PaulRainbow
Well-known member
Fit the VSR at the 1-2-B switch, connected to the two battery terminals.
Boat wiring - will this work?
- Thread starter Balbas
- Start date
Fit the VSR at the 1-2-B switch, connected to the two battery terminals.
superheat6k
Well-known member
So is the VSR a device to regarded as a potential, indeed likely, source of failure ?
PaulRainbow
Well-known member
Not in my experience. I find them to be extremely reliable.
William_H
Well-known member
The 1/2/b switch is based on the philosophy of 2 identical batteries. Typically a leisure battery with both engine start capabilities and some claim to deep cycle capacity. You use one and you save the other. Which is fine provided you alternate the battery used for engine start and remember to charge both on "both". The OP proposal is a variation on that philosophy just using individual switches. A VSR or diodes can be added to provide auto charge for both batteries.
The alternative might I say more modern philosophy is one of using a dedicated and specialised battery for engine start. ie a typical car battery so cheaper. The battery for domestic services then is chosen and designed for deep cycle and large capacity. It is not designed for engine start but will provide many support amps for engine start or indeed do it alone if necessary simply by it's usually larger size. Yes VSR is recommended or low drop diodes to automatically provide charge and isolation for the domestic battery but all this can be done manually with a switch which might double as the emergency jump start switch. So OP needs to decide on his battery duplication philosophy I certainly would go for specialised batteries. ol'will
The alternative might I say more modern philosophy is one of using a dedicated and specialised battery for engine start. ie a typical car battery so cheaper. The battery for domestic services then is chosen and designed for deep cycle and large capacity. It is not designed for engine start but will provide many support amps for engine start or indeed do it alone if necessary simply by it's usually larger size. Yes VSR is recommended or low drop diodes to automatically provide charge and isolation for the domestic battery but all this can be done manually with a switch which might double as the emergency jump start switch. So OP needs to decide on his battery duplication philosophy I certainly would go for specialised batteries. ol'will
Baggywrinkle
Well-known member
On thing about the Victron Cyrix battery combiner (VSR) that I like is that it can provide a 30s battery combine for emergency engine starting from both house and starter battery.
You can wire up a remote start-assist button (mine is next to the engine panel), if your starter battery is flat (and not faulty) the Cyrix will close for 30s and during this time, the house and starter batteries will be paralleled up for engine cranking - after 30s the Cyrix disconnects them both again.
You can wire up a remote start-assist button (mine is next to the engine panel), if your starter battery is flat (and not faulty) the Cyrix will close for 30s and during this time, the house and starter batteries will be paralleled up for engine cranking - after 30s the Cyrix disconnects them both again.
Nigelb
Member
PaulRainbow
Well-known member
As far as the batteries, switching and charging go, that's the same as what i posted at the beginning of the thread.
Balbas
New member
Right, thanks all for the help and suggestions. Having slept on it my plan is:-
Use as much of the existing componentry (cable, 1-B-2 switch etc) as possible but strip out the connection twixt engine start and domestic circuits. Plus clean every terminal and check every connection and wire for continuity. I have approx 3m of earth cable kicking around which should be good to run the earth from the engine to the engine battery, so that's 1 thing taken care of.
I will however add a VSR.
The reason I'm doing this is a) cost - I need a new sail! I could easily spend £400 or more on cabling and charging components and that would buy me a new mizzen.
and
b) I want to get this sorted lickety split so I can get back out on the water with the family.
In the 'off season' I will then do a proper re-wire.
I don't suppose one of you kind fellows would have a wiring diagram knocking about showing a circuit using the 1-B-2 switch and a VSR?
Thanks for all of your help, it has aided me in crystalising my thoughts.
Use as much of the existing componentry (cable, 1-B-2 switch etc) as possible but strip out the connection twixt engine start and domestic circuits. Plus clean every terminal and check every connection and wire for continuity. I have approx 3m of earth cable kicking around which should be good to run the earth from the engine to the engine battery, so that's 1 thing taken care of.
I will however add a VSR.
The reason I'm doing this is a) cost - I need a new sail! I could easily spend £400 or more on cabling and charging components and that would buy me a new mizzen.
and
b) I want to get this sorted lickety split so I can get back out on the water with the family.
In the 'off season' I will then do a proper re-wire.
I don't suppose one of you kind fellows would have a wiring diagram knocking about showing a circuit using the 1-B-2 switch and a VSR?
Thanks for all of your help, it has aided me in crystalising my thoughts.
PaulRainbow
Well-known member
Let me see .........
Attachments
Balbas
New member
Thanks. Interestingly, that would connect my engine battery to the domestic circuit - as I currently have it set up.
RupertW
Well-known member
That’s what it looks like to me too which can’t be what’s intended.
Balbas
New member
Must be - thinking about it, there is no other way to wire it through the 1-B-2 switch unless you also include an isolator.
PaulRainbow
Well-known member
RichardS
N/A
Surely it would only connect the engine battery to the domestic circuit if the 1B2 switch was able to be switched to allow it to do so?
Richard
Balbas
New member
Don't worry chaps, I was just being a bit simple. Its all clear in my head now.
Balbas
New member
Right, last question I promise.
I was going to go for some 50mm tinned core earth wire. But I think that might be overkill. Would 35mm be more appropriate? The longest cable run will be approx 3m and it's a 1500cc 4cylinder diesel.
Thanks.
I was going to go for some 50mm tinned core earth wire. But I think that might be overkill. Would 35mm be more appropriate? The longest cable run will be approx 3m and it's a 1500cc 4cylinder diesel.
Thanks.
PaulRainbow
Well-known member
Balbas
New member
Cool, thanks. In with case where is the best place to get cable and accessories from?
:encouragement: thanks.
PaulRainbow
Well-known member
You can shop around for 35mm tinned cable, 12v Planet charge £10.64
Unless the cables are in an especially damp area, there is no great need for tinned cables. You could shop around for some hi-flex welding cable, which is perfectly OK to use.
For the cable ends you will need some crimp on lugs and a decent crimper, ideally hydraulic. If you don't have one, you might be able to cut the cables to length and get you marina/boatyard to crimp the ends on for you. You should also heat shrink the ends of the cable, and the straight section of the lug.
Balbas
New member
A quick rummage around the garage has turned up 2 lengths (1 x 3.4m and 1 x 1.7m) of what looks to be tinned battery cable of approx 35mm. I've got crimp ends, a hydraulic crimper, a VSR and a new negative post on order.
It's not the full re-wire I wanted to do, but as I'm positive (groan...) that the issue is on the earth side of the circuit, it'll do for now. The 1-B-2 switch will live on for the time being, but if I wire the VSR up and ensure that I switch to domestic as soon as I've started up each time, I should be fine.
It's not the full re-wire I wanted to do, but as I'm positive (groan...) that the issue is on the earth side of the circuit, it'll do for now. The 1-B-2 switch will live on for the time being, but if I wire the VSR up and ensure that I switch to domestic as soon as I've started up each time, I should be fine.
