# CBE technical advice



## RichardD

Does anyone know an expert in the workings on the CBE DS300 electrical distribution unit?

I want to fit a Sterling Power battery to battery charger in preparation for fitting a lithium battery.

Sterling installation instructions are pretty straightforward but they have told me that I need to isolate the existing alternator feed to the DS300 as it will short out the I/P and O/P of the B2B charger when the engine is running.

But if I do that how does the fridge get 12v when on the move and how does the vehicle battery get charged when on EHU.

I've talked to Marcle and Southdown and they both say the same, saying that the fridge is always feed from the leisure battery as the +D feed ensures that it is only feed from there when the engine is running. But they never talk about how the mains charger gets to the vehicle battery. 

Richard


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## Pudsey_Bear

I'm not the best with sparks, but I think the D+ goes direct to a relay, not the control panel, I don't think it needs to, but some vans do have a weird way of doing things, and you have asked those who should know.


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## trek

Hi RichardD

I see your still looking for answers to your conundrum

http://forums.motorhomefacts.com/18...ting-battery-battery-charger.html#post2789313

If you haven't found the answer or the confidence to undertake the modification then just maybe you should knock it on the head and give up on the idea

surely what Carthago fitted at the factory is sufficient for your needs especially as you cant find someone with sufficient knowledge to correctly install this for you


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## RichardD

As I said to you previously I'm after weight saving and 18kg is significant. 

Even without thinking of lithium a B2B offers a much quicker charge-up time which is especially useful when off-grid. A 30min drive can almost fully charge my existing 80Ah gel battery. Solar is not an option due to weight.

As I said I'm not worried about the details or fitting regarding a lithium or B2B's I want to understand the workings of a CBE DS300 which has been fitted in motorhomes for the last 10 years. Surely there must be some technical info on a product that has been around for so many years.

Richard


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## trek

Have you tried asking CBE ?

http://www.cbe.it/en/

Or http://www.aandncaravanservices.co.uk/wiring-your-camper.php ?

As a matter of interest does your Carthago have these CBE "Boite Relais Securite" units fitted .?

As discussed in this link which also contains usful snipets on cbe kit:-

http://forums.outandaboutlive.co.uk...orhome-Matters/CBE-PC200-control-panel/40668/

I think from memory my mates 4 year old Carthago has one under the floor by the table in a floor locker


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## trek

Do you have the system diagram .?


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## trek

http://www.aandncaravanservices.co.uk/battery-to-battery-chargers.php

http://www.aandncaravanservices.co.uk/lithium-batteries.php


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## RichardD

Hi Trek,

Yes, CBE was my first port of call, all they kept saying was to ask my van manufacturer even when I said it was only relating to the DS300. Five times I asked the question in different ways, even marked up the wiring diagram from Marcle (similar to the aandn one you had) website.

I did try Carthago on another issue but never had a response. Their customer service is not that good wanting the dealer to do all that. Will give my dealer another call as the electrical guy was on holiday when I rang them.

I haven't seen this “Boite Relais Securite” on my van so far, but I will certainly look again. 

Thanks for all the links the 'outandaboutlive' made interesting reading but just showed how little is known about this item. There was a link to someone how repairs CBE products but that no longer works.

I also spoke with AandN Caravans, but as their article states they do not fit or repair CBE products, they also couldn't suggest anyone who understands these products.

When this rain stops I will do some more investigation on the wiring, If I disconnect the leisure battery feed to the DS300 this should prove whether the fridge supply come from here when the engine is running. If it does then I could disconnect the alternator feed. This would then just leave the issue of getting the mains charger to charge the vehicle battery whilst on EHU.

I think I'm getting there, thanks for your help so far.

Richard


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## Pudsey_Bear

*they kept saying was to ask my van manufacturer* it seems all of them say this, it doesn't obviate them from helping you, it's just a cop out, but of course they have a point, they sell to the manufacturer who does or more likely doesn't follow their recommendations for fitment, this happens an awful lot with the safety aspect of fridges and heaters etc, they fit things as they see fit, and push safety concerns aside, when I did my self build I looked closely at how they did things in reality as opposed to the installation instructions i had for the same equipment, I was appalled at some of them, they just do as they like and get away with.


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## trek

From the AandN caravan services links I noticed that Schaudt now do a "Booster"

Have a look at the Schaudt WA121545 Booster it maybe possible to use it without a Schaudt power distribution system and it has a lithium setting

http://www.schaudt.gmbh/de/produkte/handelsprodukte_uebersicht/booster.php

Unfortunately its in German but if you contact Schaudt they have a reputation for being helpful

Try [email protected]

Still think your project is more trouble than the 18kg your trying to save

Maybe better ditching your spare wheel and carrier ( i wouldnt want to ) or driving without any water in your tanks

Remind us are you replating your camper from above 3500 to below?


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## trek

That DS300 diagram doesnt show a connection from the mains charger to Battery 1 (pressumably engine battery) only to battery 2 ( leisure ) so you need to establish if both batteries get a charge when on a hook up


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## Pudsey_Bear

Translation for Treks link

Booster 12V DC
Application with living room battery in the motorhome or in the caravan
*** NEW! ***
WA 121545 for motorhomes
The WA 121545 booster is designed for optimum charging of lead acid / lead gel, AGM1 and AGM2 batteries as well as lithium batteries while driving in 12 V electrical systems. The connected living area battery is charged independently of the alternator voltage. Switching to load maintenance is current- or time-dependent and automatic.

When a battery temperature sensor is connected, the charging voltages are adjusted to the battery temperature. 
For optimal charging, without overloading the starter battery circuit, not only the voltage of the living space battery, but also the voltage of the starter battery is measured by a voltage sensor.
In EURO6 vehicles, modern alternators with energy-saving charging strategies are installed. Here, the use of a booster is necessary. In these alternators, the charging voltage varies greatly depending on the driving condition (eg MB Sprinter 12.6V - 15.0V). When accelerating or when sufficient starter battery charge the alternator voltage is greatly reduced, but greatly increased during braking to save energy through recuperation. 
This prevents - without booster - an optimal charge of the living area battery, or even leads in a fully charged via the 230V power battery to its discharge.
In conventional alternators, the living space battery charge is also improved by using the WA 121545 booster. Especially with long charging lines, the charging current is significantly higher. For AGM batteries that require a charging voltage of 14.7V, the use of a booster is indispensable. 

The WA 121545 booster is a clocked step-up / step-down converter that compensates for fluctuating alternator voltage and provides a high charging current. When the alternator signal "D +" is present, it goes into operation. He has a very high efficiency. This allows a very compact and lightweight construction. The built-in fan is very quiet and runs only at high power
Charging characteristic: IUoU (current-dependent switching to charge retention)
adjustable battery types:
Lead Acid Battery: 14.4V / 13.4V
Lead gel battery: 14.4V / 13.8V
AGM1 battery: 14.4V / 13.8V
AGM2 battery: 14.7V / 13.7V
Lithium battery: 14.4V constant (CCCV or IU characteristic for LiFePO4 batteries with their own battery management system)
Temperature compensation: automatically after connection of the temperature sensor
Input voltage range: 12.0V - 15.0V
Maximum charging current adjustable in four steps: 45A / 55A / 63A / 70A
Efficiency: ≥ 93% at maximum charging current
Comment on the booster test 'Motorhome International' in the August issue 2017
WA 121525 for motorhomes
The WA121525 booster optimally charges WA 1215256-cell 12V lead-acid, lead-gel AGM and lithium batteries in motorhomes while traveling, regardless of the alternator voltage. 
Installation is theoretically possible in all motorhomes. In cases where the charger and refrigerator leads are not separately wired from the starter battery, additional components are required for installation. Please contact your dealer.
In vehicles with alternators with energy-saving charging strategies (Euro 6), the use of a booster is absolutely necessary because the charging voltage of the alternator can vary greatly (12.6 - 15.0V).

In conventional alternators, the living space 
battery charge is also improved by using the WA121525 booster. For AGM batteries that require a charging voltage of 14.7V or more, the use of a booster is indispensable.

The WA121525 booster is a clocked step-up / step-down converter that 
compensates for fluctuating alternator voltage and provides a high charging current. 
Optionally, a temperature sensor can be connected.

Charging characteristics for lead acid, lead gel, AGM and lithium batteries
Temperature compensated charge with optional temperature sensor
Charging current typ. 25A, short-term 30A
Charging voltage up to 14.7V (with temperature sensor up to 15.1V) depending on the set battery type
Charging characteristic IU0U
Comment on the booster test 'Motorhome International' in the August issue 2017
WA 1208 for caravans
The WA 1208 booster increases the charging voltage WA 1208available in the caravan to a maximum of 14.4V, so that the caravan battery is optimally charged when driving. 
The booster disconnects the caravan battery from the towing vehicle when the engine and ignition are off.


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## RichardD

No, due to medical I'm restricted to 3500kgs.

I ordered the van without a spare wheel and tyre and I run with only 20 litres of water as all new vans of 3500kgs now have this intermediate drain tap so manufacturers can claim that they've got the lightest van on the market.

When they quote their unladened weight it only includes 20 litres of water. Also their ex-factory weights are extremely optimistic. Yes I know they always state +/- 5% but on a 3000 kg van that could be up to 150kgs off your payload. I've have taken it to a weighbridge and I think they are about 55kgs over the declared ex-factory weight. When I enquire of the dealer before I bought the van about weights they all said they are pretty accurate. One dealer even said they are usually under!!!

The Schaudt booster, when I've translated it appears to be the equivalent of the Sterling B2B. It does make a comment about mains charging and fridges to consult your dealer.

Anyway I'm always up for a challenge. I'll keep digging away until I get an answer.

Richard


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## WildThingsKev

Having actually done this with a CBE system I can only reiterate what I said on the other tread, which is that my habitation batteries are totally disconnected from the habitation side during b2b charging and everything (fridge included) works perfectly.


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## RichardD

Hi Kev,

I was asking again because the two supposed authorities and Sterling said to isolate the alternator feed to the CBE DS300. I think you've isolated the leisure battery by a changeover relay.

Marcle and Southdown said that the fridge is fed via the leisure battery supported by the alternator when the engine is running. But if it was then your fridge wouldn't work as your changeover relay isolates the hab battery. 

Richard


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## Pudsey_Bear

No, deffo the fridge is fed via the alternator, which feeds the VB on any van I've seen, and the LB to charge only, on a self build though it is more simple, you don't touch the alternator at all, you fit a voltage sensing relay to the VB, with a light trigger wire, when the relay senses a charge, it connects the big terminals on the relay between the VB positive and the fridge, it also feeds to the LB to charge them up.


The only time I would think the fridge is fed by the LB would be a for a compressor fridge, not a 3 way.


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## RichardD

The Schaudt booster could well be the answer as the wiring diagram on the A and N caravans site shows it wired in the alternator to EBL or in my case the CBE DS300.

Will find out more when A and N are open on Tuesday. Surprising they didn't suggest this item when we had an email discussion about a month ago.

Richard


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## trek

> The Schaudt booster could well be the answer as the wiring diagram on the A and N caravans site shows it wired in the alternator to EBL or in my case the CBE DS300.


Yes i though the same looking at the different wiring options in the instructions


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## RichardD

Thanks trek, I'll let you know what A and N have to say about using it with a CBE DS300.

Richard


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## Chasn2017

I have recently finished installing lithium batteries (2x Victron 90Ahr), battery management unit (BMS200) and battery-battery charger (Sterling BB1260). I have also fitted solar panels ( 2x 130W semi flexible with ETFE coating) on homemade frames which reduce the rigid installed weight to 5kg /panel. There will be an article about the panel choice and frame design in MMM soon. I also used a Votronic 350W MPPT regulator which also looks after the vehicle battery after the habitation battery has been topped up. With regards to the wiring, Victron control the charging and discharging of their lithium batteries on the negative side of the batteries through the BMS200. To achieve this the CBE negative needs to be disconnected from the standard chassis ground and connected to the LB terminal of the BMS200. As the CBE positive also needs disconnecting, in my motorhome (a Carthago Tourer I 143) it was possible to use part of the now unused positive cable as the new negative cable. This only requires a new cable across the width of the vehicle making the new negative cable installation much easier. There was some concern about power getting to the fridge with the vehicle battery disconnected from the CBE. In practice this is not an issue. I suspect that the output to the fridge is just switched on from the habitation battery within the CBE whenever it senses the battery voltage is raised by charging. I have attached my wiring diagram in case it is of any help to others.


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## RichardD

Hi, thanks for that info, I'll study the diagram as I'm not having solar or an inverter. Can you advise which are the connections to and from the CBE300.

Richard


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## Chasn2017

I am not near my motorhome at the moment to check, but assuming that I have the same CBE300 this is what I did to modify the system to accommodate the Victron lithium batteries:
1. Isolate both batteries from the system.
2. The CBE has three main heavy duty cables connected using 10mm nuts. Two are red (one positive for each battery) and one is black (negative chassis connection).
3. Disconnect the heavy duty black lead and cover its terminal with heatshrink or tape.
4. Disconnect the vehicle battery positive, apply black heatshrink to several inches of the cable to avoid confusion and connect it to the negative terminal on the CBE.
5. Route a new heavy duty black cable from the LB connection on the BMS200 across the width of the motorhome on the lower floor to the locker forward of the habitation door. White rectangular ducting with self adhesive backing was used to contain the cable.
6. Inside that locker is a white metal trim strip on the floor which covers the mass of wiring routing fore and aft. One of these is the heavy duty red cable which connects the CBE to the vehicle battery. Cut this, insulate the forward end, apply black heatshrink to the aft end and connect it to the new black cable. 
7. The Sterling BB1260 was attached to the forward bulkhead of the habitation battery compartment. The new positive cable from it to the vehicle battery was routed through a hole drilled in the bulkhead and under the passenger seat. Within the vehicle battery compartment there is enough space to connect up an extra 70A fuse to protect the cable between the battery and the BB1260.
8. Reconnect both batteries.

Hope this helps.


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## RichardD

Thanks for that it helps a lot.

On your diagram does the EBC supposed to read CBE?

My C-Tourer-i144QB doesn't have a locker forward of the habitation but the battery locker is under the lounge seating area. Wonder where my large cables go through to the vehicle battery. I would have hoped that they would be in the battery locker somewhere. Need to do some investigation over the winter period.

I'm hoping to use a lithium battery which has built-in BMS like the ReLion brand so I'm assuming that you would link together the blue and green heavy cables in your diagram on the Victron BMS200 item?


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## Chasn2017

Yes the EBC is another abbreviation for the CBE.

Is your CBE in the garage? If so it is still likely that the wiring routes forward on the right side of the vehicle. 

If you are using a different lithium battery system you need to wire it according to their recommendations. Whatever BMS system you have it is important that, if it senses a problem with voltage or temperature, it can isolate the lithium battery from the rest of the system. It may be that other systems may do this on the positive side of the battery so the wiring would then be different. Also I am unsure whether other systems need the habitation earth to be separate from the vehicle earth. If you can establish what the manufacturer of your lithium battery system requires for wiring I might be able to help you adapt it for your vehicle. I live in Wiltshire and could meet up to help you research the wiring layout for your vehicle. It is very frustrating that Carthago do not provide wiring diagrams for their vehicles.
Rgds
Nigel


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