Conference unifix::sailing

     Just thought I'd pass some information back around this. I finally
     bought a Surrete 100 Amp Hr battery (Group 27 size). I got a pretty
     good price from a small marine store in Portsmouth called OCEANFARE.

     The price was $65 (and no tax, it's NH), while Marine Exchange and
     Great Bay Marine were about $85. The rest of the stuff in in the 
     store pretty much sells for retail, and he doesn't have much in the
     way of hardware etc, but he's got a great price on batteries.

     /jim

    I have a Moorings 43 with 3 batteries.One is brand new and is only used
    to start the engine.The other two are worn,ie.won't hold acharge and
    they run the electronics,lights,etc.They are about 120 amp batteries.
    
    I have a price from Surrette in the $270 range and a price from Granite
    Electric for a Globe-Union Marine battery for $165.
    
    Does anyone have any experience with the quality of a G-U battery?
    Can you recommend a company that has "good" prices on batteries?
    Should I consider replacing two batteries with one,ie replace the two 
    120 amp batteries with one 200+ amp battery?
    
    Any suggestions?
    
    Regards, Tony            

    I have just purchased two Rolls batteries from a NH distibutor-S&S
    Supply in Kingston,NH on RTE.125.The specs meet or exceed Surrette and
    the price was better by 40%.

    
    
    re: .3
    
        Thanks for the suggestion.  I also bought a pair of Rolls batteries
        from S&S supply.  The sale is no longer in effect, but here are the
        specs, for future comparisons:
    
    Catalog#	GroupSize Plates/Cell Insul AH  Length Width Height Weight
    ----------  --------- ----------- ----- --- ------ ----- ------ ------
    60A16	24	  11	      PVC/G  90 10.25  6.88  8.88   52lb
    60A19	27	  13	      PVC/G 112 11.88  6.88  9.25   58lb
    60A23	31	  15	      PVC   119 13.00  6.88  9.25   -unkn-
    
    
        There are many others, but these are the most popular sizes
        for boaters.  I have a copy of the spec sheet if anyone would
        like more information.
    
        /Jim
    
    

    When shopping for new marine batteries the other day, the shop owner
    made an interesting observation.  We have three batteries.  One is
    isolated with its own switch and is used only to start the engine.  The
    other two are used for instruments etc. and are on when the engine is
    off as well as when it is on.  The engine starting battery is only on
    while the engine is running.
    
    The observation was that the engine starting battery is used much like
    a car battery in that it never has a chance to drain.  Soooo..why buy a
    deep cycle battery for that use when you don't really need it?  The
    other two batteries, no question.  Big 27's with 600 amps, deep
    cycle.  I guess I can't find fault with the reasoning as long as you're
    disciplined enough to turn it off when the engine goes off.  Any
    thoughts?  (I KNOW you must have a viewpoint, Alan!)
    
    Dave

    My only thought is that you may use the starter battery in an emergency
    (i.e. all other batteries wiped). So then you may want a deep cycle.
    
    Gregg

    If all other batteries have failed, you'd WANT to start your engine -
    ergo an automotive type.
    
    Adam

re .5:

Right, Dave! I see no point whatsoever in a battery dedicated to engine
starting. We use deep cycle batteries for both engine starting and
ship's power. From the data I have and my experience in starting our
engine, a deep cycle battery is quite capable of starting a diesel
engine (at least the small diesels we have). See note 843.23. The only
possible advantage to having a dedicated starting battery is that you
are rather more certain you'll have a fully charged battery for starting
the engine. But this could also be achieved by simply having a third
deep cycle battery. Make that extra weight earn its keep. Or install a 
low voltage alarm so you don't fully discharge the batteries.

A useful idea: Starter motors draw high currents. Most battery to 
starter motor cables are rather small. The result is a significant 
voltage drop in the cables, which means that a deeply discharged battery 
will not be able to start the engine. Heavier cables are both expensive 
and not very flexible, which makes them hard to install. We use two #1 
gauge cables in parallel from the batteries to the starter motor and 
from the batteries to the engine block. Two paralleled #1 gauge cables 
is somewhat better than a single #00 gauge cable and less costly. I got 
the #1 gauge cables at my friendly local automotive parts store. Off the 
shelf items. Engine starting is much easier now and the engine can be 
started even when the batteries are way down. 

> Right, Dave! I see no point whatsoever in a battery dedicated to engine
> starting
    
    Racing safety regs. ( ORC Cat.?? ) state that if it is not possible to
    start the engine by hand, then the boat must carry a battery which
    is used solely for that purpose.
    
    Chris
    

re .9:

If you're racing, you must follow the racing rules, but (IMHO) the 
racing rules are not always goodness or to be followed. The rules also
specify, eg, that a boat may carry only a minimal amount of fuel and
water, amounts I would consider imprudent and unsafe for a long passage.
Many if not most of the offshore racing safety requirements are excellent. 

    The result is that we will get the deep cycle battery for engine
    starting even though the guy's argument was pretty good.  Cost is about
    $15 more for the deep cycle.  Figure in relationship to the other costs
    involved, it's nothing!  But the argument is a good one.
    
    When the other two batteries run low, we always start the engine (in
    nuetral ofcourse if racing!) rather than switch to the third battery.
    
    Alan, I like the idea of the two cables.  Is voltage drop an issue if
    they are both attached to the battery with the terminals "stacked" one
    on top of the other with the wing nut on top?  Wouldn't think so, but I
    defer to your experience.
    
    Dave

re .11 and two cables:

We have three batteries and two switches. A schematic diagram would be 
easier, but I'll try words. Remember that voltage drop is proportional 
to cable length.

One end of two #1 gauge cables connects to the ground post of battery
one and the other ends to the engine block. These are long cables
(probably 60"). A short (12" or so ) #1 cable connects the ground post
of battery one to the ground post of battery two. (That's a total of 
three heavy cables connected to the ground post of battery one.) Another
short #1 cable connects the ground post of battery two to battery three. 

The battery switches (vapor-proof Cole-Hersee) are mounted just above 
the battery boxes. Short (12" or so) #1 cables connect the battery 
positive posts to the switches. A short #1 cable connects the common 
terminals of the switches. A long (72" or more -- maybe as long as 96")
#1 cable is also connected to the common terminal of each switch. The
other ends of these cables are connected to the starter motor solenoid.
By selecting the appropriate switch position, all possible combinations
of one, two or three batteries can be used for engine starting. Three
quite discharged batteries in parallel will still likely start an
engine. 

A #2 cable is connected to the common post of one of the switches. This 
cable feeds the circuit breaker/power distribution panel. Again, all 
possible combinations of one, two, or three batteries can supply ship's 
power. 

We've used this arrangement for eleven years with no problems at all. 

In the past, the alternator output was connected to the ship's power 
cable. This allowed charging any one or all of the batteries at the same 
time. Of course, with the arrangement it is possible to disconnect the 
alternator from the batteries with the engine running -- now see the 
note on repairing alternators. Just make it an absolute rule to never 
change switch positions while the engine is running to avoid destroying 
alternator diodes. Or use a Cruising Equipment Zap-Stop or Ample Power 
Snubber across the alternator output. 

Now that I've installed a 100 A alternator with an adjustable regulator
with battery voltage sensing, the alternator will be always connected to
all three batteries through a diode isolator. The volage drop in the
isolator diodes is not a problem since the alternator voltage regulator
senses battery voltage, not alternator output voltage. Our puny OEM
alternator (maybe 25 A on a cold day) is now an emergency spare. I'm
anticipating that the time required to fully recharge our batteries will
be reduced by a factor of three or more. I've also used some of the
standby pay DEC graciously gave me to buy three Prevailer gel batteries.
I'll let you know if they're worth the extra cost in five years or so. 

In reference to .12--

Allen,

I agree, you will have greatly improved charging performance with 
your new equipment. For most people whose boats have a 40-50 ampere 
alternator, an adjustable regulator is about all that is needed 
to improve their recharge problems. Also, your point about 
the regulator monitoring the voltage at the battery rather than at the 
alternator is important and one that people who rebuild their charging 
systems for better recharge time should observe.

Joe

    Alan, your setup sounds quite good and is similar to the one we had on
    Wildside.  However, on Harrier, we have a different layout.
    
    The starter battery is isolated with its own switch that powers the
    starter panel.  Two other batteries go to another switch by the nav
    station to power the instruments.  Not ideal, but in compliance with
    racing rules.
    
    This weekend we put in fresh batteries, hooked them up, turned the key
    and...nothing.  We get power to the starter panel but somewhere between
    the panel and the starter motor it disappears!  We tested the starter
    button switch and even shorted it.  No juice.  We ran out of time to
    test and will resume the hunt next weekend.
    
    Dave

    If you have a Volvo Penta and using diodes to separate multiple
    batteries,you have to modify the regulator for compensating the 0.7
    Volts lost by the isolator diodes.This is easy done.Remove the
    regulator from the alternator.There is a small wire coming out of the
    plastic.Just cut this wire and you are all set.The alternator is now
    delivering 15.0 Volt instead of 14.3 Volt.
    
    Peter

re .14:

    
>>>    This weekend we put in fresh batteries, hooked them up, turned the key
>>>    and...nothing.  We get power to the starter panel but somewhere between
>>>    the panel and the starter motor it disappears!  

We had this problem a couple of times many years ago. In our case the 
internal contacts in the starter motor solenoid were corroding to the 
point they wouldn't conduct (the bare copper contacts were covered with 
green). I had the contact silver-rhodium-gold plated and the problem has 
not reoccurred. Worth the $75.

Alan

re .12:

A preliminary report on my new Ample Power 100A alternator and 
regulator:

WOW! FANTASTIC! Ample Power makes several high output alternators, one 
of which is designed for rather low engine and alternator speeds. This 
is the one we have. The output of our OEM alternator never much exceeded 
25A, even with the batteries fairly deeply discharged. At engine speeds 
of 1200 to 1500 rpm, the Ample Power alternator was putting 75A into our 
less-than-half discharged battery bank. As the batteries recharged, the
charging voltage stayed at 14.24 volts plus/minus 0.01. Turning on power
using devices (eg bilge pumps) resulted in the alternator output current
increasing and the charging voltage staying constant -- the net charging
current into the batteries stayed about the same. The constant charging 
voltage is user adjustable to meet the requirements of various battery 
types. After the batteries are recharged, the alternator output drops 
to a constant (but again adjustable) float voltage. So far I like the 
Prevailer gel batteries -- they have a higher voltage than conventional 
batteries (about 12.9 volts at full charge and 12.3 volts at 50% charge) 
and have a higher recharging rate. 

Installing the alternator, regulator, isolator, digital voltmeter, two 
current shunts, and making the alternator mounting brackets was several 
days work. So far very much worth the effort. 

    Does anybody have any experience with a marine gel battery called
    "Dynasty" made by Johnson Controls?  These are Prevailer type
    batteries.  I saw an article somewhere, maybe in Practical Sailor, some
    time ago about these new batteries.  An advantage the Dynasty offered
    was that they came in standard automotive dimensions.  This would be an
    advantage to me as I currently have three Die-Hards in standard battery
    boxes.  It would be difficult for me to install larger Prevailer
    batteries from a space standpoint.
    
    Also, if I go with a gel battery do I need to upgrade my charging
    capability, ie. alternator etc.?  Most of our sailing is two to four
    days away from our dock where shore power is conected to a three bank
    battery charger.  Each year we may take a one or two week trip where we
    would need to use the engine for charging.
    
    Chuck

The comparison between the Johnson Controls batteries and the Prevailers 
was in a fairly recent issue of Practical Sailor. The Prevailer DF180 
batteries are a standard automotive size, others may not be. The DF180 
is rated at 85 amp-hr and is more or less the replacement for the usual 
100 amp-hr deep-cycle battery.

I would infer from the installation instructions that came with my Ample
Power alterntor and regulator that an alternator with a standard,
non-adjustable automotive regulator perhaps should not be used with gel
type sealed batteries. Proper charging and float voltages vary with
temperature. At 77 deg F a gel type battery should be charged at 14.20
to 14.25 volts and floated at 13.69 to 13.80 volts. A liquid electrolyte
battery should be charged at 14.45 to 14.50 volts and floated at 13.75
to 13.80 volts. Charging a gel type battery at higher than recommended
voltages will result in an overly high charging rate, which is not
likely to improve battery life. Note too that gel type batteries have a
higher charging current at a fixed charging voltage. Alternators without
current limited output will supply as much current at the batteries will
accept. There is a real risk of destroying your alternator. Two less
than half-discharged Prevailer DF180 batteries will happily take 70
amps from my alternator. 

I'd suggest talking to the experts at Ample Power and Cruising Equipment
before buying gel type batteries without replacing your alternator and
regulator. 

One more interesting point: The voltage required for a given charging 
current decreases with increasing battery temperature. Alternatively, 
the charging current increases with increasing battery temperature for a
fixed charging voltage. This can lead to thermal runaway if you have a
big alternator. The charging current increases the battery temperate
which increases the charging current which increases the battery
temperature which ........ can eventually destroy the batteries and even
cause a nasty fire. This scenario becomes more likely if a battery is 
damaged (eg, a shorted cell). 

The Ample Power regulator senses battery temperature and decreases the
charging voltage with increasing battery temperature to reduce the
chances of thermal runaway. This is one reason I bought this regulator. 
For even more money, Ample Power has a regulator with current limiting. 

    During a week's outing, I experienced power problems with batteries
    that are less than two years old.  The house battery is a 4D deep cycle
    and the other has two 80ah standard marine batteries in parallel.
    
    The culprit was the 4D.  Although it would take a charge and the SG was
    constant, it would never get above about 1.125...and the electrolyte
    was gray in color.  Water level was never a problem.  What would cause
    the gray color?  The lack of good charge on the other bank I assume was
    due to the bad battery taking most of the charge from the isolator.
    
    I bypassed the isolator and just charged the two in parallel, and they
    worked ok.
    
    I put in a Dynasty 4D last Friday (126lbs...a real fun job).  One
    concern I had was it is marked on the battery to use a charger with a
    taper charge of 35A max.  I called Pro Mariner and asked for their
    input on using my 50A charger with the GEL battery.  They indicated the
    real issue is not to let the voltage get above 14.2 for the GEL's and
    they have had no problems with their chargers which are set at 14.08.  
    
    I am considering a modification to my charging circuit to run a wire
    from the alternator to the starter (short run, same as connecting to
    common on the battery switch) which will allow bypassing the isolator
    for either battery by using the switch.  Thus the house battery will
    get the 14+V from the alternator while the other bank will get a
    maintenance charge from the isolator (13.3V).  Since it is a
    backup/starting battery, it should not get very low.
    
    The Dynasty has a five year prorated warranty with the first year a
    full replacement.  
    
    Hank

re .last:

Hmmm, I'm not sure what you're suggesting is a good idea. Conventional 
batteries and gel-type batteries have significantly different charging 
requirements (see note 272.19). A least one major vendor (perhaps Ample
Power) strongly recommends against having both types aboard. To fully
recharge a conventional battery requires a charging voltage high enough
to potentially damage a gel-type battery and/or the alternator (the
charging current will be excessive). Depending on temperature, a
gel-type should be charged at something like 14.24 volts and a
conventional battery at something like 0.2 to 0.3 volts more (this is
from what I recall from the installation instructions for my Ample Power
alternator/regulator). The float voltage should be around 13.6 for a
gel-type (at this voltage the charging current for our gel-type
batteries drops to maybe an ampere). 13.3 volts will be too low to
maintain full charge. If you set the charging voltage for the gel-type
battery, you'll undercharge the conventional batteries and shorten their
life considerably. 

I'd suggest getting Ample Power's catalog and application notes and 
discussing what you intend with them. Another drawback to what you're 
proposing is that it isn't simple -- it sounds like putting the switches 
in the wrong position could cause major problems. One thing I really 
like about our revised system is that it is simple. Once the engine is 
started, all of the batteries are (fully) charged automatically. The 
battery switch only selects which of three identical batteries supplies 
ship and engine starting power. Since the alternator is always connected 
through an isolator to all three batteries, changing the battery switch 
position shouldn't cause any failures or problems. Our system is now 
fairly idiot-proof -- it certainly wasn't before.

Alan

re .12:

The normal way to wire batteries and battery switches is to use one
battery switch for every two batteries. In this scheme one battery is
connected to switch terminal #1 and the other battery to switch terminal
#2. The common terminal of the switch is connected to the main power bus.
All electrical devices (eg, engine starter motor, VHF, autopilot, etc)
are supplied from this main power bus. 

This scheme has some advantages:

1. It is the usual way, so everyone understands it.

2. It requires only one (rather expensive) battery switch for every two 
   batteries.

It also has some disadvantages:

1. The voltage on the main power bus can drop very significantly 
   (easily to under 8 volts) when starting the engine. This low voltage 
   will, among other things, cause most if not all loran receivers to lose 
   the loran signals (crash) and force the loran receiver to reacquire them. 
   This can take several minutes, which is always annoying and in a crisis 
   may be a serious problem. 

2. When the starter motor is turned off, the collapsing magnetic field in 
   windings can create a voltage spike on the power bus high enough to
   damage electronics (eg, loran, GPS, autopilot). This is not likely, but
   it reportedly does happen. 

There is an alternative way to wire the battery switches that overcomes 
these disadvantages, assuming, that is, that you have at least two 
batteries. 

Use one battery switch per battery. Connect the common terminal to the 
battery. Connect terminal #1 to the main power bus. Connect terminal #2
to the starter motor. The usual practice is to have only one battery
connected to the main power bus at a time. Assume that this is battery
1. To start the engine, turn the switch for battery 2 to the 2 position.
Now the starter motor is drawing current from battery 2 while battery 1
continues to supply the main power bus. The voltage on the main power
bus is independent of the voltage of the battery supplying the starter
motor, so no loran crashes and no starter motor voltage spikes on the main
power bus. 

But ...... you have to connect all of the switch #1 terminals together
and all of the switch #2 terminals together, which adds more wiring. To
charge all of the batteries you have to either be sure the battery
switches are in the "1" or "both" position (assuming that the alternator
output is connected to the main power bus) or use a diode isolator
(which is a good idea anyway). This second scheme still allows using any
combination of batteries for the starter motor and to supply the main
power bus. 

We've used the usual scheme for the last many years, but this winter I'm
rewiring to use the second scheme since our loran does crash when starting
the engine and does have a longish (re)acquisition time. 

Alan

        I have a 2-3 year old Interstate 30 Marine battery on our Catalina 22
        which is used solely for electronics. This past winter, I failed to
        maintain the water level in the battery while charging, and discovered
        the level down to only 25%. I refilled the battery with distilled
        water and recharged for a day.

        This spring, all worked well for a week or so, then some electronic
        gear starting acting up. Within a month, the battery was dead. It
        receives a charge from a small alternator on the outboard which is
        putting out.

        Any suggestions on whether the drying out I put the battery through
        caused permanent damage to it, or whether it can be revived.
        Someone suggested replacing the battery acid and have the battery
        go through several full charge and discharge cycles.

        Dan
      

    I believe your low water caused the damage.  Since your use is in
    marine service and battery reliability is important I wouldn't mess
    around trying to restore the battery.  Its probably badly sulfated.
    
    If you want to try and restore it dump the acid out of all the cells.
    Refill the battery with DISTILLED WATER and charge it at a low rate
    1 to 2 amps until you have charged it to its amp hour capacity.
    i.e. 100 AH hours @ 2 amps = 50 hours charging.  Then dump the 'water'
    out, and refill the battery with 1.260 sp grav. electrolyte.  
    
    Jeff

    .25 wont work- if you dump out all the remaining fluid and refill with
    distilled water you wont have a battery at all- no electrolyte. You can
    buy battery electrolyte in any good automotive store. Replacing the
    electrolyte MIGHT restore the battery.
    
    If you want to try this, and live anywhere near Framingham MA give me a
    call. Ill give you a container of electrolyte. I bought it to use as a
    pickle for silver soldering copper boilers, but its to weak an acid  
    for that use. 

    Dumping out the electroyte is NOT INTENDED TO GET THE BATTERY TO WORK
    WITH DISTILLED WATER IN IT.  It is intended to be a 'neutral' medium
    for the LEAD SULFATE to dissolve in while the battery is on slow charge
    as explaned in .25.  WHEN FINISHED WITH THE SLOW CHARGE INTO DISTILLED
    WATER ONE DUMPS THE WATER OUT AND RESTORES THE ELECTROLYTE WITH NEW
    1.265 electrolyte.
    
    Jeff

re .17:

In the spring of 1991 we replaced the OEM battery charging system on our 
boat with an Ample Power 100A alternator and regulator. We also 
installed three new Prevailer DF180 85 A-hr gel batteries.

Since then we have been careful to never discharge the batteries more 
than 50% of their capacity and have tried to keep them as fully charged 
as possible at all times. 

In the spring of 1994 I did some battery capacity testing using a
constant load (3A) that I designed. All three batteries had a capacity
in the 75 to 80 A-hr range. 

In 1995 we added a 25W solar panel to augment the engine-driven 
alternator and to provide battery charging during the week. The panel
kept all three batteries fully charged except during our vacation. Even 
then it supplied (in sunny weather) much of our electrical needs. 

This spring I bought another 85 A-hr gel battery, a West Marine-labelled
Prevailer. (This gives us about 300 A-hr of total battery capacity,
about 150 A-hr at 50% discharge.) I repeated my 1994 battery capacity
tests. The worst of the three batteries purchased in 1991 still has about
88% of the capacity of the new battery (82.9 A-hr) and the best about
92%. Prior to installing the Ample Power system we were fortunate to get
five years of use from a battery (conventional wet design high quality 
deep-cycle) and by then it was badly degraded and had maybe (guess) at
most 50% of its original capacity and probably less. 

All in all, my conclusion is that the investment in the Ample Power
alternator and regulator and associated voltmeter and current shunts was
an excellent one. I'm most pleased with the results, especially with not
having to spend $300 to $450 for new batteries in the foreseeable 
future.

Alan