redarc isolator question

Submitted: Sunday, Aug 17, 2014 at 07:30

ThreadID: 109164 Views:2683 Replies:8 FollowUps:31

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get outmore

ok so thier advertising blurb says the redarc wont connect to the aux until the main is fully charged but from my observation thats not true as as soon as I jump started my wagon the redarc kicked in.
which makes sense because as soon as the wagon started 14v was being sent to the battery and the redarc has no way of determining the resting voltage of that battery. the only voltage its being sent is the alternator volts.
and yes its correctly installed and seems to work otherwise kicking out a minute or so after the wagons turned off

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Reply By: Crusier 91 - Sunday, Aug 17, 2014 at 08:02

Sunday, Aug 17, 2014 at 08:02

This has also been on mind,

Do you here a clunk sound every time redarc kicks in?

I disconnect my aux battery every time we are not touring and leave the battery on charge in the shed.

Even with the engine off the aux leads are live!

From my understanding and witnessing, the alternator will charge both at the same time when ever needed, the redarc system just prevents the aux battery drawing from the main battery.

This can be a drain on the stock alternator especially when driving at night charging main and aux batteries and having 6 halogen spotlights in use as well as air-conds and so on. I see my voltage meter on the dash drop big time.

AnswerID: 537793

Follow Up By: get outmore - Sunday, Aug 17, 2014 at 08:19

Sunday, Aug 17, 2014 at 08:19

yes even when i was jump starting the redarc kicked in as it was being supplied volts from the donor vehicle

I cant see the advantage of them over a dumb solonoid??

they kick in when the vehicle is started and kick out when you stop (albeit a minute or so later as resting volts drop)

FollowupID: 822028

Follow Up By: Ross M - Sunday, Aug 17, 2014 at 09:27

Sunday, Aug 17, 2014 at 09:27

The Redarc may have the same effect as a simple switched dumb solenoid and the Redarc may be for dumb people who don't switch their solenoid on or off manually.

A normal solenoid can be made to turn on and off with the key for normal charging purposes. Just not voltage related, more brain related.
That way it is disconnected when it is required to be.

FollowupID: 822031

Follow Up By: cookie1 - Sunday, Aug 17, 2014 at 11:22

Sunday, Aug 17, 2014 at 11:22

Be careful if you intend to use a dumb solenoid though, most, if not all manufacturers of smart solenoids have spike protection built in, without it could cause your on-board electronics to have issues.

cheers

FollowupID: 822040

Reply By: scandal - Sunday, Aug 17, 2014 at 08:10

Sunday, Aug 17, 2014 at 08:10

The redarc isolator is just a simple relay, once the voltage reaches a predetermined level, it engages, once below a predetermined level it disengages, this is why they are cheaper than a "smart" battery management system.

AnswerID: 537794

Follow Up By: Crusier 91 - Sunday, Aug 17, 2014 at 08:19

Sunday, Aug 17, 2014 at 08:19

How is the predetermined voltage set?

The reason I ask is my redarc was installed when I had a 80amp hour aux battery, now I have a 100amp hour.

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Follow Up By: scandal - Sunday, Aug 17, 2014 at 08:41

Sunday, Aug 17, 2014 at 08:41

Its set by voltage, I cannot remember what it was, I think its 12.9 volts, once the redarc senses any more than this it will engage, the main battery could only be at 11 volts and need jump starting, but because the jumpoer leads have been attached the a vehicle that has more than 12.9 volts this will in turn trigger the redarc, battery size will be irrelevant, it just works on voltage.
My redarc engages pretty much straight away after starting, and disengage 5 or 10 minutes after stopping, some times longer.

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Follow Up By: The Explorer - Sunday, Aug 17, 2014 at 10:28

Sunday, Aug 17, 2014 at 10:28

..Redarc website/product summary refer to the REDARC Smart Start® as a solenoid ...not a relay (not sure that matters much but for the technically correct could cause psychological issues if wrong term used :)

They also state that voltage limits and time delay settings are "customisable"...but you have to ring them for details.

Cheers
Greg

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Reply By: OBJ - Sunday, Aug 17, 2014 at 08:32

Sunday, Aug 17, 2014 at 08:32

Have you considered phoning Redarc and asking them? I am sure they will have the answers you are looking for, and their source is credible. Their number is (08) 8322 4848.

AnswerID: 537795

Follow Up By: Crusier 91 - Sunday, Aug 17, 2014 at 08:58

Sunday, Aug 17, 2014 at 08:58

No.

I find the user's of products more credible and reliable than a manufacturer's propaganda.

Thanks anyway.

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Follow Up By: Member - bbuzz (NSW) - Sunday, Aug 17, 2014 at 09:47

Sunday, Aug 17, 2014 at 09:47

Redarc owners with problems should talk to the Technical staff at Redarc or send them an email.

They are the most helpful, informative and pleasant group of people you will ever meet. They are committed to getting your problems fixed and will stay with you for hours after your neighbourhood 'expert' has given up.

I was stuck in the boonies, on a hill, to get phone service, and they worked hard to get me going. They even rang me back so my mobile didn't pass the national debt.

No vested interest etc etc.

bill

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Follow Up By: Member - KBAD - Sunday, Aug 17, 2014 at 10:12

Sunday, Aug 17, 2014 at 10:12

IMO the red arc is a brilliant piece of kit it is voltage sensitive relay, off volts 12.7 on volts 13.2, As soon as the voltage drops to the 12.7 the relay disconnects and the batteries are isolated as soon as the voltage from the charge circuit which includes the main battery reaches 13.2 it engages. Simple and effective, it has an override feature that you connect to a switch with which you can override the voltage sensitive microprocessor and connect the batteries in parallel, when i bought mine (not sure now) it was one of the only ones available that had that capability. This was important to me so at the flick of a switch i can
1. Jump start my main battery from my second bat.
2. When using my winch i can have both batteries in parallel.
Cheers

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Follow Up By: olcoolone - Sunday, Aug 17, 2014 at 11:22

Sunday, Aug 17, 2014 at 11:22

Cruiser..... obviously never had dealing with Redarc?

Tell me another consumer company who telephone support staff are qualified engineers with in house knowledge of their products that they manufacture them selves in there own state of the art manufacturing facility in South Australia.

Their customer support in my opinion is the best in the industry and they back their products 120%.

If you ever get the chance to call in do so and they love showing everyday consumers around the facility.

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Reply By: The Bantam - Sunday, Aug 17, 2014 at 10:33

Sunday, Aug 17, 2014 at 10:33

This notion of " fully charged" is a contencious one and trips a lot of people up in a lot of discussions.

All these basic Voltage Sensitive Relays work the same.

They have no ability whatsoever to assess state of charge......they simply switch in when the primary battery voltage rises to a preset point and switch out when the primary battery voltage drops below a certain point......that is pretty well the beginning and the end of it.

The various manufacturers have differing opinions on where those voltage thresholds should be and some offer the ability to change them.....reasons for these voltages being selected is a whole discussion on its own.

The advantage of a VSR over a simple ignition triggered solenoid is that they allow the initial charge to be staged.....If the prinary battery has become discharged the VSR will not switch in till the terminal voltage has reaced a reasonable level and the primary battery has reached a reasonable state of charge.

Most of us our primary battery does not get significantly discharged so it comes up to voltage fairly quickly, so we don't see a significant delay in the VSR connecting the second battery.

Some VSRs employ stratergies to limit surge currents most do not.....getting solid information on this is hard.

cheers

AnswerID: 537802

Follow Up By: get outmore - Sunday, Aug 17, 2014 at 13:42

Sunday, Aug 17, 2014 at 13:42

and thats the issue Bantam - fine in theory but thats NOT how it works

it has NO WAY of detecting primary battery charge when the vehicle is running

just as putting a multimeter on the battery of a running vehicle wont read 12.7 it will read the alternator input - about 13.8-14.2

so in fact the redarc will always engage on a running vehicle

and in my example it will engage on a non running vehicle once you connect the jumper leads to a running vehicle

Im not just saying this for fun - I ran my battery flat and it in no way works as claimed and a bit of thought shows it can possibly work as youve just said

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Follow Up By: The Bantam - Sunday, Aug 17, 2014 at 14:35

Sunday, Aug 17, 2014 at 14:35

There are a lot of variables arround how batteries behave and how systems are instaled.

It may not seem that there is any delay...but there is...the time line just may not be what you expect.

I agree there is no way that a VSR will hold off till the primary battery is "fully charged"..whatever that means.

As I said there is quite a lot to be considered with those voltage thresholds and the implications.

Run the threshold too low and the VSR will cut in too early and not surpress the surge of putting two flat batteries on charge at once..leave the threshold too high and there will be a surge when the highly charged primary battery is connected to the secondary battery.

Now think on this.
IF you did get the primary battery to a high state of charge before connecting to the second battery......a great deal of that charge would then surge into the second battery and be lost in the primary battery in a matter of seconds.

I think a lot of what is said and written about VSRs is over simplistic and realy does not reflect actual reality......but the vast majority of customers would not gasp anything more complicated than the over simple discription of operation.

A while ago I got into a fairly deep and actally procuctive discussion about VSRs, voltage thresholds, current surges, current limiting and stuff....3 or 4 of us where actually getting to the bottom of a few interesting issues and putting together the pieces of the puzzle we each had.

But several other posters who where not actually contributing complained that the discussion was getting over complex and it all didn't matter...the thread was abandoned.

lots of people simply do not want to know the detail...people want to think that this is all very simple and it just works like they believe it does....and above all the product they are using is the best.

There are good reasons to use a reputable VSR over a crude simple solenoid.....some of the predominant issues relate to the crudity of the simple solenoids used...others relate to those voltage thresholds and the reasons why.

Cheers

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Follow Up By: Allan B (Member, SunCoast) - Sunday, Aug 17, 2014 at 15:16

Sunday, Aug 17, 2014 at 15:16

The Redarc SBI, along with other Voltage Sensing Isolators, does make an assessment of the starter battery State of Charge in order to operate. The battery terminal voltage will rise as the charge proceeds and by sensing that voltage the SBI can make an approximation of the battery's state of charge. Note that it is an approximation but sufficient for the very basic algorithm employed.

This is also the manner in which mains-operated multi-stage battery chargers operate. They sense the battery terminal voltage throughout the charging procedure in order to move through the several stages of charging. It is all they can do without measuring the SG of the battery electrolyte. But it works satisfactorily except with badly damaged batteries whose terminal voltage on charge is not indicative of the SOC.

In some superior multi-stage charging systems, the charging action is briefly suspended from time-to-time whilst the voltage is assessed but the constant monitoring used in the SBI is adequate for its purpose.
As I have said above, the starter battery terminal voltage will remain below 13.2 volts whilst ever the battery is at a low State of Charge thus keeping the SBI from connecting the auxiliary battery.
The action is quite simple and effective, but some would over-complicate the function unnecessarily.

Cheers
Allan

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Follow Up By: The Bantam - Sunday, Aug 17, 2014 at 16:32

Sunday, Aug 17, 2014 at 16:32

As far as I undersatnd the VSR makes no assessment of anything, it simply switches when the comparitor detects a voltage over the threshold.

There Is no assessment of state of charge and the threshold voltage could be reached under a greatly varying range of conditions depending on, temperature, exactly how the system is installed, what battery is in use, the age, condition and internal resistance of the battery and the charging voltage being delivered by the alternator.

In many situations the terminal voltage of the battery may rise rapidly.......way way faster than the actual state of charge.

This is why all the texts and those who know, harp about state of charge only being reliably assessed in a resting battery

All of these simple VSRs are compromise devices..this is why the threshold voltages vary from manufacturer to manufacturer.

Yes they are simple and they function perfectly adequately.

The problem is that the advertising departments sell them up as being more than they are.

The biggest joke is that they push the whole "smart" thing and prominently mention that "microprocessor" thing.

The truth is that all these VSRs and most of the multistage chargers use microprocessrs ONLY because it is chepaer and easier to design using them, than to do so using analogue electronics.

The whole "smarts" may consit of less than 20 lines of very basic code.
In the past it would have been done with entirely analogue components....and in fact still could be. and every bit as effectivly.

One of the things that has come to light and many people do not want to hear is that the"smart" multistage chargers that are OH so very popular can be fooled sometimes with unfortunate results.

None of these devices are as smart as the advertisers would have us believe.

cheers

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Follow Up By: Allan B (Member, SunCoast) - Sunday, Aug 17, 2014 at 17:16

Sunday, Aug 17, 2014 at 17:16

Well you don't "understand" too well then Bantam.
'Assessment' means to compare two or more elements, in this case a variable battery voltage and a fixed reference voltage. The SBI circuit (microprocessor or whatever) then executes an action, switches the solenoid on or off. It is simple but it is adequate for the purpose.

Of course there are variable factors that influence the behaviour from one situation to another, but what do you expect the manufacturer to do? ....... inspect every vehicle and tailor the device to suit.

As you yourself has said..... "Yes they are simple and they function perfectly adequately." So what is your point.... to bamboozle everyone into thinking that you are the Oracle? Wake up to yourself mate. Stop peppering your posts with such utterances as "microprocessor" and "lines of very basic code" and "analogue electronics" that have nothing to do with the discussion and are intended to parade your great knowledge. You know damn well that a manufacture is not going to mount half a dozen transistors and associated components when a single simple integrated circuit or microprocessor will do the job as well and cheaper. Stop pretending that because you can do it with discreet components that you must be so much more knowledgable and smarter and greater than everybody else.
And neither are you "as as smart as you would have us believe."

Cheers
Allan

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Follow Up By: The Bantam - Sunday, Aug 17, 2014 at 18:25

Sunday, Aug 17, 2014 at 18:25

I understand all too well......it is a dumb piece of electronics..it assesses nothing.

It makes no attempt whatsoever to determine battery state of charge, it is incapable of doing so.....it simply acts in a predetermined way to a change in voltage....nothing more nothing less.

My point is that so many people especially the advertising departments and the salesman on the floor, delibertaly try to give the impression that these devices are something more than a set of contacts driven by a voltage comparitor with a bit of hysteresis and time delay built in.

They have nothing that could be reasonably considered inteligence let alone being smart.

It is their simplicity that should be their biggest advantage....but people don't wnat to hear that.

cheers

FollowupID: 822066

Follow Up By: get outmore - Sunday, Aug 17, 2014 at 21:41

Sunday, Aug 17, 2014 at 21:41

bantam is correct. . ive seen it just yesterday.
the "smart " solenoid asseses nothing.
merely as soon as it detects the charging volts from the alternator it turns on no matter like in my case the battery was completely dead and seems to have dropped a cell. the redarc still connected the batteries due to the volts from the alternator

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Follow Up By: Allan B (Member, SunCoast) - Sunday, Aug 17, 2014 at 22:40

Sunday, Aug 17, 2014 at 22:40

You are nit-picking on the meaning of a word. Assess, measure, evaluate, compare all mean much the same thing, and that is what the SBI, solenoid, VSR or 'smart relay' does.

Of course your "Redarc still connected." If your battery had "dropped a cell" it would impose no load on the alternator so the terminal voltage would be the alternators nominal maximum output voltage, 14 point something.

Cheers
Allan

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Follow Up By: The Bantam - Wednesday, Aug 27, 2014 at 18:34

Wednesday, Aug 27, 2014 at 18:34

They do not not assess, measure or evaluate anything.

It could only be claimed to compare at a component level and not in any inteligent way, as a comparitor would be used with a voltage reference to set a threshold.

All those words you use mean very different things..particularly when used in this situation in relation to batteries.

There are no words that imply inteligence that can be used with accuracy in relation to these devices.

They react on a very basic electrical level to a change in voltage...nothing more nothing less.

The correct and accurate term for these devices is "voltage sensitive relay"....and that is the beginning and the end of it.

They are dumb devices.......not possessed of inteligence.....totally bereft of the ability to think.......let alone smart.

cheers

FollowupID: 822582

Reply By: olcoolone - Sunday, Aug 17, 2014 at 11:14

Sunday, Aug 17, 2014 at 11:14

QUOTE:ok so thier advertising blurb says the redarc wont connect to the aux until the main is fully charged"

Where does Redarc say this?..... I have never seen it in there marketing material and I think someone made it up outside of Redarc!

They are pretty honest on how the SBI series work and it has always been said in there marketing hype it is an isolator that disconnects the start battery from the aux battery.

No where in their instructions do they say it will charge the start battery first and then the aux battery.

AnswerID: 537804

Follow Up By: Allan B (Member, SunCoast) - Sunday, Aug 17, 2014 at 11:22

Sunday, Aug 17, 2014 at 11:22

They do actually..... in a manner of speaking......

Redarc instruction

See my post below.

Cheers
Allan

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Follow Up By: olcoolone - Sunday, Aug 17, 2014 at 11:35

Sunday, Aug 17, 2014 at 11:35

NO...... "once the start battery is charged by the alternator, the Smart Start will connect the axillary battery to the charge circuit".

The word is charged..... no mention of fully charged, part charged just charged...... maybe they have put it to simply.

If they said charged fully or to a % then yes that would indicate how getoutmore thought it would work.

And of course when the start battery is charged by the alternator the SBI will kick in.

The start battery has to receive a charge from the alternator for it to work.

Maybe they should of said "when the vehicle alternator starts charging, the Smart Start will connect the axillary battery to the charge circuit"

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Follow Up By: get outmore - Sunday, Aug 17, 2014 at 13:46

Sunday, Aug 17, 2014 at 13:46

probabally the best explanation - I was lead to believe and read that to mean when the battery is charged to a level of 13.2 volts it will connect to the aux battery

looks like thats not the case
- deal with it or buy a different system

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Follow Up By: Allan B (Member, SunCoast) - Sunday, Aug 17, 2014 at 14:35

Sunday, Aug 17, 2014 at 14:35

They are Redarc's words Olcoolone, not mine!
Perhaps you could talk to a Redarc rep and suggest they use "sufficiently charged" as an expression. That may satisfy the pedants.
I have always understood their operation and the shorthand expression did not worry me.

Cheers
Allan

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Follow Up By: olcoolone - Monday, Aug 18, 2014 at 09:59

Monday, Aug 18, 2014 at 09:59

It's simply one's interpretation of the word "CHARGED"...... This is the first time I have seen this question pop up on a forum as the SBI has been in the market since the start of time and most understand how it works.

Or instead of asking on a forum phone Redarc direct.

Get outmore raised an important question and is valid in seeking an explanation as if Get outmore had a misunderstanding many other will as well.

Redarc follows many forums but I will mention it to them.

FollowupID: 822087

Reply By: Allan B (Member, SunCoast) - Sunday, Aug 17, 2014 at 11:15

Sunday, Aug 17, 2014 at 11:15

The Redarc literature does not say "fully charged". It says...... "Put simply, once the start battery is charged by the alternator, the Smart Start SBI will connect an auxiliary battery to the charger circuit."

With respect, you may not see the subtlety but there is a difference between "fully charged" and "is charged". The standard Redarc SBI connects at 13.2 volts and a battery with its terminal voltage whilst on charge at 13.2v would be at a reasonable state of charge. Certainly with its terminal voltage at 13.2 it is at little over a volt below the alternator nominal output voltage of 14 point something so the current into the start battery would probably be of the order of 10A. At this point it is quite reasonable to connect the charging load of the auxiliary battery without excessively loading the alternator. It does not need to determine the resting voltage of the start battery.

If on the other hand, the start battery was at a low state of charge, its terminal voltage would stay below the Redarc cut-in of 13.2v and so prohibit connection of the auxiliary battery until the battery SOC had risen sufficiently. In practice this would rarely occur in a well maintained system as the start battery would not fall below 90% SOC and require little recharge energy. The large 'capacity' of a start battery is to ensure adequate available energy during cranking which consumes only about 1.0Ah during a normal start.
A simple isolator solenoid, enabled by the ignition circuit, will satisfactorily perform as an isolator but will not reserve the alternator to priority charge the start battery on the occasion when the start battery may be of low SOC. Furthermore, if winching from the start battery, the simple ignition-enabled isolator will enable heavy winching current to be drawn also from the auxiliary battery. This is OK if the aux circuit is arranged for that purpose but can otherwise cause overload of the aux main cable and fuses.

Redarc do not make outlandish claims in their literature and they publish a great deal of technical information unlike most other manufacturers/suppliers of similar products.
Furthermore, as has been said above, Redarc staff are highly knowledgeable and very willing to discuss and advise on their products and application over the phone.

Cheers
Allan

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AnswerID: 537805

Follow Up By: Member - Bigred13 - Sunday, Aug 17, 2014 at 16:01

Sunday, Aug 17, 2014 at 16:01

Ditto Allan ,Redarc are the experts in this field ,so a call would set any ones mind at rest . They have just been awarded the Australian Award for their innovation in electronics ,so they must be doing something right .
regards
John

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Follow Up By: The Bantam - Sunday, Aug 17, 2014 at 16:46

Sunday, Aug 17, 2014 at 16:46

I think the claim that "redarc are the experts" is a bit over the top.

They may be respectable players in the market and knoweledgable in the field but I do not believe they know any more than any of the other reputable players in the market..of which there are many.

In many cases the other reputable players make different choices than redarc...may be better, maybe worse or perhaps just different.

As for recieving an award.....yeh that is worth a little more than the piece of paper and less that the trophy.
Lots of questionable companies with average products recieve awards.

Redarc for the most part make respectable products.....but like just about every manufacturer, they have made a couple of stinkers in their time.

The sun don't shine from their nether reigons..though some would tell you it does.

cheers

FollowupID: 822061

Follow Up By: HKB Electronics - Sunday, Aug 17, 2014 at 16:52

Sunday, Aug 17, 2014 at 16:52

"If on the other hand, the start battery was at a low state of charge, its terminal voltage would stay below the Redarc cut-in of 13.2v and so prohibit connection of the auxiliary battery until the battery SOC had risen sufficiently"

Maybe if a 30A alternator was installed, with a modern vehicle with say a 100A alternator even with a dead flat cranking battery the alternator will force the terminal voltage of the battery above 13.2V within seconds of the vehicle starting. The kick in voltage setting of the VSR with large alternators gives no real indication of the SOC of the cranking battery, it is purely acting as a alternator has started charging indication and to connect the aux, or more importantly the alternator has stopped charging so disconnect the aux.

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Follow Up By: The Bantam - Sunday, Aug 17, 2014 at 18:42

Sunday, Aug 17, 2014 at 18:42

Exactly.

I have a large, commercia,l analogue, multistage charger...it is equiped with both current and voltage metes how batteries react watching both meters side by side is very interesting....and quite variable.

As I mention above, other manufacturers use differing voltage thresholds both higher and lower on their VSRs...and that can chage things.

The arguments as to why, can get quite convoluted.

cheers

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Follow Up By: wholehog- Sunday, Aug 17, 2014 at 20:08

Sunday, Aug 17, 2014 at 20:08

Good informative posts Bantam.

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Follow Up By: Member - Munji - Monday, Aug 25, 2014 at 09:08

Monday, Aug 25, 2014 at 09:08

Bantam

May I suggest that you start spending some time outdoors and stop watching meters for awhile. Next you will be carrying around a blood pressure gauge and notebook taking readings every fifteen minutes.
There is more to life then always being correct.

FollowupID: 822456

Follow Up By: The Bantam - Wednesday, Aug 27, 2014 at 18:46

Wednesday, Aug 27, 2014 at 18:46

I do spend time outdoors......I charge my batteries outdoors.

For those who have eyes to see and ears to hear and a brain to think, most of these observations take very little time and effort and only a little more time to think about.

Some just can't be bothered to find out the facts...then complian that things don't work or last.

Some of us possed of a moderate intelect, with a little effort and thaught manage to make things work where others fail.......that is what I do every day......it makes me a living.

cheers

FollowupID: 822583

Reply By: Member - Phil G (SA) - Sunday, Aug 17, 2014 at 23:04

Sunday, Aug 17, 2014 at 23:04

Not sure why this is so hard. Leigh has finally said what really happens above.

Jump start - Alternator kicks over and can supply up to say 100amps. Battery can only accept say 30 amps if its in good nick but flat. So the regulated voltage still rises quickly above the 13.2V sensing level for the Redarc and the aux gets charged as well. Nothing wrong with all that - that's the way it should be.

If the Redarc waited until the cranking battery was fully charged, it would have nothing going to the aux for the whole day.

AnswerID: 537829

Reply By: get outmore - Monday, Aug 18, 2014 at 09:19

Monday, Aug 18, 2014 at 09:19

any way.....

looks like the main cause of my trouble is a stuffed battery - at least I hope thats all it is

Ive been leaving it for 3 weeks between driving it

first time i did this it fired up no worries
second time it just turned over and I was able to jump start it using the second battery (I dont have the redarc set up to start off the aux)

3rd time it was dead as a doornail - just operating the dash lights

I jump started it - which if anyone has jump statarted a dead flat cruiser with light jumper leads would know isnt easy as requires leaving the leads atached for quit awhile before being able to start

and took it for a reasnable drive - Now I know a half hour drive wont charge a battery but should put enough in.
I pulled up and it restarted ok. Next day (24hrs later) I jumped in to drive it some more and it was dead flat again
I dont run auxillery stuff off the main except the spotlights and nothing was left on

AnswerID: 537832