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Thread: electrical budget??

  1. #1
    Join Date
    Sep 2007
    Location
    Vancouver British Columbia, Canada
    Posts
    133

    Default electrical budget??

    OK so I finally took a look at the electrical budget worksheet.......I will of course fill in some of the blanks but only hope that this is the kind of test I cannot 'fail' !!!

    However, as I see it I can not (truthfully) complete this to reflect what may, or may not, get either consumed or produced while sailing from San Francisco to Hanalei.
    -Which drive unit am I going to use with the AP??
    -Or will the windvane happily steer the boat all the way?
    -What will cloud cover be, and how much will my new solar array REALLY produce.
    -Maybe they will get washed off the boat again??
    -I trust engine will start and alternator charge when requested, but maybe they won't.....

    I do not question the purpose of the worksheet, (probably a good way to make people think about their electrical usage) but wonder at the necessity of inflicting it upon this group of sailors. Everyone, I am sure, is aware that whatever power they consume must be somehow replaced - but this is only common sense and anyone whom has gone far enough down the road to get to the beginning of this event must have already figured that out for themselves.

    Isn't that what the qualifying cruise is supposed to get them started thinking about???

    What may be more helpful is to ask them what they will do if the on-board electrical system suffers catastrophic failure halfway there - then what??? They lose charging ability, storage capacity, or suffer an electrical fire.... A lightning strike, anyone???

    Do they have a plan for that???? How exactly do they get the boat across a thousand miles of ocean and find a safe harbour - at that point, probably not even Hanalei Bay??

    Surely they must have a workable solution to this scenario apart from pulling the string on the EBIRP??? Yet without a little foresight, planning and the right equipment available, perhaps that may be what some would resort to.....

    Comments????

    Jim/Haulback

  2. #2
    Join Date
    Sep 2007
    Posts
    134

    Default

    I think you're right, I don't think you can 'fail' the energy worksheet except by failing to fill it out. I have yet to fill mine out, I'm getting my alternator repaired and don't know how the repaired unit is going to work until I try it out. Seems the old one got overheated at some point and the windings degraded, or so I'm told.

    But you raise a couple of interesting points. How would we cope with *total* electrical failure, as from a lightning strike which fries every electronic piece of equipment, handheld or not. At that point even navigating becomes difficult, no distance or speed log (how many of us are going to carry a backup taffrail log?), no time signals even if you happen to have a sextant. (Head south until you get to the proper latitude then go west, just like the old time sailing ships before accurate longitude!). Hopefully everyone is carrying their required non-electronic compass. (I wonder if a lighting strike can wipe out the magnetized needle?)

    I carry a backup handheld GPS wrapped in tinfoil (Faraday cage) and in a waterproof container so hopefully even in the worst circumstance it will still work, but who knows? I seem to recall Tiger Beetle uses his oven as a Faraday cage for handhelds, which also sounds like a good idea unless you decide to preheat it without checking inside first!

    As for the EPIRB, another good question. I don't think I would ever set one off unless I was sitting in the liferaft and the boat was at the bottom. But I wonder, when do you notify the coast guard you are having problems and may be in danger? If I'm on a boat that may go down at any second, it would be nice to have the coast guard know where my last position was in case the EPIRB fails. On the other hand, as long as there's a chance of saving the boat, I don't want the coast guard to show up and start demanding to 'rescue' me. I'm sure it's somewhat of a catch-22 for the coast guard as well, since they could be accused of being negligent if they don't respond and someone loses their life as a result.

    I seem to recall one of the previous TransPacs, where a competitor lost use of her SSB and couldn't be accounted for for several days. Someone shoreside overreacted, saying we had 'lost contact' with one of our racers and notified the coast guard. The coast guard then started making noises about search and rescue. At least that's vaguely how I remember the story. But you can see how the coast guard can be put in a position of 'damned if you do, damned if you don't', and is going to err on the side of overreacting, rather than underreacting. So it's something to keep in mind before making a call.

    - Mark
    Last edited by Alchera; 03-27-2008 at 11:01 AM.

  3. #3
    Join Date
    Sep 2007
    Location
    San Francisco Bay Area
    Posts
    2,095

    Default

    Hmmm...."Faraday Cage" I wonder if an old metal (unused) paint can would work as a Faraday Cage for my backup GPS and the handheld radio.

    A lightning strike CAN destroy a magnetic compass. Also a lightning strike can magnetize a lot of the previously non-magnetic metal in the boat, thereby making the compass act totally whacked out. This happens in airplanes pretty often.

    Windvanes don't depend upon electrons to steer. That's the REAL reason I use one.

    As for the electrical budget, I think Jim has a point, but on the other hand the RC needs to go to some sort of lengths to ensure that people have at least thought about major issues, and filling out the form and seeing if there's some glaring discrepancy can't hurt. It's pretty painless. Of course, it only makes sense to have backups.

    Regarding electrical systems....I've said this a million times so here goes a million and one. In 1996 I got to Hanalei on two fully charged batteries and a four-hour charge run with my Lightning generator on about day 12. I had no solar panels. I carried a LOT of AA and C batteries!

    The GPS's were all handhelds.
    The Navik windvane did the steering.
    I didn't use Navigation lights, but I did have a masthead strobe.
    Other strobes in the rigging were armband strobes.
    I didn't talk to anybody for 16 days on the radio.
    I essentially never ran cabin lights.

    That taught me a lesson. You can go a LONG way with a totally dead house electrical system if you just have independent systems that don't depend on house electrons to run the boat.
    1968 Selmer Series 9 B-flat and A clarinets
    1962 Buesher "Aristocrat" tenor saxophone
    Piper One Design 24, Hull #35; "Alpha"

  4. #4
    Join Date
    Sep 2007
    Posts
    59

    Default

    Are lightening storms common in July where we'll be going? Is this like sailing back East in the summer?

    - Tom K Feral

  5. #5
    Join Date
    Nov 2007
    Location
    Monterey
    Posts
    6

    Default Faraday Cages

    You guys have probably already discussed this, but I just can't find where so I'll throw this in for redundancy. Faraday cages are shaped like that diamond plate screen thing that hangs in your paint bucket to roll off the excess paint. Your best/cheapest protection available against lightning are the anti-static-faraday bags we use to ship motherboards and hard drives. If you go into any local computer shop that builds computers, they've got these laying all over the place and you should be able to pick up 3-5 at $2-3 ea(max) if not FREE. Double bagging a spare GPS in these before putting into a waterproof, all vinyl, no metal bag, while not clipping it to anything metal on the boat is your safest protection against lightning, static, RFI signals, or EMP. Remember there are 2 kinds of anti-static bags. The mirror-mylar-foil looking type and the one you want, the clearer diamond-cagey looking bag. Guaranteed? No. Better than nothing, Yes. Recycled, reusable, and the excitement of free!

  6. #6
    Join Date
    Sep 2007
    Posts
    99

    Default

    Hi All,

    I think everybody is pretty attuned to LED runnig and anchor lights and even LED flashlights. What I did in addition to all of the above is I got some LED Puck Lights for backup cabin lighting when I only want a little light or if the main electrical system suffers a complete catastrophic failure. Costco had them for $12 for 3 and West Marine sells them for $10 each (their typical profit margin). They run on 3 triple A cells which I will have about 4000 of. I have also converted all of the cabin interior lights to LED (red/white) but they do run off the main electrical system. Finally, I have a gimbaled Weems and Plath kerosene lantern.

    As for lightening, I will do what I do at home and camping. If there is a storm nearby I will disconnect the radios completely and hope for the best. I speculate that if you are hit directly, fire and sinking will be your primary concerns and then survival whether in the raft or boat. I do carry and sorta know how to use a sextant and have several mechanical watches, so should be able to tell where I am roughly should all the GPS's, digital watches and the Loran fail. Two of the watches have built in Flux Gate compasses. Hitting the islands with no compass and no means to find even rough position would be problematic. Were I in this position, I would surely head back for the West Coast. It would be hard to miss that and it would be easy to find out where on the West Coast you were once you got there.

    If you have an emergency, you are always better off if you have thought it through and have a plan. This gets you started and gives you breathing room. You can then reassess the plan and see if, under the circumstances, you can come up with a better one. Most of this sort of planning ahead for emergencies comes from flying. If you have an emergency in the air at several hundred miles an hour, you don't have time to ponder the possibilities, read up, call for advice, etc. you better know what you are going to do ahead of time.

    Anybody out there ever been hit by lightening in a boat or know anybody that has? If yes, did handhelds, GPS's, digital compasses etc fail? If yes to the above, did anybody have handhelds in ovens or antistatic bags that survived when all else failed? I have never heard of read about anyone losing all their handheld electronics in a small boat due to lightening at sea, but I'm sure it must have happened at least once in history.

    Remeber Joshua Slocum went around the world singlehanded with a sextant and a clock with only an hour hand............

    John H
    Dream Chaser

  7. #7
    Join Date
    Sep 2007
    Location
    37.205346,-121.963398
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    788

    Default Faraday cage ? Use aluminum foil.

    Just wrap it in foil and be done with it. That is a great faraday cage. You could do slightly better with silver foil .

    Brian

    Quote Originally Posted by ScottJ View Post
    You guys have probably already discussed this, but I just can't find where so I'll throw this in for redundancy. Faraday cages are shaped like that diamond plate screen thing that hangs in your paint bucket to roll off the excess paint. Your best/cheapest protection available against lightning are the anti-static-faraday bags we use to ship motherboards and hard drives. If you go into any local computer shop that builds computers, they've got these laying all over the place and you should be able to pick up 3-5 at $2-3 ea(max) if not FREE. Double bagging a spare GPS in these before putting into a waterproof, all vinyl, no metal bag, while not clipping it to anything metal on the boat is your safest protection against lightning, static, RFI signals, or EMP. Remember there are 2 kinds of anti-static bags. The mirror-mylar-foil looking type and the one you want, the clearer diamond-cagey looking bag. Guaranteed? No. Better than nothing, Yes. Recycled, reusable, and the excitement of free!

  8. #8
    Join Date
    Jan 2008
    Location
    On board 'Nereida' when possible - in S.Africa just now
    Posts
    33

    Smile Lightning strike....

    Quote Originally Posted by John Hayward View Post
    Hi All,


    Anybody out there ever been hit by lightning in a boat or know anybody that has? If yes, did handhelds, GPS's, digital compasses etc fail? If yes to the above, did anybody have handhelds in ovens or antistatic bags that survived when all else failed? I have never heard of read about anyone losing all their handheld electronics in a small boat due to lightening at sea, but I'm sure it must have happened at least once in history.

    John H
    Dream Chaser
    Hi John - Yes - "Nereida" was hit by lightning crossing the Bay of
    Biscay to NW Spain - VHF aerial at top of mast was 'frizzled', all instruments toasted - including handheld GPS (off) in grab bag - 'dead as a Dodo'! Half an hour spent checking boat out, getting out & deploying emergency VHF antenna in case radio was working, allowing for drift and large 'circle of error', then had ship's compass and plotted position from 20mins prior to strike on paper chart to use to head SW hoping to keep clear of all dangers in deep water as headed on with very basic navigation!! Interestingly, depth readout was still there & seemed to be vaguely of the right order, according to paper chart, although temp readout on same instrument was showing stupidly high. Never could see any evidence of where lightning exited....
    Eventually had Spanish fishing boat confirm position in daytime so we didn't miss coming inshore to get to La Coruna & head on unwittingly around Cape Finisterre instead! I expected handheld GPS to be OK but most definitely was not - circuit board was burned out! Ever since, handheld GPS and a computer is wrapped in Al foil & put inside (metal-lined) oven as a 'double Faraday cage' if lightning is around.... I know people who think that carrying 2-3 PCs and no paper charts is OK.... go figure!

    Cheers,
    Jeanne
    "Nereida"
    Trinidad (leaving for Panama Monday... keep your fingers crossed for my transit being timely...)

    www.svnereida.com
    Jeanne "Nereida"

    www.svnereida.com

  9. #9
    Join Date
    Sep 2007
    Posts
    99

    Default

    Hi Jeanne,

    Good luck on a speedy transit through the canal! Rumor has it they have reduced the number of small boats they let in at one time and it's clogging things up a bit. Hope it's not true.

    Thanks for the story! Great testament to paper charts and farraday cages. Well we hope the farraday cages would do for lightening protection for PC, handhelf GPS and VHF. Did your primary VHF survive or did you just yell back and forth to the fishing boat?
    Also, were any of your compasses adversely affected. I wouldn't be at all surprised to hear that the magnetic field of the boat was changed rendering the compasses simewhere between suspicious and worthless.

    Thanks Again,
    John
    Dream Chaser

  10. #10
    Join Date
    Jan 2008
    Location
    On board 'Nereida' when possible - in S.Africa just now
    Posts
    33

    Default Lightning strike (part2)

    ... OK.. my 4th attempt - can I throw my computer out of the hatchway once I've finally posted this reply...???!!! Why does dragging my finger over the touchpad cause oblivion???? I digress.....

    Hi, John!

    I don't think rigging the emergency aerial achieved anything (later found the frizzled remnant of the aerial at top of mast - I still have the memento onboard!) -radio was replaced along with all instruments and radar (insurance covered it!). Certainly, the only two boats seen either couldn't hear or had their radios switched off - a French guy waved cheerily as he went on his way and a Spanish fishing boat was attracted by 'SOS' signals on foghorn and by torch/flashlight. Impressive the way their only 'English-speaking' crew member (think his English was only minimally better than my 3-4 words of Spanish!) jumped on to "Nereida" without any damage to her, despite their flared topsides and the big swell running at the time! I can't actualy remember if handheld VHF was used or not, but I'm sure that got replaced also.
    Main compass seemed fine - I've no recollection of ever hearing of anyone whose main compass went down in a strike - I'd be interested to hear if anyone has heard differently. Didn't have an electronic fluxgate handheld at the time (I'd expect that to go down if not wrapped in metal foil) and didn't bother even looking at other 'basic' handheld (since main compass was fine) - but that's clearly OK now so must not have been affected then. Of course, when storm passes, you might have the moon or odd star out to keep steering your course by....
    I would have expected that since the ionizing influence of the lightning around is a temporary phenomenon, the constant Earth's magnetic field would probably keep (electrically isolated) magnetic compass needles unchanged - any physicists out there who'd like to argue the point?? (I'll be off the Internet whilst on passage this week but would be interested..)
    Can I start a new thread on a totally different topic - I've just spotted a gecko on board - anyone know how to catch or get rid of one without killing it??

    Cheers,
    Jeanne
    "Nereida"
    Jeanne "Nereida"

    www.svnereida.com

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