If that location works I could use #6 according to the chart. How much heat would it add to the aft berth? We only use it for storage.
Battery Charger question...
- Thread starter SailFysh
- Start date
Awr, or arrggghhh........
Perhaps I misunderstand the difficulty it seems some have with this process.
1. Know the LOAD in amps.
2. Know the distance of the wire coming and going - like, add them up.
3. Look up on a table or a chart in the 3% voltage drop. Either ADD another x% or go to the next wire size up to take into account the drops through the connections. The charts all show a "range" of sizes, amps and distances, so there is not only "one" specific answer to any given installation, but rather choices. If one is near the uppermost range of a given wire size selection, go for the next sized wire.
4. Look up the fuse size for that size wire.
The linked BlueSea website has, conveniently, the wire and fuse sizing on the same downloadable PDF file.
Skimping on the wire size is simply foolish.
Rant over.
Perhaps I misunderstand the difficulty it seems some have with this process.
1. Know the LOAD in amps.
2. Know the distance of the wire coming and going - like, add them up.
3. Look up on a table or a chart in the 3% voltage drop. Either ADD another x% or go to the next wire size up to take into account the drops through the connections. The charts all show a "range" of sizes, amps and distances, so there is not only "one" specific answer to any given installation, but rather choices. If one is near the uppermost range of a given wire size selection, go for the next sized wire.
4. Look up the fuse size for that size wire.
The linked BlueSea website has, conveniently, the wire and fuse sizing on the same downloadable PDF file.
Skimping on the wire size is simply foolish.
Rant over.
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No need to rant Stu old buddy. I have done all you suggested. I have a complete and thorough understanding of the process (thanks to all of my friends here). I'm just trying to install it right the first time. On the 310 the location of the charger really is quite silly. You really can't see the face of the charger to read all of the info it shows while charging. Plus it is so far from the batteries. If I can find a better location it would Be a great improvement. Thanks.
I have done all you suggested. I have a complete and thorough understanding of the process (thanks to all of my friends here). I'm just trying to install it right the first time. On the 310 the location of the charger really is quite silly. You really can't see the face of the charger to read all of the info it shows while charging. Plus it is so far from the batteries. If I can find a better location it would Be a great improvement. Thanks.mr. jackson I am aware you mean well in your writing but the tone is often insulting, condescending and comes off as rude to other members. there is no need for this tone or behavior. if you really want to help other members please consider the tone of the writing before you press send. you post good links but your tone and demeanor are often hurtful. I don't believe you aware of how insulting you can appear to other members who know less than you. I think this is probably not your desire. please be nicer.Awr, or arrggghhh........
Perhaps I misunderstand the difficulty it seems some have with this process.
1. Know the LOAD in amps.
2. Know the distance of the wire coming and going - like, add them up.
3. Look up on a table or a chart in the 3% voltage drop. Either ADD another x% or go to the next wire size up to take into account the drops through the connections. The charts all show a "range" of sizes, amps and distances, so there is not only "one" specific answer to any given installation, but rather choices. If one is near the uppermost range of a given wire size selection, go for the next sized wire.
4. Look up the fuse size for that size wire.
The linked BlueSea website has, conveniently, the wire and fuse sizing on the same downloadable PDF file.
Skimping on the wire size is simply foolish.
Rant over.
sorry for the grammatical missteps I cant type well on this device.
I am so happy for you. Really. Sometimes it's challenging. That's why I prepared this following link years ago, to help people, because on forums like this we simply don't know what folks' backgrounds in real life are (I'm an engineer, and at first it was daunting, tooNo need to rant Stu old buddy.
): Electrical Systems 101 http://c34.org/bbs/index.php/topic,5977.0.html
http://c34.org/bbs/index.php/topic,5977.0.html
Maine Sail's excellent website and his forum on this board is also a tremendous resource.
And books are also a tremendous resource, because they usually have the tables and explanations - that's why the authors wrote the books.
Since you, like all of us with boats, are faced with space and location challenges, we either have to live with the location and increase the size of the materials connecting them, or change the location. In 1998, I spent quite some time figuring out the four different places I could locate my big heavy Freedom 15 inverter/charger. Back then they came with "pre-connected" lengths of the hefty 2/0 wires, which would have either defined the location or required extending those big wires which the manual said not to do. I contacted a number of other helpful C34 skippers and found one, who became a good friend, who was facing the exact same issue on the same boat with essentially the same I/C. We agreed on a certain location and both of our systems are working to this day. But this was done by email and Lists, in the old pre-internet/pre-forum days, which made finding this kind of information quite a bit harder than it is these days.
I don't know if you've discovered Jesse's blog, s/v Smitty. He has a C310 and is a wealth of information. He posts here regularly, so he shouldn't be hard to find. He may have "solved" your charger location and might be worth finding and reading before you do your final installation.
Good luck, again glad "you got it."
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Thanks Stu. I really admire you guys who freely offer your time and experience to us new guys. I hope I can one day.
Power = Current times Voltage ("P = I x E" is how I remember it). In this case it's the AC side you look at: 110 V and a max of 7 A for the 40A charger. About 800 watts max, normally less. Still a reasonable heat source.
I installed the remote display for my ProNautic. Real easy to run the cable to the nav station. You should also be sure to install the temperature sensor on the negative battery terminal.
Bulk charging is a lot longer than most folks assume it is, if the voltage sensed by the charge equipment is correct. For example in the article linked to below the 100Ah battery was charged from 65% DOD at 50A or a charge rate of 50% of Ah capacity .5C. With correct voltage sensing the bulk duration at .5C was 50 minutes. When you consider that to attain .5C on a 400Ah bank would require a charge source cable of producing 200A for 50 minutes you can see how fast this battery was charged, and bulk still lasted 50 minutes. Without correct voltage sensing bulk only lasted 30 minutes and the battery never attained the absorption target voltage in the 1 hour mark.
Here is a much more typical bulk duration, for most boats, with a flooded battery charged at .15C or 15% of rated Ah capacity from 50% DOD. If you are charging flooded batteries at around .15C, and bulk is not lasting this long, the answer is likely inaccurate voltage sensing or unhealthy batteries.
As can be seen with accurate voltage sensing the bulk duration lasted 1:46 minutes before the battery attained the CV limit of 14.6V.. This battery should be charged at 14.8V which would extend bulk out a bit longer.
Sadly far too few charger manufacturers add volt sense terminals to their product so the only option is to size the wires for minimal drop, if you want optimal charging performance and an unskewed CV duration.. Too often the sensed voltage is incorrect and the charge equipment enters the CV stage far too early. Once at CV the charger begins limiting current which can drastically slow the charging process especially when a charger is run off a small genset for a short duration or an alternator is run for a short duration (sailboats) and you want the maximum energy back into the bank in a short period of time.
Too much voltage drop also impacts the CV duration and any duration calculations the charger may be trying to make in order to get the battery as full as it can before transitioning to float. The duration at target voltage is critical to the health of the bank. In an ideal world no battery charger would transition to float until the battery was at 100% SOC but in the marine market we transition based on time & voltage not current & voltage. Making your charger see the most accurate voltage will allow the CV duration algorithms to work to their best potential.
For more on this I have an article on how voltage sensing impacts alternator charging but voltage sensing applies to all charge sources.
Alternators & Voltage Sensing
.
That seems long to me, but I've never really measured it. After running some battery sensor cables through the tubes under the head I'm thinking it would be pretty tough to replace the #4 charger cable I've got now with anything larger. Luckily I cheaped out and only got a 30A charger, so the #4 is ok.
But if I ever install the ACR I've got I could maybe swap out the 3 existing #4 cables for two #2s or #1s?
Yes I think the #2 wire for my 40 amp may be tough to get thru the conduit. I can verify the length is 21' of the old #10 I removed.
If you install an ACR at the same time you only need to run one positive and one negative, instead of two positives and one negative. That may make it easier. Maine Sail has some real good information on the ACR, as well as how to change the 1/2/Both switch so it selects the bank for usage, but charging always happens to both banks automatically.
I am putting the charger in the original location that Catalina did. There really is no closer well vented location. I wish there was so I could use smaller wire.
I am taking the advice of several who have mentioned using a ground terminal block for a cleaner install. It will really help the organization of wiring. I noticed terminal blocks are sized also.
BestBoatWire.com had 20, 50, and 100 amp. What size do I use with my setup?
40 amp promariner charger
60 amp fuse on charger + leads at battery.
Thanks
BestBoatWire.com had 20, 50, and 100 amp. What size do I use with my setup?
40 amp promariner charger
60 amp fuse on charger + leads at battery.
Thanks
I went with 3/8 bolts on a shunt for cables from the battery to a 250A 5/16 x 6 posts for the bigger ground cables (alternator, charger, engine,DC panel, ACR's) - small wires connect to either a 6 position fuse panel for 24x7 or are grounded at the DC panel.
Having lots of room for bigger cables will reduce the temptation of sneaker wires getting in after the shunt.
Having lots of room for bigger cables will reduce the temptation of sneaker wires getting in after the shunt.
Neal, congratulations! Two questions: are you strapping down the batteries, and is there a tray under them?
Also interesting that your seat is wood. Ours (2000) is fiberglass with a wooden cover/insert.