Yet another battery question

[aandy]

aandncaravan - 2018-09-02 7:16 PM

 

aandy - 2018-09-02 6:51 PM

 

Thanks Allan. Evidently I was expecting too much of them, so perhaps replacement is not as imminent as I had thought. While I can guestimate the usage on things like TV and lights, high consumption in short bursts items such as water pump and cooker and boiler fans are probably where my calculations fall down.

 

Andy

 

Andy, Only reliable way we have found to test a Motorhome battery, is listed at the bottom of this web page :

http://www.aandncaravanservices.co.uk/battery-technology.php

 

If a battery has been 'exhausted' yet has no faults in the plates, i.e no shorts, no sulphation, etc. it can hold a steady voltage for weeks, yet not have any real capacity.

 

 

 

 

That's pretty much what I did a couple of weeks back. Resting voltage dropped by 0.4 after taking around 60 amps so, with 60-70% of their nominal capacity remaining, the batteries would appear to be knackered. From what you've said about my charging regime it may be that they were not fully charged at the start of the test, but as I've been doing it that way for some time that in itself has probably damaged them.

 

I have no problem replacing anything that needs replacing, but really hate waste and was reluctant to dump them until I was sure they were past it. I'll be replacing them with EFBs, so as I invariably use EHU in winter I can hang on to them until the spring, by which time, hopefully, EFBs will be more readily available.

 

Andy

[spirou]

Everyone gets grumpy, most others without a proper excuse so don't appologize.

 

Lets for example say I'd want to add a victron bluesmart charger on top of the schaudt EBL and I want to keep all the existing functionality of the EBL, except ability to charge the battery on EHU. I just don't see if that would work, at least not without manual switching between units? Which wouldn't work for other family members, it would need to be failsafe. Or would it be as easy as just unplugging the 230V input to schaudt and hooking it up to victron? I suspect the 230V sockets around the van don't go through the EBL?

 

All just academic thought experiment, not considering it in reality.

[aandncaravan]

spirou - 2018-09-02 9:29 PM

 

Lets for example say I'd want to add a victron bluesmart charger on top of the schaudt EBL and I want to keep all the existing functionality of the EBL, except ability to charge the battery on EHU. I just don't see if that would work, at least not without manual switching between units? Which wouldn't work for other family members, it would need to be failsafe. Or would it be as easy as just unplugging the 230V input to schaudt and hooking it up to victron?

 

All just academic thought experiment, not considering it in reality.

 

 

Spirou, Yes that is exactly what happens and Schaudt provide the kit for it.

 

The Schaudt LAS1218 auxillary charger below is designed as an 'Add on' to the Schaudt Elektroblock range and is designed to be utilised if the battery bank is raised above a single 90Ah battery.

It is this unit that is the bulk of the cost for the 380€ cost of a second battery that Hymer charge if you specify that option.

But because the Dealers fit the second battery they rarely fit the second charger.

 

It comes with a full cable set to plug into an EBL 208 like your or any EBL 99, etc. but if you don't have a cable set, then make one up, which is what I suggested to Arthur, that allows you to switch manually by controlling the 230v into the chargers.

 

If you look closely at the UK spec 13a/230v adapter in the second photo (it may not a be familiar in Solvenia so might seem a bit 'odd') that I suggested Arthur make up, you will see it has multiple 230v outlets, but it turns the usual 230v feed into the front of an EBL 208/EBL99 into a multiple feed for 2 chargers.

 

The second photo below shows one of these 230v Spike/Surge adapters (a sort of OVP01 equivalent) with multiple switches so you can power all or none, etc.

 

In the case of the standard EBL 208 and LAS128 working together, they do it just perfectly and continuously reducing charge times and loadings.

 

Using two very different technology chargers can be an issue, but just think about your vehicle. It has Alternator and Solar at the same time, Mains and Solar at the same time, etc

 

 

A Schaudt EBL 208 and a Victron coupled into the EBL 208 front 2 pin charger port, just for this purpose, would work really well. When you want to de-activate the EBL 208 inbuilt charger, so the Victron can control 13.2v float, just turn off its 230v at the Spike/Adapter.

 

The EBL doesn't control 230v power, that is done via a separate RCD, keeping them separate is safer.

One thing I don't understand In the UK we get paranoid about reverse polarity but then put 12v AND 230v distribution wiring all in the same metal Power controller/charger cabinet.

 

 

[arthur49]

spirou - 2018-09-02 8:25 PM

While doing the test today I tried, but couldn't figure out an easy way to upgrade to heavier wiring and that's not even my first priority on the list of things to fix. Batteries at opposing ends of the van pretty much include ripping out some furniture and trim, or wires stuck somewhere midway as you try to pull them through.

 

I'm no expert but to beef up wiring in accordance with Allan's recommendation I found to be a piece of cake. The worst bit was lying flat under the van getting the 25sqmm wiring from front to back (starter to hab battery), because my blood pressure meds make me light headed when I try to get up 8-) 8-) 8-) . No need to rip out furniture etc. Just out through the floor - I used a pre-existing large vent - then in through the plastic box in which the starter battery sits (and convoluted conduit for external wiring)

I did have to figure out a way to disable EC155 split charge relay but that wasn't too difficult

[aandncaravan]

spirou - 2018-09-02 8:25 PM

 

 

I've noticed that thread with starter battery inverter as pseudo EHU before but haven't really looked into it. At first look seems quite an undertaking to make that conversion if you don't plan for it in the first place.

 

 

People add Inverters to the habitation area battery all the time to power a hair dryer, etc. easy to do.

Bad idea to use the habitation area battery, in my view, but easy.

 

In it's basic form, Weldteds idea is just a small Inverter connected to the STARTER battery driving the Fridge and mains charger, that is it.

 

Imagine fitting an Inverter to the Starter battery then run the Inverter 230v output cable to a new 'Inverter only' powered 13a socket (or maybe Schuko socket in your case?) next to the Fridge which you use for the Fridge when driving.

Just pull the Fridge mains plug from the 'EHU' socket and plug into the 'Inverter socket' before you start your journey.

 

What could be simpler?

 

Same for the mains charger 230v input.

 

 

My 'better way' of running the 'Starter Inverter' 230v output direct to the RCD using 16amp EHU style male female connectors allows all 230v circuits in the vehicle to run from the small Inverter and powered by the engine as an efficient emergency 'generator', that will actually get some decent charge into the battery.

 

That is all it is. It doesn't alter any 12v control charging, introduce maintenance issues, battery overcharging, or any of the usual problems caused by a B2B installation that can affect long term reliability.

 

 

It is an especially brilliant, cheap mod for those with a Camper van using those Amp Hour guzzling 12v Compressor Fridge's.

With a good charger and battery set-up, just 25 mins engine run time can not only get a Waeco Coolmatic 65 down to 'Cold' but put in decent emergency charge into the battery, even in mid winter when Solar doesn't provide any usable power.

 

For more on this specific problem with 12v compressor Fridges, and how to improve their usability, see the new web page (still under construction) : http://www.aandncaravanservices.co.uk/compressor-fridge-12v.php

 

 

 

Spirou and Arthur, there is so much good stuff in this thread, please can I use it on the web site?

 

You can dictate content, full control.

 

 

[spirou]

Use whatever you wish. I can also supply the raw data logs (CSV) if you want to work on them yourself. My quick annotations could definitely use some work to clarify a few things. Not sure how people understood the different logging intervals, probably better to word it as duration of that particular segment.

 

So... if you'd like to use the charts, I really want to fix a few things :-D

[arthur49]

aandncaravan - 2018-09-03 7:40 AM

 

Spirou and Arthur, there is so much good stuff in this thread, please can I use it on the web site?

 

You can dictate content, full control.

 

 

Use anything you want Allan. All the best ....

[spirou]

One comment regarding the compressor fridge page... the thing people seem to forget is that you have to park in the sun to get the most out of a solar panel. But parking in the sun, in temperatures above ~25°C will be a nightmare to anyone inside the MH. Not to mention it will increase the load on the fridge as you increase the ambient temperature even further inside that mobile greenhouse.

 

Granted, it's not a situation most brits will be familiar with even in mid summer >:-)

 

Essentially, a solar panel has a very similar average yield winter or summer precisely because of the shade seeking nature of summer trips in warmer temperatures. Attached is our solar panel yield chart for the past almost 3 years. The absolute numbers are irelevant so I removed them from the chart, the shape says it all.

 

In our case with the 120W panel we have an average yield of 64Wh per day. This obviously includes days parked at home, on EHU, driving etc. when solar doesn't need to work and you can see it on the chart how the numbers jump up when the van is in use vs. at home. I'm not feeling up to calculating exactly how the average changes if I include only days on off grid trips but typically it's 10-40Wh when parked and the battery is just being maintained and 100-300Wh when out in winter or summer.

 

The maximum power chart does show more seasonal variation but also not as much as one might think. Again, I prefer having a cool van rather than maximum power so look for the shade.

[weldted]

Seeing my system has come up in these posts, a couple of points to note.

 

The inverter is a 1000 watt cont 2000 peak pure sine wave. The only circuits on when driving are the inverter to power the charger and 240 volt to the fridge. The habitation electrics are disabled whilst driving same as they have always been from new by the factory fitted relay working on the D+ signal from the alternator. On my Elddis the mains ehu socket is recessed in a locker next to no1 battery. There is room for the fly lead from the inverter to be kept in this locker even when site electrics ehu is being used. When not on hook up the fly lead is plugged into the ehu socket. This system means the two mains power sources cannot be connected at the same time. This inverter easily powers the 800 watt microwave for around ten mins without bringing the starter battery to below 40% DOD if needed for longer just run the engine. I have fitted a latching relay to disable the battery charger when parked up so the engine battery through the inverter is not trying to charge the leisure battery with the engine off when the engine is running there is a signal from the d+ terminal that cancels the latching relay to allow the leisure batteries to be charged.

I would note that I am a qualified electrician and have extensive knowledge of both ac and dc systems.

All circuits a fuse protected if in doubt please consult one before altering any wiring.

[weldted]

Photos of ehu locker with mains supply connected, inverter supply lead disconnected

Sorry had to send two posts.

 

 

[weldted]

Ehu locker with inverter fly lead connected. With the ehu socket in this recessed locker it enables me to travel with no external leads or additional switch gear required. Also fitted /VICTRON-Blue-Smart-BlueTooth-12V-IP22-BATTERY-CHARGER-15-30A-1 this is fitted with a separate mains socket so either charger can be used in practice the original is off and new one on. But as away for long periods and as not much weight involved original left in place as a back up. By connecting the inverter this way it allows all the 240 volt sockets to be available not forgetting the limitations of the inverter power and battery capacity.

Having had my securimotion regulator fail high up on the way to Andorra we were able to run the Alde heating on 1kw whilst travelling to get a new regulator to protect the boiler -12 c and make a hot drink from the cookers hotplate (not both at the same time) in the several trips away no noticable effect has been noted re fuel consumption.

[spirou]

I took a quick look at our wiring between starter and leisure battery yesterday evening and it might be possible to rip things apart and rewire through existing conduit (hoping wires don't get stuck midway).

 

The two most problematic wires are already 6mm2 as per Schaudt EBL installation diagram yet there's still a ~0.3V drop in those 5-6m of wire. Interestingly however, the WA121525 booster (B2B) manual has those same connections at 10-16mm2. As it's not an expensive device I might choose to go that route to keep things simple. It would also solve my battery combiner issue as it connects on D+ signal, rather than battery voltage since my leisure battery resting voltage is above the disconnect setting thus keeping them connected until I do it manually with a switch.

 

There's a caravan show happening this week and I'm tempted to go there armed with a voltmeter and measure a few things :-D

[aandncaravan]

spirou - 2018-09-10 9:29 AM

 

I took a quick look at our wiring between starter and leisure battery yesterday evening and it might be possible to rip things apart and rewire through existing conduit (hoping wires don't get stuck midway).

 

The two most problematic wires are already 6mm2 as per Schaudt EBL installation diagram yet there's still a ~0.3V drop in those 5-6m of wire. Interestingly however, the WA121525 booster (B2B) manual has those same connections at 10-16mm2. As it's not an expensive device I might choose to go that route to keep things simple. It would also solve my battery combiner issue as it connects on D+ signal, rather than battery voltage since my leisure battery resting voltage is above the disconnect setting thus keeping them connected until I do it manually with a switch.

 

There's a caravan show happening this week and I'm tempted to go there armed with a voltmeter and measure a few things :-D

 

 

 

Spirou, A lot of the batteries taken to the shows are older stock which they sell cheaper to offload them. Get your voltmeter on some of those, you might be surprised how low the volts are on some.

 

 

 

 

 

[aandncaravan]

I should have attached a State Of Charge chart to the above so you can see what the batteries actually are versus what they should be, but only just thought about it, sorry.

 

So below is a chart from Yuasa showing how different technology have different SOC's, Powerframe, AGM and Gel are generally up near 13v but conventional batteries are about 12.6v.

 

The second chart is from AtlasBx/Hankook for their more conventional construction batteries, but the figures pretty much match that of Yuasa Yu.

 

Most of the SOC charts you find are way out of date for modern batteries, and used by Dealers to their advantage!!

 

 

[Billggski]

MMM magazine today looks like it's going to open up another can of worms, with four examples of lithium ferrous installations!

[spirou]

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...

[spirou]

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 >:-) :D 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.

[aandncaravan]

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.

 

 

 

[aandncaravan]

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?

 

 

 

[spirou]

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.

[aandncaravan]

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.

 

 

[Keithl]

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.

[spirou]

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

[Deneb]

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.

[veletron]

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