Shore power questions
Richard
questions I'm hoping the group can help answer.
I have a 2001 Regal 2550 LSC, which does not have shore power. The
boat has two 12 volt batteries which power a marine refrigerator,
fresh water pump, salt water (raw) water pump, AM/FM Radio and CD
player, Marine radio, and the typical cabin and cockpit lights.
Obviously, without shore power, all this equipment runs off the
batteries...which seems to me to be quite a drain when the motor is
not running. I've spent the night on the boat (tied up in a slip at
the marina) which has 30 and 50 amp shore power connections and would
like to take advantage of the power available.
My questions are as follows. Is it possible to purchase a 30 amp
shore power cord and adapter(s), and simply use these like an
"extension" cord to to connect to a mult-outlet surge adapter (with a
master switch)? My thougths are that this would allow me to plug in a
small TV, air-conditioner, coffee maker, etc. while tied to the dock.
In addition, I could also utilize a battery charger to replenish the
on-board batteries as needed. Does the use of shore power require any
special equipment, or is it simply plug and go?
Next question. Assuming I can't just plug in as described above,
what's would you folk recommend for adding shore power? Is there such
a device (an inverter perhaps) that would take the shore power
connection and provide a continuous charge to the batteries, as well
as providing a couple of outlets for 110v equipment?
Final question. I've gotten a quote from my dealer to add the shore
power, and it seemed quite a bit on the high for the labor and
equipment they were quoting. If I simply give in and let them put the
system in, what should I expect it to cost?
I appreciate the help....thanks.
Richard
"Reel Busy"
Terry K
A 20 amp circuit should be ground fault interruptor protected on the
dock. A battery charger and household outlet can be wired close to
the cable entrance. More outlets may be easy or difficult,
dependant on cabinet work. Any regular electrician could wire it up.
You will need to chop a hole for the cable connector / entry box
somewhere convenient. I suggest that if mine didn't lie in the
cockpit and close by the docklines, I would have towed my dock with
it by now.
Continue to use your 12V stuff, and maybe a nice little toaster oven
or convection microwave, too. Electric hot water is not beyond
reach.
Terry K
Steve
requirements for installation aboard a boat. Not necassarily the same as in
a house.
Steve
s/v Good Intentions
Richard
point :). I do have one quick question regarding charging the
batteries using an automotive battery charger. I have used an
automotive charger to replenish the charge before. However, I only
did this while the boat was on the trailer (after running the onboard
devices for quite a while). I completely disconnected the batteries
prior to charging, and connected them one at a time. Do you see a
problem with this arrangement?
TIA
On 17 Sep 2001 03:26:54 GMT, ka...@FS.Denninger.net (Karl Denninger)
wrote:
>The biggest problem with shore power installation (or anything else) in a
>boat is the lack of access afforded by most "modern" builders.
>
>My older Hatteras is better than most newer boats in this regard - which
>doesn't say all that much, actually. I still have to be a monkey to do some
>things and get to some systems - fortunately, not often and not too many
>systems.
>
>You SHOULD do this right and install a true marine system. There are a lot
>of reasons for this when you're talking about 110VAC systems - not the least
>of which is safety. Water and AC power are a bad combination if not done
>right.
>
>True marine-rated cable is expensive. But you absolutely do need it,
>especially for AC circuits. High resistance will start FIRES; don't skimp
>on the wiring.
>
>There may be other choices than your dealer to do this kind of installation.
>But in any event you are talking about making at least one good-sized hole
>in the boat (for the shore inlet), securely mounting the appropriate items
>(converter/charger, wiring, etc) and proper fault protection to keep both
>your property and life safe.
>
>I feel qualified to do AC (and DC) wiring on my boat, and do so. I follow
>ABYC standards when doing that work; you do need to know "the rules" to
>do a safe and proper install, but its definitely doable with some knowledge.
>
>For AC however, if you're unsure (and it appears you are) get professional
>help. If not your dealer then someone elese who is qualified.
>
>I DO NOT recommend using a common battery charger on an extension cord.
>
>That is EXTREMELY DANGEROUS; common automotive style chargers are typically
>not fully isolated from the line and a fault can easily electrocute you
>or someone else either on board or in the water near the vessel, not to
>mention causing serious electrolytic corrosion.
>
>--
Terry K
with a trusted tech.
Do it yourself.
Terry K
Richard
are wired in parallel. The charger is a decent automotive charger. I
there were only 1 battery, I'd simply flip the battery switch to off,
then charge it. Because there are 2, I just assumed I'd need to
disconnect them from each other prior to connecting the charger :).
Like I said, I appreciate the advice!
On Tue, 18 Sep 2001 06:08:35 GMT, Terry K <tksp...@nbnet.nb.ca>
wrote:
Jere Lull
> Yeah...I think those beers would be handy about now. The batteries
> are wired in parallel. The charger is a decent automotive charger. I
> there were only 1 battery, I'd simply flip the battery switch to off,
> then charge it. Because there are 2, I just assumed I'd need to
> disconnect them from each other prior to connecting the charger :).
>
> Like I said, I appreciate the advice!
You don't need to disconnect them for charging and we regularly charge both of ours
in parallel -- that's what your engine probably does-- but I sure hope you have a
separate starting battery. It's too easy to run a bank (of 1 or 100) batteries down
and if that's the only bank you have, it's time to call for a jump start. If you
don't have a separate starting battery, I'd recommend hooking them together through
a battery switch.
Most boats have a 1-2-both-off switch, but I chartered an interesting setup: The
starting battery is directly connected to the charger and starter. The house bank
goes directly to the panel and can be paralleled to the charging system with a
simple on/off breaker. When charging, that switch is set to on. the rest of the
time, it's off. If someone throws the switch at the wrong time, it's not going to
trash an alternator the way turning off the usual switch would. [kids will be
kids....]
Having woken up to dead batteries too often, the setup has some appeal.
--
Jere Lull
Xan-a-Deux -- '73 Tanzer 28 #4 -- out of Tolchester, MD
Xan's Pics & Specs: http://members.dca.net/jerelull/X-Main.html
Our BVI Vacation trip FAQ (250+ Annotated pics):
http://members.dca.net/jerelull/BVI.html
Peggie Hall
out of the boat. But do NOT put an automotive charger in your engine
compartment. You can leave the battery in the boat to use one, but it
must remain on deck, away from any gas fumes....'cuz the electrical
components in automotive chargers are not spark protected.
Peggie
Peggie Hall
> My questions are as follows. Is it possible to purchase a 30 amp
> shore power cord and adapter(s), and simply use these like an
> "extension" cord to to connect to a mult-outlet surge adapter (with a
> master switch)?
You can buy regular shore power cords at most boat stores...they come in
10' or 15', 25' and 50' lengths. If you're gonna carry one with you, buy
a short one. They're not cheap though.
I THINK you can also do this (it works in reverse): you can also buy a
"pigtail" that connects a shore power connection to a regular extention
cord. The question is...shore power cords are male at the end that plugs
into the connection on the dock, female on the end that plugs into the
boat. Most people that keep our boats in slips have one so we can run
power tools etc from a shore power connection. However, I don't know if
the pigtails are also available with a female connection so you can plug
it into the boat and an extention cord from your house to to power it.
If you can, you have the equivilant of a shore power connection at home
on a trailer. I may be all wet, but it's worth checking out.
Btw...the fridge is the biggest 12v power hog on your boat. The power
draw for everything else combined doesn't equal the fridge. If you turn
it off at the breaker when you go to bed on an anchor--after you're sure
nobody's gonna open it again till morning--your batteries will last a
LOT longer. Also...save the fridge for food...keep your beer and soft
drinks--the things people keep opening the fridge all day long to
get--in a cooler. The less a fridge door is opened, the less time the
compressor has to run and the less battery power it will eat up.
And finally...lessee--small TV, air conditioner, coffee maker etc...on a
25' boat. Where are you gonna PUT all that stuff? :-)
Peggie
w_tom
fail, you just lose a battery. However marine units are more expensive for good
reason. What happens when the charger +12 V output goes 180+ volts? That is
excessive voltage looking for alternative paths such as your gasoline tank? A
decent marine battery charger contains, at a minimum, an overvoltage circuit that
operates independently of the charger. Once triggered, the overvoltage circuit
shorts that battery charger output until the charger is disconnected either by
human or by a blow fuse. Does that inexpensive auto battery charger have any
such circuit. Often not.
The connection from boat through charger connects boat electronics to an
expanded overhead array of wires. There are a number of considerations in
marine units that make the 120 VAC installation and battery charger more
complicated. Again, it is why 120 VAC is more expensive that you might suspect.
Most auto battery chargers simply dump high voltage into the battery to a
faster charge. It is possible to overcharge a battery if connected too long.
Same is true of trying to recharge multiple batteries simultaneously. If one
battery becomes fully charged before another, then the first battery is damaged
by continued charging. Generally, this is not a problem if both batteries are of
same condition - same age, type, and use. One way to avoid overcharging one
battery is to use a slower charger that never exceeds the 13 volt recharge
limit. This lower voltage means all batteries recharge slower, but that no one
battery in parallel is overcharged. One such type is trickle charging.
Auto battery chargers are not necessary sufficient as DC power supplies. They
tend to output noisy power that can be a problem for some boat appliances. That
is not just the electronics. Some battery chargers can damage some DC motors.
Depends on how cheaply the battery charger really is made since batteries
themselves are not so picky about voltage quality. Again notice that marine
battery chargers tend to be more expensive - again for good reason.
Gary Schafer
automotive charger. Number one is that it is probably not explosion proof. Meaning
that it may have a switch or circuit breaker in it that could ignite gasoline fumes
if it were in the boat. Or could ignite the gasses from the battery when it is
charging.
Second, not all automotive chargers are well isolated from the ac line. Some could
energize the boat with 120 volts ac through the battery ground system. If clipping
the charger leads to the battery, you must always unplug the charger before
connecting or disconnecting the battery clips. If you do not you will get a spark
that could ignite the gasses from the battery. This is especially true if you have
just finished charging the batteries.
A slower charger that only puts out 13 volts will never fully charge a battery. Also
a trickle charger can overcharge a battery.
A lot of marine battery chargers charge in the same way as automotive chargers. Just
a single diode (half wave rectifier). Some can be noisy but a lot of marine chargers
that use triacs to switch and regulate the voltage are much noisier than most
automotive chargers. As far as this "noisy power" causing problems with motors and
other items on the boat, it is usually not a problem. The battery is a big filter. It
smoothes out the large pulses from the battery charger.
However most automotive chargers are not voltage regulated. If left on too long they
will overcharge the battery and ruin it. But the same charger left on a car battery
too long will have the same effect.
A charger that is to be left connected to the battery needs to be voltage regulated.
Regards
Gary
Richard
Rosalie B.
you state 1, 2, both, off. When we live aboard, we've formed the habit of
switching from the active bank to the other bank just before we start the
engine in the morning. Since it was hard to remember whether we'd switched
or not, Bob decided to do the odd-even day thing. If he looks at the date
on his watch and it is an even day, he switches to the #2 bank. Simple and
easy to remember (at least as long as his watch works, and I guess he could
always ask me if it wasn't working).
Our batteries are up in the cockpit combing and since the hydrogen
offgassing problem (which really only occurs in the last part of the charge
cycle) puts out gas that's much lighter than air, there's no chance of it
getting into the bilge or engine room with the alternator. And we have a
diesel engine, so there's no gasoline vapors down there either.
Jere Lull <jere...@bellatlantic.net> wrote:
>Richard wrote:
>
>> Yeah...I think those beers would be handy about now. The batteries
>> are wired in parallel. The charger is a decent automotive charger. I
>> there were only 1 battery, I'd simply flip the battery switch to off,
>> then charge it. Because there are 2, I just assumed I'd need to
>> disconnect them from each other prior to connecting the charger :).
>>
>> Like I said, I appreciate the advice!
>
>You don't need to disconnect them for charging and we regularly charge both of ours
>in parallel -- that's what your engine probably does-- but I sure hope you have a
>separate starting battery. It's too easy to run a bank (of 1 or 100) batteries down
>and if that's the only bank you have, it's time to call for a jump start. If you
>don't have a separate starting battery, I'd recommend hooking them together through
>a battery switch.
>
>Most boats have a 1-2-both-off switch, but I chartered an interesting setup: The
>starting battery is directly connected to the charger and starter. The house bank
>goes directly to the panel and can be paralleled to the charging system with a
>simple on/off breaker. When charging, that switch is set to on. the rest of the
>time, it's off. If someone throws the switch at the wrong time, it's not going to
>trash an alternator the way turning off the usual switch would. [kids will be
>kids....]
>
>Having woken up to dead batteries too often, the setup has some appeal.
grandma Rosalie
Lloyd Sumpter
<jere...@bellatlantic.net> wrote:
> Richard wrote:
>
>> Yeah...I think those beers would be handy about now. The batteries are
>> wired in parallel. The charger is a decent automotive charger. I
>> there were only 1 battery, I'd simply flip the battery switch to off,
>> then charge it. Because there are 2, I just assumed I'd need to
>> disconnect them from each other prior to connecting the charger :).
>>
>> Like I said, I appreciate the advice!
>
> You don't need to disconnect them for charging and we regularly charge
> both of ours in parallel -- that's what your engine probably does-- but
> I sure hope you have a separate starting battery. It's too easy to run a
> bank (of 1 or 100) batteries down and if that's the only bank you have,
> it's time to call for a jump start. If you don't have a separate
> starting battery, I'd recommend hooking them together through a battery
> switch.
>
> Most boats have a 1-2-both-off switch, but I chartered an interesting
> setup: The starting battery is directly connected to the charger and
> starter. The house bank goes directly to the panel and can be paralleled
> to the charging system with a simple on/off breaker. When charging, that
> switch is set to on. the rest of the time, it's off. If someone throws
> the switch at the wrong time, it's not going to trash an alternator the
> way turning off the usual switch would. [kids will be kids....]
>
> Having woken up to dead batteries too often, the setup has some appeal.
>
Sounds like an interesting setup. I was going to make a similar system
in my truck, which had a separate battery in the back for lights, stereo,
fridge, etc. I was gonna get a solenoid that was switched in and out by
the ignition - turn the ignition on, connect the two batteries together.
Off - they're separate.
Sold the truck before I got around to building it...
Lloyd Sumpter
"Far Cove" Catalina 36
Lloyd Sumpter
used a good-quality outdoor extension cord for "shore power" on both the
Venture 22 and the Cal 25 for over 10 years without a problem. I used it
mainly for a light, small heater, etc. (making sure I stayed within the
15A limit of the cord). I did use a cheapo automotive battery charger,
but IIRC I disconnected the ground in it. If you want to be safe,
disconnect the battery when you're charging it.
Just keep the connections away from water, and you should be OK. (and
it's a REAL good idea to ensure the "shore power" connection has a GFI
(Ground-fault interrupter). That will blow if there's any grounding
problems.
Lloyd Sumpter
"Far Cove" Catalina 36
In article <9o3qhu$bvk$0...@dosa.alt.net>, "Karl Denninger"
Lloyd Sumpter
<ka...@fs.denninger.net> wrote:
> Many automotive chargers do not have an isolation transformer in them -
> they actually couple the neutral side of the line to the negative post!
> Disconnecting the "safety" ground in such a charger does nothing to help
> you.
>
> A fault in one of those can lead to a ground path back through the boat
> and/or water, and can be LETHAL in a boat.
>
OK - I'm standing on the fibreglass sole of my cabin, and there's a
phase-to-ground fault in the charger (only one phase, so can't be
phase-to-phase). The current goes back up the attached neutral, and
the breaker blows.
If the neutral isn't properly grounded, and "floats" a bit, connecting it
to the case of the charger (which is connected to the ground lead) will
short out the voltage. If there's a GFI, it would blow, but otherwise it
would just heat up the wires a bit.
f you plugged it in backwards (can't do it because of the 3-pronged
plug) or the plug is wired backwards, you'd be shorting the hot to ground,
and blow the breaker. If the ground wire isn't connected, but the case is
connected to the BOAT's ground and therefore to the water, the effect
is the same: the current would rather flow through the case and the
grounding than you (and the low resistance would probably blow the
breaker as well)
If the case of the charger isn't connected to ANY ground (ground
wire or water), and you manage to plug it in backwards, and neutral IS
connected to the case, the case would then be "hot" compared to ground,
and would be very dangerous. But this is the case in your garage, too,
which is why we have the ground wire (or polarized plugs).
It must be late at night, and I'm tired, because I can't see how a
charger in a boat is any more dangerous than a charger in my garage when
it's raining out. Can you explain it, please?
Lloyd Sumpter
Protection and Control Design, BC Hydro
Terry K
>
> Karl Denninger wrote:
>
> > Many automotive chargers do not have an isolation transformer in them -
I have never seen one so designed, nor do I think I would want one.
> > they actually couple the neutral side of the line to the negative post!
> > Disconnecting the "safety" ground in such a charger does nothing to help
> > you.
> >
> > A fault in one of those can lead to a ground path back through the boat
> > and/or water, and can be LETHAL in a boat.
> >
>
> OK - I'm standing on the fibreglass sole of my cabin, and there's a
> phase-to-ground fault in the charger (only one phase, so can't be
> phase-to-phase). The current goes back up the attached neutral, and
> the breaker blows.
>
> If the neutral isn't properly grounded, and "floats" a bit, connecting it
> to the case of the charger (which is connected to the ground lead) will
> short out the voltage. If there's a GFI, it would blow, but otherwise it
> would just heat up the wires a bit.
>
> If you plugged it in backwards (can't do it because of the 3-pronged
> plug) or the plug is wired backwards, you'd be shorting the hot to ground,
> and blow the breaker. If the ground wire isn't connected, but the case is
> connected to the BOAT's ground and therefore to the water, the effect
> is the same: the current would rather flow through the case and the
> grounding than you (and the low resistance would probably blow the
> breaker as well)
>
> If the case of the charger isn't connected to ANY ground (ground
> wire or water), and you manage to plug it in backwards, and neutral IS
> connected to the case, the case would then be "hot" compared to ground,
> and would be very dangerous. But this is the case in your garage, too,
> which is why we have the ground wire (or polarized plugs).
>
> It must be late at night, and I'm tired, because I can't see how a
> charger in a boat is any more dangerous than a charger in my garage when
> it's raining out. Can you explain it, please?
>
> Lloyd Sumpter
> Protection and Control Design, BC Hydro
IF the earth, our dirt, and the water that rests upon it, is
connected to one side of the hot circuit, ie, 'neutral', then the
whole world becomes one of the 2 connections required to induce
current through your body. Only one additional contact is required,
any hot connection will do.
Insulating f/g hulls, or good rubber soles may save your life if you
suffer one of a number of faults in electrical equipment, but the
threat is originally presented by the fact that your very own dirt
has been co-opted by the hydro company to serve as part of the
distribution system, even if, as presently employed, it is only
intended for reference, and as a 'safety feature'.
If every earth connection in the universe was disconnected, there
would be far less likelyhood that you could be electrocuted by
running over your electric extension with your electric lawn mower,
or by swimming up to an aluminum boat or a through hull on a boat
where the battery charger continues to work, more or less, even with
one or two wires abraded completely through as the extension cable
rests on the gunnel, or from simple flexural failure or corrosion.
If every ordinary electrical circuit were wired as a bifilar
circuit, with no assumption of any reference to earth whatsoever, we
would be safer in our bathtubs than we are now, and there would be
no need of GFCI devices. Electrical equipment not perfect would
simply stop, and you could handle any one live wire safely, naked,
soapy, barefoot in the rain, whatever. There would be no tendancy
for the ground, OUR dirt, to bite you.
Neutral need not be connected to earth for multiphase systems to
work.
We cannot own the dirt, it owns us. We have no right to electrify
it.
Lloyd, you may be in a position to explain why the power co. seems
to need the 'earth' connection. Would it be fair to say the it is a
'legacy' problem to disconnect it? Or is it simply the expense? Or
is it the GFCI manufacturer's lobby?
Terry K
Ian Malcolm
Any fault to earth from a floating system would result in the other conductor
becoming potentially lethal. However people would have the idea that its 'safe'
to touch one wire. If your neibour touches the other wire while you are
touching one, you BOTH die! The lawyers would have a field day. With the
present system, if you are dumb enough to bypass any protection fitted and dont
repair damaged insulation, it's your own fault if you get killed. Also, a
severe earth fault on neutral is low risk and on live will blow the fuse instead
of making the opposite conductor live without anyone noticing.
IMHO leave it how it is onshore but make marinas use an individual isolation
transformer for each pontoon without a hard ground connection, but rigged with a
circuit that detects leakage to ground from either wire and disconnects the
pontoon and sounds a loud alarm. People will keep their electrics safe if they
know they will get a $100 bill for tripping the earth leakage breaker and the
marina will isolate that berth and get the power back on if they are making
money off it. Unfortunately you cannot count on people's sense of self
preservation to get them to do the necessary maintenance for safety, but the
worst offenders usually like to preserve their wallet!
--
Ian Malcolm. London, ENGLAND. (remove NOSPAM from email to reply)
Peter Bennett
wrote:
>Lloyd Sumpter wrote:
>>
>> Karl Denninger wrote:
>>
>> > Many automotive chargers do not have an isolation transformer in them -
>
>I have never seen one so designed, nor do I think I would want one.
>
Perhaps in the dim distant past, some battery chargers were built with
autotransformers, but I can't believe that such a charger would pass
CSA/UL/other safety approvals in the past 40 years or so.
This seems to me to be an old wives (mechanic's) tale that has no
foundation.
--
Peter Bennett, VE7CEI
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver-webpages.com/van-ps
Lloyd Sumpter
Bennett" <pet...@interchange.ubc.ca> wrote:
> On Sat, 29 Sep 2001 16:15:34 GMT, Terry K <tksp...@nbnet.nb.ca> wrote:
>
>>Lloyd Sumpter wrote:
>>>
>>> Karl Denninger wrote:
>>>
>>> > Many automotive chargers do not have an isolation transformer in
>>> > them
>>> > -
>>
>>I have never seen one so designed, nor do I think I would want one.
>>
>
> Perhaps in the dim distant past, some battery chargers were built with
> autotransformers, but I can't believe that such a charger would pass
> CSA/UL/other safety approvals in the past 40 years or so.
>
> This seems to me to be an old wives (mechanic's) tale that has no
> foundation.
>
>
Not only that, but it's WAY easier to built a full-wave rectified
charger using a center-tapped secondary. An autotransformer would mean
either a REALLY awful rectification or more cost for the AC-to-DC
conversion.
All the cheapo chargers I've seen use CT secondary. (But often they
solder a wire from the AC ground and DC negative to the case. Also
sometimes the neutral to the case. But these can easily be disconnected
to give you a floating system)
Jere Lull
> We have two banks, and not a separate starting battery. The switch is as
> you state 1, 2, both, off. When we live aboard, we've formed the habit of
> switching from the active bank to the other bank just before we start the
> engine in the morning. Since it was hard to remember whether we'd switched
> or not, Bob decided to do the odd-even day thing. If he looks at the date
> on his watch and it is an even day, he switches to the #2 bank. Simple and
> easy to remember (at least as long as his watch works, and I guess he could
> always ask me if it wasn't working).
I find this a bit backwards. We try to start on whatever we're switched to in the
morning. If it doesn't start the engine, we switch to both. [If we had two "identical"
banks, we'd always charge with "both".]
After charging is done, we switch to the other bank.
If we were to switch from the active to the inactive bank before starting the engine,
it'd put us on the previous night's drawn-down bank, which is sometimes flat if we'd
done a lot of reading/partying.
This way, we start the evening with two fully charged banks and have a known good bank
in reserve for the morning.