Charging a 3rd battery - how?

Submitted: Friday, Feb 10, 2006 at 09:14
ThreadID: 30628 Views:2732 Replies:11 FollowUps:16
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I have a dual battery setup with a Rotronics controller.
2nd battery in the car to run the fridge, air pump, CB etc.
We have bought a camper trailer, and looking at putting a battery in the trailer for 12v lights and light use. Maybe 50AH.
Will keep the fridge in the car.

What do you think of running the 3rd battery off the 2nd battery via another charge unit?
My thinking is that I would like the 2nd battery to charge before the 3rd battery, and the third battery is only going to be connected once every few weekends.

Any comments appreciated.
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Reply By: Peter - Friday, Feb 10, 2006 at 09:35

Friday, Feb 10, 2006 at 09:35
Why not just take some leads off main battery with a manual isolate switch to anderson plug on back of car then on to trailer. Dont forget to fuse both ends.
For occassional use this should be ok
AnswerID: 154255

Follow Up By: Austravel - Friday, Feb 10, 2006 at 10:01

Friday, Feb 10, 2006 at 10:01
That's what I do, simple, cheap and effective to charge the other bank of batteries off the aux under the bonnet.
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FollowupID: 408192

Reply By: Member - Collyn R (WA) - Friday, Feb 10, 2006 at 11:39

Friday, Feb 10, 2006 at 11:39
Oldplodder

This is a relatively easy one.

Use an AGM battery in the trailer. AGMs hold a charge for up to a year and will charge well from a lower voltage than most other batteries.

Connect this battery, via a Redarc relay, across your existing second battery.

This way, the second battery must get to about 13.6 volts before the AGM starts to charge. It will then charge quickly and deeply and will retain that charge for a long time. The Rotronics will handle this well.

Post again if you need more help.
Collyn Rivers
AnswerID: 154277

Follow Up By: Mainey (WA) - Wednesday, Feb 22, 2006 at 22:32

Wednesday, Feb 22, 2006 at 22:32
Collyn, without starting an isolator war, after I had some problems with my Redarc battery Isolator I contacted Redarc and was E-mailed back by their CEO and I quote "we advise our customers about that" referring to the premice their battery isolator should only be used with two 'identical batteries' and not two 'different batteries', ie a Starter battery and a Deep Cycle battery as is stated on the installation specification sheet.
However he did state that their battery isolator was used in some mine site vehicles and had no apparent problems - but they did not run a fridge!

The full E-mail was, at the time, posted here on the EO forum, however it was quickly deleted, obviously it's contents were not meant for public viewing, so I will not repaste it here again today.
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FollowupID: 410651

Reply By: Wizard1 - Friday, Feb 10, 2006 at 14:55

Friday, Feb 10, 2006 at 14:55
Have the same issue with my a caravan. We already have our van powered from the second battery via an Anderson plug. The tip I got was to run the power from the second battery to an Arrid Twin Charger. Connect the Twin Charger to the van battery. The Arrid will stop drawing from the other battery when the third battery is fully charged.

Have a look at the Arrid website or give the 12 Volt shop (in Perth) a call for advice. I realise you are in QLD. There are no suppliers of Arrids in QLD so you have to order one.

Wizard
Gold Coast
AnswerID: 154307

Follow Up By: Member - Collyn R (WA) - Thursday, Feb 23, 2006 at 11:59

Thursday, Feb 23, 2006 at 11:59
Mainey
Am most interested in your response (re email). Would you send it to me privately please. I will take the matter up directly with Redarc's CEO.
Collyn
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Follow Up By: Mainey (WA) - Thursday, Feb 23, 2006 at 16:33

Thursday, Feb 23, 2006 at 16:33
Followup ID: 356991, Email from: Anthony kitel, Redarc CEO.
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FollowupID: 410775

Follow Up By: Member - Collyn R (WA) - Thursday, Feb 23, 2006 at 17:31

Thursday, Feb 23, 2006 at 17:31
Mainey
Where posted - cannot locate it
Collyn
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FollowupID: 410792

Follow Up By: Mainey (WA) - Thursday, Feb 23, 2006 at 20:51

Thursday, Feb 23, 2006 at 20:51
Ummm, as I originally posted it was removed very quickly, however fortunately I have retained a copy. (see how long it lasts this time, I will shorten the post)
FollowUp 6 of 6 posted 15 Feb 2005 at 21:18 - (followupID: 356991)
(Quote) In answer to your question:- In our discussions with a large battery manufacturer it was commented that it is IDEAL to use two IDENTICAL batteries in a dual battery system, and therefore we do pass that information on to our customers. We are UPDATING our website and we will REMOVE the confusion. Thanks for letting me know. (end quote)

The Redarc website was duly updated as was declared, with the previously shown Deep Cycle battery & Crank battery picture being eliminated to show two x 'batteries'.
Collyn, I believe Anthony kitel's integrity is beyond reproach.
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FollowupID: 410842

Follow Up By: Member - Collyn R (WA) - Friday, Feb 24, 2006 at 11:08

Friday, Feb 24, 2006 at 11:08
Mainey
Thank you for the clarification

Like you I too believe that the integrity of Anthony Kittel (Redarc's CEO) is beyond reproach, but I do not think the comment has anything at all to do with the Redarc product - but simply that from a battery maker covering its backside - the comment refers to (what a battery maker sees) as an ideal situation only.

They all do this in case some turkey does something like paralleling a 120-volt Nicad with a 12 volt AGM or something . . . and blows up both plus himself to b- y and what's then left of him then sues the charger maker.

Far-fetched? Consider this: some years back an NT truckie connected the 240-volt mains supply across his 24-volt starter battery - assuming it would charge 10 times faster. Truly.

I have just now discussed this matter with Anthony and he confirms that my interpretation is correct. He is also aware of this response - and confirms his agreement.

In practice, as long as the batteries are of reasonably similar type, each will charge and discharge at a rate relative to their respective capacity. It is perfect OK to parallel for example a 100 AH and a 10 Ah battery.

As an extreme example I have for over six years had a 12 AH 48-volt battery paralleled across my 48-volt 680 Ah home system.
Collyn Rivers
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FollowupID: 410968

Follow Up By: Mainey (WA) - Friday, Feb 24, 2006 at 15:20

Friday, Feb 24, 2006 at 15:20
Collyn,
You have said “but I do not think the comment has anything at all to do with the Redarc product – but simply that from a battery maker covering its backside – the comment refers to (what a battery maker sees) as an ideal situation only”

Collyn, may I offer another choice, as I was one of the two people involved in sending/receiving the original relevant E-mail information, I believe I can clarify the E-mail meanings accurately as I still have the original post to refresh memory :-)

As can be ascertained from their Email, Redarc clearly declare they “PASS THAT INFORMATION ON TO OUR CUSTOMERS” the information they declare they pass on is, it’s ‘ideal’ to use two ‘identical’ batteries, with their solenoid battery isolator, therefore conversely it can be stated, it’s obviously NOT ‘ideal’ to use two ‘different’ batteries as I was using!!

To actually understand the contents of Anthony’s E-mail to me as posted above, you would have to have first read my original E-mail to him.
The sole reason I had sent my E-mail to Redarc was because I was having problems charging my Deep Cycle battery and I was questioning Redarc about this, you say Anthony remembers this E-mail and I believe he possibly still has the original E-mail, that’s good, as then he will also be able to confirm what I have typed here!

When Anthony’s E-mail reply is read in context with my original E-mail sent to him, his comment “it is IDEAL to use two IDENTICAL batteries in a dual battery system, AND THEREFORE WE DO PASS THAT INFORMATION ON TO OUR CUSTOMERS” can be more easily understood, as he is referring to using two ‘different’ types of batteries, being a Deep Cycle and a Cranker battery.

When reading Anthony’s next comment; “We are UP-DATING our website and we will REMOVE the confusion.” It can be confirmed Redarc removed, with-in days, the Deep Cycle battery reference from their web site just as they declared they would in their E-mail to me, hence Anthony’s response to me “Thanks for letting me know” as is shown in his E-mail to me show’s there is/was no animosity between us in any way.

Collyn, you state above "In practice, as long as the batteries are of REASONABLY SIMILAR type, each will charge and discharge at a rate relative to their respective capacity.
It is perfect OK to parallel for example a 100 AH and a 10 Ah battery"

May I suggest a conventional Cranker wet cell battery is not a REASONABLY SIMILAR type to an AGM Deep Cycle battery and therefore will charge and also will discharge at very different rates when wired in parallel.

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FollowupID: 411017

Follow Up By: Member - Collyn R (WA) - Friday, Feb 24, 2006 at 18:53

Friday, Feb 24, 2006 at 18:53
Mainey

I can only really say that I spoke to Anthony this morning. He believes that his comments only make sense if quoted fully in context. He is aware of my response, and that it was to be published here - and gave it his OK. (I'm sure you will appreciate I cannot really get deeply involved in discussing a full previous posting that was apparantly withdrawn and that I have only seen in part).

I don't fully agree with you that an starter battery and an AGM deep cycle battery are that different from each's charge/discharge point of view, except that one will fully charge at 14.2 or so volts - and the other one wont.

Both have high charge acceptance and ditto discharge capability. The AGM may grab more of the initial available charge but as long as the starter battery is protected by a voltage sensitive relay that switches only once above the safe battery starting voltage (about 13.6 volts) there is no real problem. The starter battery is normally up to that charge level in a minute or so anyway - and from thereon the AGM can take whatever the alternator/regulator permits. It is possible the starter
battery may discharge slightly through the relay - but as that cuts out long before there is any non-starting risk, this solves that one.

The AGM will charge at close to 100% charge, whilst the starter battery will be limited to not much over 70%. But the starter battery would have reached and remained at that same state of charge (as it is intended to do) and in the same length of time even had the AGM not been there. The AGM gets nicely charged without affecting the starter battery in any way - what's the problem?

It'swould be a different matter were the two batteries to be a conventional deep cycle battery and any AGM battery - but that's rare - and I'd normally advise against it unless that deep cycle battery too were voltage relay protected.

I believe this issue gets clouded because unless on does the actual sum, it is hard to realise just what a tiny amount of energy is drawn by a starter motor even when starting a big diesel. It's only about 500 amps for 2 seconds. Electrical pea-nuts! It's less than that needed to run a side light for a few minutes!

Replacing the energy used is a breeze.
Collyn Rivers
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FollowupID: 411069

Follow Up By: ExplorOz Team - David - Friday, Feb 24, 2006 at 18:55

Friday, Feb 24, 2006 at 18:55
Mainey,

As per our private email I did some research and found the post has not been removed - it is located in thread 19729.
David (DM) & Michelle (MM)
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FollowupID: 411071

Follow Up By: Mainey (WA) - Sunday, Feb 26, 2006 at 15:08

Sunday, Feb 26, 2006 at 15:08
Thanks David, now Collyn will be able to read the thread in full, hopefully now he may also be able to understand how the comments do make sense when they are ‘quoted fully and in context’ as the relevant E-mail messages can now be read simultaneously, also it can be seen an almost exact same E-mail was also sent to two other respondents, therefore I would suggest it is not a once off E-mail at all, but a reply that’s very carefully and precisely worded, that shifts the responsibly of the statement onto an un-named third person!!

Collyn, Anthony was also very aware of the fact that his reply to me would be placed on a 4wd forum also, it’s actually mentioned in my E-mail to him, and I’m sure his response was designed with that in mind.

As to your comment, ““I don't FULLY agree with you that an starter battery and an AGM deep cycle battery are that different from each's charge/discharge point of view, except that one will fully charge at 14.2 or so volts - and the other one wont””

Ummm, Collyn, that is the point - they charge & also discharge differently!!!

If, they were 'identical' and did accept charge and discharge at the exact same rate then you would use the ‘cheaper’ battery, but fortunately AGM’s are an easier/better battery to use as a Deep Cycle battery simply because their construction and electrochemical characteristics enable them to charge much faster than a conventional Wet Cell battery, but you already know that, it’s in ‘the book’ :-)

* * * * *
(FollowUp ID: 353703) From NudeNUT
The answer to my question says:
in discussions with a large battery manufacturer it was commented that it is best to use identical batteries but Redarc do not request or require it.

(FollowUp ID: 355201) From Uncle
>In our discussions with a large battery manufacturer it was commented
>that it is best to use two identical batteries in a dual battery system.
>In practice however many of our customers are using two differing
>batteries (cranking battery and a deep cycle battery) and (like you)
>their systems have successfully operated over many years.

(followUp ID: 356991) From Mainey
(Quote) In answer to your question:-
In our discussions with a large battery manufacturer it was commented that it is ideal to use two identical batteries in a dual battery system and therefore we pass that information on to our customers. In practice however, the large majority of our customers are using two differing batteries (cranking battery and a deep cycle battery) and their systems have and continue to successfully operate over many years.
We are UPDATING our website and we will REMOVE the confusion.
Thanks for letting me know.(end quote)

I’m not sure why the “battery manufacturer” has to be quoted as to the working or possibly not working of a Redarc solenoid when Redarc is asked a direct question about their own product, as in each E-mail received (above) it can be clearly be seen the “battery manufacturer” is quoted as the responsible entity making the technical decision in each and every reply sent to those who took the time and also made the effort to ask the same question of Redarc.

The only difference is;
in my reply, Redarc actually declare they “would remove the confusion” shown on their website, and they actually deleted the ‘Deep Cycle battery’ from the diagram shown there, replacing it with an ‘auxiliary battery’
I did not ask them to do this, I asked them only to clarify the situation as to if a Deep Cycle battery could be used with a Start battery with their Solenoid isolator, nothing else, this change to their website was obviously their way of “removing the confusion” as they put it.

I believe by taking this deliberate action Redarc have actually shown their battery isolator as it is recommended to be used - by them, after all it’s their advice and their website, not a ‘battery manufacturers’ and not your’s or mine either, L0L.

As I said in my original post, I was not looking for an argument.

I have presented the available “written facts”, as can be read in the various E-mails which were produced by the other respondents, myself and Redarc on the same subject as is shown in the link to the relevant thread recently found by David.

Therefore, I believe this readily clears up any misunderstandings!
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FollowupID: 411375

Reply By: Member - Oldplodder (QLD) - Friday, Feb 10, 2006 at 16:54

Friday, Feb 10, 2006 at 16:54
Thanks every one so far.

Did think of the manual switch. But those senior moments are happening more often!

Will investigate the AGM battery and the Redarc.

First and 2nd batteries in the car should be reasonably charged from the weekly running around, so the third should charge pretty quickly on the first day out if it is a bit low. Saves the hassle of remembering to charge No. 3 before we go.
AnswerID: 154333

Follow Up By: Mike DiD - Friday, Feb 10, 2006 at 19:03

Friday, Feb 10, 2006 at 19:03
Think carefully about the size of wire to use from Engine compartment to Trailer Battery.

It needs to be a MINIMUM of 8Ga - i.e. the diameter of the copper at least 4mm - if you want the Trailer battery to charge in minimum time.

Mike
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FollowupID: 408349

Reply By: sandyngraham - Friday, Feb 10, 2006 at 19:41

Friday, Feb 10, 2006 at 19:41
Hi Oldplodder,

Seems you have all the components you require already except for the wiring to the CT. Speak to your auto-electrician, I have a 90ah AGM in the back of the Pathfinder and an additional 75ah deep cycle on the camper trailer, all works a treat powering lights, 80litre Waeco. One thing we added to our repertoire of goodies was a 120watt solar panel which allows us to camp remotely indefinately (of all the investments we made this was by far the best), as long as we have some sunshine, failing that we boot up the V6 generator to top up the 2 aux batteries.

Cheers

Graham and Sandy
AnswerID: 154361

Reply By: Richard & Leonie - Friday, Feb 10, 2006 at 20:14

Friday, Feb 10, 2006 at 20:14
Why not contact Rotronics? They have wiring diagrams for their equipment for your situation. I would be wary of doing anything before contacting them. You could compromise the efficiency of the system.
AnswerID: 154370

Reply By: Member - Norm C (QLD) - Thursday, Feb 23, 2006 at 12:31

Thursday, Feb 23, 2006 at 12:31
I have a similar set up currently. A 105AH Federal DC in the engine bay, isolated by a Cole Hersey (spelling?) solenoid. I then have 2 x 120 AH AGMs on the CT connected via a 175Amp Anderson plug and heavy duty double insulated welding cable which I fed through the chassis of both the vehicle and the CT. I went heavy duty as the AGMs could draw more than 50 Amps at times.

I then ran another cable back from the CT battery via a 50 Amp Anderson plug to a power point in the back of the 4B. This gives me the option to run the fridge (in vehicle) off the vehicle DC or the CT DCs. Extends stand still time without having to run vehicle or generator to charge batteries.

When the 175 Amp Anderson plug is connected, the AGMs are in parallel with the vehicle DC. This is very simple and works well. The only potential downside (as Collyn may well point out) is that if the AGMs have been run down they will draw most of the charging current at the expense of the starter and vehicle DC until they get a reasonable charge. I haven't found this problem as generally when the CT is connected we are driving a couple of hours at least.

If concerned about this, just use a Redarc or similar voltage sensing device. If you don't mind spending the money, use two. One to isolate vehicle DC from starter, the second to isolate CT DC from vehicle DC. This will establish a charging priority of starter, vehicle DC the CT DC. I think this is what Collyn has recommended above.

I confirm that AGMs are the way to go on the CT. They charge fast and hold their charge well. Well worth the extra money IMO.
AnswerID: 156651

Follow Up By: Member - Collyn R (WA) - Thursday, Feb 23, 2006 at 17:14

Thursday, Feb 23, 2006 at 17:14
I go along with all of that.
Collyn
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FollowupID: 410784

Follow Up By: Member - Oldplodder (QLD) - Thursday, Feb 23, 2006 at 21:07

Thursday, Feb 23, 2006 at 21:07
Norm,

Thanks.

Looks like AGms are the go for the trailer.
Didn't think about running a cable back to the car for the fridge, good idea.
We get about 3 to 4 days out of the N70ZZ.

I do have a solar panel. 80w, but am trying to cut down on what we carry! Where to mount it so it is safe and doesn't get too dusty.
Usually start the car every few days anyway for touring.

Need to get the alternator checked too if I do this. 260,000 since new and untouched. May be expecting too much from an old alternator.
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FollowupID: 410849

Follow Up By: Member - Norm C (QLD) - Thursday, Feb 23, 2006 at 21:26

Thursday, Feb 23, 2006 at 21:26
No worries OP. I did heaps of reading before I did mine, including a lot written by Collyn. He knows his stuff and I'm happy I was able to absorb some of it.

If you do the cable yourself, go to an electrical wholesaler. Much cheaper. The cable I used is about 25mm squared (each cable is about 10mm diameter) but has thousands of tiny copper strands so it still very easy to work with and bend through the chassis. Probably a bit bigger than necessary, but not much more expensive. Lots of people have trouble from cable too thin. Never heard of a problem from cable too thick.

I used the plastic tongue from floor sheets (pick it up off building sites where they are doing plywood or chipboard floors) to put through the chassis and taped the cable to it to pull through.

If you are not familiar with AGMs, this web site is a great place to start:
http://www.fridge-and-solar.net/batteries.htm

I bought my Fullriver AGMs from them. About $300 each for 120AH, so not cheap. But worth it I reckon. Val (male) who runs the business is very helpful. Even if you don't buy from him he will give good advice.

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FollowupID: 410855

Reply By: Member - Collyn R (WA) - Friday, Feb 24, 2006 at 11:19

Friday, Feb 24, 2006 at 11:19
May I draw respectfully people/s attention to my follow-up (410968) to Mainey's note re Redarc Relays. It hopefully clears up what could otherwise become a major misunderstanding re that product. (My reply has Redarc's approval).

Re large cable: the cable referred to in the posting above is welding cable. It is readily available and a fair bit cheaper than starter cable (but it is bulkier as it has thicker insulation). It's excellent for vehicle use - but just be aware that the very fine copper strands have a tendency to 'wicking' - that is drawing in moisture through capillary action. You can readily protect against this by using heat shrink tubing. It is also very flexible and should be supported throughout its length.

Thank you to various people for commenting on the assistance I may have been able to provide. It is genuinely appreciated.
Collyn Rivers
AnswerID: 156832

Follow Up By: Mainey (WA) - Friday, Feb 24, 2006 at 16:18

Friday, Feb 24, 2006 at 16:18
Collyn,
are you now suggesting the E-mail sent to me from Redarc is not authentic ?
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FollowupID: 411025

Reply By: Member - Collyn R (WA) - Friday, Feb 24, 2006 at 19:41

Friday, Feb 24, 2006 at 19:41
Mainey- with every respect - why on earth, or for what possible motive, would I doubt the veracity of yourself or of that (presumably part) email? Have you seen my earlier follow-up note?

I feel there is somehow some technical misunderstanding - but whatever it it is/was applies equally to every voltage sensing relay on the world market and hundreds of thousands of 4WD owners who have had systems wired this way for a fair few years now - with few reported problems.

I suspect that more has possibly been read into an email than was intended, or that the intent is clearer when in its full context. But as it is a private email that hardly anyone else has seen - does it really matter anyway?

If you do still see it as an issue I suggest it be taken up directly with Redarc because I reiterate I have no problem with their position as I understand it.

My interest in this is primarily that I have widely published (but not all maverick) views on parallel charging.

To reiterate I think this situation has arisen by a battery maker attempting to protect its corporate arse against people doing seriously stupid things - much in the way that fire lighter makers may state their products are not edible.
Collyn Rivers
AnswerID: 156913

Reply By: Member - Collyn R (WA) - Saturday, Feb 25, 2006 at 14:39

Saturday, Feb 25, 2006 at 14:39
Mainey (et al)
I have now read the original email. It reads:

"In our discussions with a large battery manufacturer it was commented that it is IDEAL to use two identical batteries in a dual battery system and therefore we pass this information to our customers.

"In practice however, the large majority of our customers are using two different batteries (a cranking battery and a deep cycle battery) and their systems have and continue to successfully operate over many years.

"We are updating our website accordingly . . .

The second paragraph, omitted in your subsequent posting, seems to make the 'issue' totally clear.

I totally agree with the battery maker's advice that, if charging in parallel it is IDEAL to have identical batteries, is spot on. How could anyone possibly disagree!

But you appear to exterpolate that advice to suggest that any arrangement OTHER than that is less than advisable - despite the next paragraph - which clearly suggests otherwise.

You will find that, if you traul through the battery literature, that most such comments re parallel charging relate to EXACTLY that. That is, they do not take account of any selective voltage switching that substantially precludes interference between the the charging batteries.

Indeed,my own books warn against indisciminate paralel charging. They strongly recommend the use of a voltage sensing relay for the alternator charging of disparate batteries.

Further, AGM batteries have charge/discharge characteristics that are in many ways closer to conventional starter batteries - than such starter batteries and conventional deep cycle batteries.

AGM batteries combine the high charge/ discharge capability of starter batteries - with the deep-cycle capability of good quality deep cycle batteries - and with fewer of the failings of the latter.

I receive a vast amount of reader and trade feedback and am not aware of a single instance of any failure known to have been caused by parallel charging - if protected by an adequate voltage sensing relay

The only exception are a few failures of AGM batteries charged at excessively high float voltages in hot areas. This latter mode of failure would have occurred whether parallel charged or otherwise.
Collyn Rivers



AnswerID: 157001

Reply By: Mainey (WA) - Saturday, Feb 25, 2006 at 23:59

Saturday, Feb 25, 2006 at 23:59
Collyn, below is the actual E-mail I sent to Redarc and then following is the Redarc E-mail reply, both contain the un-edited E-mail message.

As can be readily seen it was sent specifically for clarification by them about using a Deep Cycle battery and a Starter battery in the same vehicle with a Redarc solenoid system.

"Anthony Kittel, I'm requesting information recently posted on a 4x4 forum.
The question is; your isolator technical/installation sheet recommends the two batteries should be 'similar' however your website shows and also names a “Deep Cycle” battery and also a “Cranking” battery, which all battery manufacturers claim are not 'similar' in their intended use, one being for starting and the other slow deep discharge?
I believe your statement could be considered contradictory if not misleading, I eagerly await your reply"

* * * *
I then received this E-mail from Redarc.

(Quote)
In answer to your question:-
In our discussions with a large battery manufacturer it was commented that it is IDEAL to use two IDENTICAL batteries in a dual battery system and therefore we pass that information on to our customers. In practice however, the large majority of our customers are using two differing batteries (cranking battery and a deep cycle battery) and their systems have and continue to successfully operate over many years.

We are UPDATING our website and we will REMOVE the confusion.

Thanks for letting me know.
Anthony Kittel.
(end quote)

* * * * *

By reading the Redarc E-mail it can be readily ascertained the information Redarc “pass on to their customers” is-> it’s IDEAL to use two IDENTICAL batteries in a dual battery system, and therefore if you accept that as being true, then obviously the opposite must also be true, being; it’s NOT ideal to use two DIFFERENT batteries, yes even though some people use different batteries, which is actually contradictory to the information passed on to them by Redarc, as is claimed by Redarc, or am I missing something in the translation?

Redarc then state; "We are UPDATING our website and we will REMOVE the confusion"
Yes, “the confusion” is their term not mine, Redarc updated their website and duly removed the words ‘Deep Cycle battery’ from the diagram of the dual battery system and changed it to read 'auxiliary' battery instead, and that does, as they have said “remove the confusion” to use their words.

Therefore, I believe that could be construed as a very good written indication a Deep Cycle battery and a Cranker battery should NOT be used in the same vehicle, otherwise Redarc would have advised me differently, and also not had any need to up-date their website leaving their diagram showing the two different batteries on their website!

I'm only reiterating the communications written by Redarc, I’m not stating my personal beliefs, as my first battery isolator was a Redarc :-)

AnswerID: 157087

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