rohan avatar image

New caravan ac, dc-dc and solar charging


I need some help to determine exactly what I need equipment wise for a caravan

My requirement is as follows:

To ensure AC Charging

Dc to dc charging while driving

Solar charging while not connected to AC

This is what I would like to use:

2 x 150 watt solar panel

2x Rolls 140ah lead batteries

1x Victron ip22 blue smart charger 30ah 3 inputs

1x Victron Orion 24v-12v 70ah non isolated ip20 dc to dc charger

1x Victron smartsolar 100v/20ah solar controller

1x Victron bmv 712 battery management

My questions as follows:

1. Will all products from Victron work for this setup?

2. Do I have the correct dc to dc charger to ensure batteries charge while travelling?

3. Is the dc to dc charger euro 6 compatible?

4. What else do I need like battery protectors or anything else?

5. Could Victron help with a wiring diagram for this setup?

I am ok with how the solar and ac charger works and chargers the batteries but uncertain exactly how the dc to dc is connected in this setup..

Really grateful if everyone could comment or assist.


victron products
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3 Answers
Justin Cook - Bay Marine Supply USA avatar image
Justin Cook - Bay Marine Supply USA answered ·

Hi @Rohan,

I was waiting for anyone else to answer, but I think what you'll find is that system design, schematic production, and component review is a time-intensive process that isn't cheap; your local Victron distributor will very possibly offer such services -for a fee, of course- and there are any number of private consultants who have varying rates. My best advice is to hire a consultant to produce a schematic for you, calculate your cable runs and gauges and fusing needs and etc., and a professional installer to put it all together. This is not something anyone reputable would ever recommend that you do yourself if you're not experienced, as a single loose or mistaken connection can destroy an entire system - or worse.

Victron has published a number of generic wiring schematic examples, but they produce professional-grade equipment that is intended to be sold to and installed by professionals, so to my knowledge they do not offer custom schematic services... the presumption being that a professional installer already knows the products and will make his or her own schematics.

Several distributors that I know of -including the one I work for- will charge you for design and consultation work and will then give you a credit for some of that amount toward your actual purchase, so that can be helpful if you're on a budget. Bottom line, though, is that anyone who will do this work for free is not who you want doing it. If you already have schematics drawn up, there are plenty of people who will be willing to glance at them and offer quick advice, and honestly there are calculators all over the internet that will help you with wire run and cable gauge calculations, fuse sizing, and etc... here's a great resource, for instance: , and there are many more like that if you are willing to put in the work yourself.

Be prepared, if you're trying to sort this all out yourself, to spend countless hours researching and calculating, and days correctly installing components. That's why, if you have the budget, it will really be worth your while to just hire a professional installer or other consultant to lay everything out for you.

As a note, more directly addressing your questions, the Orion isn't an ideal batt-to-batt charging solution because it's a flatline charger. You turn it on, it puts out X amps at Y voltage, you turn it off. It doesn't have the 3- to 4-stage intelligent charging profile that you want for B2B charging. It'll technically work, it's just... if you're putting a lot of money and time and effort into your van conversion, this is not the solution you want. There are two main ways around this: You can either be patient and wait until early next year for Victron to release their B2B charger, or buy a Sterling B2B (which is Euro 6 compatible) now. I work for a Victron/Sterling/Blue Sea/Bussman distributor and can personally speak for the robustness and dependability of the Sterling units... Sure, they're not blue, and they're not Bluetooth-enabled, but once they're installed and programmed correctly, they're pretty much bulletproof as far as dependability goes.

Otherwise, other than the missing fuses/breakers/distribution panels, etc, yes all of this equipment will work well together. If you go with a Sterling, it will also play well with everything... Sterling components don't talk to Victron components, of course, but they don't need to... the BMV will register the charging, and that's all you really need.

Good luck!

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rohan avatar image
rohan answered ·

Hi Justin,

Thank you for the reply, all makes sense and a very comprehensive response.

I think it's made out more complex than what it is. I have installed solar on my current trailer. It works perfectly and took a day to install. I am willing to wait till next year to see the new dc to dc chargers. Although the buck boost 50ah seems to be another option??

Ctek 250 with smart pass 120 and M25 charger also appear to be very viable options and they are very easy to install. They just don't have Bluetooth but do have a battery management monitor

I would be interested to hear your thoughts on the ctek system and if you believe there are any down sides to it?



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pstrong avatar image
pstrong answered ·

Hi Rohan,

Did you end up doing a diagram of any sorts? Im looking to do pretty much similar components in my new caravan.

You happy with these components?



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