[Guide] DC-DC Charger (for leisure battery) -- How I Done It --

@Soundz


The 12/12/30 is advertised as 30A, at 40degC temp continuous.

It's actually capable of 40A for sort durations and has an absolute max of 60A
.

That's why you need a 60A fuse.

And in any case fitting a 30A fuse on a 30A circuit is a recipie for disaster....the fuse will get hot and melt the holder.... At 30A fuse might not actually blow untill 40 or 50A. (Depending on the ambient temp, thermal mass of the fuse and holder, voltage , current which will all add up to either a quick blow or slow blow of the fuse...... Or just get hot and melt)

A fuse it fitted to protect the cable, not the device.

The fuse must be the correct size for the cable.

The cable must be the correct size for the load.... The 12/12/30 in this case.

So I would follow the manufacturer guidelines and fit a cable run suitable of carrying the max 60A+overrate @25% and fuse at the recommended 60A.

thats a 16mm2 cable and a 60A MIDI style fuse. ( well two fuses, one at the starter battery, and one at the leisure battery - see below)

Knowing that the 12/12/30 will pull 30-40A max.... Which will keep your cable run and 60A fuse cool..

There is also the volt drop to consider... Fatter cable, fatter fuse means less volt drop leaving more power for your charger to play with.




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Fwiw ...

I have a 12/12/30 .... It's very good as is all the Victron stuff ...

BUT.

It's very big in size.!

It get very hot when running! (At 30A)


Compared to the 50A Renogy which I'm running now that stays cool as a cucumber..

I don't know why the unit is so big or why it gets so hot for a 30A box.

But take those into consideration and it's a good unit.


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So be cautious of what your being told.... And defo don't fit a 30A fuse. !!!

Always follow the manufacturer guidance.



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Damn what a fantastic reply bless ya Dell. Lecctrickery is basically physics tis laws of nature stuff, so in my simple little world varaibles like this fuse worry me as logic should prevail.so yes huge caution huge huge caution . Del I am a laymen... sure I've tried/ am trying to show due diligence.. but it's difficult for me to debate with fitters/sparrkies as I don't have that info to hand it's buried away in my head or places that I refer back too. IE the above victron manual put it another way I'm not the sharpest tool in the box:D

Great stuff bud points well made an in an easy to understand logical way.............. will follow the victron manuals 60A fuses here ready to go;)

I'm aware of the size of orion ( it's here......... haha very aware of heat aspect of the Orion.... very aware!! the reason I was linked to your threads was researching that very point......


many thanks
 
Hi Dell, I believe the Victron has passive heatsinks ; i.e. no fans, so no noise. Is the Renology the same?

@Dilbert

Yes . . The Renogy DC50/30S black DC-DC + MPPT units are fanless. (and run cool)










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BUT . . .

The Blue sided DC-DC ( without MPPT solar) - DO HAVE FANS.









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i have the 20A blue side model. . . . - [Guide] DC-DC Charger (for leisure battery) -- How I Done It --


its ok, but i wouldn't recommend it. . . its an ok basic dc-dc.

it gets hot and runs the fans even at just 20A . . . they do a 40A and 60A version also.


i much prefer the DC50s with mppt version - [Guide] DC-DC Charger (for leisure battery) -- How I Done It --




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Shame the Victron gets so hot. It looks like they have a less efficient switch mode regulator giving more loss.

I like the Victron kit and everything else in my setup is Victron and I prefer a single app and VE network solution.

Still using the the Sterling BB1230 at the moment but that does have fans.
 
Shame the Victron gets so hot. It looks like they have a less efficient switch mode regulator giving more loss.

I like the Victron kit and everything else in my setup is Victron and I prefer a single app and VE network solution.

Still using the the Sterling BB1230 at the moment but that does have fans.
Agreed . . im the same, all victron now.

But . . . The Orion DC_DC got swapped back out fairly quickly.

++

The Renogy DC50s is a very good DC-DC that is also programmable vis the APP ( with the BT-2 BT adapter),

you can set the charge profile, battery chemistry type, tweek the charge voltage . . . . even set a current limiter - Ie change from 50A to 20A if you wish.

you cant do that with many DC-DC chargers.

it just make my life easier when constantly swapping different kit in/out of the van for testing.

+++++++++++

im going to swap the Renogy out for the REDARC BCDC1250D 50A this week for a good test with the ROAMER 230SB battery.

i want to see how hot it gets when running at 50A . . . . but the only adjustment with the REDARC is the chemistry type . .

the profile and charge voltage is pre-set.


+++++++++++
 
Hi great thread, I bought the Victron Orion tr smart 12/12 30a and I am wondering how to connect up the engine on wire. Would it be okay to connect a wire to the display fuse from the victron as this only comes on when the van is running or is there a preferred fuse to piggy back off.?
I am currently running in auto mode but have noticed the charging only comes on when the alternator is charging the main battery so flicks on for a moment or two which doesn’t seem very efficient.

Many thanks
Daniel
 
@djgriff the centre line of fuses on the SC fuse box (T6) is IGN switched.

Or go direct to the BCM for OEM engine run signal.

There is also a pdf on the Victron website that explains the auto feature and how to tweek the settings.
 
BCM is the body control module....

It's the ECU that controls most of the vans electric s...

Have a look back to the start of this thread... Post 1 for more info.

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The OEM setup uses a engine running signal to turn on the relay for the two battery s.... You can retrofit the same feature and use it to trigger your DC-DC charger.
 
BCM is the body control module....

It's the ECU that controls most of the vans electric s...

Have a look back to the start of this thread... Post 1 for more info.

.



.


The OEM setup uses a engine running signal to turn on the relay for the two battery s.... You can retrofit the same feature and use it to trigger your DC-DC charger.
Thanks
 
I have cetec DC-DC system (AGM battery, wire to ignition on and to earth connected).
When ignition off I connect battery charger to main battery the ctec leisure battery charger also starts chargeing.

Is this a ctec feature and i can leave the battery charger connected to the main battery and every time i turn the charger on it charges the leisure battery also?
 
I have cetec DC-DC system (AGM battery, wire to ignition on and to earth connected).
When ignition off I connect battery charger to main battery the ctec leisure battery charger also starts chargeing.

Is this a ctec feature and i can leave the battery charger connected to the main battery and every time i turn the charger on it charges the leisure battery also?
yes its a feature . . .

i call it AUTO VSR feature . . .

more info:





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This is my DC-DC set-up.
After running for a month i starting to get "Battery not charging" warning. It game and went away until the dealer replaced the voltage regulator.
At the moment i keep running with the DC-DC set up disconnected for a few month.
Has anybody else got this on T.6.1 TDI?




View attachment 135573View attachment 135580

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Since october it was fine, in february it poped the message.


I connected the dc-dc system back in april, it has been fine since now.


It started to again.

I have dc-dc system disconnected (no fuse in the AGU holder), also the engine live input wire.

I monitored the Cteck battery sense.
This is what is going on:
Messege appears (battery not chargeing…)
Battery sense reads above 12V
After 15 min of driveing the messege goes away.
Battery sense reads startes to grow until 14,…V
It stopes the chargeing, voltage goes down to 12V

No messege.

Until the car startes the next chargeing cycle and it popes the message again.

I drive motorway 2 houres, started 91% ended 93% battery charged.


Also i have second issue, it also was present in october, when the chargeing issue appeared.

I have the right slideing door with soft-close.
When i close the door, i can hear the locking mechanism closeing the door.
When I drive away it popes the message electric child lock error.
 
had the seat out again . . . so time to play with a different setup . .


i swapped out the Renogy DCC50s out for the Redarc bcdc1250d

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and very compact small unit , , , ,

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charging like a champ.

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I have cteck d250se, 110ah leisure battery with no solar.
Consumers are playstation 10A, two fridges combained 8A.

Atfer i have my battery drained to 15…20% and start the journey, the battery level goes even down so I have to turn off one fridge.

Is it that the 20amp d250se can not provide needed charge?

I would like to have a full battery again after 2h of driveing.

What is the solution, to use more powerful dc-dc charger or ad Smartpass120?
 
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I have cteck d250se, 110ah leisure battery with no solar.
Consumers are playstation 10A, two fridges combained 8A.

Atfer i have my battery drained to 15…20% and start the journey, the battery level goes even down so I have to turn off one fridge.

Is it that the 20amp d250se can not provide needed charge?

I would like to have a full battery again after 2h of driveing.

What is the solution, to use more powerful dc-dc charger or ad Smartpass120?
D250Se is around 20A charge in bulk . . .

what battery are you using? - could the battery be getting on and not taking a good charge?

what are you using to meter out the 15-20% - ? a shunt?

post a few pics and well have a look.
 
had the seat out again . . . so time to play with a different setup . .


i swapped out the Renogy DCC50s out for the Redarc bcdc1250d

View attachment 161626


and very compact small unit , , , ,

View attachment 161627

...


charging like a champ.

View attachment 161628View attachment 161629View attachment 161630View attachment 161631
What's the Redarc one like compared to the Renogy?
Do you know how they manage to make is so small and with no heat sink, does it not get very hot working at 50A?
 
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I am useing cteck BM.

I am useing exide, it is 1 year old.

Can the problem be also, that d250se has it own charging cycles and beacuse i use 18A it cant get past the first cycle?

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What's the Redarc one like compared to the Renogy?
Do you know how they manage to make is so small and with no heat sink, does it not get very hot working at 50A?
the redarc is much smaller. . . the whole unit is made from extruded ALU, so the whole thing is the heatsink.

yes it get hot at 50A, - but doesn't get hot at 30A,

its more expensive than the Renogy,

it doesnt have any monitoring APP like the Renogy.

its not programmable like the Renogy.

it is duel like the Renogy ( takes solar - but id leave the solar on separate mppt )

....................


i love both units. . .

if you need a small unit - get the redarc

if you want programming and the monitoring APP get the renogy.


either option works very well.

++++++++

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