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The ugly weather this week sure did give me a set-back to hopes of an early Spring! Too bad... I'm still hoping! In fact, in order to give that "extra" push to an early Spring, you will start receiving the GLSS RODE SHOW on a weekly basis -- every Monday.
Mark your calendars for March 26. That's the date of the annual GLSS Spring Safety Seminar. It's at North Start Sail club and it starts at 7:00 PM. I'm looking forward to meeting the 130 people that this RODE SHOW goes out to!!!
So, we're still counting them down: The 20 top steps to get ready for the Mackinac Solo Challenge. What's that you say: "Where are the other steps??" Visit the GLSS website: http://webhost.sailnet.com/glss so you can get the true scoop from past RODE SHOW's and other Solo Sailing information.
Step #14 - Evaluate Your Electrical System
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The electrical system on the boat is just like the collection basket at church: "Put it in if you got it. Take it out if you need it." Now...the dangerous outcome from this simple observation may be the number of malted beverages that could be consumed as you try to argue the fine points of this comparison with Father O'Malley!
The reason listed most often for pulling out of the Mac Solo is electrical failure. Therefore, it is worthwhile to spend some time ensuring that your electrical system is performing as designed. If you look at your favorite marine equipment catalog, you will notice some high-end pricey electrical monitors that you could purchase and install. But be careful here. You might be spending the big bucks to hire Arthur Anderson to tell you that your church is bankrupt! You're probably better off to put ol' Arthur on the sidelines, and spend the money on a few card tables so you can have a bake sale. Besides...you'll have more fun.
Go to your favorite Radio-Shack-type store and buy a digital volt-amp meter. (Make sure that it can read volts to the hundredth. And make sure that it can read at least 10 DC amps.) Read the owners manual and be ready to refer to the section that describes parallel for reading volts, and series for reading amps.
Now, go to your boat. Shut off everything in your electrical system and set your new meter to read amps. Then go to your battery and disconnect everything from your negative battery terminal. Connect your meter in series between your negative battery terminal and anything that was connected to it. Your ammeter should read zero (since you previously shut off everything.) If your ammeter doesn't read zero, this means that you've got some sticky fingers in the collection plate! Start disconnecting "stuff" until you find your amp leak. (Ahhh...if Father O'Malley only had it so easy!)
Now let's check out the batteries. (I'll focus on the traditional lead-acid type.) Top-off your battery cells with distilled water. A turkey baster works great for this. Shut off your electrical system, and turn on your battery charger. Bring your batteries to a full charge. Once fully charged, shut off everything and let your battery sit idle for at least 30-minutes. Set your new volt-amp meter to read volts, then read the voltage across your two battery terminals. A fully charged lead-acid battery should read about 12.70 volts.
It's now time to turn "stuff" on and find out what your battery has under the hood. Turn on whatever you plan to use: Speedo, VHF, Wind Instrument, Running Lights, GPS, etc. In addition, turn on a cabin light to simulate the power draw from your autopilot. Let this set-up run for two hours, then shut off everything. Let your battery sit idle for at least 30-minutes before you read the voltage across your two battery terminals. Always read your battery voltage under no-load conditions after 30-minutes idle. (Let's assume for this example that your reading was 12.63 volts.)
Aficionados of lead-acid batteries live and die by one big rule: "Use only the top half of your battery capacity." This rule maximizes storage capacity as well as extends years of service. The voltage of a lead-acid battery at half-capacity is 12.20 volts. (Don't confuse lead-acid with NiCad batteries. It is best to run a NiCad all the way down to maximize storage and extend service life.) Now it's time to buy your favorite 6th grader a Big-Mac in return for the answer to this problem: "If it takes 2 hours to go from 12.70 volts to 12.63 volts, how long will it take to go to 12.20 volts." This answer gives you the number of hours that you can run your chosen electronics before recharging your battery.
So. We've talked about the amps going out. And we've talked about how many amps you can store. But how do you get those dog-gone amps back in? "And that's my big problem, too!" says Father O'Malley! "I've always got trouble filling up the basket!"
Your alternator, in conjunction with your voltage regulator, is the typical method for recharging marine batteries while at sea. If you can, pull your alternator off the boat and take it to your favorite boat-shop or auto parts store. Ask them to bench test it. They'll be able to tell you if your alternator and regulator are running to their specifications. Chances are that they're okay. If you need replacement parts, insist that they are USCG approved. Marine engine compartments are designed to have explosion-proof electronics - auto engines are not. Re-install the alternator on your boat with a new v-belt.
You've got to wait until you're in the water for this part. Get your new voltmeter and prepare to run the reverse scenario as compared with running the battery down. Start with your battery at half-capacity, 12.42 volts. Turn your "stuff" on as before. While at the dock, idle your engine and let your battery charge for one hour. Then shut off everything. Let your battery sit idle for at least 30-minutes before you read the voltage across your two battery terminals. This final volt reading allows you to estimate the charging time required to refill a specific amount of battery capacity (or voltage). Unfortunately, this method will not predict the capacity that you might have if you were to charge for an additional hour. You'll have to run a 2-hour charging test to determine the capacity gained from running that additional hour. Standard voltage regulators put most of the capacity into the battery early in the charging cycle. The charge rate decreases as your battery starts taking on additional capacity. (Check out your favorite marine catalog for options regarding fancy (smart) voltage regulators.)
There you go. After a few adult beverages, both you and Father O'Malley find yourselves with more and more in common: Put it in if you got it. Take it out if you need it. Get rid of Arthur Anderson. Have a bake sale.
Find the leaks. "I'm starting to get fired up!" says Father O'Malley. "How can I find out more about this solo sailing stuff?" "It's easy!! Come to the GLSS Spring Safety Seminar and Open House on March 26 at North Star Sail Club."
Stay tuned... The next RODE SHOW will be out one week from today.
Whaddyathink Step #13 is? (I already have it written!!)
Respectfully yours,
Patrick Nugent