Caravan Battery Level

Submitted: Friday, Mar 21, 2014 at 00:35
ThreadID: 106817 Views:2575 Replies:12 FollowUps:31
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I have a relatively new caravan with 2x100ampr batteries on board. System is protected by a 40amp Electro unit. As with most new caravans most things require power to operate I can only achieve one overnight 24 hr stop which reduces battery level below 12 V. I run the 184l ,3 way fridge on gas when parked up. We use lights and water pump sparingly. I suspect that the thermo fan behind the Dometic fridge which is direct wired to the batteries operates continuously overnight and when travelling and may be draining the batteries. Has anyone experienced similar problem?

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Reply By: Motherhen - Friday, Mar 21, 2014 at 01:11

Friday, Mar 21, 2014 at 01:11
How are the batteries being charged Smithie? You may not be getting enough power into them.
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Reply By: BUSH CAMPER - Friday, Mar 21, 2014 at 08:44

Friday, Mar 21, 2014 at 08:44
when TV is not operating turn off aerial booster as this chews up power.
Also heard that if you have a new tug the alternator may not charge all batteries.
I have a 200 series cruiser and can't charge and run everything.
cruiser has 2 batteries under bonnet, I have another battery strapped in the back, connected to charging system, Anderson plug to van to charge 2 x 105 batteries and run the fridge while driving. Also run a 40 Lt engal in cruiser using the 220 volt plug.
This is a big ask for the alternator. Maybe some else can add to this.
Regards Hugh
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Follow Up By: HKB Electronics - Friday, Mar 21, 2014 at 08:55

Friday, Mar 21, 2014 at 08:55
Bush camper,

Do you run a booster diode, it would improve your charge rate but that is a lot of battery capacity you have connected.

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Follow Up By: BUSH CAMPER - Saturday, Mar 22, 2014 at 17:11

Saturday, Mar 22, 2014 at 17:11
No, where would this be fitted?
When camping I use a 120watt solar panel for the battery in back of cruiser and the van has a 135 watt solar panel.
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Follow Up By: HKB Electronics - Saturday, Mar 22, 2014 at 17:35

Saturday, Mar 22, 2014 at 17:35
What is the make and model of your car?

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Follow Up By: BUSH CAMPER - Saturday, Mar 22, 2014 at 20:59

Saturday, Mar 22, 2014 at 20:59
200 series landcruiser, GXL, built late 2102, Diesel V8
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Follow Up By: HKB Electronics - Saturday, Mar 22, 2014 at 21:56

Saturday, Mar 22, 2014 at 21:56
The 200 series is fitted with a low output alternator, charge voltages of 13.5V or lower are common with this model, fitting a booster diode will restore your vehicles charging voltages to close to those of a standard alternator improve your battery charging considerably.

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Reply By: HKB Electronics - Friday, Mar 21, 2014 at 08:56

Friday, Mar 21, 2014 at 08:56
smithie12

What is the make and model of your car?

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Reply By: Ross M - Friday, Mar 21, 2014 at 09:27

Friday, Mar 21, 2014 at 09:27
smithie12
Is the fridge 12v heater actually turning off when you put it on gas? that could explain the drain.

Or

The charge system isn't doing very much.
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Reply By: Dennis Ellery - Friday, Mar 21, 2014 at 12:35

Friday, Mar 21, 2014 at 12:35
You can’t guess the solution to your problem unless you know whether you are getting a good charge into your batteries. Using a clamp on ampmeter, measure your charge rate when the caravan batteries are low. With 2 x 100ah batteries at a low level, you will need 20 to 40 amps over 3 or 4 hours from your vehicle (depending on level of discharge).
If you are only charging off your motor vehicle and do not have a 40amp DC/DC charger in your caravan it’s likely that you are not putting enough power into your batteries to run things over night.
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Follow Up By: The Bantam - Friday, Mar 21, 2014 at 22:41

Friday, Mar 21, 2014 at 22:41
If there are two 100 amp hour batteries and they are half discharged.....it will require a 20 amp charge rate of at least 6 hours to achieve a full charge.

Problem is the charge rate decreases as the level of charge in the battery increases.....so even with an initial charge rate of 40amps...it may still take 8 to 10 hours..or more to achieve a full charge.
Because toward the end of the charge cycle tha charge current may be as low as 5 amps.

One of the consistently re-occuring reasons for batteries failing to charge is insufficient time allowed.

AND...no gismo, Dc to Dc charger or snake oil will change that situation much.

cheers
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Follow Up By: Dennis Ellery - Saturday, Mar 22, 2014 at 16:46

Saturday, Mar 22, 2014 at 16:46
No one suggests you can get a full charge in 3 or 4 hours with standard batteries – that’s being silly Bantam.
Many AGM's such as Lifeline and Optima can get up to 95% state of charge in 2 hours - I could go into the technical details but it would be a waste of time.
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Follow Up By: The Bantam - Saturday, Mar 22, 2014 at 17:15

Saturday, Mar 22, 2014 at 17:15
There are plenty of people that think they can charge a large battery in a couple of hours driving.....plenty of those people have batteries dying prematurely.

NOT many AGM...a certain few can be rapidly charged.

Certain AGMs have a very limited maximum initial charge rate...a particular popular Fullriver 100AH is limited to arround 20 amps maximum initial charge rate.

Yes I am aware of the claims that certain batteries claim to be able to charge very quickly.....AH yes...but then there is the detail..always the detail.

Have you ever charged an optima or a lifeline, from an unmodified car alternator, in a trailer,from a low state of charge to a proven 95% charge in two hours.
If so..how did you measure it.


the fact remains that for most people charging a pair of 100Ah batteries, from a low state of charge, in a trailer, from the standard or even voltage bumpeded alternator will take in the reigon of 6 to 10 highway driving hours.....if all is going their way.

cheers
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Follow Up By: Dennis Ellery - Saturday, Mar 22, 2014 at 18:17

Saturday, Mar 22, 2014 at 18:17
You don’t need to fully charge a good deep cycle battery each time – a full charge every 8 or 10 times is OK.
That’s according to the manufactures specs for my AGM – I stick to manufacturer’s specs rather than e-opinons of unknown credibility.
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Follow Up By: The Bantam - Saturday, Mar 22, 2014 at 23:59

Saturday, Mar 22, 2014 at 23:59
Its an unavoidable reality that if you fail to put in more charge than you take out, day after day, the battery will soon not last the night in the short term and in the long term will fail...regardless of battery type or capacity.

The single biggest reason for battery disapointment, is failing to provide sufficient charge time.

cheers
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Follow Up By: Dennis Ellery - Sunday, Mar 23, 2014 at 10:39

Sunday, Mar 23, 2014 at 10:39
Bantam
To avoid repeating myself, see my comments further down the post.
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Reply By: SDG - Friday, Mar 21, 2014 at 15:31

Friday, Mar 21, 2014 at 15:31
Next time your at home, fully charge your batteries with a 240v battery charger directly to batteries. When charged turn on what you would use, as you would if camping. See how long you get. If still only 24hrs, you know if it is at the van end. Something using more than it should. If more, at least you will know it has something to do with your charging.

What globes do you have in van? Halogen I have been told, use a bit.
As an experiment, turn the fan off. Disconnect, whatever. Put a switch in it.
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Reply By: Member - Triton42 - Friday, Mar 21, 2014 at 16:09

Friday, Mar 21, 2014 at 16:09
One answer could be to install a solar panel.

I can camp for as long as I like and don't have to worry about running the batteries down.

Of course I run the fridge on gas when camping.
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Reply By: guy007 - Friday, Mar 21, 2014 at 20:18

Friday, Mar 21, 2014 at 20:18
Hi Smithie,
What sort of batteries are your 100amp hour ones in the caravan?. My Van came supplied with 2x 100 amph CALCUIM deep cycle batteries. These need upwards of 15 volts to properly charge them which is why I run a redarc DC 40 amp charger in the caravan set to calcium mode to keep them charged. Likewise with the solar when parked.
Recently at Phillip Island Classic races we had no 240 volt power and 2.5 days cloudy weather. Batteries were fine as we had everything set to charge at 14.5 volts.
Batteries are 5 years old.
regards
Guy
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Follow Up By: Dennis Ellery - Friday, Mar 21, 2014 at 21:50

Friday, Mar 21, 2014 at 21:50
That’s the way to go.
A DC/DC charger in the caravan, compensating for the volt drop between the vehicles, is the only way to get a decent charge into the van’s battery.
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Follow Up By: The Bantam - Friday, Mar 21, 2014 at 22:46

Friday, Mar 21, 2014 at 22:46
Here we go again.....DC to DC chargers are NOT the only solution.

Correctly sized wiring and the proper charge voltage will do the job..and in some situations better.

cheers
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Follow Up By: Dennis Ellery - Saturday, Mar 22, 2014 at 16:39

Saturday, Mar 22, 2014 at 16:39
It’s impossible not to have voltdrop between the vehicles alternator and van battery - no matter how large the wiring.
My alternator will put out about 13.6 volts and I set the DC/DC charger output to about 14.5 volts.
This is a much better charging effect on my batteries using 14.5 volts as opposed to something less than 13.6V
In most cases the DC/DC charger is the most practical solution.
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Follow Up By: The Bantam - Saturday, Mar 22, 2014 at 17:26

Saturday, Mar 22, 2014 at 17:26
It is impossble to have current flowing in any wire and not have voltage drop.

That does not make it an unavoidable problem for charging batteries.

Heavy enough wiring...and it does not need to be rediculously heavy will overcome any problems with voltage drop.



YOUR problem is that your alternator has a poor voltage output to start with.....all you are doing, is using your DC to DC charger to increase the voltage.

Installing a 14.2 volt alternator or fitting a diode fuse along with adequate wiring would in many cases result in more rapid charge than your DC to DC charger.

Don't claim that a DC to Dc charger is the only way to go because it just is not true.

cheers
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Follow Up By: Dennis Ellery - Saturday, Mar 22, 2014 at 18:30

Saturday, Mar 22, 2014 at 18:30
Mine is not an uncommon voltage – it’s in a 2008 Toyota.
Vehicle manufactures have it at that voltage level for reasons I won’t go into.
It silly to say change your alternator to a higher voltage, when you can do a better job with a DC/DC charger and also keep the voltage for the battery under the bonnet at the correct level.
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Follow Up By: HKB Electronics - Saturday, Mar 22, 2014 at 20:38

Saturday, Mar 22, 2014 at 20:38
The lower voltages Toyota now run have nothing to do with maintaining the correct voltage levels for the battery, they have lowered the voltage levels to meet overseas emission requirements and to improve fuel economy figures. This has resulted in a significant increase in warranty claims for cranking batteries due to the poor charging voltage.

Toyota have slightly increased the charging voltage in the latest Prado's for instance to try and overcome the high rate of battery failures.

The dealers have are also suggesting occasional charging with a battery charger too.

Increasing the voltage back to normals levels by use of a booster diode is both beneficial for both the cranking and auxiliary batteries.

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Follow Up By: Dennis Ellery - Saturday, Mar 22, 2014 at 22:08

Saturday, Mar 22, 2014 at 22:08
I would have thought that with a name like HKB Electronics you would appreciate the fact that the voltage level for charging a battery varies with temperature.
I have seen studies by Exide that show under bonnet temperatures for sedans around 70 degrees.
I have measured my V8 diesel around 80 degrees – the battery electrolyte reaches the mid 60’s.
Bantam’s suggested 14.2 volts for under bonnet batteries will shorten their life – it’s well published engineering data. Toyota's voltage for my vehicle of 13.9 volt for a cold motor and 13.6 volt when hot, is correct and I wouldn’t be changing it to a higher voltage on an a layman’s recommendation.

You don’t happen to sell these diodes do you? – maybe you could flog a few to Bantam.
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Follow Up By: The Bantam - Sunday, Mar 23, 2014 at 00:37

Sunday, Mar 23, 2014 at 00:37
Again Dennis brings up esoteric half truths.

Any temperature over 25C will reduce lead acid battery life..regardless of charge voltage.

On the one hand you sprout the rapid charge capacity of some AGM ( to achieve those very fast charge rates quite high voltages are required) on the other hand you espouse lower charging voltages.

On the one hand you claim that you cant fully charge a battery on the lower voltages and that a dc to dc charger is required and on the other hand you claim that underbonnet temperatures require lower voltages

Ya cant have it both ways.

When we mostly ran screw top batteries almost without exception the charging voltage of a car alternaotor was 13.8 volts.....this was chosen because it is the best compromise between expedient charging and fluid loss....it remains the prefeered float charge voltage for almost all lead acid family batteries.

When we started to see vehicles come from the factory with sealed maintenence free batteries the alternator voltages stepped up .6 volts of a volt to in most cases 14.2 volts.
This is because the calcium in the plates, altered electrtolite chemistry and gas recombination is sealed batteries allows ( some argue requires) the additional voltage.

WHY would pretty well all manufacturers increase the alternator voltage from 13.8 to 14.2 volts when fitting sealed batteries if it was not a good idea.

People have been geting reasonable life (3 to 5 years) out of batteries under bonnet for decades with those set charge voltages.

While there may be an in theory case that higher charge voltages with high underbonnet temps may reduce battery life....in reality the case is not proven reasonable.
High under bonnet temperatures will reduce the life of the battery regardless of the .6 volt difference.

There IS however a case and it is well known that some of the very recent, tree hugging, low alternator voltage cars are expereincing a chronic failure to sufficiently charge the factory fitted cranking battery and reduced battery life because of it.

While battery manufacturers have been publishing temperature compensated charge curves and battery life V temperature data for decades.
In general it is not common to vary charge voltage unless the charge process is being pushed near limits.

In most vehicles the alterenators and batteries are sized such that the alternator is incapable of pushing the battery near limits in normal use.

There is also the argument that even normal non ecu controlled alternators are at least to some degree temperature compensated.

as I have posted before..don't bother about the esoteric and the obscure...get back to the simple basis.

sure higher temperatures may reduce battery life...but chronic under charge will do as much if not more damage....and that is a certanty.

cheers
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Follow Up By: HKB Electronics - Sunday, Mar 23, 2014 at 09:48

Sunday, Mar 23, 2014 at 09:48
Dennis I suggest that you actual do some research before commenting, alternators are temperature compensated, the booster diode simply restores the charge voltages to same levels that have been used to charge lead acid batteries since cars were first fitted with batteries ie 14.4V@22C or there abouts. Why this voltage because that is what was determined to be the best voltage to charge a lead acid battery some 100 years ago and it hasn't changed since!

Your DCDC charger will change at around 14.4V CTEK and 14.5V Redarc under the same conditions ie they simulate what the alternator does and that is what it was designed to be a pseudo alternator.

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Follow Up By: Dennis Ellery - Sunday, Mar 23, 2014 at 10:37

Sunday, Mar 23, 2014 at 10:37
HKB
My vehicle has a temperature compensated alternator – starts at 13.9v and after it heats up, drops back to 13.6V. Toyota engineers do that to prolong the life of the battery in a very hot environment.
My DC/DC charger charges a battery in a cool environment. Totally different voltages required.
But I understand the need to flog your voltage booster, and this will make these observations irksome.

Bantam
A lot of under bonnet batteries live their life undercharged.
In my case the 4WD is not used more than once a week when I’m in town.
I need to trickle charge it when it’s sitting idle to gain maximum life from my batteries.
When camping, the AGM in the caravan is only fully charged once a week - it’s not practical to get a 100% each day - the other 6 days possibly gets to around 80%.
According to my manufacturers specs this is a good charging regime.
I can’t go into the rest of your comments - they shoot off in all directions.
I would take for ages and would be a waste of time.
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Follow Up By: HKB Electronics - Sunday, Mar 23, 2014 at 10:56

Sunday, Mar 23, 2014 at 10:56
Dennis your just plain wrong, as I already wrote Toyota dropped the voltages to meet pollution requirements at the cost of battery life, if you don't wish to believe me I suggest you talk to a Toyota service technician.

There are many other makes out there still running standard charging voltages as they have been able to meet the pollution requirements without altering charging levels.

Your vehicle has a high compensation type alternator, initially it will start charging at a reasonable voltage to put some charge in the battery but as soon as the temperature under bonnet nears the temperature at which vehicle emissions are tested, it will reduce the charging voltage way below what is required to maintain the correct temperature compensation.

To shot your claims down your argument in flames, and as I have already mentioned Toyota in their latest models have raised the charging voltages somewhat in an attempt to lower battery warranty claims, so much for the lower voltages being good for the battery!

I suggest you do some reading on reducing charging voltages as a way of meeting vehicle anti pollution standards. This information has been around for many years.



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Follow Up By: HKB Electronics - Sunday, Mar 23, 2014 at 11:07

Sunday, Mar 23, 2014 at 11:07
Dennis, buy the way a further naoil in the coffin for your argument, if you do some research you will also find most of the petrol models Toyota make if not all, still retain the stand temperature compensation type alternator and higher charge voltages, why because they were able to meet the anti pollution standards without reducing the charge voltages, it is only the diesel models that need the reduced voltages.

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Follow Up By: Dennis Ellery - Sunday, Mar 23, 2014 at 12:50

Sunday, Mar 23, 2014 at 12:50
My vehicle runs at 80 degrees C under the bonnet
Battery manufacturers specify much reduced charging voltages for that temperature.
This data is readily available online from battery manufacturers and suppliers.
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Follow Up By: The Bantam - Sunday, Mar 23, 2014 at 14:49

Sunday, Mar 23, 2014 at 14:49
Some battery manufacturers specify a maximum opperating temperature of 50C for certain batteries.

That puts them out of spec sitting under a shady tree in some locations in summer.

Various batteries tolerate temperature exreems better than others.
The temperature corrected charging voltages along with the need to correct will vary from battery to battery.

Most of the big cranking battery manufacturers publish very little in the way of detailed information on their batteries.

Hell none of the volume battery manufacturers will even give you an amp hour rating on a cranking battery.

There is also an argument that all under bonnet batteries in warm climates have a reduced life from ideal.....but the actual life achieved is considered acceptable.


The fact of the matter is that there are tens of thousands of vehicles out there running 14.2ish volts charging their under bonnet batteries ( HKB and Banmtam incluided) and there is not a string of what is considered premature failures.

But there is a strong documented base of information that shows there ARE many premature battery failures due to this limp wristed charging voltage in certain vehicles.

Cheers
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Follow Up By: HKB Electronics - Sunday, Mar 23, 2014 at 15:29

Sunday, Mar 23, 2014 at 15:29
The booster diode does not alter the alternators in built temperature compensation, it simply restores the base voltage to those similar to a standard alternator, ie those used in the petrol versions, by the way the petrol engine models will run hotter under bonnet temperatures than your diesel yet they still run standard alternators!

There are many thousands of boosters in use by happy users with no adverse affects being reported, the following was posted today on another forum, i believe it says it all:

"I did the Ctek d250s in the 120 series. I had it connected to a redarc relay to ensure the aux battery only charged after the main.. I was never really that happy with this set up. The aux battery never really got completely charged, particularly when camping at say Fraser or Rover Park where the aux battery ran down overnight and you then did short runs during the day. My theory was that the Ctek goes through multiple stages of charge before you get to the bulk stage every time you restart the vehicle. You need a good couple of hours of continuous running to get anywhere near full charge ( depending on state of discharge). I had endless fridge troubles with the battery running below safe voltage. In the end the Ctek somehow managed to boil the aux battery , about three months before I sold it. Made a mess of the inner guard that I had resprayed.

The 150 has the simple redarc relay and the voltage boosting diode. This works a treat. You can't beat good volts and solid amps."

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Follow Up By: Dennis Ellery - Sunday, Mar 23, 2014 at 15:59

Sunday, Mar 23, 2014 at 15:59
Bantam
I wouldn’t touch a battery that’s limited to 50 degrees.
If you buy equipment which doesn’t include specifications – that is your choice.
This is where we differ – I have no problem obtaining specs for the batteries I use.
I don’t go for the Micky Mouse stuff.
I think we are both wasting our time on this subject, it’s gone right off thread, and you and I are on different planets.
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Follow Up By: The Bantam - Sunday, Mar 23, 2014 at 18:35

Sunday, Mar 23, 2014 at 18:35
Ya got that right.
I don't know what plannet you are on But I am on planet Earth with my feet firmly on the ground.

Its one thing to get the specs its another to know what they mean.

cheers

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Reply By: steved58 - Friday, Mar 21, 2014 at 22:55

Friday, Mar 21, 2014 at 22:55
Hi smithie
I found that although I drove all day and ran the three way fridge on gas when camping I was running low on batteries I eventually found that I was putting charge into the batteries when driving but when stopped for lunch or a break during the day the three way was sucking the bejesus out of the batteries I fitted a fridge switch to the three way and no more low batteries could be your problem as a 184L fridge could easily reduce your days charge by 50% in just a couple of stops
cheers
Steve
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Reply By: The Bantam - Friday, Mar 21, 2014 at 23:09

Friday, Mar 21, 2014 at 23:09
Start with the simpe basics..and you may not have to look any further.

First and fomost....are you allowing sufficient time to charge your batteries....6 to 8 hours highway drive time minimum.

Is the vehicle alternator doing its job.....there are a number of issues...alternator voltage, modern alternator not suitable...and alternator just not big enough.
remember even though you have a 100 amp alternator...don't assume that it will put 100 amps into your batteries.....probably not even close...think in the 20 to 40 amp reigon...and then only as a starting charge rate.....that will deminish as the crage cycle progresses.

Look at the various items that can drain things.

This fan, concerns me......is this a small computer type fan....or is it a thermo fan from a radiator.....a largish computer fan should draw less than an amp....a full sized thermo fan will draw between 5 and 15 amps.

Don't assume that the caravan manufacturer knows what they are doing with electrics.


The power supply for the TV antenna booster should draw diddly squat...1/4 of an amp tops......it might flatten your battery if it was left parked up for a couple of weeks with no charger...but a significant issue in an over night stop..I dont think so.

yes check that the DC supply to your fridge is turned off.

Is the wiring to the supply connector heavy enough...and likewise the wiring from the supply connector to the batteries......10mm2 absolute minimum.

Remember don't assume that the caravan manufacturer knew what they where doing.

This "40 amp electro unit"...what is its function and how does it work..is it doing the job.

Step by step...look at the simple basics, before you look for complicated reasons.

OH these batteries...what sort of condition are they in...have you charged them individually, cheacked that they are charging, checked them for self discharge ( that they hold a charge) and checked that they run to capacity.

While it is possible to get a good long life out of batteries if they are treated right, it is also possible to get a very short and disapointing life from them by treating them wrong.

It is possible to kill a battery in a week.

Step by step smithy...oh if you do not have a multimeter...now might be a good time to buy one and learn how to use it.

cheers
AnswerID: 528832

Reply By: Sigmund - Saturday, Mar 22, 2014 at 06:28

Saturday, Mar 22, 2014 at 06:28
For battery health you need to do a slow drain test or take the rig to Battery World or the like.

I have 2 x 100 aH calciums and after 5 years they're down to 70% capacity, and that powers SFA.
AnswerID: 528848

Reply By: HKB Electronics - Saturday, Mar 22, 2014 at 11:03

Saturday, Mar 22, 2014 at 11:03
Another thing to consider is the three way fridge when traveling, if your running it off the same circuit being used to charge the van batteries ie connected to the van batteries then this is not going to help their charging.

A three way should be wired on its own circuit back to the cranking battery or charge source.

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Follow Up By: The Bantam - Saturday, Mar 22, 2014 at 17:34

Saturday, Mar 22, 2014 at 17:34
Yes indeed if the 3 way fridge is running on the same cable as the battery..particularly if the cable is inadequate or marginally adequate.

The current drawn by the fridge will cause voltage drop and may result in a total failure of the battery to charge.

Either you will have to use considerably heaver wire to accomodate the additional current or wire the two seperately.

Three way fridges are notorious for beeing inefficient on 12 volts..because pretty well without exception they are inadequately wired.

Actually...worst case....with the three way fridge going....low alternator output...and poor wiring your battery could be going backwards.

cheers
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Follow Up By: smithie12 - Wednesday, Mar 26, 2014 at 00:34

Wednesday, Mar 26, 2014 at 00:34
Thank you to all responses. My response to some points raised include:
I tow with a 2012 Prado which has one of the "smart" alternators.
I fully charge 2x100amp van batteries on 240V prior to leaving on trips.
I am currently testing the van to assess the battery draw for each individual appliance i.e. LED lights (very small), fridge on gas with small 12v thermal fan operating (used about 1/4 to 1/2 battery power over 24 hr period). The other power consumers to test include the water pump (5.2 amps) and the electric breakaway unit.

I am also considering options when travelling including second battery in the Prado to power Engel from 12v plug not the inverter plug will probably go with Redarc system.
Also looking at options for more charge to the van batteries from Prado. I have checked with multi-meter which shows that the majority of the power when travelling is going to the fridge on 12 v. Will need to consider capacity draw on the alternator to power all these things.

Regards


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Follow Up By: HKB Electronics - Wednesday, Mar 26, 2014 at 09:59

Wednesday, Mar 26, 2014 at 09:59
smithie12,

Fitting a booster diode such as mine unit or one of the others available will greatly improve your alternators charging ability, I would suggest you visit Pradopoint as this subject has been addressed in great lengths there.

Cheers
Leigh

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