PaulRainbow
Well-Known Member
Could you explain "the control it provides" and the advantages of the switching this, then that and how you protect yourself from the dangers of having the switch set to both please ?
1,2 Both Switch - When on Both do the 2 batteries even out on charge?
- Thread starter Jaguar 25
- Start date
Could you explain "the control it provides" and the advantages of the switching this, then that and how you protect yourself from the dangers of having the switch set to both please ?
PaulRainbow
Well-Known Member
Without any manual input from me, with my engine running the alternator charges the engine battery and the solar panels the domestic bank. All surplus alternator output is also fed to the domestic bank. Without the engine running the solar panels charge the domestic bank, with any surplus going to the engine battery.
pvb
Well-Known Member
But that's exactly what happens with countless thousands of boats which have a "smart" regulator and a VSR or diode splitter, and no harm seems to come of it.
PaulRainbow
Well-Known Member
Exactly. My little jump start pack is connected to a pair of heavy duty van batteries and a Transit alternator. Keeps nicely charged up without suffering any problems.
lpdsn
Well-Known Member
That goes against the grain when you consider that chargers are often configurable according to the size of the battery bank. Still, I guess if there's no evidence of harm.
PaulRainbow
Well-Known Member
I've never had a charger configured to the size of the battery bank. Types of battery, yes, not sizes though.
The Dogs Pollacks Brother
Well-Known Member
We had this on our last boat....2 batteries, a Bluesea OFF - ON - COMBINE switch and a split charge diode......no fuss what so ever. Turn up, turn on and away we go. Park up, turn off...job done, with the option to combine both if we wanted to.
lpdsn
Well-Known Member
The manual for my Sterling shorepower charger documents how to set the length of the equalisation charge according to the ratio of the size of the battery bank being charged and the output of the charger.
lw395
Well-Known Member
Thousands of small to medium yachts worked like this for decades with relatively few problems.
Turning the switch to 1 or 2 when you stopped the engine was just part of the action, like putting on the handbrake on your car.
Because most yachts were the same, people knew. And most yachts were running much less electrical stuff so it was not such a big deal anyway.
Now we have a whole range of more sophisticated solutions and people seem to have more problems.
You find lots of people don't understand what they have, and don't know its limitations or how to get the best out of it.
People use more Ah and they are more likely to have diverse charging sources, shore power, solar, generator.
A lot of people seem a bit shouty, telling everyone else what they should fit, without knowing what other people want from their boats.
For many people, sticking with what they have is a good option, and if changing things you have to look at cost, effort and benefits.
Maybe what some people need is a simple alarm when the switch is set to both and the engine isn't running? A £10 YAPP?
PaulRainbow
Well-Known Member
But that won't prevent the problems i mentioned earlier. Having it set to both has risks, at any time, engine running or not.
sailorman
Well-Known Member
So is mine via the duel sensing vsr, but i still from choice have a 12 both
pvb
Well-Known Member
Why? What does it actually do?
PaulRainbow
Well-Known Member
Think you will find that setting is absorption time not equalisation time, i'd forgotten about that one. The later Sterling chargers (Ultra) don't have this setting.
sailorman
Well-Known Member
gives me the option to use either bank for engine start. Originally she was wired up with 2 separate banks charged via a simple relay, the first season oi carried a jump lead, then added the 12 B & later when the relay went duff i added the duel sensing vsr
pvb
Well-Known Member
OK, so you presumably also have two separate on/off switches to isolate the battery banks?
sailorman
Well-Known Member
No, again originally only the neg could be isolated ( switched off ), well the switch is still there & used when i leave the boat.
why ( apart from the 12 B going duff) would i need 2 separate switches & a x over switch.
The system works for me & has done so most of the 18 yrs of ownership
lpdsn
Well-Known Member
Manual says equalisation (actually literally: equalization). I guess the modern ones can work it out themselves and adjust on the fly. Mine came with the boat and is about 10 - 12 years old.
ghostlymoron
Well-Known Member
A friend of mine is adamant that he wants manual control over his battery charging and couldn't see the point of automatic charging via a VSR. One day he rowed out to his boat found the 1-2-B had been left on B and both batteries were flat. He had to row ashore, take his car battery out, row back to boat, swap batteries, start engine to charge his boat batteries. It can happen to anyone and I don't want it to happen to me.
pvb
Well-Known Member
OK, so you use a single switch in the negative to isolate everything when you leave the boat.
shaunksb
Well-Known Member
I am just about to fit a 1-2-both switch on my Dufour.
It currently only has one battery bank that takes two batteries that are used for both starting and domestic as it was originally designed.
Double
So I'm adding a small 45ah starter in an adjacent well as an emergency start back up only with a dual sensing vsr.
I intend to use the (200ah) main bank to start and run the domestics as I do now but have the safety net of a separate starter battery ONLY as an emergency back up
So I will normally only ever switch the switch to 1 and go.
The alternator and 30w solar power will go straight to the main bank.
This means that I should have a back up starter battery that has a very easy life which I can check once or twice a season when I check for topping up etc.
Please feel free to play the Devils advocate...
__________________________
It currently only has one battery bank that takes two batteries that are used for both starting and domestic as it was originally designed.
Double
So I'm adding a small 45ah starter in an adjacent well as an emergency start back up only with a dual sensing vsr.
I intend to use the (200ah) main bank to start and run the domestics as I do now but have the safety net of a separate starter battery ONLY as an emergency back up
So I will normally only ever switch the switch to 1 and go.
The alternator and 30w solar power will go straight to the main bank.
This means that I should have a back up starter battery that has a very easy life which I can check once or twice a season when I check for topping up etc.
Please feel free to play the Devils advocate...
__________________________
