Split-Chargers & Bluemotion

@Dave Hallford-Nye Thank you for your response which I take to mean that I have the right end of the stick and that my posting, coupled with @T6 Dave's experiences, are a justified warning to others ?


Indeed. Sometimes you fall out of a tree and break your arm other times you fall out of a tree and are fine.

There will always be cases where no faults ever occur it does not mean that it is an efficient and safe method
 
Sorry guys. Wasn't trying to upset anyone, or engage in any sort of contest?!.., but the point of my reply was to ask why the failures occur, not to imply that they don't. If we can explain why something happens then we are more likely to apply the right solution and perhaps come up with new ways of tackling the problem. I think the fact that the question of VSRs keeps coming up on this forum indicates that some people are yet to be convinced. Personally I will err on the side of caution, but would still like an informed explanation of the facts.
 
@MartyMoose I always appreciate an enquiring mind. Don't take this the wrong way but you might find it worth googling "smart alternator and regenerative braking". There is a lot there, some simple and some technical and by including "VW" you could get information pertinent to the T6. Happy hunting because it is worth researching for authoritative sources and information.
 
As far as I am aware, it is down to sudden spikes and surges in the output of the alternator during the regen braking, this can then overload the wiring or VSR sending them into meltdown via either amps or voltage.. It can also overheat/cause damage to or cause the battery to out gas due to An excessively high charge rate.. Note some alternators/regen braking harvesting could be set different due to software updates.

Another point not well understood by some, is the fact that all AGM, gel batteries have valves on them that lift if the battery has a problem, and the gas vented is hydrogen (remember the Hindenberg?). For this reason, there is a vent hole on the battery casing, designed for this that should have a vent tube attached to remove these gases to atmosphere when the battery is in an enclosed space or inside the vehicle to prevent a buildup of this gas in this event, which could be ignited by a spark etc.

The smart chargers that are true ones have a temp probe that you attach to the battery as well. This monitors the battery temp and if excessive the unit will shut down, but you still need the vent tube to expell the gas in the event of a problem. When the excess pressure is released from the battery, the valves then close until the next time, BUT the gel/AGM is damaged at this point. You can also get a thermal runaway as well, which is not good.

So as you can see this has progressed from the old days, and the regen braking is now part of the vehicle emissions system, and even has a free wheeling pully that disengages it when not required to supply current, a vast change has been done to alternators and charging systems, and you need a product that is equally up to date to run the dual charging situation nowadays..

The clue is in Daves position, the fact that the VSR was used inappropriately, and the insurance have an investigator looking at the subsequent fire.. Would you like to have fitted that vehicles VSR? Sometimes you do not need to know the in depth to appreciate that something is not a good idea, and you have to have big wot sits to go your own path.

NO offence is intended by this post!
 
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I think that to suggest that a VSR is fine is utter rubbish. The only reason that people are reporting everything OK is because they never give their leisure battery any work to do and consequently it requires very little charging.
For someone who claims the credentials of an electrical control systems engineer to make this kind of statement is irresponsible.
VW may use a relay to seperate the two batteries but that relay is controlled by the same ECU that regulates the alternator, not by a simple voltage sensing circuit as it in most VSRs.
Having said all that, I don't subscribe to the fire risk theory either. Any fires that may have occurred are more likely to be due to bad workmanship, not incorrect kit. Any converters still fitting VSR systems on these vehicles are just confirming to us all what I have though for a very long time, they don't know jack shit about DC electrical systems!
 
Another note on batteries, slightly different tech, but a warning to all not to ignore the stored energy potential is the Sony laptop incidents and the Samsung phone incidents, as well as the Airbus battery problems.. Ignorance or overlooking the energy store and treating it casually can be regretted.. Another way of putting it is..
Assumption is the mother of all F?!&ups !
 
I think that to suggest that a VSR is fine is utter rubbish. The only reason that people are reporting everything OK is because they never give their leisure battery any work to do and consequently it requires very little charging.
For someone who claims the credentials of an electrical control systems engineer to make this kind of statement is irresponsible.
VW may use a relay to seperate the two batteries but that relay is controlled by the same ECU that regulates the alternator, not by a simple voltage sensing circuit as it in most VSRs.
Having said all that, I don't subscribe to the fire risk theory either. Any fires that may have occurred are more likely to be due to bad workmanship, not incorrect kit. Any converters still fitting VSR systems on these vehicles are just confirming to us all what I have though for a very long time, they don't know jack shit about DC electrical systems!


Well said Travelvolts and I agree there is a very good chance any fire caused was down to workmanship I hope to find out in the near future exactly what caused this, providing they will give me the info. There are so many supposedly fully qualified electricians that have very little knowledge about DC systems and this is very worrying! as the saying goes little knowledge can be more dangerous than no knowledge at all.

I do not want to create any tension and welcome an educated debate on the subject however an enormous amount of research has already taken place and the conclusion is VSR's and smart alternators are not a safe and efficient way of recharging an auxiliary battery.
 
A fascinating safety related thread, with considered knowledgeable responses, and represents exactly what is great about this forum IMHO as a newbie about to get and (safely) convert his first van.
But, the need for venting the battery , if under the seat, for example, does the base need a vent to the outside, or will the space around the battery suffice, remembering the Hindenburg? Thank you.
 
@Vinci. I have been in contact with VARTA (UK) after previous adverse comments by others on this subject and been advised of the need to vent to atmosphere external to the vehicle. VW achieve this by fitting a vent tube to the battery and it is shown on the ETKA schematic under second battery option. Note that hydrogen gas is hazardous to health as well as being flammable and it is a precaution against unforseen events. As the technology is so new it is safer to err on the side of caution.
 
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Yes, thank you.

For general information, Latest edition of VWBus has an article on this issue with a plug for a Sterling self managing electronic battery to battery charging system where mismatched batteries are not an issue.
 
Yes, sterling are marketing a lot of FUD at the moment.
 
@Loz might be FUD to you, but it's at leat got people aware/talking about the issues... Which are real. Including some, but not all converters!

FUD
Fear, uncertainty and doubt, usually evoked intentionally in order to put a competitor at a disadvantage.
 
@Loz might be FUD to you, but it's at leat got people aware/talking about the issues... Which are real. Including some, but not all converters!
Yes I totally agree, education is good, but can also lead to hysteria.
 
Yes I totally agree, education is good, but can also lead to hysteria.

Maybe this is needed to get the converters to STOP taking risks with people's cars by fitting VSRs instead of the required smart chargers! And do the job properly instead of staying in the stone age !
 
Maybe the real problem some people have, is the fact that suddenly owners are becoming aware of the issues, and seeing that maybe they have the wrong kit installed by a converter, and have issues.. My experience of trying to educate my converter leads me to believe that owners NEED to know what is potentially being fitted to their vehicles, and can then use this as a yardstick as to how good some of these so called "pros" are, and then make an informed choice to either use them or go elsewhere!
 
Maybe the real problem some people have, is the fact that suddenly owners are becoming aware of the issues, and seeing that maybe they have the wrong kit installed by a converter, and have issues.. My experience of trying to educate my converter leads me to believe that owners NEED to know what is potentially being fitted to their vehicles, and can then use this as a yardstick as to how good some of these so called "pros" are, and then make an informed choice to either use them or go elsewhere!
Hopefully end users will READ these posts and be more educated and be able to ASK questions when making enquiries to their prospective converters.
 
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