Mike S
ENERGY BUDGETS, BATTERY USE & RECHARGING DEAD BATTERIES
Mike V's story was very well put. Was that heresy or hearsay? I don't know.
But follow this logic: Once you've got a good large house bank, and you've done all the wiring upgrades, and you've checked all your connections and you've got the monitoring system and you regularly check your distilled water levels, and you have a handle on everything, including your energy budget, and you either frivolously use or be miserly with your energy usage, what do you do next?
You learn about the steadily diminishing law of returns of how your engine driven alternator can replenish your batteries, regardless of whether it puts out 30 amps from the stock regulator, or 55 to 80 amps from a high powered new alternator with an external regulator.
We learned that this summer on our cruise (knew it already but saw it in action for the first time
).
Page 46, Figure 2-13 of Calder's covers it well. Start out with full house bank, in our case 315 amp hours, from charging at our friend's dock. Spent two hours sailing, 20 nanoseconds motoring to our first anchorage. Stayed there two nights, less than three days. 315 less say 60 times 3 = 180 = 135 ah left. (Using fridge and lights "frivolously"). Motored 6 hours the next day. Input equals say 30 amps per hour, put back in 150. 150 + 135 = 285. (We get a good 30 amps input from our stock alternator because we still have our AutoMac.) Anchored out for three nights, turned off the fridge at night. 285 left less (3 x 30) = 195 left. Motored four hours = 30 x 4 = 120 + 195 = back to 315. On the hook for two more nights frivolously = 315 less 120 = 195. Sailed for a day, little motoring. 195 - 60 = 135.
This could go on and on until we plugged in again, and without motoring for long periods of time, would steadily diminish the amount left in the house bank unless we turned off the fridge.
Conclusion, unless we plugged in or motored for a long time, which we CAN do on the Delta here, less and less is left in the house bank. It's a fairly common occurrence, as long as you either do the math or have a Link monitor.
But we KNEW that going in and, so, could adjust for it. If one wants to be totally self-sufficient, then solar (which we have but I didn't include above since it's just a small panel to offset the weekly discharge of the wet cell battery banks we have), or wind or both HAVE to be added, or a separate generator, or, as Captain. Ron says, "You just pull in and ask directions, Kitty" and sneak a little charge in while you're waiting!
The other conclusion is what we're all learning, and I say it again: there is simply no right way to do things electrically on our boats. It all depends on how you want to or need use your boat. Marina hopping, as mentioned above, will let you get away with a smaller house bank, although I still personally believe that a minimum of 400 ah in a house bank for those with refrigeration is the bare minimum to permit, as Mike V said, a frivolous weekend away with NO concerns about killing your batteries. A larger bank also extends the life of your bank because you draw down a smaller percentage of the total capacity.
We have written, as all the Mikes and others of you know, lots about this subject. And, it's just great that so many have read it - most, if not all of it!
Please also note that Jim's very happy with his batteryshack alternator. They come with BOTH internal and external regulation. Your boat, your choice. (Now, where have we heard that before?
Unfortunately, some of the direct links between subjects on electrical systems that I put into the earlier electrical system posts didn't transfer over from Infopop to this board, so it makes it hard to use some of the cross references that I previously posted on electrical systems. Sorry about that, but the information is all still there, and based on this topic, looks like more's comin' our way. Not a bad subject, and fun to discuss.
RECHARGING DEAD BATTERIES
Mike S, while I was looking for that steadily diminishing law of returns in Calder, I came across the answer to your other question about recharging dead batteries. I knew I'd seen it somewhere.
Page 47, second edition. "Is There Life After Death?"
Recommends equalizing the batteries on first charge. With your new Statpower True Charge Xantrex (or whatever they're calling them these days) 40, you should have an equalization setting. I recommend you do that to bring your batteries back. There's a whole page on the subject. I've posted a reference link on your earlier post to get here.
ENERGY BUDGETS, BATTERY USE & RECHARGING DEAD BATTERIES
Mike V's story was very well put. Was that heresy or hearsay? I don't know.
But follow this logic: Once you've got a good large house bank, and you've done all the wiring upgrades, and you've checked all your connections and you've got the monitoring system and you regularly check your distilled water levels, and you have a handle on everything, including your energy budget, and you either frivolously use or be miserly with your energy usage, what do you do next?
You learn about the steadily diminishing law of returns of how your engine driven alternator can replenish your batteries, regardless of whether it puts out 30 amps from the stock regulator, or 55 to 80 amps from a high powered new alternator with an external regulator.
We learned that this summer on our cruise (knew it already but saw it in action for the first time
).Page 46, Figure 2-13 of Calder's covers it well. Start out with full house bank, in our case 315 amp hours, from charging at our friend's dock. Spent two hours sailing, 20 nanoseconds motoring to our first anchorage. Stayed there two nights, less than three days. 315 less say 60 times 3 = 180 = 135 ah left. (Using fridge and lights "frivolously"). Motored 6 hours the next day. Input equals say 30 amps per hour, put back in 150. 150 + 135 = 285. (We get a good 30 amps input from our stock alternator because we still have our AutoMac.) Anchored out for three nights, turned off the fridge at night. 285 left less (3 x 30) = 195 left. Motored four hours = 30 x 4 = 120 + 195 = back to 315. On the hook for two more nights frivolously = 315 less 120 = 195. Sailed for a day, little motoring. 195 - 60 = 135.
This could go on and on until we plugged in again, and without motoring for long periods of time, would steadily diminish the amount left in the house bank unless we turned off the fridge.
Conclusion, unless we plugged in or motored for a long time, which we CAN do on the Delta here, less and less is left in the house bank. It's a fairly common occurrence, as long as you either do the math or have a Link monitor.
But we KNEW that going in and, so, could adjust for it. If one wants to be totally self-sufficient, then solar (which we have but I didn't include above since it's just a small panel to offset the weekly discharge of the wet cell battery banks we have), or wind or both HAVE to be added, or a separate generator, or, as Captain. Ron says, "You just pull in and ask directions, Kitty" and sneak a little charge in while you're waiting!
The other conclusion is what we're all learning, and I say it again: there is simply no right way to do things electrically on our boats. It all depends on how you want to or need use your boat. Marina hopping, as mentioned above, will let you get away with a smaller house bank, although I still personally believe that a minimum of 400 ah in a house bank for those with refrigeration is the bare minimum to permit, as Mike V said, a frivolous weekend away with NO concerns about killing your batteries. A larger bank also extends the life of your bank because you draw down a smaller percentage of the total capacity.
We have written, as all the Mikes and others of you know, lots about this subject. And, it's just great that so many have read it - most, if not all of it!
Please also note that Jim's very happy with his batteryshack alternator. They come with BOTH internal and external regulation. Your boat, your choice. (Now, where have we heard that before?
Unfortunately, some of the direct links between subjects on electrical systems that I put into the earlier electrical system posts didn't transfer over from Infopop to this board, so it makes it hard to use some of the cross references that I previously posted on electrical systems. Sorry about that, but the information is all still there, and based on this topic, looks like more's comin' our way. Not a bad subject, and fun to discuss.
RECHARGING DEAD BATTERIES
Mike S, while I was looking for that steadily diminishing law of returns in Calder, I came across the answer to your other question about recharging dead batteries. I knew I'd seen it somewhere.
Page 47, second edition. "Is There Life After Death?"
Recommends equalizing the batteries on first charge. With your new Statpower True Charge Xantrex (or whatever they're calling them these days) 40, you should have an equalization setting. I recommend you do that to bring your batteries back. There's a whole page on the subject. I've posted a reference link on your earlier post to get here.
) our mainsail at Sail Care, doing boom related fixes and haven't gotten around to it. The alternator is a direct match physically to the Motorola, it's a rebuilt inside a Delco case.