You are logged in as a guest. 
  Home Forums Home  Search our Forums Search our Forums    Log in to the Forums Log in to the Forums  register Register on the Forums  

 Forums ->  Motorhomes -> Motorhome Matters
Jump to page : FirstPrevious 1 2 3 4 5 Last
Format:  Go
Yet another battery question
AuthorMessage
userspirou
Posted: 10 September 2018 5:35 PM
Subject: RE: Yet another battery question
 


Lives on the forums

Posts: 599
500252525
Location: SI, PVC X290 Peugeot


Was just thinking about LiFePO lately but from a slightly different point of view as before.

With more manuacturers fitting lithium as standard (or option) on new MHs, and quite a lot of people trading their rides every few years, the batteries will become a very nice subsidy to the next owner as I doubt anyone will pay ~1000 €/£ extra on a used van because of the battery. Unless you are very good at sales or taking the battery with you to the next one

There's also the uncertainty of what you're getting with a used van now including an unknown state of a very expensive battery. You probably won't change it just to be on the safe side.

And in case the batteries really live up to their claimed lifetime of several 1000 cycles, they could realistically outlive the life of the base vehicle.

Just some thoughts...
userspirou
Posted: 12 September 2018 8:52 PM
Subject: RE: Yet another battery question
 


Lives on the forums

Posts: 599
500252525
Location: SI, PVC X290 Peugeot


So I went to the show today, digging through lockers of every van I found. There were Adria/Sunliving, Carthago (no vans obviously), Hymer and a bunch of smaller local PVC converters. This was not a MH show, just side event, so not too much to see.

All of them had compressor fridges of various sizes/ brands and Schaudt 208 EBL. Most of them placed it under driver seat with the leisure battery under passenger seat, and a few with everything in the back left corner under the bed. Where fitted, there was Schaudt LRM solar regulator. The worst case was one company that obviously just started with their own PVCs and that one had 2,5mm2 cables everywhere (even where wiring instructions clearly say 6mm2) and a 100Ah Varta AGM battery right next to a truma combi heater. No wall or anything between them, nice and toasty. Oh, and a big compressor fridge. But that's OK, it had a 150W panel on the roof The guy I talked to had no idea what I was trying to explain to him about temperature impact on battery life and voltage drop over small cross section, long wires. He just went back to: "Varta AGM is great stuff, 800 cycles..."

I prodded anyone on staff that cared to talk to me why all the compressor fridges when they have tiny 70-100Ah batteries, some not even a solar panel. None seemed to believe it might be an issue. The reason most often given was the lesser impact of outside temperature on cooling. Obviously then, a majority of owners never go off EHU and they couldn't stand having their beer slightly less cold.

I only dug into the PVCs because I have an idea of where to look, I was completely lost in the Carthagos and Adria Sonics. Also didn't look into the Adria & Hobby caravans, Tischer "backpacks" or VW California vans that were around.

I was occasionally eavesdropping on other people looking inside and none had any technical questions. They were looking exclusively at the furniture. Someone even asked and couldn't understand why I'm more interested in whatever is under the bed, than the bed itself

In the end, an interesting experience and a lesson. The more expensive the MH, the harder it is to find the equipment that runs it. And even when you find it, access is severely limited.
useraandncaravan
Posted: 12 September 2018 11:10 PM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


Spirou, That was good timing as this morning, Dave brought back his Rapido that wouldn't achieve more than a 13.8v Alternator charge at the Platinum AGM Leisure battery.
It was back for surgery to have the AGM removed, two Varta LFD90 wet batteries installed and minor changes to the wiring to try and improve the charge rate on Alternator.

There was no room below the floor at the rear to add the second battery plus the battery was so far back it must have been having a significant effect on the rear axle loading. It was therefore decided to use the existing battery compartment as a 'Safe' and install two new batteries as far forward as possible below the bed, just above the axle and literally right in front of the CBE units.

You can see from the photos just how much excess wiring we removed, probably about 3 metres?.
This along with replacing the single AGM with 2 x Varta LFD90's, plus other minor changes, raised the Alternator charge at the habitation batteries from the previous 13.8v to 14.1v WITH the Fridge running on 12v.

Not perfect for wet batteries and still damaging for AGM's, but with the Varta's this would result in much faster and complete charging than before and more efficient Fridge operation.


While I altered the wiring, Dave, the owner, replaced the very inferior single battery solar regulator for a Votronic MPPT 165, which interestingly he got from Raodpro at around £80.


To allow the Votronic to charge both Habitation area battery and the Starter battery, I took a wiring tail from the Starter battery stud on the DS-xxx.

See the last photo (extracted from the web as I forgot to take one and while not the same as today's shows the position of the Starter battery stud in question).
This Stud is on the far right, Blue Cable, and if you were running a new cable directly from the Alternator, it is also this same stud you would wire to if you wished to minimise voltage drop further.





Edited by aandncaravan 2018-09-12 11:28 PM




(Rapido Rear battery 1 small.jpg)



(Rapido Rear battery 4 small.jpg)



(CBE DS 300 wiring small.jpg)



Attachments
----------------
Attachments Rapido Rear battery 1 small.jpg (48KB - 251 downloads)
Attachments Rapido Rear battery 4 small.jpg (59KB - 263 downloads)
Attachments CBE DS 300 wiring small.jpg (91KB - 740 downloads)
useraandncaravan
Posted: 14 September 2018 9:18 PM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


Very interesting customer today with a Swift motorhome purchased in Feb 2018 who has suffered three mains charger Sargent PX300 failures. All replaced under warranty, but with no explanation from the Dealer as to why they failed.

The owner had read this thread and asked if they could pay for an assessment like we offered Boris. So they came to see if we could identify the cause and high light any problems that might be at the root of the failures.

The Motorhome owner arrived yesterday at the Camp site we work from and stayed overnight. We had asked the owner to load up the 12v (without EHU) to simulate their usual 'Off grid' stopover. We then intended to simulate a short drive to a site for Water/Toilet emptying and then mains EHU to recharge the batteries.

We asked details about how the vehicle is used and then went through every thing on the vehicle.


The battery bank is made up of two Golf Buggy Yuasa REC80Ah-12 AGM batteries, not dissimilar to the single Golf buggy YU-POWER YPC100 battery fitted in Boris's vehicle reported above.

After a chat about the problems this morning, we first asked them to start the engine so we could check the Alternator charging voltages.

The Alternator charge voltage in 'driving mode' with the Fridge running from 12v was worse than usual. An abysmal 13.3v, we suspected because of the extra load that 2 AGM's impose, creating further voltage drop over the usual wet batteries 'half current load'.

We saw just 7 amps going into the batteries so the value of driving on Alternator was just about useless and exactly the kind of under charge that will fail an AGM prematurely.

The loading issue was confirmed when we cut the load by half by removing one of the AGM batteries and the charge voltage rose to 13.6v.

We then turned off the engine to connect EHU so we could monitor the PX300 charger at work.

I had expected the AGM batteries to suck the life out of the charger because they were down at 12.3v when we started the test, but what we saw over the next 2 hours even surprised me.
The charger ran so hot under the load,it was still flat out at the end of an hour.


If you go back to the very first Post by Aandy, you will note that the Wet battery charge rate of his Banners, reduced from 'flat out' down to 15amps after 5 minutes and further reduced to 8amps after 2 hours.
This poor poor charger was trying to put back close on 100Ah that had been taken out of the two batteries and the AGM's were demanding it 'NOW'.

These Golf Buggy AGM batteries were trying to draw about twice the normal current the PX300 is designed for and it was clearly struggling.
The PX300 is quite a few years old and the latest version has not had any upgrade to cope with AGM batteries.

We think that is why the owner is on his third Sargent PX300 charger, it just isn't designed to cope with the massive extra current load from an AGM battery bank.

However, the owner explained that when he took delivery he was told by the Dealer the batteries could be discharged down to 80%, and so he does, hence us seeing 12.3 at start of the test!!

When the Sargent PX300 load is doubled the load is going to be an issue on what isn't the strongest of designs.
But then to double it again by discharging below a normal wet batteries max 50% DOD, right down to the 'Dealers' assured 80%, has surely got to be a no hope situation?

To those who say, "a good muli stage charger should cope", I would ask them to show me a Good multi stage Motorhome charger. The Sargent PX300 is not a Victron.


It seems that Swift are now installing these AGM Golf buggy batteries as standard, but we need to do more research to confirm that.
Note that these batteries are not labelled up or described as Leisure batteries, which Sargent say in their manual are essential, but are -
"Commonly used in Alarm Systems, Golf Trolleys, wheelchairs, Emergency Lighting, Ride on Toys, Torches, UPS systems and other electrical systems".

If it is the case that they are standard Swift fitment, and not just random Dealer install, then Swift and Yuasa have not thought this through or learned anything from Hymers disastrous foray with AGM's 4 years ago.

Note that the standard fit Solar regulator was poor quality and not optimised for AGM's either.


It was a bit of a Eureka moment for me, as while I knew (and actually documented this behaviour above that AGM's had this effect) I had not witnessed it in such a controlled way or actually thought it back to a direct impact on the mains charger, yet that now seems obvious in hindsight.


We have documented what we found for the owner and advised him to go back to Swift with our findings to identify what they believe is the issue and solution, because sure as Eggs is Eggs, that third charger is on borrowed time and so are the batteries.



We would strongly suggest that any one with a Swift and these Golf Buggy AGM batteries does not discharge the AGM's more than about 25%, and ideally runs only a single AGM battery bank.

Alternatively look to a 30amp+ Victron Energy charger (try Roadpro) that IS optimised for AGM's (both Current and the right voltages AND the correct 13.2v storage float.
Also get remedial work done on the Alternator charging system, which is probably more crucial for most than the 230v mains charger.
Aim for an Alternator charge rate that is at least 14.3v, even better fully AGM optimised for both AGM1 and AGM2 charge profiles.


It is something Swift should have sorted before moving to AGM batteries, so maybe try and get them to put things right?


When Hymer and Banner did exactly the same thing 4 years ago, they initially fobbed off customers with "they will be fine on a Gel setting".
They weren't, the batteries failed prematurely and it cost them thousands in rushing through AGM optimised chargers.
Only in the last year have Hymer addressed the Alternator charge problem, which to be fair was at least close to 14.4v, not the awful 13.3v we saw today with discharged batteries and Fridge on 12v.

However, we now know that the much hyped at the time Hynmer/Banner AGM batteries, never were suitable for the application anyway, just as we reported back then.


Now that everyone is moving to the more appropriate EFB technology, maybe the easiest/best solution for Swift motorhome owners is to put in real Leisure batteries and sell the Swift ones on eBay?




Edited by aandncaravan 2018-09-14 9:33 PM
userspirou
Posted: 15 September 2018 6:49 AM
Subject: RE: Yet another battery question
 


Lives on the forums

Posts: 599
500252525
Location: SI, PVC X290 Peugeot


Just checking, have you ever had contact with motorhome manufacturers and their electrical departments? Educating the public seems a much harder job than the 100 or so companies. Although they are unlikely to change unless demanded by customers (extra cost and such) it still seems, by my limited contacts with various small van converters, that they aren't any wiser than their customers and have no idea why whatever they did is not correct. The dealers are probably even worse because they only care about selling and money.
useraandncaravan
Posted: 15 September 2018 8:15 AM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


spirou - 2018-09-15 6:49 AM

Just checking, have you ever had contact with motorhome manufacturers and their electrical departments? Educating the public seems a much harder job than the 100 or so companies. Although they are unlikely to change unless demanded by customers (extra cost and such) it still seems, by my limited contacts with various small van converters, that they aren't any wiser than their customers and have no idea why whatever they did is not correct. The dealers are probably even worse because they only care about selling and money.




Spirou, No real contact with any manufacturers and with my Oncologist saying I only have months left, it's not a challenge I want to take on.
BUT if anyone out there has any influence we would love to see :

1. Fiat/Renault/Citroen/Ford, etc fitting a new Fat (minimum 40mm/300amps) Earth strap (Grey Colour) from the Alternator body to Chassis then onto the Starter Battery Negative.
This will not only provide a first class, low voltage drop path for charging, but also address almost all the existing Earth issues suffered by most vehicles and often the cause of low charging volts on many 5+ year old vehicles.

2. An Orange Alternator B+ Feed (minimum 40mm/300amps) to the Starter Battery with two dedicated 'take off' points for Motorhome converters. One fused at 200amps for Habitation area battery charging and a 25amp dedicated take off for the Fridge supply.
An Alternator D+ trigger point in the same location would also make it easy for Converters and get rid of the need for VSR's.


I would like to see Orange become the new standard colour used by Converters/Motorhome builders for Alternator charging and the Fridge feed cable colour in Yellow with Green Stripes. D+ in Yellow.


Motorhome Converters should then use a minimum 35mm for all Positive and Negative cabling from Starter Battery to Habitation battery cabling with decent sized connectors through Power Control/Charger assemblies.
Many of the existing Power controller/Charger units use Copper PCB Tracks and connectors that, even if the cable was adequate, are far too low rated. They are often rated solely on the current they have to pass, not voltage drop.


And while I am at it, I would love for the UK to adopt the safer Continental practice of keeping 230v and 12v separate, not put both the RCD/230v and 12v distribution in the same cabinet.
Maybe 230v enclosures in Motorhomes/Caravans to be Plastic, not metal.



Edited by aandncaravan 2018-09-15 8:31 AM
userKeithl
Posted: 15 September 2018 9:49 AM
Subject: RE: Yet another battery question
 


Lord of the posts

Posts: 5673
50005001002525
Location: Birmingham. 2004 Auto-Trail Cheyenne Mercedes 313.


aandncaravan - 2018-09-15 8:15 AM

2. An Alternator B+ Feed (minimum 40mm/300amps) to the Starter Battery with two dedicated 'take off' points for Motorhome converters. One fused at 200amps for Habitation area battery charging and a 25amp dedicated take off for the Fridge supply.
An Alternator D+ trigger point in the same location would also make it easy for Converters and get rid of the need for VSR's.



Mercedes almost do this in that they offer an option called "EK1 TERMINAL STRIP FOR ELECTRICAL CONNECTION" which includes three terminals for body builders to connect to. I'll attach a photo of a 2007 on.

aandncaravan - 2018-09-15 8:15 AM

2. An Orange Alternator B+ Feed (

I would like to see Orange become the new standard colour used by Converters/Motorhome builders for Alternator charging and the Fridge feed cable colour in Yellow with Green Stripes. D+ in Yellow.



Allan, the only problem here is that Orange is the standard colour for HV cables on Hybrids and Electric vehicles so could cause confusion with emergency services and the like.I would suggest you find an alternative colour or some means of identification.

Keith.



(NCV3 EK1 Terminals r.jpg)



Attachments
----------------
Attachments NCV3 EK1 Terminals r.jpg (88KB - 1041 downloads)
userspirou
Posted: 15 September 2018 1:20 PM
Subject: RE: Yet another battery question
 


Lives on the forums

Posts: 599
500252525
Location: SI, PVC X290 Peugeot


While on the subject... Where can I conveniently get D+ on an x250?
userDeneb
Posted: 15 September 2018 2:16 PM
Subject: RE: Yet another battery question
 
Pillar of the forums

Posts: 688
500100252525
Location: Vantage Sol PVC


If your van has the factory conversion socket 15 pin connector behind the offside B pillar, there is a connection point there. I am away from home at the moment, so don't have access to the relevant documents, but you will find the information in the X250 eLearn or Training manuals which are both online - searchable.

The D+ is a pull to earth connection, I think on pin 13 or 15. There is a positive ignition controlled supply I think on pin 2. Use a relay with the switched earth connected to the D+ trigger pin and the supply and switch positive both from pin 2. You will then have a 12v feed when the relay earth is switched by the D+ switched earth at the socket (pin 13 I think, but check first).

Terminals for the 15 pin "Mate N Lock" socket are available on eBay, as are the connector blocks if required, although my van came with the empty plug block sitting in the socket.
userveletron
Posted: 15 September 2018 6:06 PM
Subject: RE: Yet another battery question
 
A posting machine

Posts: 335
10010010025
Location: Stirling


Why do manufacturers run such poxy cable for battery charging? It should be clear from the outset that the voltage drop over that length of poxy cable would result in a poor user experience. I know its cost+payload, but really, £50K+ for such poor engineering? That cable should have been at least 4AWG and preferably 2AWG given the distance.

The same is true of fridge wiring. 14.4V at D+, ~12.5V at the element all due to running cable that cant cope with the 200W load without a huge voltage drop - all this leads to is a fridge that wont cool properly on 12V and thus a poor user experience for the sake of maybe £5 and under half a kilo for appropriate cabling!

My van was the same, I ended up re-wiring everything, but I shouldn't have to!

Nigel
useraandncaravan
Posted: 15 September 2018 8:04 PM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


spirou - 2018-09-15 1:20 PM

While on the subject... Where can I conveniently get D+ on an x250?


Spirou, I think you said you had a Schaudt Elektroblock EBL208 installed, if so you will find D+ at pin 22 which is set aside for technicians to use for driving the retraction of Satelite systems and such like.



Keith, Yes I like the Merc 'option' setup, but it is usually under the right hand seat, with the disadvantage of extra connectors and 'thin' cable and a longer run than straight from the Starter Battery.
The Merc option is not that different to the UK built vans that have a takeoff from the right hand dashboard down and across to the right hand door pillar.
But the cable run actually begins at the Starter Battery under the passenger feet on the left hand side, up to the Dash, along to the right hand dash side. Back down to the floor by the door Pillar, etc. Probably a wasted 2.5 metre cable run in 'thin' cable with about 5 different connectors?

To make it worse a UK Sargent Power Controller/charger often sits up high in an overhead cupboard, so the battery feed then runs back up from the base of the door pillar to the roof and then back down again to the batteries at ground level. You couldn't create a poorer design if you tried.


The best we have seen was a Burstner with the 12v electronics/power controller under the passenger seat just 2 feet from the starter battery with the habitation batteries under the Drivers seat, everything that is cable length critical was in close proximity.



I don't think the battery industry is aware just how bad some of these installations are or the impact they will have in destroying batteries that are not super tolerant of poor charging, etc.

One thing AGM's are not, is tolerant, but Wet acid batteries have a long history of proving that tolerance is one thing they have in spadefuls.


Edited by aandncaravan 2018-09-15 8:23 PM
userspirou
Posted: 15 September 2018 9:54 PM
Subject: RE: Yet another battery question
 


Lives on the forums

Posts: 599
500252525
Location: SI, PVC X290 Peugeot


That's just the thing... whoever did our van wiring was an idiot who couldn''t read the wiring diagrams supplied with the EBL208. He wired the "D+" pin from the starter battery (via VSR) which meant the EBL was nearly always drawing 0.4A in standby mode. We've since replaced it with a somewhat crude solution of wiring it off the rear light cluster. Since lights are on when the engine is running it works. But if I do get to work on rewiring the cables to leisure batteries and installing a B2B I would like to use a real D+ wherever it's needed.

Now that I think about it, I never checked how he wired the stairs to retract with ignition on.

The electrician in question got fired within months if not weeks. Our van was one of the few he worked on and I'm surprised he lasted as long as he did. When we took the van back a few times the new electricians did fix a few things but these were again just improvised solutions that didn't resolve the core issues. I've looked at several of their newer vans, also this week at the show, and I did notice improvements but still not as good as it could/should be. The conversations there prompted my question regarding educating companies rather than buyers. They simply didn't see any issues even when I pointed them out. Granted they probably weren't electricians but sales people however the designs and solutions suggest this is an industry wide lack of understanding.
useraandncaravan
Posted: 16 September 2018 8:00 AM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


Spirou, It is a wide spread issue across many vehicles from around the World, but some manufacturers pay more attention to detail than others.

While poor Alternator charging design will clearly have a major impact on the end result, this has come to a 'serious' head because a change in the loadings placed on those systems, which while not even vaguely efficient in many cases, have at least been safe while wet batteries are being used.

Fitting AGM batteries in motorhomes can be like installing an exploding bomb on a timer, literally, which I don't think many fully appreciate.

We have established the charging systems are worse than average on UK built motorhomes, so unsuitable for AGM batteries.
Veletron, for whom I have huge respect for his electrical and motorhome knowledge, yourself and many others have established that as fact.
By moving from Wet batteries that are super tolerant of any old Alternator charge rate above 13.5v to intolerant AGM batteries has introduced an element of danger that I think might be better not side tracked by manufacturers installs?

Now we have seemingly broad acceptance that the charging systems are severely flawed, may I now reiterate the danger aspect, because in all the replies, both on here and the Swift forum, it doesn't seem to have been acknowledged?


Why are AGM's more dangerous?
AGM batteries are from a group called Valve Regulated Lead Acid batteries where a valve is inserted into the 'Vent' at the top of the battery to keep them pressurised internally. One industrial AGM battery we are aware of has a vent pressure close to 30 PSI, but the norm is only a few PSI.
This raised internal pressure helps to recombine any Hydrogen/Oxygen back into water which then drips back into the battery cells.

It is universally acknowledged that AGM batteries are more prone to 'Thermal Runaway' explosion than any other Lead Acid battery type.
As the battery tires it runs hotter, this promotes battery breakdown, producing more heat. This extra heat promotes faster breakdown, that produces even more heat and faster breakdown again until, BOOM.
In some instances Fire is a greater risk.

So obvously an AGM battery in a Swift motorhome, which clearly won't get anything like the correct charging voltages/charging, is going to fail fairly quickly. But this won't be expected by the motorhome owner who 'knows' he has spent double the money on an "8 year life battery", so uses it well past it's safe best.

You can also see that if the battery breaks up internally debris can block the valve potentially making the explosion more serious. it is also obvious that if you install the battery on it's side or inverted, how debris will be more likely to block the valve increasing both the risk and consequences of the explosion?

We saw AGM battery explosions when Hymer/Banner rolled out AGM's in 2014, and that was on Alternator charging systems and chargers that HAD close on 14.4v, not the mid 13v we see in Swift built "AGM" motorhomes.




But they are safe in a Car, what's the difference?

Having an AGM battery in the boot of a car that is constantly monitored for temperature, capacity, efficiency, etc will have it's degraded nature reported by the ECU long before it is even 80% used. So it gets replaced well before risk of explosion.
Even if explosion occurs in a Car, the hazard to life is low as it is not in the passenger compartment.


Long term unattended, unmonitored use on EHU/Solar of an AGM battery that we KNOW will fail early in a motorhome is quite different.

Even if the risk of explosion was minuscule, is an exploding battery something you want under your seat?


One other question : are these Golf Buggy batteries low pressure VRLA's with just a few PSI or 30PSI style industrial batteries, as that may impact safety?



Spirou, you say above about fitting a B2B, which is the way most technicians address this issue, but do you realise that is 'bodge' not a fix?

What some B2B's do, like the old Sterling units is just raise the charging voltage at the habitation battery to a higher, preset output voltage. But increasing the voltage is done at the expense of less current. Additionally the units often run at about 85% efficiency, so you can see that this isn't the best option.

If you further add into the mix that the Fridge runs from the habitation area battery, it can still drop even the 'boosted' voltage.
Some newer B2B's will try and compensate for this voltage drop, but again at the expense of current.
The overall benefit from the average B2B, even those that some have spent thousands on, can be less than 75% so won't be as efficient as taking the Fridge feed direct from the Alternator/Starter battery and using proper sized cabling where good practice and common sense can yield 100% efficiency.

Like I wrote above in an earlier post,

"It is a shame they (B2B's) actually address the wrong issue, boosting the voltage when all that is needed is sensible Fridge cabling, wiring, etc. not a £600 expenditure. Another example of the products in the market place not understanding the issues?".


But now we are getting back to the hardware when I would rather inform on the danger for now.................







Edited by aandncaravan 2018-09-16 8:08 AM
userspirou
Posted: 16 September 2018 10:46 AM
Subject: RE: Yet another battery question
 


Lives on the forums

Posts: 599
500252525
Location: SI, PVC X290 Peugeot


Fully aware I'd be trading voltage for current but, as our consumption is quite low and the battery not very large, I'd be inclined to such trade in. When I measured the voltage at starter battery under alternator charging it wasn't much above 14V, highest I saw was 14.2, albeit at idle and after only about a minute.

So even if I upgrade cables to 6mm2 (reasonably largest I might be able to pull through) it still won't get me to 14.4 or so.
But, as I haven't really had a chance to explore the viability of these mods, I just might end up doing nothing. It's not entirely up to me anyway as the van belongs to my parents and I just use it whenever available. They are inclined towards improvements and we keep working on various bits (not many things left from original state) but if the electrics turn out to be too complicated to sort out they might just say it's good enough as it is.
useraandncaravan
Posted: 17 September 2018 10:00 AM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


Spirou, Almost 98% of the benefit of the usual Motorhome B2B install comes from the cabling that they dictate is used as part of the installation, not the B2B itself.
Just look at a Sterling B2B installation manual on the web and you can see that the minimum 16mm cabling they specify is going to make THE difference.

They also stipulate single cable runs, so losing the usual zillions of connectors that many motorhome builders/converters use.

While I would like Motorhome Builders to use much fatter cabling than 10mm in their installations, when improving existing ones, the cabling does not need to be as large because it's in addition to whats already there.
So just adding an additional 6mm (50amp) rated thin wall cabling with a decent Split charge relay will make a massive difference to your setup. Especially if you take both the Positive feed and Negative directly from the Alternator B+/Body.


The work involved is half the labour of fitting the usual Sterling B2B, with costs that are not quite in their 'pennies' but are low.
About £1.69 a metre for the cable (12v Planet) and less than £4 for our 'B2B equivalent' Split charge relay from several suppliers on ebay.

The Split charge relay is a key component, it should be rated to at least 100amps, not because it will pass that much current, but because the contacts will be huge so voltage drop across them will be low and more resistant to burning as they age.

See our web page for more info on how to do it yourself, how to diagnose issues, etc : http://www.aandncaravanservices.co.uk/add-a-second-battery.php
Look for the section at the bottom of the page titled, "Things You Might Want to Think About If Increasing The Battery Bank Size, Even Slightly", just above a picture of a Split Charge Relay.


You don't need to disable the existing arrangement, this will work in parallel with what you already have. Don't forget the 60A fuse.


Cable supplier :
https://www.12voltplanet.co.uk/50-amp-single-core-thin-wall-auto-cable.html

Split charger relay supplier £3.99 :
https://www.ebay.co.uk/itm/Car-Motor-Boat-Split-Charge-Relay-DC-12V-100A-ON-OFF-4-Pin-Heavy-Duty-New/151867130466?epid=601221192&hash=item235bfc8262:g:feAAAOSwFIVayblW

Note these are not recommended suppliers, just examples.


Edited by aandncaravan 2018-09-17 10:25 AM
userarthur49
Posted: 27 September 2018 10:50 PM
Subject: RE: Yet another battery question
 
Pillar of the forums

Posts: 702
500100100
Location: North - Wildax Europa on Renault Master 2.3 170bhp


aandncaravan - 2018-09-17 10:00 AM

See our web page for more info on how to do it yourself, how to diagnose issues, etc : http://www.aandncaravanservices.co.uk/add-a-second-battery.php
Look for the section at the bottom of the page titled, "Things You Might Want to Think About If Increasing The Battery Bank Size, Even Slightly", just above a picture of a Split Charge Relay.



Sorry for being 10 days late on this one, but as I said in a previous thread, I installed Allan's recommendation. DIY. I found it easy. With engine running and fridge off I'm getting 14,34v at leisure batteries
userarthur49
Posted: 4 October 2018 10:20 PM
Subject: RE: Yet another battery question
 
Pillar of the forums

Posts: 702
500100100
Location: North - Wildax Europa on Renault Master 2.3 170bhp


aandncaravan - 2018-09-17 10:00 AM

You don't need to disable the existing arrangement, this will work in parallel with what you already have. Don't forget the 60A fuse.


So sorry Allan for resurrecting this thread and your statement above - we've been away from home!

As I said in post above I've installed your wiring/split charge suggestion and achieved a big improvement in charging whilst engine running (14.34v at LBs, tick over, fridge off)

But I DID disable existing arrangement. I can see now there is no need to do that as 'existing' and 'improved' will simply complement each other. Or am I misunderstanding your statement above?

Thank you Allan
useraandncaravan
Posted: 4 October 2018 11:52 PM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


Arthur, it depends on what the set-up is already. The response above was specifically aimed at Spirou's vehicle, but generally, the improved 'new' cabling will effectively provide a 'wider' pipe through which the electricity will flow.
Just like Water through larger sized pipework, electricity will take the path of least resistance, through the thick, low voltage drop cable.

However, because the current in the old 'existing cable' is reduced, because a second cable is carrying much of the load, the voltage drop in the old cable is also less than it would have been. So even the old wiring delivers better overall power with a raised voltage as a result.

Reducing the current in a wire by half, has a similar effect (well nearly) to doubling the wires thickness in terms of voltage drop.
So just adding a second cable the same size can have a dramatic effect, making the new cable slightly thicker again to 6mm/50amp is better still.


That is one of the reasons why we like to use the existing split charge relay to drive the new 100+ amp relay.





Edited by aandncaravan 2018-10-04 11:57 PM
userarthur49
Posted: 5 October 2018 9:35 AM
Subject: RE: Yet another battery question
 
Pillar of the forums

Posts: 702
500100100
Location: North - Wildax Europa on Renault Master 2.3 170bhp


aandncaravan - 2018-10-04 11:52 PM

Arthur, it depends on what the set-up is already. The response above was specifically aimed at Spirou's vehicle, but generally, the improved 'new' cabling will effectively provide a 'wider' pipe through which the electricity will flow.
Just like Water through larger sized pipework, electricity will take the path of least resistance, through the thick, low voltage drop cable.

However, because the current in the old 'existing cable' is reduced, because a second cable is carrying much of the load, the voltage drop in the old cable is also less than it would have been. So even the old wiring delivers better overall power with a raised voltage as a result.

Reducing the current in a wire by half, has a similar effect (well nearly) to doubling the wires thickness in terms of voltage drop.
So just adding a second cable the same size can have a dramatic effect, making the new cable slightly thicker again to 6mm/50amp is better still.


That is one of the reasons why we like to use the existing split charge relay to drive the new 100+ amp relay.



Thanks Allan. I'm starting another thread about an article in C&MC magazine and I'll see if I can scan it and send it to you. All about L-ion, with some staggering statements eg 100Ah lead acid battery weighs about 35kg (25kg?) and costs about £300 (£110) .....
userEarthmover
Posted: 11 October 2018 10:27 PM
Subject: RE: Yet another battery question
 
Keeps coming back for more

Posts: 153
1002525


Hi Allan,
You mention a 40mm/30amps earth strap (Grey), where would I try get one from?. What size cable do you recommend for running from the chassis to the battery Negative. Can you do a sketch!. thankyou.

Regards Em.

Ps, thankyou for your comments on my wind turbine question. I have been trying to visualise the size of your Motorhome, which requires a wind turbine with 90ft blades!!.
userDerek Uzzell
Posted: 12 October 2018 9:23 AM
Subject: RE: Yet another battery question
 


50005000500020002000500100100252525
Location: MODERATOR - 2015 Rapido 640F LHD 2.3ltr 150bhp


This March 2018 discussion may help regarding the earth strap

https://forums.outandaboutlive.co.uk/forums/Motorhomes/Motorhome-Matters/Ducato-X250-2-3-Multijet-Earth-Strap/48885/

userspirou
Posted: 14 October 2018 3:17 PM
Subject: RE: Yet another battery question
 


Lives on the forums

Posts: 599
500252525
Location: SI, PVC X290 Peugeot


Did some more testing this weekend both on the road and at home. Results below are with the vehicle stationary. I'll save the driving results for another thread.

With the alternator (at idle speed) charging only the engine battery: 14.0-1V (lights on/off didn't make a difference)

With the existing 6mm2 wiring, fridge on max power, radio on: 13.7-8V (measured at leisure battery)

With additional 10 (maybe 16mm2, can't tell as there is no exposed core to measure) ancient jumper leads with tiny crocodile clips (so possibly not ideal conduction), fridge ON, radio ON: 13.8-9V

So I decided that I'll do some minor rewiring and use dual 6mm2 wires (already in place) which will aparently get me an improvement of 0.1V at best. Not much but as the work involved is not that difficult I'll do it anyway.

The second pair of wires that I will repurpose is currently used for the radio and I'll just wire it to the starter battery. We hardly ever use it without the engine on and it can be turned completely off so no phantom drain on engine battery. And it comes with the added bonus of saving 2-3A load from the leisure battery.

The question then becomes, what can be done to improve alternator charging further? I don't know if x250 2.2 EURO5 engine has a "smart" alternator or not. Probably not? Is B2B the only viable next step? That would probably be one of the Schaudt units to keep things in the family. I definitely won't go for the major job and do what weldted did.
useraandncaravan
Posted: 15 October 2018 10:06 AM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


Spirouu, Yes take the charging feed from the Alternator B+ and the Alternator body.
It can especially make a huge difference on a vehicle 4+ years old.

See our webpage : http://www.aandncaravanservices.co.uk/add-a-second-battery.php
See about 3/4 down the page starting from the image of the giant relay.


No, X250's don't have any sort of Alternator smart charging,not even the 2018 model/Euro6 we have just worked on. Just a fixed 14.4v output.
I suggest you should be focusing on resolving the wiring issue first. Fix that and you won't need a B2B.



Edited by aandncaravan 2018-10-15 10:16 AM
userfesspark
Posted: 17 October 2018 11:03 AM
Subject: RE: Yet another battery question
 


Pillar of the forums

Posts: 610
500100
Location: Holcombe Dawlish Devon


I have a 5 month old Burstner 680G only used it for 700 miles so far has a 150 w solar Panel fitted on roof that seems to be charging fine, How ever the Bty has stopped holding its charge. 2 questions as the bty is a Varta dry cell 95Ah 850A can I replace it Temporary with a Varta LFD 90Ah wet cell that I kept from my last Burstner fully charged and nearly new until I take it to the dealer on Warranty? I have connected it up and not put the fuses back yet. Fesspark
useraandncaravan
Posted: 17 October 2018 11:38 AM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


Fesspark, It is not abnormal for the AGM Varta to fail prematurely, so not surprised yours has also gone, see our web page on AGM batteries : http://www.aandncaravanservices.co.uk/agm-batteries.php

Yes the Varta LFD90 is the best option on that vehicle and will tolerate the Elektroblock EBL chargers higher AGM charge voltage of 14.7v quite well short term, but we recommend using the Lead/Gel setting on the EBL unit in the longer term..
Only change the switch setting with the mains disconnected. The slide switch is easily damaged so gently does it and use a Ball Point pen.


The Solar regulator must also be changed to a wet acid setting in the longer term, but ok short term, that is assuming it is the correct Schaudt LRM1218?.


Suggest you ask for a cheaper but more motorhome appropriate LFD90 or Yuasa L36-EFB under the warranty claim rather than get another AGM?.





Edited by aandncaravan 2018-10-17 11:43 AM
userspirou
Posted: 17 October 2018 1:18 PM
Subject: RE: Yet another battery question
 


Lives on the forums

Posts: 599
500252525
Location: SI, PVC X290 Peugeot


Just took a look at the installation instructions for EBL208 and their B2B WA 121525 and one thing stands out immediately. Whereas the EBL suggests use of 6mm2 cables between both batteries, the B2B has them at 16mm2 (10 possible). Quite a difference.

As I was thinking about it I might try to pull a bigger cable through rather than use doubled 6. Not sure if 2x16mm2 fits in the same space as 4x6 though. Have to go find some cable to measure first. I only find core diameters online.
userfesspark
Posted: 17 October 2018 1:38 PM
Subject: RE: Yet another battery question
 


Pillar of the forums

Posts: 610
500100
Location: Holcombe Dawlish Devon


Thanks Al,have put the 90Ah on the EBL setting as you suggest, not sure I need to alter the Solar reg? all seems well at the moment, put the 95 on electric Bty Charger for the day and I will disconnect later and see tomorrow if its held its Charge,feespark
userfesspark
Posted: 17 October 2018 5:45 PM
Subject: RE: Yet another battery question
 


Pillar of the forums

Posts: 610
500100
Location: Holcombe Dawlish Devon


Alan, just checked the battery in the m,home, My 90Ah was showing 13.5 ,V ie fully charged at 2 pm, now at 5.45, and getting dark, dropped to 12.5,by tomorrow I suspect it will be even lower, It looks as if something is draining the battery, the engine bty; is still good.Maybe its good news ,not the 95 gone but something within the m,home, any ideas what to do? fesspark
userspirou
Posted: 17 October 2018 6:35 PM
Subject: RE: Yet another battery question
 


Lives on the forums

Posts: 599
500252525
Location: SI, PVC X290 Peugeot


First I'd put the multimeter to current mode and see if there is actually any drain present. Then go through devices one by one (or fuses if available) to see if there's any change
useraandncaravan
Posted: 17 October 2018 6:38 PM
Subject: RE: Yet another battery question
 
Forum master

Posts: 2265
20001001002525
Location: Conwy, North Wales


13.5v at 2 pm is not the battery voltage, but the voltage at the battery raised by the Solar charger. The actual battery voltage might have been only 12.4v.
It can't have been 13.5v because an LFD90 has maximum 13v.


I think you need to put the LFD 90 on EHU for 24 hours to be sure it is fully charged??

When you then check the SOC, the battery needs to have been off charge and off load for a few hours.

Edited by aandncaravan 2018-10-17 6:41 PM
Jump to page : FirstPrevious 1 2 3 4 5 Last
Printer friendly version
E-mail a link to this thread
Jump to forum :


(Delete all cookies set by this site)(Return to Homepage)

Any problems? Contact the administrator