1/2/Both switch bust?

[laika]

Perhaps you're still trimming wicks on paraffin lamps?

I've installed some notably un-cheap high cri leds in the saloon which are helpful when I'm working but my unquestionably favourite lighting source when I'm not working (and one of my favourite possessions) is one of these:
https://www.calibramarine.com/giftware-and-oil-lamps/petrolux/
If a technology is superior to others, I wouldn't discount it because the concept it old.

I do, however, have a VSR. And a a 1-2-Both switch which actually *isn't* a 1-2-Both switch but effectively wired as an on-off switch for the house batteries (because I have a VSR). I suspect mine is not the only boat where the wiring has been updated more than the labelling.

 

[richardabeattie]

Well when I switch to off everything goes off so I think I can live with the fact that all the other three switch positions turn everything on.

 

[VicS]

Well when I switch to off everything goes off so I think I can live with the fact that all the other three switch positions turn everything on.

I think the point may be that you are relying on a switch that is already probably defective. Maybe one day when you switch to OFF it won't switch anything off or perhaps when you switch to one of the ON positions it wont switch anything on.

Additionally as it stands you may not have the ability use the batteries separately or maybe one of them not at all. Quite which I dont think you know at present.

OTOH of course what you are experiencing may be due to some rather strange or unorthodox wiring which needs sorting out

 

[savageseadog]

My compass now has red "grain of rice" LEDs in it :encouragement:

I found red LED's didn't illuminate our Silva compasses very well.

 

[RupertW]

If you have two matching batteries, a very simple setup and don't mind messing around trying to remember which battery you should be charging, then 1-2-B switches work OK.

I have a single battery for starting my engine and 3 x 130ah batteries for domestics. Why would i want to select the single engine battery and run the whole boat from that ? I'm not alone, a great many cruising boats now have a lot of electrics, which require several batteries, the engine still only needs a single battery. Wiring such boats to a 1-2-B switch would be madness.

There you go again - although the 1-2-B switch is clearly wrong for the OP as he can't immediately diagnose the problem, it works absolutely fine even in a multi-battery setup like yours if the only person who ever touches is completely clued up on how 12v works. The only reason there are more complex solutions is that they are forgiving of ignorance so can be used easily for many more people.

 

[PaulRainbow]

There you go again - although the 1-2-B switch is clearly wrong for the OP as he can't immediately diagnose the problem, it works absolutely fine even in a multi-battery setup like yours if the only person who ever touches is completely clued up on how 12v works. The only reason there are more complex solutions is that they are forgiving of ignorance so can be used easily for many more people.

The reason i, and others, are still "going again" is because some people are a little hard of understanding. I think i am just a little bit "clued up on how 12v works", as i work with it all day, every day. Having a pair of on/off switches is hardly "complex", you turn them on when you arrive and off when you leave, in between there is no messing around changing settings or risking forgetting and leaving it on "both" and running the batteries down.

As for my boat, and other like it, why would any sane person want to run the whole boat from the engine battery, when there are 390ah of domestic batteries available ? Why would i want to start my engine with my domestic batteries ?

 

[laika]

I think I can live with the fact that all the other three switch positions turn everything on.

Whilst it might be a perfectly acceptable arrangement, per VicS's comment I think it would be wise to devote some time to make sure you understand *why* it works that way, especially if you normally have two batteries installed. If 12v isn't your area of expertise it would probably be worth a couple of beers to a friend or neighbour to look at it: doesn't need to take more than an hour. If you find your instruments failing on a long sail it's helpful to know what your options are. I could have saved myself some stress and time below with a multimeter on a channel crossing last year if I'd have understood a bit better how my VSR worked (and why I also need a link switch...)

 

[PaulRainbow]

I think the point may be that you are relying on a switch that is already probably defective. Maybe one day when you switch to OFF it won't switch anything off or perhaps when you switch to one of the ON positions it wont switch anything on.

Additionally as it stands you may not have the ability use the batteries separately or maybe one of them not at all. Quite which I dont think you know at present.

OTOH of course what you are experiencing may be due to some rather strange or unorthodox wiring which needs sorting out

I'd agree with all of that, it definitely needs looking into.

 

[PaulRainbow]

Please don't shoot me for having a 1/2/B.

This morning I brought just one battery to the boat to start the engine to move out to my berth. I put it into one of the two battery spaces. The cables to the empty space were left disconnected. All went well and everything worked - but it all continued to work irrespective of whether the switch was turned to 1 or 2 or both. Surely either position 1 or 2 should have switched everything off?

Check the switch with a multimeter Richard. The should only be continuity between the common terminal and terminal one on one setting, and common and terminal two on the other. There will be continuity between all three when set to both.

Also worth taking all of the cables off of the switch to see if anything is still powered up, it could be that you have circuits not isolated. It could even be that no circuits are isolated by the switch, it is used to determine where the alternator charge goes (as suggested by JD)

You need to be sure you are not using faulty equipment and that you understand how it should be working.

 

[richardabeattie]

Thanks Paul - I'll investigate as you suggest.

 

[RupertW]

The reason i, and others, are still "going again" is because some people are a little hard of understanding. I think i am just a little bit "clued up on how 12v works", as i work with it all day, every day. Having a pair of on/off switches is hardly "complex", you turn them on when you arrive and off when you leave, in between there is no messing around changing settings or risking forgetting and leaving it on "both" and running the batteries down.

As for my boat, and other like it, why would any sane person want to run the whole boat from the engine battery, when there are 390ah of domestic batteries available ? Why would i want to start my engine with my domestic batteries ?

This is where you seem to have a moment of blindness - anyone who has ever read a post of yours knows you are an expert in 12v but you are used to creating solutions for people who are not. If you are an owner who fully understands how 12v systems work and will be the only one touching it then 1-2-b is the simpler solution- don’t confuse simple controls for a simple system behind it. The 1-2-b is simple both ways but unforgiving of ignorance so understandably superseded for charter boats first then eventually for most others.

And on your question- if my engine starter battery failed eventually I would of course just switch to domestics to start it

 

[Tranona]

The 1-2-b is simple both ways but unforgiving of ignorance so understandably superseded for charter boats first then eventually for most others.

Not sure why you trot this statement out every time you try to justify why you persist using a flawed and out of date switching system. It is nothing to do with charters not understanding a flawed system. Individually switched circuits have been just about universal on new boats for many years, irrespective of whether the boats are used by charterers or not.

The reason is very simple. It is a superior way of managing your power supplies and reflects the changes in the way that boats are equipped and used. No different when 1,2 both switches came in - they were a response to the increase in electric equipment on boats that required increased battery capacity and additional circuits to the engine. As you admit, they are suboptimal as they are not idiot proof so a simple switching system where there is no chance of operator error has to be superior.

Really have difficulty in understanding why you think there have been no advances in the last 60 years or so.

 

[JumbleDuck]

Not sure why you trot this statement out every time you try to justify why you persist using a flawed and out of date switching system.

They aren't particularly flawed, just a different approach to the problem. Nor particularly out-of-date. After all, the two-separate-switches approach could have been used at any time, yet people chose to use a 1-2-Both switch instead, and it's arrogant to assume that their choice was stupid or ill-informed. There is no need to be snide at people who are happy to stick with one. For systems with two batteries of similar size, they are still a pretty good solution.

 

[rogerthebodger]

They aren't particularly flawed, just a different approach to the problem. Nor particularly out-of-date. After all, the two-separate-switches approach could have been used at any time, yet people chose to use a 1-2-Both switch instead, and it's arrogant to assume that their choice was stupid or ill-informed. There is no need to be snide at people who are happy to stick with one. For systems with two batteries of similar size, they are still a pretty good solution.

You mean like Brent who is adamant that his method is the only proper way and all other ways are flawed.

Paul and Tranona there are mainly ways to connect battery systems up each with their pros and cons.

I have a 3 battery setup with 2 off 1,2 b switches but no matter how my switches are set I con never discharge all my batteries except if the sun stops shining.

 

[solent clown]

Our hi tech set up has not one, but two, ancient bakelite twist to make cut off switches, one atop each battery connected with a thick U shape of flat bar. It looks very much like the set up is the same half century vintage as the boat itself. I know I should change it, but somehow I cannot bring myself to do so. The old domestic lightswitch that operates the bilge pump however, is not long for this boat.

 

[GHA]

Not sure why you trot this statement out every time you try to justify why you persist using a flawed and out of date switching system. It is nothing to do with charters not understanding a flawed system. Individually switched circuits have been just about universal on new boats for many years, irrespective of whether the boats are used by charterers or not.

The reason is very simple. It is a superior way of managing your power supplies and reflects the changes in the way that boats are equipped and used. No different when 1,2 both switches came in - they were a response to the increase in electric equipment on boats that required increased battery capacity and additional circuits to the engine. As you admit, they are suboptimal as they are not idiot proof so a simple switching system where there is no chance of operator error has to be superior.

Really have difficulty in understanding why you think there have been no advances in the last 60 years or so.

Whats the difference? 2 power sources, 1 power output- how is Rotary different from 2 singles? Not reliability, been through that one. Really cant see any difference other than how you visualize it.

 

[PaulRainbow]

Whats the difference? 2 power sources, 1 power output- how is Rotary different from 2 singles? Not reliability, been through that one. Really cant see any difference other than how you visualize it.

The difference is, with two battery banks and a single 1-2-B you cannot keep the two banks separate and have them powering the circuits they were intended for. IE, the engine battery powering engine circuits and the domestic bank powering domestic circuits, both on at the same time, both isolated from one another.

 

[PaulRainbow]

Our hi tech set up has not one, but two, ancient bakelite twist to make cut off switches, one atop each battery connected with a thick U shape of flat bar. It looks very much like the set up is the same half century vintage as the boat itself. I know I should change it, but somehow I cannot bring myself to do so. The old domestic lightswitch that operates the bilge pump however, is not long for this boat.

Sounds good, but you really should add a 3rd bakelite switch for emergency starting :encouragement:

 

[PaulRainbow]

You mean like Brent who is adamant that his method is the only proper way and all other ways are flawed.

Paul and Tranona there are mainly ways to connect battery systems up each with their pros and cons.

I have a 3 battery setup with 2 off 1,2 b switches but no matter how my switches are set I con never discharge all my batteries except if the sun stops shining.

Have we had this conversation before Roger

It's not the switch that's the issue, it's the system it's typically connected to. Your installation is not typical, it works and is safe, with built in backups, because of how you designed it. You clearly would not consider the typical system with a single starter battery, a large bank of domestic batteries and a single 1-2-B switch to be satisfactory, or you would not have installed what you have.

 

[VicS]

Whats the difference? 2 power sources, 1 power output- how is Rotary different from 2 singles? Not reliability, been through that one. Really cant see any difference other than how you visualize it.

There is no significant difference

BUT

What is suggested is two power sources, and two isolator switches supplying two separate circuits, namely the engine circuit and the domestic circuit.

One does the have to add a third "emergency combining" switch so that the circuits can be paralleled and operated from just one battery, or from both, if the need arises.

One also has to separate the alternator output from the starting and engine supervisory circuits and use a VSR, a low loss splitter , Sterling A2B charger or some other means of independently charging two batteries at the same time.

There are ways of simplifying such a set one. Eg by using a BEP VSR switch cluster or a Blue Sea dual circuit switch with battery combining. The latter is a neat way of simplifying the switching. reducing it to just one switch but retaining the advantages of the multiple switch arrangement.