1-2-both switch! is it still required!

[PaulRainbow]

Rude and facetious ? Who's being that ?

Sorry Paul ... forgot it was you !!

I do read and I take OP's question / basis as the foundation for replies. Unlike some - yourself included.

From post #1

"For my upgrade, I just want to use the starter battery for starting the engine only and my house battery only for boat electrics."

Too often threads divert away from the core of OP's ...

My premis was to ask if it was really necessary to rip out and change for OP's boat ... plus I had also stated clearly that I now have two boats with the 'opposing' systems ...

Indeed, when people don't answer the OP is the most common cause, see above. Not forgetting, the OPs 1-2-B is knackered very old.

 

[PaulRainbow]

Everybody looks at these issues from their own perspective. There is no right or wrong. We used a 1,2, both switch for many years and we're quite happy with the set up. We didn't forget to switch it. We never flattened the engine battery. Somebody forgetful may deem a VSR an essential upgrade. Not being forgetful or distracted, I never saw the benefit of a piece of additional electrickery that could fail. VSRs are great for some people but not everybody. It's a shame people cannot see the perspective of others.
If we ever had a small simple boat again, I would not hesitate to keep a 1,2 both switch. If I wanted something more sophisticated, I would use a B2B such that the engine battery was given a perfect 3 stage charge. I don't like VSRs as they are an imperfect solution that takes no account of battery state of charge. They are just an electronic switch that does the same as a 1,2 both when switched. But that is just my personal opinion and shouldn't effect others decisions about how you wire YOUR boat

Agree with all of that, there is no one-size-fits-all. I design and fit on an individual basis. But the OP specifically wants separate circuits, not a 1-2-B

 

[B27]

The issue with 1 2 B switches is that generally there is only a single charging source so the need to switch to Both to charge both batteries.
....

The bigger issue is that yachts have now often got complicated, multiple charge sources, bigger demands.
House banks have got bigger.
Thrusters and windlasses are common on medium sized boats.
It's a long way from the days of many boat owners needing to take batteries home to charge properly.

I see a little irony in the fact that simple last century systems now work quite well with LED lights, nav on android tablets, and most significantly fridges which are much less power hungry.

There's still a core requirement to start the engine from one battery, another battery, or maybe both in parallel, but there are a whole lot of other requirements around charging and loads.

 

[B27]

From post #1

"For my upgrade, I just want to use the starter battery for starting the engine only and my house battery only for boat electrics."

Indeed, when people don't answer the OP is the most common cause, see above. Not forgetting, the OPs 1-2-B is knackered.

Where did he say it was knackered?
That would change things.

 

[Poey50]

Two other general points about switches. First, they seem to have a long life if well-made but not an infinite life as the contacts will eventually wear and you may lose the essential 'make-before-break' capability which could hurt alternator diodes. It's worth testing an old switch by moving between switch positions slowly and checking if there is any flickering of lights. If so, replace immediately.

I'm a fan of three-switch systems but its not a hill I'd choose to die on. For me, if there is something I might forget, I will do so eventually, so an automatic system suits my brain. If space is a problem for three switches but running separate engine and house circuits is desired then Bluesea do a single switch which allows those circuits to be kept parallel. It only has an emergency combine option however, unlike the additional emergency options offered by three switches but if space is your compromise then it's an option.

 

[seafox67]

Thank you all for your feedback. My question has been most definitely answered. Apologies, if I was not completely clear at the start as I did miss out a few bits. 1. My switch is very old and if I kept it would either need replacing or serviced. 2. The next future upgrade would be replacing the house battery with lithium (I think the Victron stuff can be adjusted for this).

Cheers

 

[geem]

The bigger issue is that yachts have now often got complicated, multiple charge sources, bigger demands.
House banks have got bigger.
Thrusters and windlasses are common on medium sized boats.
It's a long way from the days of many boat owners needing to take batteries home to charge properly.

I see a little irony in the fact that simple last century systems now work quite well with LED lights, nav on android tablets, and most significantly fridges which are much less power hungry.

There's still a core requirement to start the engine from one battery, another battery, or maybe both in parallel, but there are a whole lot of other requirements around charging and loads.

Our boat is complicated. We can charge via alternator, wind, hydrogenerator, solar and diesel genset. We can't directly connect the engine battery as the domestic battery is lithium. We also have a seperste generator start battery.
The engine batteries have their own solar and mppt. It's not switch on permanently. It's a tiny folding 40w panel that is deployed at anchor, periodically.
It will get swapped to a B2B in a couple of months when I install a second lithium battery.
The set up will be two B2Bs to charge the domestic bank when the engine is running. A B2B to charge the generator battery and a seperate B2B to charge the engine battery. All charging sources other than alternator, including 920w of solar go to the lithium domestic bank.

 

[PaulRainbow]

Where did he say it was knackered?
That would change things.

Apologies, my recollection of previous posts was slightly wrong, he said his switch "is very old! and worries me!"

But that changes nothing, he clearly states he wants separate circuits. Cannot do that with a 1-2-B!

 

[geem]

Thank you all for your feedback. My question has been most definitely answered. Apologies, if I was not completely clear at the start as I did miss out a few bits. 1. My switch is very old and if I kept it would either need replacing or serviced. 2. The next future upgrade would be replacing the house battery with lithium (I think the Victron stuff can be adjusted for this).

Cheers

So you don't want a VSR then. Not compatible with lithium.
Installing lithium is a whole new thread

 

[PaulRainbow]

So you don't want a VSR then. Not compatible with lithium.
Installing lithium is a whole new thread

The dreaded drip feed of info!

 

[seafox67]

So you don't want a VSR then. Not compatible with lithium.
Installing lithium is a whole new thread

No thank you to another thread! lol... The lithium mention is for a future a project in the next few years! The question for this thread was just about if the switch was required... Could I use a solution without a switch... would I be missing out on a important feature... and that has been answered very well! thank you all for your feedback

 

[Tranona]

Deleted.

 

[Tranona]

I had a marine electrician 'sort' the electrics on my 1999 Bavaria when we re-engined - he replaced most of the old cables and removed the old 1-2-B switches simplifying the system. Now have alternator connected to engine start batt with a Bluesea ACR to supply the domestic bank. No switches to worry about (other than main domestic bank isolate) and forget to close/open and both batteries are independent unless ACR senses current from alternator and is charging them. In the unlikely event the engine start battery fails I carry a pair of battery jump leads (never used). This system works well for me and removes old diode systems which drop the charge current. Main solar is connected just to domestic bank with a small (30W) panel to the engine battery (via regulators) for float charging when not on boat.

Don't think your Bavaria had a 1,2,B. Never seen one on a Bavaria as OE. That era boat would have had a split diode and an isolator in the common negative. Under the chart table on my 2001 37. Replaced it with a VSR switch cluster with individual switches and a parallel for emergencies (never used!)

 

[B27]

'very old and it worries me' does not very clearly state 'knackered'.
It may or may not still be working perfectly.

If it's not working properly, then get rid of it.

Some of these things either last forever or fail in the first 5 years.
A few years ago, there were some really poor battery isolators with the red keys, which didn't last.

If the OP has long term plans to add a Li battery, or change the house side to Li completely, then it might be a good idea to have that end goal in mind before changing anything now.

 

[PaulRainbow]

No thank you to another thread! lol... The lithium mention is for a future a project in the next few years! The question for this thread was just about if the switch was required... Could I use a solution without a switch... would I be missing out on a important feature... and that has been answered very well! thank you all for your feedback

If you intend to fit Lithium, you will need to change the switch and you will need something other than a VSR.

 

[jac]

Don't think your Bavaria had a 1,2,B. Never seen one on a Bavaria as OE. That era boat would have had a split diode and an isolator in the common negative. Under the chart table on my 2001 37. Replaced it with a VSR switch cluster with individual switches and a parallel for emergencies (never used!)

I have a 2002 Dufour. OE was proper isolators and a VSR. At some stage, someone had put in a 12B.

Never underestimate the stupidity of previous owners!

 

[PaulRainbow]

'very old and it worries me' does not very clearly state 'knackered'.
It may or may not still be working perfectly.

I already told you i misremembered what the OP said. [Inappropriate content deleted]

 

[Tranona]

If the OP has long term plans to add a Li battery, or change the house side to Li completely, then it might be a good idea to have that end goal in mind before changing anything now.

as others have already said, going to lithium is a whole new set of choices in systems and there is nothing in what is proposed that would limit the choices. The VSR would go, but everything else would be basically carryover, but maybe used in a different way.

 

[Ammonite]

.

I have a 2002 Dufour. OE was proper isolators and a VSR. At some stage, someone had put in a 12B.

Never underestimate the stupidity of previous owners!

The original owners of my 1999 Moody specified a 1-2-Both-Off switch as a chargeable extra from the factory instead of the standard VSR setup

 

[fisherman]

Trouble I had with a VSR on the camper: it kept clicking over as the panel kept the start battery topped up, but it disguised the fact that it was getting knackered, until it suddenly gave up one dull day.