I intend to install a Blue Smart IP22 Charger into my camper to keep the leisure battery charged whilst on electric hook up.
I already have a pair of cables from the battery to a fuse panel.
My question is that if I was to buy a multiple output model could I connect these battery cables into the charger output 1+, then connect to output 2+ into the fuse panel.
Would this safely charge the battery without affecting the fuse panel?
Would the 12v system work when the charger isn’t on 230v to power a fridge when off grid?
This would save having to run separate cables back to the battery.
Thanks in advance
If you only have one battery (bank) then there is no point in a multiple output charger.
Re the question about the 12V being sufficient to run the fridge, then you need to supply more details about your system and fridge.
Dickie, I think what your asking is “will the IP22 allow current to flow backwards from the battery, through the charger and to your fuse panel?”.
If that is indeed your question, then no. That will not work.
My understanding is that there are 3 MOSFETs that control the current from from each of the 3 outputs dependent upon voltage.
I.e. if you were to charge three batteries, the battery with the lowest voltage would get the lions share of current until the batteries are near equal then they will get an equal charge.
With this in mind, if you do charge multiple batteries they need to be of the same chemistry / charge parameters.
Just a thought but if your cable are sufficient in size and go from your busbar to battery presently, could you not connect your charge output to the busbar?
Hi thank you for your reply.
Yes that’s exactly what I mean. My set up is quite simple but I want to add the charger to keep the battery topped up, I don’t intend on adding more.
If then I connect the charger output to my fuse box, will the charger effectively be supplying 12v power (when on hook up), and also charge the battery?
Then when off hook up the battery supplies 12v to fridge etc when out & about?
Doing it this way will really simplify the job.
Thank you.
I was going to go for the 20A version.
When calculating cable size do you take into account there & back?
Battery to fuse panel is about 3m so do I need an AWG to suit 6m run or just the 3m?
Hi Dickie.
You need to do your calcs on 6m. See the two screen shots from the Victron Toolkit. If you download and open the toolkit and click on the i for info icon in the top right corner it gives you an example of how to do the calcs.
You’ll also find info in the manual for the charger, which you can download from Victron before you buy.
My advice would be to calculate your loads first, i.e. look at the specs for everything, total them all up and then you have your starting point for how much current will flow in the cable. I’d be inclined to over egg it to allow for future additions.
Next considerations is how much current will flow when charging. This will either be 20A or 30A depending on which charger you go for.
I’m not sure what your limiting factors are i.e. unit size or budget etc, but in the same vane as future proofing your load capacity Id be inclined to go with the 30A. If you buy the smart i.e. bluetooth IP22 you can limit the charge current in the software. Check the data sheets ref physical size.
Design your system around the higher of these two numbers i.e. load or charge current. Whichever is the greater.
Next don’t forget to design some fuses into your system between battery and busbar (fuse panel input).
The IP22 has an integral fuse, but it can be awkward to get to thus I upped mine from 40A to 50A and fitted an external 40A which is easier to get to. Your fitting location will dictate.
Lastly, just a though as obviously I don’t know the layout of your van, but would it be possible to locate the charger midpoint between the battery and fuse panel? You could create a busbar mid point where your charger would connect (like a T junction in plumbing) thus halfing your effective charger to battery distance.
REMEMBER - As cables get warm their resistance increases thus causing them to get hotter until the inevitable, thus far better to spend a few more £ and have cables that can adequately carry the maximum current your system can deliver with out generating excessive heat.
Hopefully that is of a little help.
Good luck and happy truckin
Les
Hi thanks again for all that info, very helpful.
I can locate the charger around 1.5 m from the battery which will be about half way to the fuse panel. If I do that then I can easily direct connect to the battery and leave the existing 12v system & fuse panel as is. This keeps it simpler then.
I intend in the future to fully strip out to refit completely.
It would just be nice to have all components together.
If I did connect to the fuse panel would the Victron be supplying the 12v power when on hook up, so reason why 30A would be better?
Effectively Yes. The charger will note the draw on the system and ramp up the amps to maintain its charge cycle whilst also feeding the load.
Hi Les.
If I get the 30A version for future proofing I take it this will be ok for a standard 105ah lead acid leisure battery? No over charging issues?
When I refurb I can then do the calcs to integrate the charger in properly.
The draw on the battery at present is low, just a couple of LED light & water tap pump. I will be adding a 60W (5A) fridge soon to the 12v side, hence the need for the charger.
Thanks again, very informative
No problem at all with using the 30A version. Always look at you battery specs when setting your charge current but you’ll be fine with 30A