12 v electrics

[Homer 123]

I am going to live aboard a 45' boat with 12 v electrics and one starter battery and 2 leisure. How long each day will I need to run the engine to charge the batteries? It las low level led lighting and I'm not planning to have a tv but would like a radio- although I could just play the laptop and charge it in my van.

[Dave_P]

Do you have a fridge? That's the main power user.

[bottle]

I am going to live aboard a 45' boat with 12 v electrics and one starter battery and 2 leisure. How long each day will I need to run the engine to charge the batteries? It las low level led lighting and I'm not planning to have a tv but would like a radio- although I could just play the laptop and charge it in my van.

 

You will have to measure how long the piece of string is.

 

To be a little more serious, it will depend on your power usage and how large your alternator/charger is.

 

If you only use LEDs and the radio not very long but you will need to monitor the batteries

 

Volt meter and ampere meter is probably the cheapest but you will need to know how to interpret the readings correctly.

[Ally]

erm...if you can charge your lappy in the van, are you not doing that from 12v? Most lappy's have a compatible 12v charger available...though don't go for the very cheap ones which may not protect your lappy from spikes....so as long as you have some 12v sockets on the boat, you should be able to charge lappys, phones etc.

A lot of equipment is now available at 12v, tv's included....you could fit a 12v car stereo too. We are all 12v, though have 4 leisures totalling 500Ah. As to how long your leisures will last, that depends what size and condition they are and what your draw on them is.

[DeanS]

Hello:)

There are 2 ways to approach it.

 

Option 1: You buy a Smartgauge and look at it, before, during, and after cruising, and before, during and after battery charging (if you do it from a shorepower connection). Some enjoy this route. It allows you to know precisely if you are going to be able to read your book to the wonder of electric lights at the end of the day.

 

Option 2: You wing it. You go cruising, and hope it powered the batteries to get you through to day 2. On day 2 you go cruising, etc.

 

I'm with the option 2 group, but it's a very small group, and some say I should be in group 1. You can join either group, as they are free, and both very welcoming. If you do join group 2, dont tell group1 too loudly as it can get you branded as an idiot.

 

 

LOL.

Edited February 6, 2013 by DeanS

[Homer 123]

Lol thanks for your replies. I have a 12 v fridge in there. There are 2 normal sockets but don't suppose anything will happen if I plug them in? The hot water is on a calorifier. Te reason for charging in my van was to save power on the boat.

[dor]

Is the 12V fridge a Shoreline type or is it a 3-way 12V/230V/gas caravan type? If the former, depending on how old it is, it will use about 30AHr a day. This needs about 40AHr put back which will take a couple of hours or more even if you have a 90A alternator plus a longer charge once a week. (Led lights and radio are fairly negligible). This assumes your batteries are in good condition.

If the fridge is the caravan type it will kill your batteries in no time at all on 12V, but will be very economical on gas.

 

You really do need to get a voltmeter and ammeter fitted if not already and learn to understand what they mean. Lots of threads on this site discussing it, but also check out the smartgauge site for a learned discourse on battery management (doesn't mean you need the Smartgauge).

[trackman]

The risk of managing without a battery monitoring system of some effective type is more than just random loss of power for your lights etc.

Batteries are quickly damaged by being discharged deeply and start to lose capacity, before eventually failing. Given the cost of replacing a battery bank I think a Smartgauge or similar is worth the cost.

The advantage of the Smartgauge is that it's so easy to fit. One ground connection & 2 fused connections, one to the positive of each battery bank. That's it!

[smileypete]

Hello:)

There are 2 ways to approach it.

 

Option 1: You buy a Smartgauge and look at it, before, during, and after cruising, and before, during and after battery charging (if you do it from a shorepower connection). Some enjoy this route. It allows you to know precisely if you are going to be able to read your book to the wonder of electric lights at the end of the day.

 

Option 2: You wing it. You go cruising, and hope it powered the batteries to get you through to day 2. On day 2 you go cruising, etc.

 

I'm with the option 2 group, but it's a very small group, and some say I should be in group 1. You can join either group, as they are free, and both very welcoming. If you do join group 2, dont tell group1 too loudly as it can get you branded as an idiot.

 

Option 3: Fit an ammeter. Learn when it tells you your batts are charged enough, but don't stress if you only fully charge once a week. Then, fit a voltmeter. Learn when it tells you the batts have somewhere around enough charge, but don't stress about things being exact.

 

cheers, Pete.

~smpt~

[Homer 123]

There is an amp meter on the ignition panel do need another? Is that just for the starter battery?

 

There is an amp meter on the ignition panel do need another? Is that just for the starter battery?

[jake_crew]

There is an amp meter on the ignition panel do need another? Is that just for the starter battery?

You need to establish how the batteries are charged.

 

Are there two alternators ? If so, does one charge the domestic batts and the other charge the starter battery ?

 

Is there a "smart device" to control charging and 12v usage ?

 

Which circuit does the ammeter monitor. Do you see it swing into the + side just after starting the engine ?

 

We need more info to be able to assist further.

Edited February 6, 2013 by jake_crew

[Homer 123]

Ok, I've only just paid for the boat today and can't find out anymore until the cheques have cleared. It has one alternator and 2 leisure batteries, that's about I all I know but hoping to go up and spend the weekend on it weekend after next and find out what I can as well as getting used to it!

[dmr]

Unless you have unusually high or low usage or a bad charging system then a very good guess would be

Run engine for 2 hours every day

Once per week run engine for 8 hours

 

This also assumes that your alternator charges at a reasonably high voltage, some older ones do not.

Even with this charging your batteries will probably need replacing every year.

 

That 8 hour charge once er week is essential to get a periodic 100%, otherwise the btteries will "sulphate" and show a progressive loss of capacity.

An 8 hour run might fit in with your cruising habits, but if you are mostly static it might be an expensive pain in the arse! This is why lots of boats have generators.

As you only have two leisure batteries, and looking at the cost of diesel, it might just be worth forgetting the 8 hour run. You might need to replace your batteries twice a year but that would still work out cheaper.

A solar panel will help in the summer, and arrange to fit the new batteries just at the start of winter so you will get through the dark nights before they go too far downhill.

 

........Dave

 

 

 

 

what you are doing is unusual then it is

[Grace and Favour]

Hello:)<<>>

 

I'm with the option 2 group, but it's a very small group, and some say I should be in group 1. You can join either group, as they are free, and both very welcoming. If you do join group 2, dont tell group1 too loudly as it can get you branded as an idiot.

 

 

LOL.

 

Tut tut - - only an idiot would say that! ( )

[Dave_P]

Hello:)

There are 2 ways to approach it.

 

Option 1: You buy a Smartgauge and look at it, before, during, and after cruising, and before, during and after battery charging (if you do it from a shorepower connection). Some enjoy this route. It allows you to know precisely if you are going to be able to read your book to the wonder of electric lights at the end of the day.

 

Option 2: You wing it. You go cruising, and hope it powered the batteries to get you through to day 2. On day 2 you go cruising, etc.

 

I'm with the option 2 group, but it's a very small group, and some say I should be in group 1. You can join either group, as they are free, and both very welcoming. If you do join group 2, dont tell group1 too loudly as it can get you branded as an idiot.

 

 

LOL.

 

Group two rules!!!

[JDR]

I've got 220ah of leisure batteries and decided not to bother using a fridge. 30ah a day x 365=10950ah a year.To put that back into batteries (rough guess +30%)=14600ah. Dried milk-it's the way to go!

Edited February 8, 2013 by JDR

[Bod]

Option 1

 

May be expensive to buy, but no on going costs. Simple to fit.

 

Very easy to understand what the Smartgauge is telling you. Give a percentage of the battery's fullness, takes account of the batteries age and internal condition.

 

You will still have to charge the batteries, and top up the water, as required.

 

There are other systems, but they need a lot of understanding, as too set up, and information that you are being told.

 

Bod

 

PS

Yes, I have one.

Edited February 8, 2013 by Bod

[Homer 123]

OMG I've done it! House is sold. So all of a sudden this all becomes a reality. So what In the way Of elective can I run on a 12 volt? Slow cooker? Toaster? I have a 12 v kettle for my van that goes into a cigarette socket. I'd it worth having a docket put in?

[Bod]

www.roadpro.co.uk

 

Do 12v cooking equipment, and not that far from you in Daventry.

 

All the usual disclaimers etc. Just happen to have an old catalogue.

 

Bod

[Paul C]

OMG I've done it! House is sold. So all of a sudden this all becomes a reality. So what In the way Of elective can I run on a 12 volt? Slow cooker? Toaster? I have a 12 v kettle for my van that goes into a cigarette socket. I'd it worth having a docket put in?

 

You really need to understand how much current/power the devices you are thinking of plugging in, consume.

 

To keep it simple: heat water (kettle) and make toast using the gas cooker.

[Dovetail]

Turn off the 12V fridge if it can run of propane then go with that otherwise live without a fridge, plenty of cool places on boats to keep food fresh.

[Grace and Favour]

You really need to understand how much current/power the devices you are thinking of plugging in, consume.

 

To keep it simple: heat water (kettle) and make toast using the gas cooker.

 

Use gas hair curlers too!

[Arthur Brown]

Electricity is good for specialist things like HiFi sat-nav phones and computers, it's useful for lighting too.

 

Gas will do heating lighting and cooking, solid fuel is cheaper and will do heat and cooking well.

 

Get a solar panel or two, in the summer they will satisfy your needs, in the winter less so but still useful.

 

Most available alternators will need 2 hours to put much into a battery-especially the last few % of the rising state of charge as the alternators charge more slowly as the battery approaches full charge. Get a smartgauge.