Split-Chargers & Bluemotion

[T6 Dave's Dad]

Having discussed this with @Pauly he has suggested that this be posted here to enable members to make their own decision to vent AGM Batteries installed within the passenger compartment. It should also be noted that the VW factory installation includes venting (the tube in question is shown on the ETKA schematic for secondary batteries).

MY COMMENT: Failure to install venting could invalidate both the manufacturer's warranty and your insurance in the event of an incident that can be attributed by either to the battery being unvented. It is their way of avoiding liability. MY COMMENT ENDS.

I contacted VARTA (UK) for their advice and the trail of emails is below with the latest at the top. The VARTA (UK) position with regard to venting is clear and you may wish to read the whole of my contact with them



From: VB-UK-Enquiries BG-EUR-DE
Date: Thursday, 16 February, 2017
Subject: RE: Contact Us Form Submission
To: John


Dear John,



We don’t supply the tubing, but any correctly sized tubing will be fine.

Best regards,

Debbie

Debbie F*******
Key Account Representative
Johnson Controls Power Solutions EMEA

Email:


================================================================

From: John
Sent: 15 February 2017 09:52
To: VB-UK-Enquiries BG-EUR-DE
Subject: RE: Contact Us Form Submission


Dear Debbie,

Thank you for that additional information and I will now seek to pass on the information and educate others. I do know that VW fit vent tubes to their leisure batteries but even a seasoned auto-electrician pooh-poohs that by saying "that is because they have always done it".

Is it possible to purchase vent tubes to fit or will any correct sized tubing suffice ?

Thank you once again for your assistance.

John

Sent from AOL Mobile Mail


===========================================================


From: VB-UK-Enquiries BG-EUR-DE
Date: Thursday, 15 February, 2017
Subject: RE: Contact Us Form Submission
To: John

Dear John,



AGM batteries gas at a much slower rate than conventional lead acid batteries so this is maybe why they are saying that it is not needed.

Best regards,

Debbie

Debbie F*******
Key Account Representative
Johnson Controls Power Solutions EMEA


===============================================================


From: John
Sent: 14 February 2017 17:22
To: VB-UK-Enquiries BG-EUR-DE
Subject: RE: Contact Us Form Submission


Debbie,

Thank you for your advice as there is some disagreement with installers about the necessity to vent an AGM Battery to atmosphere if installing within the passenger compartment.

John

Sent from AOL Mobile Mail


=========================================================


From: VB-UK-Enquiries BG-EUR-DE
Date: Thursday, 14 February, 2017
Subject: RE: Contact Us Form Submission
To: John

Dear Mr *******,



It is advisable to vent the battery so that any fumes that are generated will be taken outside of the vehicle.

Best regards,

Debbie

Debbie F*******
Key Account Representative
Johnson Controls Power Solutions EME


===========================================================

From: pulsedigitaltechnology@teamdetroit.com [mailtoulsedigitaltechnology@teamdetroit.com]
Sent: 12 February 2017 15:39
To: info-uk@varta-automotive.com
Subject: Contact Us Form Submission


There has been a submission of the form Contact Us through your concrete5 website.

*Comments/Question I intend fitting a Varta AGM Leisure Battery under the driver's seat of a VW Transporter. Is it advisable to connect a vent tube to vent the battery to atmosphere ?

*First Name: John

*Last Name: **********

 

[rod_vw]

I've commented on this thread before and have now opted for the Ring B2B + MPPT unit instead of connecting my leisure batteries in the same way that VW do in the California. In the past (3 x T5s) I have always used the BCM signal to switch my split charge relay as I never understood why anyone would spend money on a VSR when VW have provided the control already. Comparing cost it looks like £35ish for a VSR against £15ish for a high current relay. I agree having VCDS makes re-coding the BCM for 'battery isolation' simple for me.
It would have been nice to use the simple BCM control and monitor the voltages etc. over a period but the need to get the job done with the solar controller included persuaded me to go the way that I have. Time will tell if I have made the correct decision but with past experience of using the simple system will give me something to compare with. My 12v consumption will be Waeco CRX65, Eberspacher D2 Airtronic (heating and air circulation fan), LED lights, 300W Inverter and phone charging etc. obviously not all at the same time!

Rod

 

[travelvolts]

Well at least you will have the benefit of faster, more complete charging. You should see a big difference in battery performance Rod.

 

[travelvolts]

Having discussed this with @Pauly he has suggested that this be posted here to enable members to make their own decision to vent AGM Batteries installed within the passenger compartment. It should also be noted that the VW factory installation includes venting (the tube in question is shown on the ETKA schematic for secondary batteries).

MY COMMENT: Failure to install venting could invalidate both the manufacturer's warranty and your insurance in the event of an incident that can be attributed by either to the battery being unvented. It is their way of avoiding liability. MY COMMENT ENDS.

I contacted VARTA (UK) for their advice and the trail of emails is below with the latest at the top. The VARTA (UK) position with regard to venting is clear and you may wish to read the whole of my contact with them



From: VB-UK-Enquiries BG-EUR-DE
Date: Thursday, 16 February, 2017
Subject: RE: Contact Us Form Submission
To: John


Dear John,



We don’t supply the tubing, but any correctly sized tubing will be fine.

Best regards,

Debbie

Debbie F*******
Key Account Representative
Johnson Controls Power Solutions EMEA

Email:


================================================================

From: John
Sent: 15 February 2017 09:52
To: VB-UK-Enquiries BG-EUR-DE
Subject: RE: Contact Us Form Submission


Dear Debbie,

Thank you for that additional information and I will now seek to pass on the information and educate others. I do know that VW fit vent tubes to their leisure batteries but even a seasoned auto-electrician pooh-poohs that by saying "that is because they have always done it".

Is it possible to purchase vent tubes to fit or will any correct sized tubing suffice ?

Thank you once again for your assistance.

John

Sent from AOL Mobile Mail


===========================================================


From: VB-UK-Enquiries BG-EUR-DE
Date: Thursday, 15 February, 2017
Subject: RE: Contact Us Form Submission
To: John

Dear John,



AGM batteries gas at a much slower rate than conventional lead acid batteries so this is maybe why they are saying that it is not needed.

Best regards,

Debbie

Debbie F*******
Key Account Representative
Johnson Controls Power Solutions EMEA


===============================================================


From: John
Sent: 14 February 2017 17:22
To: VB-UK-Enquiries BG-EUR-DE
Subject: RE: Contact Us Form Submission


Debbie,

Thank you for your advice as there is some disagreement with installers about the necessity to vent an AGM Battery to atmosphere if installing within the passenger compartment.

John

Sent from AOL Mobile Mail


=========================================================


From: VB-UK-Enquiries BG-EUR-DE
Date: Thursday, 14 February, 2017
Subject: RE: Contact Us Form Submission
To: John

Dear Mr *******,



It is advisable to vent the battery so that any fumes that are generated will be taken outside of the vehicle.

Best regards,

Debbie

Debbie F*******
Key Account Representative
Johnson Controls Power Solutions EME


===========================================================

From: pulsedigitaltechnology@teamdetroit.com [mailtoulsedigitaltechnology@teamdetroit.com]
Sent: 12 February 2017 15:39
To: info-uk@varta-automotive.com
Subject: Contact Us Form Submission


There has been a submission of the form Contact Us through your concrete5 website.

*Comments/Question I intend fitting a Varta AGM Leisure Battery under the driver's seat of a VW Transporter. Is it advisable to connect a vent tube to vent the battery to atmosphere ?

*First Name: John

*Last Name: **********

OK, here is where this going to confuse the hell out of some people. Varta may make an AGM battery that has the facility to fit a vent tube, many manufacturers don't. So, if you fit a Varta battery then by all means follow their advice and fit the vent tube. If however you have a SLA battery from Trojan, Yuasa, Leoch, Optima to name but a few you will find that there is NO facility to attach a venting mechanism of any kind.
If your battery has the facility to fit a vent tube then fit it. If it doesn't don't lose any sleep about it. The amount of gas likely to be released is very tiny and would dilute in the atmosphere inside the van to insignificant levels.
The pressure relief valve on these batteries is set at 5 psi so it's not as though you are going to get huge jets of gas emitting from an overcharged battery! The reason that the Touareg has a vent tube is because the battery is fitted in a very enclosed space, the same could be argued for a factory fitted aux battery in a T4/5/6 with its rubber cover. Aftermarket installs do not have such an enclosure. Battery sheds for solar installations are very often crammed full of AGM batteries and will have less free air than the inside of a van but no venting of individual batteries.
I'm not stuck in the mud, I just base my comments on 50 years of experience working with batteries. Anybody have any stories of batteries exploding in vans?

 

[Loz]

I chose the ABX AGM for my portable split charge pack because it was totally sealed. Expensive but good quality.

 

[travelvolts]

Yes it's a very good battery. I have fitted many of them and never had an issue. In fact I use one as a starter battery in my Touareg. See those notches in the top plates? They are the vents (pressure relief ports).

 

[travelvolts]

Taken from the Sonnenschein web site "By design, AGM's low gassing characteristics mean there are no special ventilation requirements for Power-Tech AGM's in normal use. Like Deka Gels, simple ambient air flow through limber holes or air-slots are sufficient."

Read it for yourself here Absorbed glass Mat

So, draw your own conclusions. I think it fair to say that you should seek out the information relevant to your own particular battery and follow the manufacturers advice.

 

[MartyMoose]

Things have gone quiet on the original thread. I’ve not had the time to respond up till now, however, my credentials have been questioned and I have been misquoted. Sorry @travelvolts but I have the utter respect for your experience and knowledge in your field and I think you’re an absolute godsend to the members of this forum, however, I can assure everyone that my credentials are more than adequate to entitle me to an opinion on this matter. I have been designing electrical control systems for over 30 years, ac and dc, HV and LV, for military and industrial installations. I now specialise in writing the software for those systems. Its slightly patronising of others to suggest I do research on the internet to get a better understanding of the subject: the Internet can be very useful but it’s also the source of much misinformation and biased opinion. That said, I haven’t been doing what I do all these years without being willing to learn something new. That’s why I’m on this forum. If I’m missing the obvious then please let me know.

This is a VW T6 forum and that is the vehicle we were discussing. All I said was you could use a VSR. It just won’t charge your battery particularly well. To say it’s dangerous or unsafe to do so is misleading. Anything you connect to a voltage source could be if it’s not correctly specified or if it’s installed badly. Safety forms a huge and integral part of my work and profession, and to suggest I am irresponsible in this regard couldn’t be further from the truth.

A VSR is a relay; it doesn’t do anything magical. It gets switched on, it gets switched off. They are rated for many times the expected current flow and the electronics are designed to take a range of voltages. Based on the voltages from a VW T6 alternator it will be switched on for most of the time. I might even suggest that it would be switched less than the VW factory fitted relay. I appreciate that this is controlled by the ECU but what does it do to it? It switches it on, it switches it off. If the alternator is producing spikes and surges how is the VW relay immune to it? The ECU cannot respond that quickly. Any perceived ‘nasties’ from the alternator, going through any relay to the secondary battery, are also going to your main battery. Do we have to think about fitting a smart charger to that too now?

It’s horses for courses; if you are driving a delivery van around town and need a fully charged second battery then a b2b charger is probably the best option. A campervan running a fridge before the next electrical hook-up probably doesn’t need one. Each installation needs to be appropriate to its use and the correct components chosen accordingly. Believe me, before long someone will produce a VSR 'designed specifically' for smart alternators. The cynic in me says it won't be a lot different to what's out there at the moment.

The above is my opinion. It’s only based on my knowledge and my experience. You can take it or leave it but I don’t think it deserves to be called rubbish.

 

[travelvolts]

MartyMoose, thanks for explaining your views. I am sorry if you were offended by my remarks but all to often people with no real idea of what they are talking about come on these forums and spout a load of rubbish. Unfortunately sometimes they can sound very credible which leads to the uninitiated taking their erroneous advice. This is why I challenged you.
I think the point that you are missing about using a VSR system is that it has no control over the charging of the aux battery. As you rightly point out, it is an on or off situation leaving the aux battery at the mercy of the alternator which is being told by the ECU to do what ever the ECU believes that the vehicle battery requires. As we have already established, the vehicle battery is intentionally kept at around 80% so that it is ready to accept energy produced by the regen braking. This can deliver very high currents and very high voltages which could be damaging to the aux battery.
Given that there are still a lot of people and also "converters" who have their heads up their asses and still fit VSR systems based on the Smartcom 15 amp relay and 2 mm cable fused at 30 amps (if at all!) you can begin to see where the danger aspect comes in to the equation. This of course is information specific to this particular field and may have escaped your notice.
Can I draw your attention to this post made over the weekend on the T5 forum Electrical Fire - VW T4 Forum - VW T5 Forum
I am not one to jump to conclusions but in this instance I would have a bet on it!

The trend these days is moving more and more towards more wild camping and less time spent on hook ups so your final scenario of just topping up from the alternator between hook ups is becoming less and less relevant. I don't think that we will ever see a VSR specifically for SAs, the closest we are likely to see already exists in one of Sterling's current limiting VSRs but this still doesn't deal with the issue of no charge when the alternator is idle which is most of the time on motorway style driving.

 

[Dave Hallford-Nye]

Things have gone quiet on the original thread. I’ve not had the time to respond up till now, however, my credentials have been questioned and I have been misquoted. Sorry @travelvolts but I have the utter respect for your experience and knowledge in your field and I think you’re an absolute godsend to the members of this forum, however, I can assure everyone that my credentials are more than adequate to entitle me to an opinion on this matter. I have been designing electrical control systems for over 30 years, ac and dc, HV and LV, for military and industrial installations. I now specialise in writing the software for those systems. Its slightly patronising of others to suggest I do research on the internet to get a better understanding of the subject: the Internet can be very useful but it’s also the source of much misinformation and biased opinion. That said, I haven’t been doing what I do all these years without being willing to learn something new. That’s why I’m on this forum. If I’m missing the obvious then please let me know.

This is a VW T6 forum and that is the vehicle we were discussing. All I said was you could use a VSR. It just won’t charge your battery particularly well. To say it’s dangerous or unsafe to do so is misleading. Anything you connect to a voltage source could be if it’s not correctly specified or if it’s installed badly. Safety forms a huge and integral part of my work and profession, and to suggest I am irresponsible in this regard couldn’t be further from the truth.

A VSR is a relay; it doesn’t do anything magical. It gets switched on, it gets switched off. They are rated for many times the expected current flow and the electronics are designed to take a range of voltages. Based on the voltages from a VW T6 alternator it will be switched on for most of the time. I might even suggest that it would be switched less than the VW factory fitted relay. I appreciate that this is controlled by the ECU but what does it do to it? It switches it on, it switches it off. If the alternator is producing spikes and surges how is the VW relay immune to it? The ECU cannot respond that quickly. Any perceived ‘nasties’ from the alternator, going through any relay to the secondary battery, are also going to your main battery. Do we have to think about fitting a smart charger to that too now?

It’s horses for courses; if you are driving a delivery van around town and need a fully charged second battery then a b2b charger is probably the best option. A campervan running a fridge before the next electrical hook-up probably doesn’t need one. Each installation needs to be appropriate to its use and the correct components chosen accordingly. Believe me, before long someone will produce a VSR 'designed specifically' for smart alternators. The cynic in me says it won't be a lot different to what's out there at the moment.

The above is my opinion. It’s only based on my knowledge and my experience. You can take it or leave it but I don’t think it deserves to be called rubbish.

Hi Marty,

Thanks for the explanation and i hope you took no offence in my post. We are all here to better our own knowledge and have an educational debate

We were in the process of designing a smart alternator compatible VSR last year.

There are a few companies out there that do offer a relay/solenoid system that has been adjusted to work with smart alternators.

Even if the relay does work and allow some form of charging it will never be sufficient enough for charging a auxiliary battery the relay will constantly be engaging and disengaging ( I have seen this personally on a customers van)

The relays that have been designed are latching and have lower end protection around 12v to protect the starter battery and upper end protection around 15V to protect the loads and auxiliary battery from high voltages . These work to some degree but are not ideal and will reduce the performance of the batteries.

We sell over 1000 VSR's a month if there was a more cost effective feasible solution it would have been discovered by now.

 

[Loz]

Here is a good example where the VW VSR fitted to our Cali doesn't suit the new alternator setup.

Vehicle is running but vehicle battery is charged and the alternator has been shut down(idle) by ECU.

There is nothing running on the leisure side but there is a net drain on the leisure batteries flowing back through the VSR to the vehicle side.

 

[T6 Dave]

@Loz, it will do if the main battery is not fully charged, as it will equal them out, the main one is now a parasitic drain, that's my initial thoughts without going into the whole skinny!

 

[travelvolts]

Here is a good example where the VW VSR fitted to our Cali doesn't suit the new alternator setup.

Vehicle is running but vehicle battery is charged and the alternator has been shut down(idle) by ECU.
View attachment 5197
There is nothing running on the leisure side but there is a net drain on the leisure batteries flowing back through the VSR to the vehicle side.

That is very interesting. So, nothing going on in the ECU then to help with charging the leisure battery, in fact it is actually detrimental to the leisure battery as the vehicle battery is normally kept at around 80% it is going to draw from the leisure battery as Dave rightly says. Looks like VW have missed a trick here!

 

[T6 Dave]

@travelvolts thank you for your thoughts, @Loz is this a factory instal? As I note the CTEK next to the battery.. If it's an own, could you post a sketch of wiring so we could scratch our heads, maybe the CTEK is hooked to the alternator term, and not the mppt? Just guessing at the moment without having the full lowdown..

 

[Loz]

@travelvolts thank you for your thoughts, @Loz is this a factory instal? As I note the CTEK next to the battery.. If it's an own, could you post a sketch of wiring so we could scratch our heads, maybe the CTEK is hooked to the alternator term, and not the mppt? Just guessing at the moment without having the full lowdown..

Its all factory California with 2 leisure batteries.
The ctek photo is a red herring in this situation as it is a photo of the portable powerpack I built for the Touareg.

 

[Loz]

@Loz, it will do if the main battery is not fully charged, as it will equal them out, the main one is now a parasitic drain, that's my initial thoughts without going into the whole skinny!

Exactly, that's what I was demonstrating.

 

[MartyMoose]

It's more likely the other way round. The ctek mppt input is designed to accept a lower range of voltages,whereas the alternator input would have shut off at 12.8v. I would be surprised if there was no form of reverse current protection on the mppt though.

 

[Loz]

It's more likely the other way round. The ctek mppt input is designed to accept a lower range of voltages,whereas the alternator input would have shut off at 12.8v. I would be surprised if there was no form of reverse current protection on the mppt though.

sorry MM you misread the follow ups, there is no ctek in this scenairo just factory VSR

 

[MartyMoose]

Sorry, posts crossed in the air.

 

[MartyMoose]

It does appear to bear out what I've suspected though, that the ECU just switches that relay on: nothing fancy. What goes to one battery goes to the other.