Wiring diagram - circuits added for new stuff to my 1-2 both boat electrics - opinion/advice appreciated

[FairweatherDave]

 

[VicS]

The negative connection to the 1,2, both, off switch is not right surely?

 

[FairweatherDave]

The diagram show what I have added to my two battery system with a 1 2 Both switch. I use either battery as the start battery, and just alternate, the other battery then being for domestics. Theyt are equal size leisure batteries, (sealed lead acid). The circuits I have added are the ones shown, I have left off the normal stuff to the engine and switch panel.
So, over time I have added
1.solar
2. a diesel heater
3. a power socket
4 and 5. new circuits for VHF AIS Masthead lights
Everything works okay
My question is should things be improved in any way. I will add to that in a bit.....

 

[FairweatherDave]

The negative connection to the 1,2, both, off switch is not right surely?

I have a strong feeling you are right Vic! I didn't follow it closely where it went from battery one and suspect (now I think about it) that it just passes close to the back of the 1 2 Both and into the engine compartment.....
The 1 2 both works well so I think it is just me not thinking.

 

[FairweatherDave]

What is behind my question is I have read here lots of times people criticising other peoples wiring, saying that others have just added stuff incrementally to their boats in a bad disorganised way. And obviously I have slowly added stuff. So should I/ could I improve it (without doing a complete rewire and new switch panel)?

I should add that I can't see another way of adding the solar, and that I was advised to wire the diesel heater directly to the battery. And I also read it was a good idea to keep the VHF directly to the batteries for emergencies..... In an ideal world I would have the time and learn the skills to put in all new wiring and a switch panel and get rid of the 1 2 both, but since my system works do I need to change it ? (other than remove the negative between the batt one and 1 2 both switch in the wiring diagram )

 

[wingcommander]

The negative connection to the 1,2, both, off switch is not right surely?

Me thinks their would be a big bang if it was

 

[Poey50]

The diagram show what I have added to my two battery system with a 1 2 Both switch. I use either battery as the start battery, and just alternate, the other battery then being for domestics. Theyt are equal size leisure batteries, (sealed lead acid). The circuits I have added are the ones shown, I have left off the normal stuff to the engine and switch panel.
So, over time I have added
1.solar
2. a diesel heater
3. a power socket
4 and 5. new circuits for VHF AIS Masthead lights
Everything works okay
My question is should things be improved in any way. I will add to that in a bit.....

Not elegant, but that matters much less than whether it is safe. If you draw in the fuses (assuming there are some!) you can get an opinion on safety.

 

[FairweatherDave]

Not elegant, but that matters much less than whether it is safe. If you draw in the fuses (assuming there are some!) you can get an opinion on safety.

Thanks. I left out the fuses for simplicity for the diagram. Every circuit I have added has an inline fuse on the positive (supply). ( I am confident of my wire sizing and fuse rating). My only exception was for some reason I put the fuses for the solar on the negative returns to the batteries,and I need to change that. But I can redo the diagram is due course - it obviously needs one correction.....

But behind my questions about my wiring is a bit of a mystery. Both batteries were bought at the same time (March 22) and are same specification/identical. But battery two always seems to drop its voltage level a bit more than battery one. I monitored voltage closely through the summer and alternated which battery got decent charge when motoring. It never got too low but sometimes 12.2 while the other 12.5 volts. The solar had an issue and I ended up getting a new dual battery controller, but only at the end of the season. So I suspect a little voltage draw somewhere but not surewhere to look or how - nothing was ever left switched "on".

 

[emmalina]

Breaker to isolate your solar panels ! Switch of your batts and there is no control voltage on your solar controller.

 

[peteK]

All the negatives look too complex,wire them too a common busbar,engine block should be wired too negative.on batteries.

 

[William_H]

I think the basic arrangement is OK. What is important is to understand and remember how it all works and particularly that VHF and diesel heater are hard wired to one battery. This means no isolation switch for safety when leaving boat for this part of circuit. I would always prefer a starter battery and servicee battery with VSR to get engine charge. But you obviously do not want to start changing things around and are happy to manage 1,2,both switch.
Just do not get into the habit of starting and running on "both". Time will come when one battery dies and will not start engine. In both you will not know there is a problem until the other battery dies. Start on one then later the other at least occasionally to ensure each battery alone is up for engine starting.

 

[FairweatherDave]

All the negatives look too complex,wire them too a common busbar,engine block should be wired too negative.on batteries.

Thanks PeteK. I can see I could reduce the number of negative returns. It really illustrates how I added one project each year or so.

 

[Tranona]

Time to consider using those 2 batteries as a house bank and getting a separate engine start battery (simple 60-70Ah car battery) with a charge splitter such as a VSR from the engine alternator. Do away with the 1,2 both and switch each bank individually with a means of connecting the house bank to the engine in an emergency. Wire your solar just to the house bank. A distribution panel for the house bank for all domestic loads such as lights, nav lights, electronics, heater, power sockets USB. Much simpler, no need to switch from battery to battery, both banks are charged automatically from the alternator and the solar tops up the house bank,

 

[FairweatherDave]

I think the basic arrangement is OK. What is important is to understand and remember how it all works and particularly that VHF and diesel heater are hard wired to one battery. This means no isolation switch for safety when leaving boat for this part of circuit. I would always prefer a starter battery and servicee battery with VSR to get engine charge. But you obviously do not want to start changing things around and are happy to manage 1,2,both switch.
Just do not get into the habit of starting and running on "both". Time will come when one battery dies and will not start engine. In both you will not know there is a problem until the other battery dies. Start on one then later the other at least occasionally to ensure each battery alone is up for engine starting.

Great to get your input Ole Will! I'd like to get rid of the 1 2 both but I am used to how things function as they are. I do avoid the Both setting.

 

[FairweatherDave]

Time to consider using those 2 batteries as a house bank and getting a separate engine start battery (simple 60-70Ah car battery) with a charge splitter such as a VSR from the engine alternator. Do away with the 1,2 both and switch each bank individually with a means of connecting the house bank to the engine in an emergency. Wire your solar just to the house bank. A distribution panel for the house bank for all domestic loads such as lights, nav lights, electronics, heater, power sockets USB. Much simpler, no need to switch from battery to battery, both banks are charged automatically from the alternator and the solar tops up the house bank,

I agree that is what I would like to do, but so much easier to write it than for me to execute it - time and skill levels are against - particularly skill levels . But I aspire in that direction!

 

[PaulRainbow]

The engine should have a negative from the battery, nothing else. It should not be used as a busbar or conductor.

I'd tidy the negatives up with a busbar, as alreeady suggested.

I'd also get rid of the 1-2-B, as Tranona said. What could be easier than a switch for the engine and one for the domestic, with separate circuits ?

 

[Tranona]

I agree that is what I would like to do, but so much easier to write it than for me to execute it - time and skill levels are against - particularly skill levels . But I aspire in that direction!

Dare I say it - but if I can do it (and have done twice) it can't be difficult. Perhaps Paul will let you have a copy of his model wiring diagram and you will see how easy it is.

 

[FairweatherDave]

Dare I say it - but if I can do it (and have done twice) it can't be difficult. Perhaps Paul will let you have a copy of his model wiring diagram and you will see how easy it is.

Thanks Tranona, I've seen your very tidy switch panel piks and followed this issue from the sofa for ages so to speak,. I was just about to reply to Paul and say exactly your point..... I need a wiring diagram to follow and I have never found one .....so genuinely it would be great Paul if you could let me have a copy. Appreciate you have been championing this a long time.

And thanks for backing up the point about the negatives, busbar and the engine, that is certainly something I can do if I don't go all the way with the ditching the 1 2 Both.

 

[PaulRainbow]

Your wish is my command.

Skip the shunt if you don't have a battery monitor and obviously ignore one domestic battery.

 

[FairweatherDave]

Thanks very much Paul. I'll get back to the boat and see how I can do that.