start v deep cycle battery running engle - test

[weeds]

i started a test on the abovementioned this morning in prep for six days camping at easter.

background - the 3 way fridge in my poptop van failed a couple of months ago and as it was 26 years old and it having broken down for the second time in 12 months i decided to dump it.

the solution - as i have two engles i thought i would set one up in the van and use two spare start batteries i have had sitting around. i have wired them all in place along with a 65W solar panel.

the plan - as we are driving around during the day - leave the van fridge run off the two start batteries with the help of the solar panel. than everytime we are back at the campsite i will connect the van to the defender so that the two start batteries will be given a helping hand by the to deep cycle batteries in the defender. the defender wil also have a fridge

the outcome - as we normally go for a drive everyday i'm figuring the setup will work as i had the two engle running in the defender on my simpson trip.

the reason - its a pain going from the van to the defender to get food/drinks etc aong with i cannot justify buying deep cycles that are going to sit in the van all year and only get used a few times

has anybody ever run a fridge using a start battery???

[cewilson]

I have run a Waeco 80 litre off of a starting battery, but honestly not with much success. It worked great during the day whilst driving, and kept up quite easily. But when I stopped at night, it would drain the battery quite easily. (the battery is 830CCA).

After around 5 days on the road, I was waking up to a flat battery every morning - which gets really bloody annoying! https://www.aulro.com/afvb/

Personally, I would always recommend a deep cycle for running of accessories such as a fridge, whilst I recommend the opposite for winches!

Cheers
Chris

[DEFENDERZOOK]

<span style="color:darkred">a "start" battery will run a fridge the same as deep cycle will....


the difference is....if you flatten a start battery a few times you will greatly
reduce its service life.....
whereas a deep cycle battery will take getting deep discharged more than a start battery....

but deep discharging will shorten the life of that too.....
you need to try and avoid sending batteries flat for them to last longer....

the idea of a second battery is only so if/when you send it flat....
you in theory still have a good battery to start the car with in the morning....

drivesafe will probably be able to explain this better than me....
(as i am hopeless with words).....



a tip is to turn down the fridges at night (or even turn them right off in cold weather)
to save power....they dont get opened at night (unless you sleep walk)
so they stay cold....


if you are drawing enough power to flatten a start battery....
chances are you will flatten your deep cycle battery if you had it connected instead....
but you just wont know about it as you wont try to run a starter motor off it in the morning....</span>

[Pedro_The_Swift]

[quote=DEFENDERZOOK]

drivesafe will probably be able to explain this better than me....
(as i am hopeless with words).....

[/color]

dont be so hard on yourself,,
made perfect sense to me https://www.aulro.com/afvb/

[DEFENDERZOOK]

[quote=DEFENDERZOOK]

drivesafe will probably be able to explain this better than me....
(as i am hopeless with words).....

[/color]

dont be so hard on yourself,,
made perfect sense to me https://www.aulro.com/afvb/


<span style="color:green">
takes one to understand one......</span>

[Captain_Rightfoot]

Originally posted by cewilson
I have run a Waeco 80 litre off of a starting battery, but honestly not with much success. It worked great during the day whilst driving, and kept up quite easily. But when I stopped at night, it would drain the battery quite easily. (the battery is 830CCA).

After around 5 days on the road, I was waking up to a flat battery every morning - which gets really bloody annoying! https://www.aulro.com/afvb/

Personally, I would always recommend a deep cycle for running of accessories such as a fridge, whilst I recommend the opposite for winches!

Cheers
Chris
I have run our 40l Engel off our defender battery quite a few times without problems. I'm not sure if it is a deep cycle or not (it is what came with the car) but it has never looked like going flat. Something is fish here https://www.aulro.com/afvb/

[one_iota]

Something puzzles me...

My Waeco has a cut off switch that can be set to one of three settings so than when the battery drops below the set limit the fridge will switch off.

So regardless of whether I have a deep cycle battery or a cranking battery I can never drain the battery below that limit. Therefore for me a deep cycle is not an option because I can never cycle the battery if the fridge is the only implement attached. I understand that DCB's need to be cycled for long life.

Am I reading this correctly?

[DEFENDERZOOK]

Originally posted by one_iota

Am I reading this correctly?


<span style="color:darkblue">im not sure.....


a deep cycle battery is designed to accept a deeper rate of discharge....
compare to a normal battery.....and its not designed to run high current items...
such as starter motors and winches.....it is for lower current and for more hours......

lets say...for arguements sake....if you discharge a normal battery down to
9 volts regularly....it wont last long.....they need to be kept charged above 12 volts.....


if you do the same with a deep cycle.....it will last longer than a normal battery....
i dont mean will run the accessories for a longer period of time....
that is governed by the capacity of the battery...(AH)
i mean it will last for 2 or three years instead of 1 or less....</span>

[weeds]

an update - the fridge is set at 4 degrees

7:00am yesterday i started with 12.53V in the tank
8:00pm last night i had 12.32V - we had heavy cloud cover from 5pm on so the batteries should have been rested enough after taking charge from the solar panel all day
6:30am this morning 12.23V - i forgot to pick up some connectors yesterday therefore i could not connect the van up to the fender so that my two aux deep cycle batteries could lend a hand overnight. 0.09 of a volt drop sound s little low for a 10 hour period, i didn't disconnect the solar panel as it was in full shade therefore i wouldn't think would have an output.

will it last the five day test, i'm guessing not and as we have cloud cover today the solar panels output will be reduced a fare bit

if i get two to three days out of the setup i will be happy as it will reduce the amount of days i will have to have both fridges in the fender

i will probably put my new engle in the van for easter as it draws less current therefore longer life out of my makeshift van setup.

[DEFENDERZOOK]

<span style="color:darkred">there are a few things that will affect your results.....
such as....
how full the fridge is......
how often it gets opened.....
the temerature and airflow around the fridge....
how insulated it is....does it have the bag around it...



but it appears that the solar panel is running it during the sunny times....
and its only using the battery at night......so it should not go flat whilst there
is sun around.....if you have an overcast day or two....
the panel may need a hand to recharge the battery back to full charge....

the panel will run constatly while the sun is shinning.....but the fridge wont...
so while the fridge is off....the battery is being charged up....
when the fridge switches itself back on.....the panel will pretty much have enough power
to run it....so there wont be any draw on the battery.....

in plain english....the battery should be charging during the day....
and discharging at night.....just from the panel input....

do you know the specs of the panel....ie..how many amps its putting out...?</span>

[weeds]

hey zook

thanks for your comments, i am only playing around for the moment as i don't have the $$$ to replace the three way fridge with a three way or even a two way upright that was in the van.

the solar panel puts out 4 - 4 1/2amps for 4-6 hours of the day lying flat on the van however when camping and i'm around , at the moment the fridge is not being opened however its half full with bottles a of water.

i picked up a clamp amp meter today so i intend to record current draws from the fridge and current input from the panel as i have neve had actual figures

a mate of mine has gone away from deep cycles and is using an inbetween battery, ie its construction is somewhere between a deep cycle and start battery which seems to working good for him at the moment.

my theroy behind the start batteries is that they will accept charge quicker from my solar panel, maybe, kinda, at any rate the start batteries are old ones i had lying around so no real problem if a wreck them

[Omaroo]

From: http://auto.howstuffworks.com/question219.htm

People who have recreational vehicles (RVs) and boats are familiar with deep cycle batteries. These batteries are also common in golf carts and large solar power systems (the sun produces power during the day and the batteries store some of the power for use at night). If you have read the article How Emergency Power Systems Work, then you also know that an alternative to gasoline-powered generators is an inverter powered by one or more deep cycle batteries.

Both car batteries and deep cycle batteries are lead-acid batteries that use exactly the same chemistry for their operation (see How Batteries Work for more information). The difference is in the way that the batteries optimize their design:

* A car's battery is designed to provide a very large amount of current for a short period of time. This surge of current is needed to turn the engine over during starting. Once the engine starts, the alternator provides all the power that the car needs, so a car battery may go through its entire life without ever being drained more than 20 percent of its total capacity. Used in this way, a car battery can last a number of years. To achieve a large amount of current, a car battery uses thin plates in order to increase its surface area.

* A deep cycle battery is designed to provide a steady amount of current over a long period of time. A deep cycle battery can provide a surge when needed, but nothing like the surge a car battery can. A deep cycle battery is also designed to be deeply discharged over and over again (something that would ruin a car battery very quickly). To accomplish this, a deep cycle battery uses thicker plates.

A car battery typically has two ratings:

* CCA (Cold Cranking Amps) - The number of amps that the battery can produce at 32 degrees F (0 degrees C) for 30 seconds
* RC (Reserve Capacity) - The number of minutes that the battery can deliver 25 amps while keeping its voltage above 10.5 volts

Typically, a deep cycle battery will have two or three times the RC of a car battery, but will deliver one-half or three-quarters the CCAs. In addition, a deep cycle battery can withstand several hundred total discharge/recharge cycles, while a car battery is not designed to be totally discharged.

[Defender200Tdi]

You could always get yourself some Exide Orbitals. Built for Deep Cycling, but providing 750CCA, can accept recharging at a much higher rate than ordinary lead acid batteries, can be mounted at almost any angle, doesn't need ventilation...only $225 ea from your local Marshall batteries place. :wink:

Paul https://www.aulro.com/afvb/

[drivesafe]

Hi weeds, Zook pretty well covered the actual use and Omaroo covered the theoretical side of it.

As you have cranking batteries available at no cost, use them but I would like to clear up a few thing.

The use of the term deep cycle can be misleading. Originally and unless specifically naming the type of deep cycle battery IE, an AGM, when the term is used by itself, a deep cycle battery is a wet cell battery that has plugs on top of it to allow the battery’s water to be topped up and this is the type of battery you are talking about and the type I will be referring to.

Next deep cycle batteries should not be take down bellow 10.5 volts at any time and even taking them to 10.5 volts, the soon you can start recharging them the better, even if it’s slowly with your solar panel.

Deep cycle batteries can happily be used to start a vehicle but only now and then. If you use a deep cycle battery as your starting battery, you will be replacing it in a very short time.

You can use a cranking battery as you second battery but the continuos deep discharging may shorten it’s life and you don’t get the same stored capacity as a deep cycle of roughly the same size because the deep cycle can go to lower voltages on a regular basis and still have a long operating life.

Now this one you should consider when it comes time to replace the back up batteries. Deep cycle batteries tend to last longer that cranking batteries do, when left unused for long periods.

Last but not least, you say your plans are to be driving around during the day and then connect the back up batteries to the vehicle battery.

I’m not quite sure what you mean, but if you have an auxiliary battery in your 4x4, heres and idea that will allow you to charge your camp batteries quicker and to a higher state than your vehicle battery.

When you come back to your camp site at the day, if you have an inverter and a battery charger, you can hook the inverter up to the auxiliary battery in the vehicle and run an extension cord over to the camp batteries, to power the battery charger and charge the camp batteries over night.

One more point, I would be very surprised if you could get 4 amps for anywhere near 6 hours from your solar panel. No matter what size the panel is, as it gets hot during the day, the current output drops to at best, only about 2/3 of it max.

Cheers

[noddy]

Very interesting thread.

What is the impact (on the life expectancy of both deep and cranking batteries) of having no discharge.

I was always under the impression that when not using your deep cycle (ie with fridges, etc), you should try and have at least something draining it to preserve its life expectancy. Is this not correct? :?

Thanks

[numpty]

I run 2 starter batteries in my Stage 1, and have done for 18 yrs. I used to use a 3 way but last year bought an Engel. Have done 3 tests, admittedly not in Summer ( too bloody hot for camping), and have managed over 70 hours on 1 battery each time and still been able to start vehicle. I have fridge cycling between 1 and 4 degrees. This is not a scientific test but vehicle parked alongside camper with fridge in the car. The 2 batteries are Supercharge 700 CCA. Different batteries and conditions will of course give varying results, but this is my experience. Will be testing this to the max in July/August on an extended desert trip.
One day I will advance to a solar backup as well.
Perry

[drivesafe]

Originally posted by Noddy
What is the impact (on the life expectancy of both deep and cranking batteries) of having no discharge.


Hi Nobby, this is one of those things that is a little hard to verify but according to those who work with batteries in a research capacity, all seem to say the sulphration starts to degenerate wet cell battery’s capacity to be fully recharged the longer it is left in a no-charge, no-discharge state.

Applying some form of load periodically is supposed to reduce or even stop sulphation occurring.

As to what size load for how long and how often, I do not know.

Cheers and not much help there.

[weeds]

firstly an update

test abandaned at 4pm today - we have had full cloud cover all day and when i checked the batteries i only had 11.8V, bloody clouds. although the fridge was still running i hooked him back up to 240V. the temp in the van a 4pm today was 30 degrees so i guessing the engle would have been cycling on more than off throughout the day

outcome - i got 36hrs out of two start batteries with solar panel fitted, must check my solar panel is producing an output on a sunny day


Originally posted by drivesafe

1. Last but not least, you say your plans are to be driving around during the day and then connect the back up batteries to the vehicle battery.

I’m not quite sure what you mean,

2. One more point, I would be very surprised if you could get 4 amps for anywhere near 6 hours from your solar panel. No matter what size the panel is, as it gets hot during the day, the current output drops to at best, only about 2/3 of it max.

Cheers

ok i will try to clear some things up

in the defender i have 1 x start battery and 2 x deep cycle. this will always be my setup as i am happy with it. in the van short term i have 2 x start batteries

re: 1.
my plan was that when ever i was back at the campsite i would connect the fender and van together i.e via an anderson plug so that the two fridges (one in the van and one in the fender) draw from the four batteries ( two x deep cycle in the fender and two x start in the van). when i'm away from the campsite the alternator will look after the fender batteries and the solar panel will look after the batteries in the van.

re: 2.
i have been playing with my setup on the fender for eight months or so which the solar panel fitted. i would think its quite reasonable that i get 4amps/hr for 4-6 hours a day. most of the time the solar panel is in float mode as there is no load on the batteries. i have an amp gauge fitted between the regulator and the batteries. when the batteries have a load on them and the fender is parked to the north and its a clear sunny day my panel is always reading around the 4amp mark thoughout most of the day. i plan to record some readings from the amp gauge over the next couple of weeks

[cewilson]

Originally posted by Captain_Rightfoot+--><div class='quotetop'>QUOTE(Captain_Rightfoot)</div><div class='quotemain'><!--QuoteBegin-cewilson
I have run a Waeco 80 litre off of a starting battery, but honestly not with much success. It worked great during the day whilst driving, and kept up quite easily. But when I stopped at night, it would drain the battery quite easily. (the battery is 830CCA).

After around 5 days on the road, I was waking up to a flat battery every morning - which gets really bloody annoying! https://www.aulro.com/afvb/

Personally, I would always recommend a deep cycle for running of accessories such as a fridge, whilst I recommend the opposite for winches!

Cheers
Chris
I have run our 40l Engel off our defender battery quite a few times without problems. I'm not sure if it is a deep cycle or not (it is what came with the car) but it has never looked like going flat. Something is fish here https://www.aulro.com/afvb/[/b][/quote]


I can run a 40litre Engel easy too with no problems. Try an 80litre and see what happens :wink:

Nah seriously, the draw from this unit is quite impressive compared to my old Engel 40 litre. If I didn't need the extra room, I'd definetely go back to a smaller fridge.

But the missus gave me the ultimation of having warm alcohol, or buying a bigger fridge. Sorry guys, but warm rum and beer really sucks! https://www.aulro.com/afvb/

[matbor]

Originally posted by drivesafe
When you come back to your camp site at the day, if you have an inverter and a battery charger, you can hook the inverter up to the auxiliary battery in the vehicle and run an extension cord over to the camp batteries, to power the battery charger and charge the camp batteries over night.

Interesting idea, but how well does it work ?? 12v to 240v and then back to 12v to charge the battery, must be a easier way than that !!

[drivesafe]

Originally posted by matbor+--><div class='quotetop'>QUOTE(matbor)</div><div class='quotemain'><!--QuoteBegin-drivesafe
When you come back to your camp site at the day, if you have an inverter and a battery charger, you can hook the inverter up to the auxiliary battery in the vehicle and run an extension cord over to the camp batteries, to power the battery charger and charge the camp batteries over night.

Interesting idea, but how well does it work ?? 12v to 240v and then back to 12v to charge the battery, must be a easier way than that !![/b][/quote]

It depends on how you do your math

Going 12 to 240 and back to 12 will not be all that efficient but there is a major advantage.

But first, connecting batteries with different charge levels is not all that efficient but works and as for the theory that the batteries will be irrevocably damaged because the lower charged battery will pull the voltage out of the higher charged battery, this is what happens but other than loosing some capacity, I’ve never come across any problems where people have done it on a regular basis.

Now back to the inverter/ charger set up and I’ll use weeds arrangement as the exempt.

The main advantage is that you can charge the camp battery up from the vehicle’s auxiliary battery, over night and by the time you are ready to go for your drive in the morning the auxiliary battery will be low while the camp battery will be fully charged. You can’t get this result by simply connecting two batteries together in parallel.

Using this system, if you know that you will be doing at least 2 hours driving each day, you wouldn’t need the solar panel in the first place.

Another advantage is that if the is going to be a fair distance from the vehicle to the camp battery, use another 240v extension cord. This works out heaps cheaper than having to have long heavy gauge 12 dc cables.

[matbor]

Would be interesting too try...

[drivesafe]

Let us know if you do.

I was told of the set up by one of my customers about 10 or so years ago.

He had an F150 and trailer and would go up to the Gulf country every year for a month or so, Barra fishing.

He had two auxiliary batteries in the back of the F150 which he charged up while driving to and from his fishing hole.

He used the inverter / charger set up to charge a third auxiliary which was powering a large fridge back at the camp site which, as he put it, as he drained the beer, he replaced it with Barra.

It worked a treat for him.