Wiring charger to battery

[SoSound]

Question on what wiring to run from the charger to the battery.

Currently, both positive and negative cables are the same color, which I'm not crazy about. The charger (ProMariner/ProTech) installation guidelines recommend 8 AWG for the length out and back that I have from charger to battery - are there any common practices or standards regarding what color to use for the charger to battery run? Do you make connections directly to the battery terminals or where the main cable from the battery connects to the battery switches? It's a Beneteau - one battery, two switches (one for house and one for motor).

Thanks,
Dave

 

[sailingdog]

Red for the hot wire, yellow for the ground. That way you're less likely to confuse the 12 VDC ground with a 120 VAC hot wire, which is usually black.

As for the gauge of the wire...depends on the distance from the charger to the connection point and the size of the charger.

You can make the connections to the posts where the main cable from the battery comes in.

Just curious, why do you have TWO SWITCHES for a single battery??? If the house side flattens the battery, how are you supposed to start the engine??? Most boats have TWO BATTERIES, one for the house bank, and another for use as a starting bank.

 

[SoSound]

That makes sense

I like the red for hot, and I like to be able to distinguish between the two different circuits (AC and DC), so red and yellow it is! The gauge I can handle, the installation guide tells me what to use for the length that I have to run.

On the two switch thing, it really does appear to me to be a Beneteau thing... Maybe someone who has a history with Beneteaus can shed some light as to why? I do plan to add another battery sometime soon. And maybe an emergency jumper too (although at this point, we don't typically use enough battery power to need either), but we're working on that as well - longer and more frequent trips...

Dave

 

[sailingdog]

Dave-

I prefer the BlueSea Dual Circuit Plus series of battery switches if you have two battery banks. It allows you to combine the house and starting banks in an emergency, but isolates the house loads from the starter.

Add an ACR or an echo charger to top off the starting battery, and have the charging systems charging the house bank, and you're good to go.

BTW, I highly recommend you use a good ratcheting crimper, as well as adhesive-lined, heatshrink crimp terminals, to make the connections.

 

[Randyonr3]

Dave
on your boat, as is mine, the cables should be black and brown but with time they start to look the same..
Its best to keep the same color going throughout the boat and just learn how the factory colors the wires. In this way, if any repair is done by anyone other than yourself, they are not confused by the mismatched wire color code.
What you can do, and I've found this to work well, is to purchase a couple rolls of electrical colored tape and color code the ends that you work on. Be it red & Black, red & Yellow or whatever. Also, If you ever plan to sell the boat, the serveyor will see that all origional wire color codes were kept with origional design.

 

[sailingdog]

Randy-

ABYC generally recommends hot 12 VDC lines use red insulation, and allow either black or yellow insulation for 12 VDC ground connections. I prefer to use yellow, since it can't be confused with a 120 VAC hot lead, which is normally black as well.

The list of ABYC recommended colors for DC wiring is located here.

 

[Randyonr3]

Maybe Beneteau hasnt read the ABYC recomendations, or maybe they got a good deal on black and brown wire... I only stated what the factory used and in the long run to keep with the same concept.

 

[sailingdog]

If you're going to be adding wiring to a boat... it generally makes sense to make it as easy to troubleshoot in the future... using just black and brown wiring is asking for trouble in the long run IMHO.

 

[Ross]

I used red + black - for all of my DC circuits and Jacketed white neutral black hot green ground on my AC circuits. I didn't use any unjacketed cable for my AC and twisted all of my pairs of DC wires. (It cancels the magnets flux on parallel DC wires.)

 

[brucecaptain]

One battery or two...

From experience, I'll bet you a lobster dinner at Sydney's Peace and Love on Jost Van Dyke that if you only have one battery, you will run it flat and find yourself stuck somewhere you don't want to be stuck! The sooner you add another; the better. Bruce

 

[repence@msn.com]

battery wiring

My 2-battery Beneteau 323 had two RED on-off switches (under the quarterberth) one for each of the two positive battery feeds, and a BLACK switch for the negative battery feed. I got a third RED switch when I added a third battery. Used red/black pos/neg wire. The 323 came with #6 charger wire, which was too big to fit in the Zantrex charger terminals without cutting away some of the strands. I wired the third charger wire straight to the new third battery terminal. The two factory-charger wires run way to the stern, across the boat, then back forward to get to where the terminate on the battery switches- that's about ten times longer than if they ran straight to the two original batteries. That's probably why my Xantrex remote panel for charger monitoring gives a different voltage reading though both house batteries are new 31's. I like these switches better then the 1-2-all-off switch.

 

[tweitz]

Guest --
As a fellow Beneteau 323 owner I am curious where you put the third battery. Also, I have noticed among 343 owners a lot of discussion that suggests that when you shut off the starting battery switch, a relay often keeps the circuit open, so that your load depletes both batteries instead of keeping the start battery in reserve. Did you find this to be the case?

 

[sailingdog]

Just curious as to why you have three battery switches? Ideally, your house bank should be two of the three batteries wired in parallel. Having two house batteries and a starting battery will complicate your charging setup as well as make the house bank less efficient, due to the Peukert factor.

You should also be able to consolidate some of the charging... by getting a single larger charger and either an echo charger or ACR-type battery combiner. This way, you can more efficiently use and charge your house bank and still keep your starting battery topped off.

My 2-battery Beneteau 323 had two RED on-off switches (under the quarterberth) one for each of the two positive battery feeds, and a BLACK switch for the negative battery feed. I got a third RED switch when I added a third battery. Used red/black pos/neg wire. The 323 came with #6 charger wire, which was too big to fit in the Zantrex charger terminals without cutting away some of the strands. I wired the third charger wire straight to the new third battery terminal. The two factory-charger wires run way to the stern, across the boat, then back forward to get to where the terminate on the battery switches- that's about ten times longer than if they ran straight to the two original batteries. That's probably why my Xantrex remote panel for charger monitoring gives a different voltage reading though both house batteries are new 31's. I like these switches better then the 1-2-all-off switch.

 

[Ron20324]

I was previously "Guest"; email if you'd like alot of detail: repence@msn.com. I I kept the 24 battery as the start battery, but moved it to under the quarterberth, into the cubby between the house battery (next to the drivershaft) and the starboard bulkhead. There are three outputs on the Xantrex charger. I found a Xantrex 40 for $150 and replaced the 20 that came on the boat. I have not experienced the depletion you mention.

 

[Ron20324]

Ideally, I have three switches for the three batteries. I can isolate or use any battery. This is an extension of the factory setup. I replaced the Xantrex 20 charger with a 40. Both of them have outputs for three batteries. The house batteries are not close to each other.The original battery test switch/meter was wired to the start battery. I moved the meter lead to the positive buss and can read any single battery just by turning on the associated red battery switch.

 

[SoSound]

Sailingdog,
I really do wish that someone with lots of Beneteau experience and electrical knowledge would jump in here and explain their philosophy.

I've seen lots of negative master switches on British sports and racing cars in the past, but they don't use multiple batteries (well, they might but it's only a temporary set up until the car is started and finished with the high amp draw from the starter motor). The Beneteau set up uses one switch to close or open the negative side of the circuit for all batteries. Each battery has its own switch for its positive lead. Turn any positive switch to the on position and that battery is added to the circuit, turn the positive switch off to remove any single battery from the circuit. Based on documentation that I've seen on their web site, even new Beneteaus might still use this arrangement.

I would like to add a second battery to my system, are their any First 285 owners who could suggest a good location and battery type for my second battery?

Dave

 

[sailingdog]

From my understanding of batteries and the problems associated with them. A house bank should be as large as possible. Doing this makes it far more efficient, since the larger the bank the better the Peukert factor is for the same load. The Peukert factor is basically why batteries have different amp-hour ratings at different amperage loads, and the higher the load relative to the battery bank size, the lower the effective rating.

For instance, if you have two 225 amp-hour batteries for the house side and use them independently, and have a 10 amp house load... you effectively have two banks that will yield about 100 amp-hours each before you to either switch to the second bank or start to recharge them. The load is effectively 4.4% of the bank capacity, for each battery.

Now, if you combine them, you'll have a single battery bank that is 450 amp-hours, and because it is larger, the load drops down to 2.2% of the bank capacity. Since the load is smaller relative to the bank size, the batteries will effectively last longer. This is why a battery will have a higher capacity at a 20-hour rating than it does a 5-hour rating... and the combined bank might give you 225 amp-hours, instead of the 200 amp-hours they would if used separately. Mind you, these numbers are not actually calculated, but chosen to illustrate the Peukert factor and how it plays into battery bank design.

It also makes your charging setup more effective, since you draining both batteries equally, and charging them together.... the plates and such will "wear" at the same rate. You can also simplify the electrical wiring setup, since the two batteries are effectively a single battery in terms of switches, fuses, the panel setup etc., meaning you can get away with a simpler charger, fewer switches, etc.