One of my projects for the winter is to install 2 additional house batteries. I dont have sufficient space around the engine and there is enough weight in cockpit locker so I thought of going to the space under the cabin bunks. The batteries are agm so they should be safe on their sides. My problem was the distance from the these batteries to the main batteries. I think its about 6 feet. I was thinking of using jumper cables with the croc clips removed and replaced with washer type connectors. I saw HF is selling 16 ft awg 6 cables for about 18 dollars. Should that be sufficient capacity
Connections to battery
- Thread starter ronald.hudson1
- Start date
wow...just....wow.....not safe on their sides.....not safe in any other realm......the project as a whole i mean.
When dealing with electrical items in a marine
environment you need all the help you can get. That means getting suitable MARINE GRADE cables. If you cannot get find ones ready made that will fit at a marine store then you will have to have some custom made at a marine electrical shop. Cables, even if they are solid copper. are no match for a marine environment. I replaced my original cables which were 10 feet long with custom marine grade cables. That was a while back and then it cost me over a hundred dollars but the peace of mind is well worth it.
environment you need all the help you can get. That means getting suitable MARINE GRADE cables. If you cannot get find ones ready made that will fit at a marine store then you will have to have some custom made at a marine electrical shop. Cables, even if they are solid copper. are no match for a marine environment. I replaced my original cables which were 10 feet long with custom marine grade cables. That was a while back and then it cost me over a hundred dollars but the peace of mind is well worth it.
Well,
Thank goodness for forums. It looks as if I'll have to go back to the drawing board. Thanks for putting me straight
Thank goodness for forums. It looks as if I'll have to go back to the drawing board. Thanks for putting me straight
My main concern would be the installation of the "washer type connectors". Cable connectors need to be solidly crimped on as if they are or get loose the connection will produce enough heat to melt the cover of the wires and start a fire. If the batteries are going to be 6 ft away from the switch that means they will have a 12 ft roundtrip run and depending on the load that you intend to power with them I would venture to say that 6 gauge might be inadequate. The type of wire you intend on using is not the best for the intended application. I gather your "main batteries" are not AGM and their recharging requirements might vary so they should not be mixed with the existing. If I would have tried to come up with a trick question I do not think I could have done any better than this. Do your homework and stay safe.
Ron, don't take shortcuts with your boat's electrical system. Take EXTRA measures to minimize corrosion (high resistance connections that generate heat with fire potential -- pun intended), as only marine grade (tinned copper) wiring / cabling should be used. Even then heat shrink tubing, taping, or electrical contact grease wouldn't hurt.
Another part of all this is proper installation of lock nuts / lock washers and torquing of all connectors ... connections can come loose eventually with all the bouncing and pounding of sailing. Once installed, a minimum of yearly inspections, reinsulating if necessary, a/o replacement should be done. Just say no to fires at sea !! ... or fires anytime.
And try to find / make your parallel battery closer to the existing battery, minimizing the distance that possibly a LARGE amount of energy (current) may travel...that holds true in ANY cable / wire run.
Another part of all this is proper installation of lock nuts / lock washers and torquing of all connectors ... connections can come loose eventually with all the bouncing and pounding of sailing. Once installed, a minimum of yearly inspections, reinsulating if necessary, a/o replacement should be done. Just say no to fires at sea !! ... or fires anytime.
And try to find / make your parallel battery closer to the existing battery, minimizing the distance that possibly a LARGE amount of energy (current) may travel...that holds true in ANY cable / wire run.
My existing batteries are No 27 agms. My current draws are low as all my lights are LED and my navigation system is tablet based. Of course there is a diesel starting but that is on a system that can be isolated so I didn't envision large draws on the extensions.
Google the awg chart (american wire gauge) and follow the instructions to find what wire size you need for how much current the batteries can potentially put out....that will make you safe on that part....then find a place to mount battery boxes and secure them before installing the batteries
This leaves a lot of questions:
#1 Why do you want more batteries? How many Ah's per day are you using? Are your batteries that are there now insufficient?
#2 What do you have for an alternator to charge AGM batteries? What battery charger, brand & model? Any other charge sources?
#3 How old are the other AGM's? What brand? What group size?
#4 While many AGM's can work on their sides very few are actually designed to be sitting on the side of the case, support wise. Best to check with the manufacturer to see how best to side mount them. Still they must also be firmly affixed to the vessel so they stay put.
#5 How are you monitoring state of charge of the battery bank? This goes back to; how do you know you need more batteries?
#6 Any wire interconnecting batteries should be all the same size or you can create imbalances between the batteries. Your boat is likely wired with 1/0 battery wire plus or minus one size. This is a LONG way from 6GA wire. Every battery cable on the boat should be sized to take starter loads. In an emergency you may need to combine batteries or cross connect via switches and that 6GA wire could over heat. AGM batteries also take tremendous charge current so even with the "light loads" 6GA wire is probably quite insufficient for the charging loads and will create voltage drop.
#7 Adding new AGM's to old is not the best idea. It is always best to start with an all new bank.
#8 Jumper cable from HFT is NOT a wise choice. If money is an issue don't buy AGM and insted buy less expensive flooded batteries and put the money into safe UL-1426 rated marine battery cable.
#9 When batteries are spread out how are you going to keep them in balance? Best to take the positive off one end of the bank and the negative off the other end. By connecting to just one end of the parallel bank the batteries closest to the + & - see the most use. Of course if using HFT cable and adding new batteries to old properly balancing the bank is small potatoes...
#10 Do you have a windlass?
#11 if the other two batteries are more than a few inches away then you will need over current protection at those batteries and the main batteries.
Ok
1) Not sure on the Ah per day. Im essentially a weekend sailor and the existing system is fine. I have a battery check on my main panel and over a weekend the indicator it may driop 1/2 volt.
2The engine is a Yanmar 20gm 2f and has the standard alternator on it. The battery charger is the Xantrex TC 20 + I have a solar panel which I use when moored.
3) I also use a hand held volt meter. The existing batteries are new this year on the additional ones would be the optima blue tops no 31. They are 2 years old. I keep all them charged year round. I also carry an emergency jump starter
4) The existing wiring is the origainl Beneteau 311 wiring. It is in good condition
5) Money is not an issue. The reason I had been looking at the the HFT idea was I was having trouble in finding the cabling for the battery. ( A problem when you do all your shopping on the internet and you dont know what you are looking for).
6) I don't have a windlass, TV,radar or power winches.
By the way thanks for going to so much trouble and putting me straight.
What I think I will do is keep the banks completely separate with the idea if I need to switch over I can do.
1) Not sure on the Ah per day. Im essentially a weekend sailor and the existing system is fine. I have a battery check on my main panel and over a weekend the indicator it may driop 1/2 volt.
2The engine is a Yanmar 20gm 2f and has the standard alternator on it. The battery charger is the Xantrex TC 20 + I have a solar panel which I use when moored.
3) I also use a hand held volt meter. The existing batteries are new this year on the additional ones would be the optima blue tops no 31. They are 2 years old. I keep all them charged year round. I also carry an emergency jump starter
4) The existing wiring is the origainl Beneteau 311 wiring. It is in good condition
5) Money is not an issue. The reason I had been looking at the the HFT idea was I was having trouble in finding the cabling for the battery. ( A problem when you do all your shopping on the internet and you dont know what you are looking for).
6) I don't have a windlass, TV,radar or power winches.
By the way thanks for going to so much trouble and putting me straight.
What I think I will do is keep the banks completely separate with the idea if I need to switch over I can do.
Ron, I bought a bunch of custom made cables from Mike at GenuineDealz.com. Wonderful guy to deal with, fast service, and quality products. Between Mike and Maine Sail (and this forum) I've learned a ton and greatly improved the electrical on my boat.
