Posted by Bruce in alaska on June 11, 2010, 12:13 am
> Nearly always. There are boats built to run on A.C. but usually the
> big ones and they generally have a gen set running contentiously.
>
> Occasionally you come across a 24 VDC system but again that is unusual
> as nearly all "boat gear" is built to run on 12 VDC so having a 24
> volt system entails a step down system to run the 12 volt stuff.
>
> Cheers,
>
> John B.
> (johnbslocombatgmaildotcom)
I am familiar with a vessel that has NO BATTERIES anywhere onboard. This
is a River Tug, designed to be left unattended, on the Yukon River, all
winter, and then reactivated in a few hours in the spring. The twin Main
Engines are Air Start, as is one of the twin Big Gensets. the other Big
Genset has both Air and Hydraulic Starters, and the Small Genset has
Hydraulic, and Inertial Starters. When the Crew returns in the Spring,
they start the small Genset FIRST. Usually with the Inertial Starter. It
is like a BIG Flywheel that you wind up with a Crank. Once the Flywheel
is spinning a a good clip, you give the Intake Manifold a small shot of
ether, and engage the Starter. Usually you only need to wind it up once
for a start. Once the small Genset is running, It is just big enough to
run the Twin Big Gensets Intake Manifold Heaters and the Air
Compressor, that charges the Starting Air Tanks. When Air Pressure in
the Air Tank is up, one of the twin Big Gensets is started, which can
supply power for the whole vessel, Heat, Lights, and run all the
machinery. When I was there, the whole startup procedure took less than
20 minutes, and the Mains were online, inside an hour. The Hydraulic
Starters are very simple, in that you have a 2 Foot long handle, that
you pump, back and forth, until the Pressure Gauge reads in the Green,
and shows Good Pressure in a Tank. That feeds the Hydraulic Starters on
one Big Genset and the Small Genset. You just open the valve that feeds
the Starter, and that spins up the engine. Never have a problem with
Dead Batteries.
--
Bruce in alaska
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Posted by John B. slocomb on June 11, 2010, 11:29 am
wrote:
>> Nearly always. There are boats built to run on A.C. but usually the
>> big ones and they generally have a gen set running contentiously.
>>
>> Occasionally you come across a 24 VDC system but again that is unusual
>> as nearly all "boat gear" is built to run on 12 VDC so having a 24
>> volt system entails a step down system to run the 12 volt stuff.
>>
>> Cheers,
>>
>> John B.
>> (johnbslocombatgmaildotcom)
>I am familiar with a vessel that has NO BATTERIES anywhere onboard. This
>is a River Tug, designed to be left unattended, on the Yukon River, all
>winter, and then reactivated in a few hours in the spring. The twin Main
>Engines are Air Start, as is one of the twin Big Gensets. the other Big
>Genset has both Air and Hydraulic Starters, and the Small Genset has
>Hydraulic, and Inertial Starters. When the Crew returns in the Spring,
>they start the small Genset FIRST. Usually with the Inertial Starter. It
>is like a BIG Flywheel that you wind up with a Crank. Once the Flywheel
>is spinning a a good clip, you give the Intake Manifold a small shot of
>ether, and engage the Starter. Usually you only need to wind it up once
>for a start. Once the small Genset is running, It is just big enough to
>run the Twin Big Gensets Intake Manifold Heaters and the Air
>Compressor, that charges the Starting Air Tanks. When Air Pressure in
>the Air Tank is up, one of the twin Big Gensets is started, which can
>supply power for the whole vessel, Heat, Lights, and run all the
>machinery. When I was there, the whole startup procedure took less than
>20 minutes, and the Mains were online, inside an hour. The Hydraulic
>Starters are very simple, in that you have a 2 Foot long handle, that
>you pump, back and forth, until the Pressure Gauge reads in the Green,
>and shows Good Pressure in a Tank. That feeds the Hydraulic Starters on
>one Big Genset and the Small Genset. You just open the valve that feeds
>the Starter, and that spins up the engine. Never have a problem with
>Dead Batteries.
Sure you can do that. I don't know whether they make them any more but
airplanes used to have hand cranked inertial starters. I even started
a R-3350 on a B-29 once to see whether they really worked and they do.
A gas plant I built used gas starters, like an air starter but powered
by the gas stream.
And I'm pretty sure that you can still buy spring starters. Used to
use them some in the oil field. No sparks. You cranked a shaft on the
back of the starter that wound up a big spring inside the starter.
After you got it wound then (you had to hold your mouth just right)
you pulled the starting lever and whoosh (if you were lucky) it
started. Used in areas where there might be gas. No generators or
batteries to cause an explosion.
In fact I saw one of these on a sailing yacht engine - maybe 40 H.P.
Cheers,
John B.
(johnbslocombatgmaildotcom)
Posted by Jim Wilkins on June 11, 2010, 12:16 pm
> ...
> And I'm pretty sure that you can still buy spring starters. Used to
> use them some in the oil field. No sparks. You cranked a shaft on the
> back of the starter that wound up a big spring inside the starter.
> After you got it wound then (you had to hold your mouth just right)
> you pulled the starting lever and whoosh (if you were lucky) it
> started. Used in areas where there might be gas. No generators or
> batteries to cause an explosion.
> In fact I saw one of these on a sailing yacht engine - maybe 40 H.P.
> Cheers,
> John B.
> (johnbslocombatgmaildotcom)
When I was a kid we had a lawnmower with a wind-up spring starter.
Fortunately it had a rope drum backup for whenever the spring or
ratchet broke.
jsw
Posted by John B. slocomb on June 12, 2010, 1:02 am
On Fri, 11 Jun 2010 05:16:00 -0700 (PDT), Jim Wilkins
>> ...
>> And I'm pretty sure that you can still buy spring starters. Used to
>> use them some in the oil field. No sparks. You cranked a shaft on the
>> back of the starter that wound up a big spring inside the starter.
>> After you got it wound then (you had to hold your mouth just right)
>> you pulled the starting lever and whoosh (if you were lucky) it
>> started. Used in areas where there might be gas. No generators or
>> batteries to cause an explosion.
>>
>> In fact I saw one of these on a sailing yacht engine - maybe 40 H.P.
>>
>> Cheers,
>>
>> John B.
>> (johnbslocombatgmaildotcom)
>When I was a kid we had a lawnmower with a wind-up spring starter.
>Fortunately it had a rope drum backup for whenever the spring or
>ratchet broke.
>jsw
Apparently the manufacturer is alive and well as I found this
http://www.springstarter.com/
Cheers,
John B.
(johnbslocombatgmaildotcom)
Posted by Martin Riddle on June 12, 2010, 8:06 pm
> vaughn wrote:
>>>
>>> One problem could be caused by shading of one panel while the other
>>> has full
>>> sun.
>>
>> That would be much more of an issue for series panels than parallel.
>> Panels
>> usually have blocking diodes installed internally, so a shaded panel
>> simply
>> contributes little or no charge current, but causes no problems.
> That's an interesting scenario. I would think the shaded series panel
> would still conduct most of the current being generated by the others,
> so the total power loss would be about the same as in a parallel
> setup.
> That hypothesis may be completely out to lunch, so if it starts to
> really bother me, I'll get the ammeter out.
> mike
PV panels are current sources. Not voltage sources.
Cheers
> big ones and they generally have a gen set running contentiously.
>
> Occasionally you come across a 24 VDC system but again that is unusual
> as nearly all "boat gear" is built to run on 12 VDC so having a 24
> volt system entails a step down system to run the 12 volt stuff.
>
> Cheers,
>
> John B.
> (johnbslocombatgmaildotcom)