I believe that my alternator is over charging. If this is so, I guess
that the regulator is not working right. here's my story. 93 four
winns/omc/ford/king cobra. one new 27 battery beginning of the season
the boat has 2. put in 1750 watt inverter this year. when engine is
running and on battery #2, the invertor reads that it is getting to
much power and shuts off, so I use it without the engine running or
when the switch is set to the other battery. 3 weeks ago the main fuse
(on the engine) popped while I was cruising. the voltage gage on the
dash read that I was chargining way to high until I reset the circuit
breaker. All seemed fine for a few weeks. yesterday, the main breaker
popped twice. I am going to take it to a pro if I can find one who has
the time to look at it. What else should I do or look for. hoping to
learn some as well as get the boat fixed. the boat has 2 gages to read
the batteries. one on the dash and one down below. I know that it
should be tested with external meters, but I do not know what or how,
but want to learn.

thanks

A couple of thoughts: 1) A group 27 battery is MUCH too small for a
1,750 watt inverter. 2) If you are going to troubleshoot and
maintain the system yourself, you need to invest in a good digital
multimeter and take the time to learn some basic electronic skills.
3) At this point there is some risk that you've blown the diodes in
your alternator. I'd recommend getting a experienced mechanic to check
it out.

You don't say what kind of inverter you have, or what
engine/alternator combination. Did you install the inverter yourself?
Is you alternator up to recharging a large battery bank , or do you
have a generator and external charger?
===============================================

On 17 Aug 2003 06:36:11 -0700,
(Richard Malcolm) wrote:
I believe that my alternator is over charging. If this is so, I guess
that the regulator is not working right. here's my story. 93 four
winns/omc/ford/king cobra. one new 27 battery beginning of the season
the boat has 2. put in 1750 watt inverter this year. when engine is
running and on battery #2, the invertor reads that it is getting to
much power and shuts off, so I use it without the engine running or
when the switch is set to the other battery. 3 weeks ago the main fuse
(on the engine) popped while I was cruising. the voltage gage on the
dash read that I was chargining way to high until I reset the circuit
breaker. All seemed fine for a few weeks. yesterday, the main breaker
popped twice. I am going to take it to a pro if I can find one who has
the time to look at it. What else should I do or look for. hoping to
learn some as well as get the boat fixed. the boat has 2 gages to read
the batteries. one on the dash and one down below. I know that it
should be tested with external meters, but I do not know what or how,
but want to learn.

thanks

Does this thing have a battery switch or are the batteries just
connected together in parallel? Battery switches should never be
moved with the engine running. Any alternator not hooked to a battery
puts out huge spikes of pulsating voltage that will destroy everything
in its path.

Just from what you've said, I'm leaning towards a loose battery cable
or a corroded one that puts resistance between the charging alternator
and the battery. The pulsating current of the alternator through
corrosion caused an extra voltage drop to add to the battery's natural
voltage, causing all kinds of trouble if the resistance it's pulsing
through is between the inverter and the battery posts, too. This is
why I always try to hook up electronics breaker panels to SEPARATE
terminals on the battery than the one the charging alternator uses so
these high voltage spike could only happen if the battery opened up,
as safe as I can make it.

High voltage spikes on all of it will occur, also, if the battery has
a dead cell in it, adding a big resistance right inside the battery
itself. You can hear a dead cell or corroded terminals on the boat's
AM/FM radio speaker. It shows up as alternator "whine" whos pitch
follows the RPM of the engine, of course.

Every boater should have a battery test meter. I paid $18 for mine
from Harbor Freight, a hardware discount place full of Chinese tools
made by slave labor. The test meter has an analog voltmeter and a
switched 50 amp load you switch on by holding the spring loaded switch
on. The meter is calibrated for unloaded charging voltages so you can
see what the battery voltage was before starting the engine, charging
voltage after the engine is running. Then, with the engine off, you
can load up the battery with the hot wire load in the box that gets
red hot to watch the battery's voltage discharge curve with the big
50A load for up to a minute to get an indication of its starting
capacity and plate integrity.

If the batteries are not "sealed", as many of the new ones are to
prevent you from just adding distilled water to them, rather than
swapping them out to make the battery store richer, you also need a
compensated hydrometer, which is identified by the thermometer built
into it to measure the electrolyte's temperature you've sucked up into
the glass. Cheap hydrometers are nearly useless as the specific
gravity you are trying to measure to see how the electrolyte is doing
varies WIDELY with temperature. A good hydrometer has a calibrating
chart so you can see what the gravity of the cells are at the
temperature on the thermometer....a correction chart for the float
reading. Of course, on these new gelcells and fancy Optima batteries
you're stuck with whatever happens in there.....at their mercy.

So, my guess until we get more information, is a corroded connection,
probably on the battery, itself, or a dead cell .......or, of course,
a shorted out field regulator.

How about some questions, now?

1 - Can you open the batteries to see what level the electrolyte is?
Batteries that are being overcharged gassify their electrolytes away
and need frequent distilled water injections to keep them from drying
up.

2 - Does the battery get too hot to touch while the engine is at
cruise speed? Overcharging makes them REALLY HOT. Normal charging
makes them warm, but not too hot to touch.

3 - Do you hear a high pitched whining in any electronics with a
speaker, even with the volume control set to zero? If there's
corrosion or a dead cell, the pulsating alternator, even a good one,
will make a whine in the speakers.

4 - Have you opened the battery caps and added distilled water high
enough to cover the lead plates? Manufacturers trying to make like
their batteries are "maintenance free", which is all bull**** to sell
batteries to naive people who don't need them, still have to have
removable tops, usually covering 3 cells at a time, that fit flush
with the battery top to hide them. They need that so the dealers can
open up the cells to add the electrolyte when they receive them from
storage dry. This gives them infinite shelf life stored dry. Pry up
these caps with a screwdriver and look into the cells. Buy gallon
jugs of DISTILLED WATER ONLY, not spring water or city water or hose
water (all of which contain calcium that will eat the electrolyte) and
fill the cells just up to the bottom of the filling cones down inside
the battery. Do NOT fill the cells to the top or you'll have acid all
over. If all the cells are dry and need lots of water....you HAVE the
overcharging problem you think you do. If all the cells but one need
water, the one that doesn't is 99% a DEAD CELL and the others are all
being overcharged by the regulator trying, in vain, to get the battery
to 14V when it only has 6 good cells....and needs immediate
replacement. The load meter will INSTANTLY find a battery with the
dead cell as soon as you put the 50A load on it. It'll drop 2V lower
than "normal" which is about 11.8-12.0V at 50A. (The meters are zoned
good/bad for this test so you don't have to remember that.)

After you initially start caring for them, check them monthly and
watch the electrolyte levels, which should all vary together. If
you're adding a lot of DISTILLED water to the cells month after
month....either the alternator is overcharging or you're leaving some
battery charger on way too long for good health. Modern batteries
hardly use any electrolyte in a year if they're being charged
properly.

Isn't boat maintenance fun?!......(c;



On 17 Aug 2003 06:36:11 -0700,
(Richard Malcolm) wrote:

I believe that my alternator is over charging. If this is so, I guess
that the regulator is not working right. here's my story. 93 four
winns/omc/ford/king cobra. one new 27 battery beginning of the season
the boat has 2. put in 1750 watt inverter this year. when engine is
running and on battery #2, the invertor reads that it is getting to
much power and shuts off, so I use it without the engine running or
when the switch is set to the other battery. 3 weeks ago the main fuse
(on the engine) popped while I was cruising. the voltage gage on the
dash read that I was chargining way to high until I reset the circuit
breaker. All seemed fine for a few weeks. yesterday, the main breaker
popped twice. I am going to take it to a pro if I can find one who has
the time to look at it. What else should I do or look for. hoping to
learn some as well as get the boat fixed. the boat has 2 gages to read
the batteries. one on the dash and one down below. I know that it
should be tested with external meters, but I do not know what or how,
but want to learn.

thanks


Larry W4CSC

Maybe we could get the power grid fixed if every politician
regulating the power companies wasn't on their payrolls.

On Sun, 17 Aug 2003 10:56:57 -0400, Wayne.B
wrote:

A couple of thoughts: 1) A group 27 battery is MUCH too small for a
1,750 watt inverter. 2) If you are going to troubleshoot and
maintain the system yourself, you need to invest in a good digital
multimeter and take the time to learn some basic electronic skills.
3) At this point there is some risk that you've blown the diodes in
your alternator. I'd recommend getting a experienced mechanic to check
it out.

You don't say what kind of inverter you have, or what
engine/alternator combination. Did you install the inverter yourself?
Is you alternator up to recharging a large battery bank , or do you
have a generator and external charger?
===============================================

I also agree with Wayne. 1750 watts at 12V is gonna draw 150-160 amps
off those batteries at full power and will warp the hell out of the
lead plates in the batteries which aren't designed for this CONTINUOUS
loading. Starting batteries are designed to put out this current for
a FEW SECONDS, then require long cooling periods to let the
electrolyte cool the poor plates. One session with a hair dryer
drawing 1250 watts (probably about 110-120A) is enough to destroy
them.

The shorting plates may be what's blowing the battery fuse link.

AS you've already got the oversized inverter noone should be allowed
to produce and sell to consumers, the only safe thing would be to put
a SINGLE 30A fuse in it to prevent the family from overheating the
batteries in the future......or getting some seriously HUGE, HEAVY
batteries that can sink this kind of loading.....

Sorry I didn't address this issue in my first post...thanks Wayne.

Nothing is funnier than seeing a boater with a new 4KW inverter
carrying his electric heater down the dock with a big smile on his
face.....(c;



Larry W4CSC

Maybe we could get the power grid fixed if every politician
regulating the power companies wasn't on their payrolls.

hey guys, thanks for your messages. I will reread them and then
proceed, but first let me update. great weekend on the boat with no
problems. went to rockport,mass.
I have a couple of thoughts. first the inverter, it is a xantrex 1750.
I did install it myself, with 5ft 4o cables with a 250Ma fuse
(something like that, installed not in the engine compartment to keep
spars away from engine. I use the inverter mostly for 2 things. 1 a
900 watt microwave oven for 3 minutes or so at a time, and 2 a CPAP
machine, which I used to help me breathe when I sleep, so it is on for
7 hours or so. The CPAP machine worked OK last year with my 300 watt
inverter which plugged into the cig lighter, but that connection was a
joke. I have not worn the battery down to the point that it could not
start the engine in the morning. However, I ussally start the engine
with the other battery.
2- I have been told not to switch the battery switch while the engine
is running. this is something that I have been doing, My question is
if I ran down one battery and started the engine on the other, how to
I charged the weak battery without switching the switch while the
engine is running?
3- I have borrowed the battery tester and have a multi meter (not
digital, but I should invest in one)

tommorow, I plan to test the batteries by doing the following. Does
this sound right. First, turn battery switch to off, connect the
tester to battery one, push button on tester, hold for 10 seconds and
read. repeat for battery 2. Then turn battery switch to battery 1,
hook up tester to battery one, start engine and read the tester. turn
engine off, switch to battery 2, and repeat. this will help me decide
if battery or charger is working right.
this is where I will start. (keep in mind that I have made an
appointment with my regular boat mechanic for wed, but would like to
learn as much as possible before I have the pros take over. I
understand that removing the altenator is not to tough of a job. any
opinions? Thanks again for all your help.

On 18 Aug 2003 19:31:53 -0700,
(Richard Malcolm) wrote:

hey guys, thanks for your messages. I will reread them and then
proceed, but first let me update. great weekend on the boat with no
problems. went to rockport,mass.
I have a couple of thoughts. first the inverter, it is a xantrex 1750.
I did install it myself, with 5ft 4o cables with a 250Ma fuse

1750 watts plus the loss of conversion because it's not 100% efficient
will draw around 160-170 amps at full load. Yeah, I know, crazy isn't
it? That's the physics of it, anyways. So, you should WIRE it for
200 amps so you don't catch the boat on fire melting inadequate wiring
and POWER it with batteries that won't explode at a constant 200A
load.

Now that we both see that isn't reality in all but the large yachts,
the alternative is to limit the load on the existing batteries to a
much safer level than 1750 watts. Let's look at the microwave, the
biggest load. 900W at 12V...by the way, the more load you put on the
inverter, the lower the battery voltage drops, which makes the
inverter pull even MORE amps, lowering the battery voltage even
further in a downward self-destructive spiral caused by the voltage
regulation circuits in the modern inverters. 900W at 12V = 75A but
we'd better say 80A because the inverter isn't perfect. So, to be
safe, let's wire the inverter for a maximum 100A load on the battery
bank....for the 3 minutes you want it. We STILL have to wire it for
100A to the inverter. ANY wiring MUST be fused to protect the wiring
and the battery. This big inverter will EASILY blow the 100A fuse if
you go over 100A load on the battery.....when the wife plugs in the
1500W hair dryer, for instance.

On a short run to the inverter, the shorter the better, you can use #2
starter cable if you can keep the run down to a few feet. I highly
recommend the inverter be mounted as CLOSE to the house batteries as
possible because the big loss in cabling is on the 12V side, not the
AC side where the current is much lower. Buy an appropriate 100A
marine fuse to put next to the battery in an appropriate holder. West
marine has them that use the new spade fuses and seal from the water
intrusion. They mount with 2 screws on a bulkhead near the battery.

I see LOTS of dangerous, haywired, very powerful inverters drawing way
too much current through way too small cables that can burn the boat
to the waterline from simply drawing their rated currents. If anyone
ever tells you a battery exploded on a boat.....go have a look at what
the results are. Even if the wires survive, boiling the house
batteries IS very dangerous.

(something like that, installed not in the engine compartment to keep
spars away from engine. I use the inverter mostly for 2 things. 1 a
900 watt microwave oven for 3 minutes or so at a time, and 2 a CPAP
machine, which I used to help me breathe when I sleep, so it is on for
7 hours or so. The CPAP machine worked OK last year with my 300 watt
inverter which plugged into the cig lighter, but that connection was a
joke. I have not worn the battery down to the point that it could not
start the engine in the morning. However, I ussally start the engine
with the other battery.
2- I have been told not to switch the battery switch while the engine
is running. this is something that I have been doing, My question is
if I ran down one battery and started the engine on the other, how to
I charged the weak battery without switching the switch while the
engine is running?

There are many ways. The easiest way is a "battery isolator", which
is two huge diodes on a big heat sink to draw off the heat from them.
Diodes only conduct in one direction...from cathode to anode. So, how
they work is to connect both anodes to the + terminal of the
alternator and each separate cathode to each battery bank. This
isolator completely bypasses the battery switch. It's connected like
this:
-----anode--cathode------Battery 1+
|
alternator-----|
|
------anode--cathode-------Battery 2 +

The terminals on the device are marked alternator, battery1, battery2.
Current cannot flow from battery 1 to battery 2, or the other way
'round, because one of the diodes will be reversed bias and block it.
It's fully automatic and you cannot forget to set it because nothing
is to set.... Simply unwire the original battery output wire from the
alternator and wire the new one in. (Please disconnect BOTH ENDS of
the original wire as it will still be hot, otherwise, and use the same
heavy cabling to wire in the isolator the original wiring used.)

The other possibility is the ON-OFF switch bypassing the current
Battery 1 - Battery 2 - Both - OFF switch you now have installed you
shouldn't move when the engine is on. West Marine has these, too.
They are rated at 800A, bulkhead mount and look like the original
heavy battery switch with the big knob pointer on them.

This switch is wired with the same heavy cable used for the starter
from the BATTERY 1 to the BATTERY 2 posts on the original battery
switch, effectively hooking them together when this switch is ON. You
must remember to turn the switch OFF when the engine is not running.

What happens to the B1-B2-Both-Off switch is that between positions
the contact comes off both batteries, possibly leaving the raw
alternator hooked to the electrical system and putting 17-20V pulses
on them....in short, it makes a surge. The crossover switch between
them doesn't do this because no loads are hooked to it. It merely
connects one battery bank to the other....in the scenario we're
talking about, the good starting battery with the alternator on it, to
the dead house batteries, NEVER allowing the alternator to come off a
battery so this surge cannot happen. The alternator will then charge
the dead house batteries through the new switch ASAP as you drive.

3- I have borrowed the battery tester and have a multi meter (not
digital, but I should invest in one)

tommorow, I plan to test the batteries by doing the following. Does
this sound right. First, turn battery switch to off, connect the
tester to battery one, push button on tester, hold for 10 seconds and
read. repeat for battery 2. Then turn battery switch to battery 1,
hook up tester to battery one, start engine and read the tester. turn
engine off, switch to battery 2, and repeat. this will help me decide
if battery or charger is working right.
this is where I will start. (keep in mind that I have made an
appointment with my regular boat mechanic for wed, but would like to
learn as much as possible before I have the pros take over. I
understand that removing the altenator is not to tough of a job. any
opinions? Thanks again for all your help.

Sounds good to me. Good plan. If we're going to buy a meter, let's
buy a PANEL DC voltmeter for the battery switch! (PS - you don't HAVE
to pay $100 for a panel voltmeter if you don't tell your yachtie
friends and buy them from the NAPA auto parts store.) Real nice 2",
0-15VDC square panel meters, cat # 541-MSQ-DVV-015 are available from
Mouser Electronics (800-346-6873) for $20. At this price, you can
just buy 2 and hook one to each battery, permanently, and mount them
someplace nice so you can look at them as you pass. A panel voltmeter
draws microamps of power and would take 100 years to run down a boat
battery, not an issue at all. This will let you see what the
discharging battery voltage looks like under load, continuously
(around 11V dead - 13.8V charged), while the AC charger is on (about
14.2V fully charged) and while the alternator on the boat is charging
them (hmm...look....Battery 1 is 14.6V but Battery 2 is only 12.7V! I
musta forgot to switch on the crossover switch, again!)



Larry W4CSC

Maybe we could get the power grid fixed if every politician
regulating the power companies wasn't on their payrolls.

thanks again for your help. I will reread it until it all sinks in.
but for now, let me tell you what I did today. I did test both
batteries (one at a time with both load and while being charged) and
guess what, the baterries are with in normal limits, as defined by the
tesater, both with load and while being charged. I even left the
tester on while I cruised around for a couple of hours keeping and eye
on it at different speeds. all seemed fine. I did however check the
water and battery one (the one without the inverter)was low in all 6
channels. so I went to CVS and got some distilled water and filled
them up. So, I do not really know if the alternator or what is a
problem, but I do know that the 50 Amp circuit breaker, with one red,
one red/purple/ and one orange wire on the engine near the solinoid,
did trip twice this month. bad circuit breaker? spiking alternator?
battery needed water? bad connectors? still trying to find out, but
each day, I am learning a little more. thanks again
PS the fuse that I have on the invertor is a 250 anl. and the guage of
the wire is 4 aught.

On 19 Aug 2003 13:12:22 -0700,
(Richard Malcolm) wrote:

thanks again for your help. I will reread it until it all sinks in.
but for now, let me tell you what I did today. I did test both
batteries (one at a time with both load and while being charged) and
guess what, the baterries are with in normal limits, as defined by the
tesater, both with load and while being charged. I even left the
tester on while I cruised around for a couple of hours keeping and eye
on it at different speeds. all seemed fine. I did however check the
water and battery one (the one without the inverter)was low in all 6
channels. so I went to CVS and got some distilled water and filled
them up. So, I do not really know if the alternator or what is a
problem, but I do know that the 50 Amp circuit breaker, with one red,
one red/purple/ and one orange wire on the engine near the solinoid,
did trip twice this month. bad circuit breaker? spiking alternator?
battery needed water? bad connectors?

Ok, I have no idea how long it has been since these batteries were
properly watered, so can't estimate whether it's being overcharged or
not. Let's go boating for 20 hours before we pass judgement on them.
If you go cruising for more than 20 or 30 minutes, it might be
interesting to put your hand on the batteries to see how hot they are.
Overcharging wetcell batteries get REALLY HOT when they are being
overcharged. You can also take a look at them as soon as you shut the
engine down. Open the caps and look into the cells. Does it look
like it's boiling? A little percolation, occasional bubbles, is
normal. A rolling boil is not. What will happen to hard overcharging
is the plates will warp, and will melt the parts of the battery
holding it all together. If this happens, there's a good chance the
plates will short together INSTANTLY causing a battery explosion
spraying acid electrolyte all over the place. That's why all battery
boxes come with hold-down straps lazy people leave off because it's
too much trouble to strap them on and off. A battery box with a lid
sitting on it loose is useless confining the explosions.

A charging battery does use a little water, even in this modern age.
The plates aren't perfect lead and there is some gassification from
the impurities in it. But, if you run it 20 hours and find those
plates exposed again....you're definitely overcharging them....either
with the AC charger or the alternator. When you're not using the
boat, with the AC charger on them, keep an eye on the electrolyte
level monthly. Even the automatic shutoff chargers lose a little
electrolyte to gassification.

Sure glad for you the battery test came out good. You might just need
a new regulator. Don't hesitate to take the posts off the batteries
and CLEAN THEM with the steel brush post cleaner available at any
discount auto parts place. If any of the connections are loose, that
may be what tripped your fuse, too. When you're running, leave a 12V
light running you can see. It should light up brighter when the
engine starts and should be STEADY, not flashing
brighter/dimmer/brighter/dimmer. This would be an indication of bad
regulators, loose connections in the charging circuits.



still trying to find out, but
each day, I am learning a little more. thanks again
PS the fuse that I have on the invertor is a 250 anl. and the guage of
the wire is 4 aught.


Larry W4CSC

Maybe we could get the power grid fixed if every politician
regulating the power companies wasn't on their payrolls.

thanks again for all your help. I ran the boat yesterday for several
hours changing the battery tester from one battery to the other. I did
not notice any real heat comming from them, but I will check more
carefully now that I am aware of the overheating possibility. I think
that I will wait another day or 2 before trying to have my mechanic
work on it( if he even can) It is running fine right now and I enjoy
trying to figure out what is going on, I don't want the boat in the
shop for a week at this point if I can avoid it.(but I don't want to
damage the boat either) I will continue to reread your post and keep
working on it. Thanks again