Battery Blues

We have a Nuevo 2008 with the MES control panel. I am spending my life charging the batteries, both vehicle and leisure and it doesn't help that I have to manually switch from one to the other on the control panel when they need charged.
Can anyone tell me if there is some gizmo that I can buy which will allow me to leave the van on hookup and it will direct charge to the batteries as they need it and switch off when done.
I have a solar panel but it is pretty much useless at this time of year or possibly past it, I plan to meter it tomorrow.

Check out the Battery-Master.

https://www.vanbitz.com/the-van-bitz-battery-master/

As Paul says check out the battery master, it’s easy to fit and works just great, i have had one on both vans and and never had problems,  there is also the CSB2 unit that does a similar job but there have been reports of a few of these malfunctioning.

mcalid wrote:We have a Nuevo 2008 with the MES control panel. I am spending my life charging the batteries, both vehicle and leisure and it doesn't help that I have to manually switch from one to the other on the control panel when they need charged.
Can anyone tell me if there is some gizmo that I can buy which will allow me to leave the van on hookup and it will direct charge to the batteries as they need it and switch off when done.
I have a solar panel but it is pretty much useless at this time of year or possibly past it, I plan to meter it tomorrow.

Are you continually having to charge the batteries whilst the van is in use or out of use?  If the latter it suggests there is a drain on the batteries which needs to be identified and then turned off.

Caraman wrote:

mcalid wrote:We have a Nuevo 2008 with the MES control panel. I am spending my life charging the batteries, both vehicle and leisure and it doesn't help that I have to manually switch from one to the other on the control panel when they need charged.
Can anyone tell me if there is some gizmo that I can buy which will allow me to leave the van on hookup and it will direct charge to the batteries as they need it and switch off when done.
I have a solar panel but it is pretty much useless at this time of year or possibly past it, I plan to meter it tomorrow.

Are you continually having to charge the batteries whilst the van is in use or out of use?  If the latter it suggests there is a drain on the batteries which needs to be identified and then turned off.

You are probably right  Caraman but whatever it is l can’t find it.

You might want to read my recent posts on this thread:

https://www.autosleeper-ownersforum.com/t40526-dual-battery-solar-controllers#365864

If you replace your solar controller with a dual battery Votronic DuoDig MPPT controller, it will provide a trickle charge to the VB a) if there is sufficient daylight or b) if your mains charger is charging the LB.  This trickle charge should be sufficient to keep your VB charged.  The secondary benefit is that the Votronic's MPPT technology may harvest up to 30% more power from your solar panel if your current solar controller uses older PWM technology.  This will reduce your EHU dependency.   

https://www.roadpro.co.uk/product/12c01-12v-votronic-solar-regulators/votronic-mpp165-12v-dual-regulator-c55871/C55871

Caraman wrote:You might want to read my recent posts on this thread:

https://www.autosleeper-ownersforum.com/t40526-dual-battery-solar-controllers#365864

If you replace your solar controller with a dual battery Votronic DuoDig MPPT controller, it will provide a trickle charge to the VB a) if there is sufficient daylight or b) if your mains charger is charging the LB.  This trickle charge should be sufficient to keep your VB charged.  The secondary benefit is that the Votronic's MPPT technology may harvest up to 30% more power from your solar panel if your current solar controller uses older PWM technology.  This will reduce your EHU dependency.   

https://www.roadpro.co.uk/product/12c01-12v-votronic-solar-regulators/votronic-mpp165-12v-dual-regulator-c55871/C55871

I like that this unit will send charge to the vehicle battery when on EHU and this is exactly what I would like according to your description.
I hope that it is easy enough to fit, I am quite handy but no expert and thanks for your replies, really valuable.
One more question.
I see from the picture of the unit that there seems to be only one battery connection next to the solar panel input, I would assume that both batteries share this same connection?

It's very easy to fit.  It should be as close to the LB as possible.  2 wires in from the solar panel.  2 wires out to the LB with the positive fused close to the battery.  1 wire out to the positive of the VB with a fuse close to the battery.  Full instructions here:

https://www.votronic.de/index.php/en/products2/solar-technology/charging-controllers/standard-version-mpp/mpp-165-duo-dig#downloads

Quite a few Forum members have fitted this controller.

No changes need to be made to your mains charger wiring.

Caraman wrote:It's very easy to fit.  It should be as close to the LB as possible.  2 wires in from the solar panel.  2 wires out to the LB with the positive fused close to the battery.  1 wire out to the positive of the VB with a fuse close to the battery.  Full instructions here:

https://www.votronic.de/index.php/en/products2/solar-technology/charging-controllers/standard-version-mpp/mpp-165-duo-dig#downloads

Quite a few Forum members have fitted this controller.

No changes need to be made to your mains charger wiring.

I'm trying your patience here Caraman and I can follow most of it but please confirm that the wire to the VB comes from the small battery symbol to the right of the output to the LB.
Thank you for your expertise I am going to buy one of these.

Before you buy this ,what size solar panel and what regulator do you have fitted at the moment, if you do fit one of these you are best bypassing the Mes equipment completely, have you any intentions of increasing the solar panels you have now, 

This regulator will not rectify the problem that you asked about , you would still be best fitting the battery master for this

mcalid - correct.  The first smaller connection to the right of the four larger ones goes to the VB positive.  The connection is smaller as it uses smaller wire with a smaller fuse.  Unlike the feed to the LB, the feed to the VB is capped at 1A.  This is why it's smaller.  The other smaller connections are optional and are for a temperature sensor for the VB and a feed to the fridge if you have a fridge that will sense it.  I don't have these.  The negative to the VB is shared with the larger negative to the LB so no need to fit an extra one.

As Chris has said, it's worth checking what regulator you have now.  I have assumed its for a single battery and PWM.  The solar panel size is also important.  165 Votronic will handle solar panel inputs up to 165W.  If your panels are larger than this or you intend to fit larger ones you may need the 250 version of the Votronic which has a higher rating and I believe has a cooling fan.

I am unfamiliar with your Mes equipment.  Mine has a sophisticated EC700 power control system with an EC700 touch sensitive Control Panel.    I bypassed this by disconnecting the original single battery PWM regulator and connecting the new regulator directly to the batteries which is what others have done.

I don't follow Chris' last point.  The Votronic will do what the Battery Master does and more.  It supplies a trickle charge to the VB from the mains charge going to the LB and from the solar charge if there is no mains charge.  That was the point of my other thread.

Caraman what you are saying can not happen, if you have the regulator wired directly to the batteries bypassing your EC700, How have you wired the regulator to the mains battery charger?

The battery master will keep the starter battery charged even if there is no solar power ,
From the battery master info page

It is also fair to assume in this day and age that when you buy a sophisticated motorcaravan that has a built-in charging system for the leisure battery, this will also take care of the engine battery. However, the sad fact is that most converters do not make any provision for this. The main reason that the charging system in the motorhome is not wired to charge the engine battery is the serious risk of damaging the electrical components in the engine. This is why it is common knowledge that you must disconnect the engine battery terminals before attempting to charge the battery.
Battery Master completely eliminates this problem by electronically taking excess current from the leisure battery filtering out anything nasty and regulating the charging current to an acceptable 1.1amp.
Question: Will Battery Master work with a solar panel?
Answer: Yes, most certainly. It could have been made for it. As the solar panel increases the voltage in the leisure battery, so the excess charge is stored away in the engine battery.
Question: Will it work the other way and flatten the engine battery?
Answer: An emphatic NO! Battery Master will only take power from the leisure battery, never the other way around.
Question: Will it work without a mains hook-up?
Answer: Yes. It is designed so that when the engine battery drops half a volt below the leisure battery, Battery Master automatically adjusts the charge and tops up the engine battery.
Question: Does this mean that I could leave my van for longer in the winter without the fear of a flat engine battery?
Answer: Yes.
Question: Is it easy to fit?
Answer: Anyone who understands basic 12-volt circuitry can fit it. For those who prefer to have it installed, Van Bitz charges £130.00 to supply and install the Battery Master.
Question: I have seen cheaper things on the market, do they do the same job?
Answer: Ultimately yes, in the same way, that a tent does the same job as a luxury motorhome! In that, it is the style, safety and convenience that makes the difference.
Don’t forget – Even when you are using mains hook-up on a site, using your radio, cab lights, cigar lighter for charging, telephones, tablets, notebooks etc can create a great demand on the engine battery. With the Van Bitz Battery Master, this is not a problem. As you use power from the engine battery, Battery Master identifies this and automatically shunts power back into the engine battery to top it back up:
Once installed, it is completely automatic in operation. The only maintenance required is an occasional check to ensure that none of the cables are chafing or being damaged by heat.

Chris,

The Votronic is wired correctly and yes it bypasses the EC700 with the outputs going directly to the batteries.  The original PWM controller is unplugged from the EC700 and removed.  The Votronic sits in its place and has nothing to do with the EC700 which when the van is out of use, which is most of the time, is shutdown.  When the EC700 is not shutdown, no solar charge is shown on the EC700 CP which is correct.  I have not wired the Votronic to the mains charger.  I have not altered the mains charger in any way. However, when the mains charger is switched on and charging the LB, its voltage can be seen by the Votronic as the Votronic is connected to the LB.  The VB trickle charge voltage tracks the LB charge voltage and is always about 0.5V below the LB charge voltage which again is correct.  I like you was surprised that the VB voltage rose to 13.1V when the LB was being charged at 13.6V by the mains charger at night with no solar charge.  It's no use saying it can't happen because it does happen.  Test it for yourself tonight after the batteries have dropped to a resting voltage and there is no solar charge.  The EC700 and EC500 don't have to be on for the mains charger to charge the LB.  What I haven't done is measure the charging current flowing into the VB.  To do that test I would have to discharge the VB so that it needs a charge, which I don't want to do, and faff about in the dark and cold with my ammeter.  Maybe someone else wants to try that. I also haven't measured the VB solar charging current.  I have just assumed its 1A or less.  It certainly keeps the VB charged.

I know little about the Van Blitz Battery Master.  I thought it only sent a trickle charge to the VB from the mains charger.  If it does the same with a solar charge to the LB, then in this respect it seems similar to the Votronic.  With Votronic, when there is no charge going to the LB (solar or mains) or load, both batteries drop to their resting voltages which on my van are roughly the same.  I don't know if the LB would try and charge the VB if the latter dropped to say 11V.  This is not something I want to try!

If you replace your solar controller with a dual battery Votronic DuoDig MPPT controller, it will provide a trickle charge to the VB a) if there is sufficient daylight or b) if your mains charger is charging the LB.  This trickle charge should be sufficient to keep your VB charged.  The secondary benefit is that the Votronic's MPPT technology may harvest up to 30% more power from your solar panel if your current solar controller uses older PWM technology. 

I have read the instruction for the Voltronic and no where can I find it will act as you say in you post quoted

Sorry but you have totally lost me

FreelanderUK wrote:

If you replace your solar controller with a dual battery Votronic DuoDig MPPT controller, it will provide a trickle charge to the VB a) if there is sufficient daylight or b) if your mains charger is charging the LB.  This trickle charge should be sufficient to keep your VB charged.  The secondary benefit is that the Votronic's MPPT technology may harvest up to 30% more power from your solar panel if your current solar controller uses older PWM technology. 

I have read the instruction for the Voltronic and no where can I find it will act as you say in you post quoted

Sorry but you have totally lost me

 Test it!

Caraman wrote:

FreelanderUK wrote:

If you replace your solar controller with a dual battery Votronic DuoDig MPPT controller, it will provide a trickle charge to the VB a) if there is sufficient daylight or b) if your mains charger is charging the LB.  This trickle charge should be sufficient to keep your VB charged.  The secondary benefit is that the Votronic's MPPT technology may harvest up to 30% more power from your solar panel if your current solar controller uses older PWM technology. 

I have read the instruction for the Voltronic and no where can I find it will act as you say in you post quoted

Sorry but you have totally lost me

 Test it!

I can not test it as I only use Victron equipment and have enough solar that I don’t need to connect to the EHU to keep my batteries charged , what I will try though is if the charger is active when connected but nothing turned on 

FreelanderUK wrote:

Caraman wrote:

FreelanderUK wrote:

I have read the instruction for the Voltronic and no where can I find it will act as you say in you post quoted

Sorry but you have totally lost me

 Test it!

I can not test it as I only use Victron equipment and have enough solar that I don’t need to connect to the EHU to keep my batteries charged , what I will try though is if the charger is active when connected but nothing turned on 

Understood.  My controller observation only applies to the Votronic DuoDig MPP.  If you have an EC500, the PX300 will charge the LB if the EC500 is shutdown.  This has been documented elsewhere on the Forum.  If I think my LB needs a mains charge when the van is out of use, I don't turn the EC700 back on.  I have an electric levelling system powered by the LB.  When I get home I shutdown the EC700, connect to my EHU and turn the PX300 on so its charging the LB.  I then use the leveller to get the wheels off the ground.  I leave the PX300 on for an hour or so to ensure the LB is fully charged before turning it off.  I don't really need to do this as the solar charge should recharge the LB but perhaps not in the winter.  The EC700 remains shutdown until I am ready to use the van again.

Sorry I had a blonde moment there, the charger does charge with everything turned off 

I have now lost the will to live!!!

mcalid wrote:I have now lost the will to live!!!

You will often get conflicting views or advice on this Forum and some will be right and some will be wrong but often it will not be authoritative.  For that you need to go to the manufacturer or supplier and even then the person you end up speaking to is not always right.  A couple of weeks ago I would not have suggested the Votronic DuoDig as a solution to your problem because I didn't know then that it trickle charged the VB from the mains charge going to the LB, just as it trickle charges the VB from the solar charge going to the LB.  It appears that the Van Blitz Battery Master does the same thing but it won't improve your solar charging capability.  The choice is yours.

Fit a battery master and your problem is solved, the battery master will keep the starter battery charged with oot solar or EHU, it is designed to trickle charge the starter battery when ever the volts drop .5v below the Habitation battery voltage.

With poor solar that you get in the winter and you been on EHUjust leave your charge on the the habitation battery and let the battery master take care of the starter.

You will also benifit in the summer when solar is producing 

Sorry for all the off topic but this is a simple fit and forget item that does what you require

Here is something else you could look at but it won't improve your solar charge:

https://www.roadpro.co.uk/product/02e02-battery-maintainers/votronic-battery-master-c8451/C8451

I have a slight reservation about the 3amp Votronics battery-master in that it isn't smart. I'd say that Votronic simply overcame this shortcoming by reducing the charge voltage to the VB by 0.7V.
I suppose that's what Votronic have done with their Duo Dig solar controllers, reduce the voltage of the trickle charge going to the VB by 0.5V

Looking at the data sheet of the Morning star PWM solar controller that I fitted in our previous motorhome, it offered more. There were dip switches for each battery to set their individual charge profiles, and I could also set the ratio of the solar charge going between the batteries, to 90-10 or 50-50%.

I've become more reticent in offering advice the more I've realised how much A-S can change what's in a van, this works both ways, others may not appreciate the specifics of the problem you're having.
Glyne and I both have 2019 Kemerton XLs, he's got a Sargent EC500 system, mine an f**ing EC700 which came with the bonus of production faults, it cost us £££, miles of travelling and nights away. We're on our 3rd EC700 panel with a version of sofware that doesn't crash the system, some had 5 panels fitted.

I won't proffer any advice on which battery master is best as I knew nothing of them until this thread started.  But what this thread has done is given me an understanding of how my Votronic DuoDig solar controller might work.  I think it is a MPPT solar controller for the LB plus a battery master for the VB that gets its trickle charge from the LB no matter how the LB is being charged.    I have asked Votronic the question.  I'll see if I get a reply.  I wonder if the EPEVER Duoracer that Glyn Lock has (or Photonic Universe equivalent) is the same.  The only other MPPT dual battery solar controller I'm aware of is the NDS Sun Control 2.  It charges one battery at a time and chooses which battery it's going to be.  In this respect it's a bit like Sargent's Smart charging.  So it doesn't have any battery master characteristics.