Redarc battery isolator issue

Submitted: Tuesday, Feb 05, 2013 at 12:34
ThreadID: 100385 Views:13955 Replies:13 FollowUps:10
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HI all,

This is my first post here ,but much help has come my way from the vast experience on this site.

I recently had a problem with a redarc battery isolator. SB12

remote location ,flat batteries from being in the shade (solar not charging) engel on etc etc.. but a few people about so no biggie.

After a successful and properly carried out jump start (on the main battery)the redarc was flashing and not working .

I disconnected everything and it was obviously faulty.
Now I had a problem and quickly detirmeined that the control board had been spiked somehow during the jump start.

I wanted to remove the unit entirely but it would mean 12 high amp cable laying in the moving engine bay (not good) . I my wisdom i decided to remove the offending unit (the circuit board) by cutting it out and using the manual switch to control the solenoid wich was clearly ok.

I now had a useable manual system the worked well for the rest of the trip.I wondered why we need auto switching at all .

On returning to home I contacted the redarc people who kindly returned my call .

I wanted to purchace the faulty part (the circuit board) and was told that the whole unit is supplied as one and I should send it back complete.

I explained that the unit was cut out because it was faulty and the solenoid was in good order so why not just supply the faulty part ?

We established the it was under warranty and could be processed by a warranty claim procedure . I asked if having the faulty itm CUT out or with wires bared would be considered tampering to which he said that he did not know .

I asked him to consider that I did not want to remove the whole unit and just wanted the faulty part replaced and I would pay if needed.

So the young executive told me I was not cooperating as would be unlikely to recieve a claim or a part that was not available.

The solution for me has been to keep the manual solenoid an install a 100 amp shottky diode across the solenoid and whalla... better than ever .

The moral of the story dont need a computer to control charge to your auxillary battery just 20 dollars worth of diode , or just a manual switch . Its funny how things that seem important when at home are often unnecessary when on the road .

I did learn the there is a microprocessor in these redarc units and my 30 years in the trade , I conclude that this is not a place for a computer ,that in my case lost its brains.

AS for Redarc I think they should employ some kind of human being to handle their parts enquiries. A unit like this should never fail with a jump start ,however it may have been carried out.

Cheers to all

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Reply By: Rockape - Tuesday, Feb 05, 2013 at 13:13

Tuesday, Feb 05, 2013 at 13:13
I think you are being a bit harsh on Redarc. To start with I don't have any of there products but I have seen many good outcomes from customers claiming warranty on this site. Redarc have been known to send products to out of the way places and have them fitted to the owners vehicle. These people have contacted redarc first before doing anything and Redarc has come to the party even with gear that was out of warranty.

As for the place for electronics, if you saw what we did to electronics at work you would be shocked. They operated in extreme hot, cold and wet conditions with very little trouble.

There is a motor controller that runs a 1.5 megawatt motor form between .1m/s to 14m/s both forward and reverse and at maximum torque if required. It is supposed to have cooling air running through it. Problem is, that cooling air varies from between 0c to 65c and higher. It may run at these high temps for weeks on end with alarms going off 24 hours a day. In 15 years that cyclo convertor has never had a problem and it is a critical piece of equipment full of electronics.

AnswerID: 504118

Reply By: greybeard - Tuesday, Feb 05, 2013 at 13:21

Tuesday, Feb 05, 2013 at 13:21
Everyone can be misunderstood at different times.
From what you've written, you have performed a 'proper jump start' but, for reasons unknown, the voltage sensing controller on the SB12 has failed. You have then partially dissasembled the unit and requested a replacement under warranty for the failed subcomponent.
The Redarc people, in good faith, have accepted the issue as a warranty replacement, even though it has been 'tampered with'.

I'm not privy to the actual words used as we only have one side of the conversation, but it could be construed that there may well have been a little 'unhuman behaviour'.

For what it's worth, I've had excellent service and support from Redarc and have used their products most successfully over a few more years than I care to remember.

Well done on your succesful work around and may you never forget to manually switch off the solenoid.
AnswerID: 504120

Reply By: Member - Bruce C (NSW) - Tuesday, Feb 05, 2013 at 13:55

Tuesday, Feb 05, 2013 at 13:55
Hi Nicola Tesla number 3,

With a name like that and your 30 years in the trade, I pressume the electrical trade, I guess you have more than a passing idea of what you are talking about.

I also have questioned the need to have a sensative device controling the charge/discharge timing going to the Aux battery, especially as I also had one (not redarc) fail on me. Can't remember the circumstances now as it was a while back.

On my previous vehicle I controlled the isolating solenoid by the ignition.
Turn ignition on = batteries connected, turn ign off = batteries disconnected.
In other words, the KISS principal. Never had a problem.

I am currently running a Redarc unit which is working fine so I will leave it alone but should it fail it will be back to the KISS principal.

My suggestion to you is to have it working off the IGN as opposed to a manual switch. If you forget it you may end up regretting it.

Cheers, Bruce.
At home and at ease on a track that I know not and
restless and lost on a track that I know. HL.

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AnswerID: 504121

Reply By: MEMBER - Darian, SA - Tuesday, Feb 05, 2013 at 14:17

Tuesday, Feb 05, 2013 at 14:17
Ah Redarc.... a good South Aussie company :-o)... I think yours might be the first post I've seen anywhere from someone less than very happy with them. Only mentions I ever see are praise for their customer support. To be fair, most companies formally state that if you interfere with a product under warranty, you may as well not even call. I did drop in to their front counter one day to enquire about one of their products - that staff member went and got the electronics engineer who designed the product to discuss it with me - hard to beat that.
AnswerID: 504124

Reply By: Member - Frank P (NSW) - Tuesday, Feb 05, 2013 at 14:23

Tuesday, Feb 05, 2013 at 14:23
You say you had to "cut out" the circuit board. I just looked at the SBI12 in my Prado. As far as I can tell you only need to undo a couple of nuts and the module will lift off. Maybe if you'd done that you could have accepted Redarc's warranty offer, re-assembled your SBI12 and returned it for a swap.

Did the unit fail so it was always on, or did it just not operate. If it was just not operating, possibly you didn't need to remove the module, just hook up a manual switch .

One of the functions of the module, apart from sensing when to operate the solenoid, is to buffer the spike or inductive surge that the solenoid produces when it operates. This protects other electronics in the vehicle such as engine and transmission management computers (you can't rip them out if they fail) and less important stuff like expensive audio systems and whatever you have plugged into auxiliary sockets. Without the module you've lost that protection.

(Is that the function of the Schottky diode? - you didn't say where in the circuit you placed it.)


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Follow Up By: nikolatesla3 - Tuesday, Feb 05, 2013 at 15:28

Tuesday, Feb 05, 2013 at 15:28
Thanks for the responses guys ,
The shottky diode is just between the charge(main battery) and the second battery
voltage drop is .2 and yes it not ideal but the lenght of cables i have seen so called professionals use makes it far greater than .2 .

the manual switch bypasses the diode anyway

Some even run the cable all the way round the back of the firewall with the motive being roo strike .

A few years ago I used the oil pressure to switch the batteries together and it worked well .

Anyway, the less complex electronics the better . In my situation I had options but for the sake of reliability a solenoid and a switch will NOT suffer from spikes and any other noise like a computer will.

I have used redarcs for 5 years and this is the first failure which has alerted me to the reliability of the computer inside and the nature of failures that come with them .

I know what is possible and good design does minimise failures.
Im sure that the design engineers at redarc are continually improving their product and do try to give good service as long a customers dont try to solve the problem themselves.
Hindsight would have me carefully removing the unit and sending it back in one peice.

The things that we put into our vehicles can be life threatening and we do need to think about functionality and reliability vs features and convienience.

I have however solved the problem permanently , reliably , and cheaply and if any one can benifet from my experience then it was worth sharing .

I find the unavailability of a simple ,removable part , disapointing for a product that is such an important link in our vehicles electrical systems.

To throw away a perfectly good solenoid is not what i accept as reasonable for an austrailian company .

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Follow Up By: Member - Frank P (NSW) - Tuesday, Feb 05, 2013 at 16:08

Tuesday, Feb 05, 2013 at 16:08
NT3, thanks for your follow-up. I see where you're coming from re throwing away a large, expensive component because a small sub-component has failed. It's frustrating but sadly it seems to be the way of the world.

Quote: "a solenoid and a switch will NOT suffer from spikes and any other noise like a computer will". I may not have explained myself very well ... I didn't mean spikes affecting the solenoid or its module (if present). I meant spikes generated by the solenoid itself feeding back to the rest of the vehicle. Rather than take up space here trying to explain I'll let this link explain it for me. I'm sure you're aware of it, and if so I apologise for flogging the point, but it seems to me you've lost the protection to the rest of the vehicle that the failed module provided when the solenoid is de-energised. Maybe you need another diode across the coil of the solenoid to suppress the surge.

Love your simple Schottky solution. It's very cool.


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Reply By: Ross M - Tuesday, Feb 05, 2013 at 14:29

Tuesday, Feb 05, 2013 at 14:29
The Redarc stuff seems to work well and most claims are generally reported in a positive manner.
However, your experience is the reason I have made my own system.
It can be either set to switch on the relay as the ignition is turned on or standby ready, waiting for my push of a momentary switch to initiate the lock up.

The system just uses two switches and two small interlocking relays to do this process.

Similar to your manual system, it is trouble free and charges just the same as expensive stuff does.

There is a lot of stuff in 4wd's that just doesn't need to be there and is purchased because of perceived need rather than real need.


AnswerID: 504127

Follow Up By: PeterInSa - Wednesday, Feb 06, 2013 at 15:02

Wednesday, Feb 06, 2013 at 15:02
I have similar to Ross M:

Ignition turns on 2 realys to share the current, joins the Batteries with appropriate fusing. To me this setup needs more battery monitoring that a battery isolator unit.

Mate offered a Battery Isolator to me at no cost ( Not a Redarc) that I turned down.

Have had dealings with Redarc on other projects and always found them to be helpful and willing to take the extra step. eg. Me talk to a Teckie.


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Reply By: Dennis Ellery - Tuesday, Feb 05, 2013 at 15:39

Tuesday, Feb 05, 2013 at 15:39
2 years ago I had a Redarc fail – it was out of warranty.
I rang them and within 2 days they had a new solenoid with their agent for my pick up, swapped free of charge – I was impressed with their service and professionalism.
AnswerID: 504130

Follow Up By: nikolatesla3 - Tuesday, Feb 05, 2013 at 16:40

Tuesday, Feb 05, 2013 at 16:40
Good for you Dennis,

That's the attitude that I have had previously in my own business and was paid to do in other businesses.

If i were the service guy taking my call i would have just sent the faulty part and made it my mission to work out why it failed so that product improvement could continue.

The person with whom I was communication with had little or no technical ability . He seemed like a sales person that was losing a sale .

cut wires have nothing to do with warranty , as long as the failure was not caused by the cutting..which in my case was the most expedient thing to do in the heat, dust, and wind on the side of the road that morning.

It could be that some of the companies we rely on are finding it tough with competition from china and I suppose that not being willing or able to supply a known part that does fail are losing their grip on the customer base that put them where they are.
For all I know they only have complete units and their computer says NO to anything that doesnt line up in the eyes of an underpaid, underpowered future executive.

As a general statement that tag that says warrany viod if removed is just a bluff that works on those who have no ability and probably will do damage if they poke around in there.
design and manufacturing faults are never caused by a silly sticker are they?

any way it has been interesting learning how different our expectation can be .
I will stay diy and simple for the foreseeable future
Thanks for the input and if there is a place to put diy circuits here I will happily contribite a full diagram with pictures etc .

Please let me know the right section if there is one
FollowupID: 780921

Follow Up By: Member - Bruce C (NSW) - Wednesday, Feb 06, 2013 at 18:51

Wednesday, Feb 06, 2013 at 18:51
As your circuits and pics relate to this thread then why not put them up here. I for one would be interested and I am sure many others would be also.

Cheers, Bruce.
At home and at ease on a track that I know not and
restless and lost on a track that I know. HL.

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Reply By: BarryR1 - Tuesday, Feb 05, 2013 at 17:45

Tuesday, Feb 05, 2013 at 17:45

it seems a bit odd that you are a first time poster who goes out of his way to annonymously malign a company that most people find positive experiences with. It would be very interesting to see what the rep at Redarc actually has to say about the exchange because I'm pretty sure given the content of your post, their recollection would be somewhat different and I'd suggest a damn sight more credible.

I have a SB 12 and as a previous poster has said, there is simply no need to cut anything. Two screws and the control unit slides off. From my experience, Redarc would bend over backwards to help you regardless.

There are a lot of snake oil merchants out to pump their own agendas at things like 4x4 shows. If I had a dollar for everytime I've heard "Why would you buy one thing that does it all because if one area fails, it doesn't should have these three separate things of mine at twice the cost...." Pure rubbish.
AnswerID: 504138

Follow Up By: Member - Bruce C (NSW) - Wednesday, Feb 06, 2013 at 19:03

Wednesday, Feb 06, 2013 at 19:03
Hi Barry,
If NT3s intention was to malign Redarc, which I doubt, then it back fired as the feedback here is overwhelmingly positive for Redarc. However their inability, or decision not, to supply the small part in question has not served them well. It is good feedback for the company in my opinion and gives the sales department some area to create some improvement. Why they could not have offered the small device at a price is also something they can work on at redarc. We all have room for improvement and having once work for a major multinational I can tell you that feed back, positive or negative, was worth as much as the millions spent on advertising.

Cheers, Bruce.
At home and at ease on a track that I know not and
restless and lost on a track that I know. HL.

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Follow Up By: olcoolone - Friday, Feb 08, 2013 at 13:03

Friday, Feb 08, 2013 at 13:03
Be able to be supplied with a small component of a item vanished with the dinosaurs........ very few manufactures off every component as a spare.

Working a multinational company you would understand the term "ECONOMICALLY UNFEASIBLE".

In most cases the individual component is more expensive then the complete item.

The thing is Redarc did not say they would not replace the whole item under warranty..... it was his doings and approach that changed the outcome.

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Follow Up By: Member - Bruce C (NSW) - Friday, Feb 08, 2013 at 14:41

Friday, Feb 08, 2013 at 14:41
Hi Olcoolone,
The term 'Economically Unfeasible' is a smoke screen.

Sales departments can and do anything they feel the need to do, if the mood takes them, and ditto for the service dept.

I agree that NT3 has gotten on the wrong side of the guy at the other end of the phone, but the customer is always right, even when they are wrong.

get a replacement solenoid from Sidewinder ($25) See here and replace the Redarc unit and make another approach for a warranty claim and send them the whole unit. Got to be worth the try.

Cheers, Bruce.
At home and at ease on a track that I know not and
restless and lost on a track that I know. HL.

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Reply By: nikolatesla3 - Tuesday, Feb 05, 2013 at 18:06

Tuesday, Feb 05, 2013 at 18:06
hey cool down a bit ..this was my experience thats all .
2 screws ?? mine had a small nut on the blue wires to a ground that I did not have a spanner for.
But Not my point .. I could NOT buy the part thats my point ...not trying to put down any body , not even those who are already there and sure there are people whos wits are not working properly.
this forum might be the wrong place .
Ill go back to lurking and thanks again for all you guys who are constructive
AnswerID: 504140

Follow Up By: Member - Bruce C (NSW) - Wednesday, Feb 06, 2013 at 19:11

Wednesday, Feb 06, 2013 at 19:11
NT3, dont be a lurker, be a contributor. It is apparent you something to offer.

But be warned, sometimes when you make a statement the worms come out of the woodwork and feast on you. We all get it from time to time. It is part of the toughening up process that goes on here. LOL

PS don't forgret to post that circuit and pics, please.

Cheers, mate.
At home and at ease on a track that I know not and
restless and lost on a track that I know. HL.

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Reply By: Member - Phil G (SA) - Tuesday, Feb 05, 2013 at 21:20

Tuesday, Feb 05, 2013 at 21:20
Your Redarc may have been behaving normally. In the instructions it says that if it detects a high current draw across its terminals for greater than 1/2 second and creating a voltage drop of at least 1 volt, then it automatically shuts off and flashes the LED light 3 times. It reassesses again after 20 seconds. But a flat aux battery with a decent alternator might create this situation. I can understand why Redarc wanted the unit back. The fact that you wouldn't return it made life difficult for them.

But if anyone has an isolator fail on our trips, we simply mount both leads to the one isolator terminal to bypass the isolator and use it as a single battery. If we need to isolate the cranking battery, just disconnect it's earth lead (although I carry a spare earth switch in my spares).

Others I know do just fine without automatic isolators - just parallel their batteries and use a decent kill switch to isolate on the rare occasion when needed. No Schottky diode required and no 0.3V voltage drop.

AnswerID: 504159

Follow Up By: Lex M - Tuesday, Feb 05, 2013 at 22:22

Tuesday, Feb 05, 2013 at 22:22
Read the instructions........... What the!!!!!!! :-)
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Reply By: olcoolone - Thursday, Feb 07, 2013 at 08:23

Thursday, Feb 07, 2013 at 08:23
Some times the customer s are there own worst enemy.....

The way you have come across to me with words like "young executive", "30 years in the trade" and "I conclude that this is not a place for a computer" that you already had an idea of how you were going to attack this problem.

Young executive........
Everyone who mans the phones in a technical role are qualified electronics engineers.

30 years in the trade........
So you are an auto elec with electronics experience, 30 years in the trade means little if you have been out of it for 10 years or you trade experience isn't related to this.

I conclude that this is not a place for a computer.......
You have done extensive testing to come to this conclusion, computers and microprocessor have been around in automotive for over 30 years with no real problems....... might have to let Redarc and every one else who supplies microprocessors and electronics to the automotive industries know this, they might have to do a world wide recall on anything electronic!

We use and sell Redarc products and can not speak highly enough of the after sales support.

Did you count the number of flashers the Redarc was flashing...... this indicates what the fault could be and there are a few codes that can be produced.

I don't under stand why you had to cut it out as all we have ever had to do was move the terminals from one side of the solenoid to the other joining all the wires together...... and getting you out of trouble....... plus the little microprocessor module is only held on with removable terminals........ cutting it out doesn't seem to be the normal tradies way....... unless you a butcher.

It takes us about 2 minutes to remove the module.

You could of called into any Redarc dealer (and there are many) and had it replaced or phoned Redarc and they would of arranged it.

Instead of complaining here why not give Anthony Kittle a call...... he's the Managing Director of Redarc and he is approachable, not many companies you can do that with.

We have jump started many many vehicles with SBI12's and never ever had a problem and seeing you are a tradie with 30 years experience you should know it's impossible or harder and in most cases more expensive to get a single component these days..... it's not economical for companies do to it.

Maybe if you handled it different you would be the proud owner of a new SBI12...... for free.

AnswerID: 504239

Reply By: AlbyNSW - Thursday, Feb 07, 2013 at 08:56

Thursday, Feb 07, 2013 at 08:56
Technicalities aside, shouldn't the Redarc have prevented a flat cranking battery in the first place ?
Or was it faulty before the jump start or do you have your batteries wired up differently o bypass it?
AnswerID: 504240

Reply By: anglepole - Thursday, Feb 07, 2013 at 10:04

Thursday, Feb 07, 2013 at 10:04
Hello nikolatesla3,

In my dealings with Redarc I have found them very helpful.

There are several reasons why they would like the faulty unit back. May be they want to check out what is wrong, could be faulty components, problems with build and so on.

Secondly you say you have "30 years in the trade" that could mean any thing. You could be an Avionics designer for Boeing or you could be selling car batteries in the local servo.

Redarc may see them selves as liable if you have wrongly diagnosed the fault or installed it incorectly and say your vehicle catches fire.

I believe they have done the right thing.
AnswerID: 504244

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