sailing to spain

[dilly]

i am thinking about sailing to spane next year and was think that a 4 man crew will up to 10 days nonstop sailing and was thinking to my self how meny hrs every 24 hrs must i run my engine to maintain my batteries any help would be good thanks ps i have 3 batteries 2 x110hrs 1x85 hrs

 

[Tranona]

Depends entirely on how much power you consume each day and how much your alternator (and any other power source such as solar or wind) produces. Do the sums of consumption and this will determine how many amps you will need to replace. Then you can work out your charging regime.

 

[dilly]

Don't know what what power I consume I run GPS fridge light nav gear auto pilot don't have sola or wind

 

[macd]

Don't know what what power I consume.

Then neither do we, I'm afraid.

I'd suggest you learn how to make a power inventory. In the first place this means going through the handbooks for all the bits of kit you'll be using (not forgetting the rating of nav light bulbs plus other lighting) and do some simple sums based on the output of your alternator. This is every bit as fundamental a part of your proposed voyage as tweaking sails and anything else you might do.

The simple option, simply waiting until your domestic batteries protest, won't do them any good in the long run.

 

[pelissima]

With a simple multimeter you or a friend familiar with electrics can easily measure each of your consumptions, multiply each by daily usage then add them to see your day need. A very rough guess would be a number around 80 Amps and I would expect you to run your alternator twice a day 2 hours each time. Remember this is only a guess to let you calculate your diesel inventory. Changing your lights to led, turning off fridge at night and doing turns at the helm total amps needed fall. Also a sola 50-80W is easily manageable around and is an expense well spent

 

[hartcjhart]

and keep this handy 112

 

[Chris Pink]

First: the unit is amp-hours (Ah), ie a device uses 1 Ah if it consumes 1 A for 1 hour. Confusing Amp-hours with Amps does just that - confuses the issue.

You don't mention laptop - a serious consumer of power but with the list above and depending on the usage of your fridge - the manufacturer will have typical daily figures - and saving on auto-pilot by having night watches I would say around 40-60Ah per day.

pelissima is right, the first and most significant saving is to fit LED lighting throughout. Go to eBay not the expensive 'boat' orientated types.

A solar panel of between 120W and 200W (depending on deck space) is the first thing to do.

If you do these things then the engine will hardly need to be run at all.

The main thing you need is a voltmeter and the knowledge of when your batteries need charging.

In my experience, 25 years, a power audit is a very vague thing but still worth doing if only to familiarise yourself with the units and relative consumptions. You will have small loads for a long time (LED lightsm nav lights), large loads for a short time (pumps), large loads for a long time (laptop, fridge) and it is good to have an idea of how these stack up.

 

[William_H]

I would suggest that OP fits (if he doesn't already have) an amp meter showing charge current. Plus a volt meter either multimeter or fitted volt meter. The volt meter will tell you when batteries are discharged and so need charging. Typically recharge when they fall to 12volts or slightly less. The amp meter will show how much current your alternator is putting into the batteries. This will diminish with charge time to a point where the charge current is not woirth the noise and fuel consumption. Typically might charge at 25 amps for some minutes then diminish to 15 amps. When and if it falls to 5 amps then stop engine and sail until batteries need more charge. As said probably around 1to 2 hr charging several times per day. These figures are very approximate. If you don't already have a smart charge controller on the alternator get one, this will give more current into batteries for shorter engine run time. (possibly half the engine run time)
I would second the installation of LED nav lights. Get the metering ASAP so you can get a feel for charging needs before you depart. good luck olewill

 

[dilly]

Thanks guy for your help I do have a volt meter and check that often I will take what's said onbord thanks