inverter?
Tony Marshal