Battery charging

single

single

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I have read loads of articles on here and now i'm even more confused what to get! Very basically i need to charge and maintain x1 80Ah engine start and x3 110Ah domestics. The engine has a 55Ah? alternator. I'm also thinking of adding solar very soon so what should i get in the way of charge control? Usual consumption. Lights,fridge,webasto 3500 heater, led tv, stereo etc
 
macd said:
How can it possibly known how many domestic batteries are installed? Isn't 3 x 110Ah in parallel (assuming wired correctly, which many won't be) the same as 1 x 330Ah to a regulator?
Click to expand...

Can you expand on the 'which many won't be' bit please?
 
LadyInBed said:
Are the 3 domestic wired in parallel or on different banks?
lf in parallel treat them as one battery and use a splitter to the other starter bank.
If they are all on different banks, you will need a lot of splitters!
Click to expand...

Currently the 3 domestics are in parallel but i can't understand why there are seperate leads going to each (+) from the xsplit charger box? It defeats the object.
 
single said:
Can you expand on the 'which many won't be' bit please?
Click to expand...

In a bank of three or more wired as seems simplest/most convenient, the batteries will each bear a different proportional of the combined load on them, to the detriment of the ones carrying the greatest burden.

See here: http://www.smartgauge.co.uk/batt_con.html

(If memory serves VicS provided the link years ago.)
 
single said:
I have read loads of articles on here and now i'm even more confused what to get! Very basically i need to charge and maintain x1 80Ah engine start and x3 110Ah domestics. The engine has a 55Ah? alternator. I'm also thinking of adding solar very soon so what should i get in the way of charge control? Usual consumption. Lights,fridge,webasto 3500 heater, led tv, stereo etc
Click to expand...

Get the Adverc, they'll help with which unit.

Get a VSR to share out the charge. Black box that does funny things to keep all of the batteries happy some of the time.

Look for the wiring circuit for getting the best out of your 3x110 batteries. Google about a bit, if I find it then it will appear somewhere on this thread. How do I know this?

A strong suggestion is to separate one of the 110Ah batteries and dedicate that to the fridge and get a 'limiter' [another, but different black box] that will not allow the fridge to run the battery flat. Also get a VSR that can cope with 3 banks of batteries
 
single said:
Currently the 3 domestics are in parallel but i can't understand why there are seperate leads going to each (+) from the xsplit charger box? It defeats the object.
Click to expand...

Because it's not wired correctly, that xsplit would be for three battery banks, not three batteries in parallel.

Brian
 
The first question for the OP is "What is the problem with the present system of engine alternator charging" IMHO this is still the basic and best charging system.
It can be used either with a 1,2,both switch to parallel all batteries for charge or can be done automatically by VSR or the xsplit charger box. (Which I am not famiar with)
You need a volt meter to monitor the voltage of the domestic batteries when running the fridge and not charging.
An amp meter will be useful to show just how much charge you are putting into the batteries. If you are running the engine to charge the batteries this will tell you when the batteries get more charged how the charge current falls till the charge is not worth the noise etc of engine run. There is no point changing anything unless you are dissatisfied with the present arrangement.
Now if you find that you are running the engine just to charge the batteries often then an Adverc Striling or similar charge controller can boost the charge current so reducing engine run times. Possibly cutting engine run times by half.
Then in addition to all this you may get the urge to go solar. This is expensive when you build sophisticated mounting for large panels. It does have tha dvantage of topping up the batteries when you are away from the boat. It is however difficult/ costly to get enough charge to not have to run the engine for charging. However any size is useful for keeping batteries happy when you are absent.
Re the 3 domestic batteries. They can be just paralleled and treated as one battery. However when they start to die it is necessary to separate them to isolate a bad battery. Isolation for ie fridge can be useful in husbanding electrical power also. If you want isolation of individual batteries you can fit a VSR to ensure recharge happens automatically when engine runs. good luck olewill
 
William_H said:
The first question for the OP is "What is the problem with the present system of engine alternator charging" IMHO this is still the basic and best charging system.
It can be used either with a 1,2,both switch to parallel all batteries for charge or can be done automatically by VSR or the xsplit charger box. (Which I am not famiar with)
You need a volt meter to monitor the voltage of the domestic batteries when running the fridge and not charging.
An amp meter will be useful to show just how much charge you are putting into the batteries. If you are running the engine to charge the batteries this will tell you when the batteries get more charged how the charge current falls till the charge is not worth the noise etc of engine run. There is no point changing anything unless you are dissatisfied with the present arrangement.
Now if you find that you are running the engine just to charge the batteries often then an Adverc Striling or similar charge controller can boost the charge current so reducing engine run times. Possibly cutting engine run times by half.
Then in addition to all this you may get the urge to go solar. This is expensive when you build sophisticated mounting for large panels. It does have tha dvantage of topping up the batteries when you are away from the boat. It is however difficult/ costly to get enough charge to not have to run the engine for charging. However any size is useful for keeping batteries happy when you are absent.
Re the 3 domestic batteries. They can be just paralleled and treated as one battery. However when they start to die it is necessary to separate them to isolate a bad battery. Isolation for ie fridge can be useful in husbanding electrical power also. If you want isolation of individual batteries you can fit a VSR to ensure recharge happens automatically when engine runs. good luck olewill
Click to expand...

I have only really noticed a problem keeping up with charging over the last few months while doing a re-fit. Every day i have been there with lights on and the heater running hence needing to run the engine for a few hours a day.Even running for 2/3 hrs won't charge them enough and volts keep dropping to about 11v which then shuts down the heating.I also noticed yesterday that the alternator charge light is ON when the engine isn't running! Could this be something to do with the problem? See pic.

View attachment 48677
 
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