Diagrams, Schematics & Wires -- How I Done It --

- Leisure Battery & DC-DC with integrated MPPT & BM2 Monitors -

- Here we have a Redarc 50A DC-DC connected to a leisure battery, (charge Aux Batt when engine running)
- we are also connecting in the Solar PV (charge Aux batt 24/7 when sunny)
- And running loads direct from Aux Battery,
- Using 2x BM2 battery monitors (one on each battery)

View attachment 57429

.

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Aux Battery with seperate DC-DC & MPPT controllers

- Here we have a Redarc 50A DC-DC connected to a AUX battery, (charge Aux Batt when engine running)
- Solar PV on a Victron MPPT (charge Aux batt 24/7 when sunny)
- And running loads direct from Aux Battery,
- Using 2x BM2 battery monitoring APP (one on each battery)
- Using Victron MPPT monitoring APP


View attachment 57440



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Hi
I note you are showing two midi fuses on both positive leads between the batteries and the DC-DC charger.
I have put only one fuse in these leads for my system. Is there an important reason to have the two fuses as shown?
Cheers
 
You should have 2 fuses, each mounted close to their respective batteries.

Each battery is an energy source in the event of a fault.
 
You should have 2 fuses, each mounted close to their respective batteries.

Each battery is an energy source in the event of a fault.
Thanks. I have only fitted a fuse mounted close to each battery. Looking at your schematic I should also have an additional fuse close to the DC-DC charger. I can see your reasoning and Ill make those additions. Cheers
 
You should have 2 fuses, each mounted close to their respective batteries.

Each battery is an energy source in the event of a fault.

Do I still need two fuses on the same length of cable if the DC charger and leisure battery are next to each other, meaning the cable is circa 30cm?
 
Not with such a short length of cable if you can preserve the mechanical integrity of the cable and prevent any shorts to chassis, etc.
 
I've got a caravelle t6 with the factory aux battery, eberspacher air heater and twin leccy sliding doors:

I (mainly thanks to @Dellmassive and his wealth of knowledge via his threads!) understand the factory set up, mine also has been added to with 2 15a feeds going to backboards under the front seats, plus a Victron Ip22 charger and consumer unit with 240v hookup.

1000006344.jpg

Before I start putting together a wiring plan to upgrade and tidy the base electrics to allow for future expansion, I need to know how the factory 3x 15a and 1x 25a fuses (for the 3x 12v sockets and aux heater) are connected to the aux battery. Do they go (as I suspect) via some complicated loom and eventually end up connected to the positive terminal of the aux battery? Or is there some even more complex loom coming from the aux battery going off elsewhere where these fuses are connected?

Basically, am I going to be able to easily shift these 4 feeds onto a separate Busbar? I want to put in a main battery fuse and isolator switch, ideally to a Busbar which all the other positive connections will also go to, which will make things much much easier to manage!

I can't check the battery and connections without removing the passenger seat but I'll do that before putting together a current wiring diagram and a planned diagram for my stage 1.

Eventually I'll upgrade to a B2B charger, solar, LiFePO4 battery. But r first step will be a tidy, extra feed for my kitchen pod that I'll building, and some proper monitoring.

I'm pretty certain the 40a fuses for the sliding doors are on the main starter battery if I'm reading the wiring diagrams correctly.

Cheers
 
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- Leisure Battery & DC-DC with integrated MPPT & BM2 Monitors -

- Here we have a Redarc 50A DC-DC connected to a leisure battery, (charge Aux Batt when engine running)
- we are also connecting in the Solar PV (charge Aux batt 24/7 when sunny)
- And running loads direct from Aux Battery,
- Using 2x BM2 battery monitors (one on each battery)

View attachment 57429

.

*************************************************************************************
Aux Battery with seperate DC-DC & MPPT controllers

- Here we have a Redarc 50A DC-DC connected to a AUX battery, (charge Aux Batt when engine running)
- Solar PV on a Victron MPPT (charge Aux batt 24/7 when sunny)
- And running loads direct from Aux Battery,
- Using 2x BM2 battery monitoring APP (one on each battery)
- Using Victron MPPT monitoring APP


View attachment 57440



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Hi I'm installing 200w solar to a split charge system as in your diagrams

I'm look at either the

Renology DCC50S 12V 50A DC-DC ON-BOARD BATTERY CHARGER WITH MPPT - seems nice n simple

or

Victron MPTT with the Orion-Tr Smart DC-DC Charger Isolated

Question I have is do I need to also install a victron battery protect for either of these?

Initially looking at an 110 AGM battery but may go lithium if I can find a good deal

Many thanks for the infomative posts!

Jim
 
Funnily enough I've just been reading up on battery protects...

They're mainly used to cut off 12v loads before your battery gets to a dangerously low state of charge. They're one-way devices so you can't use a single one for both charging and discharging.

You can use one between your chargers and the battery but that's more used as a remote cut off switch/over voltage protection, which is less common.

So yes it's a good idea to have one to protect your battery from your 12v loads, but you won't need one for your mppt/DC-DC chargers.
 
Renology DCC50S 12V 50A DC-DC ON-BOARD BATTERY CHARGER WITH MPPT - seems nice n simple

or

Victron MPTT with the Orion-Tr Smart DC-DC Charger Isolated
And on this note - rather than the Orion TR you might want to consider the new Orion XS (if you can wait until March) as it's smaller, runs cooler and can change up to 50a.

Comparing the 2, the DCC50s limits the DC-DC to 25a if there's anything coming in on solar, so if you end up going for a big capacity lithium battery you might want to go separate, which will let you get 50a from DC-DC and 25 or 30a from the MPPT.
 
Funnily enough I've just been reading up on battery protects...

They're mainly used to cut off 12v loads before your battery gets to a dangerously low state of charge. They're one-way devices so you can't use a single one for both charging and discharging.

You can use one between your chargers and the battery but that's more used as a remote cut off switch/over voltage protection, which is less common.

So yes it's a good idea to have one to protect your battery from your 12v loads, but you won't need one for your mppt/DC-DC chargers.
Cheers for the response - just couldn't work out wether the Renology had one built in as it seems to have all sorts of protection inbuilt but doesnt specifically say if it stops your battery from running flat
 
And on this note - rather than the Orion TR you might want to consider the new Orion XS (if you can wait until March) as it's smaller, runs cooler and can change up to 50a.

Comparing the 2, the DCC50s limits the DC-DC to 25a if there's anything coming in on solar, so if you end up going for a big capacity lithium battery you might want to go separate, which will let you get 50a from DC-DC and 25 or 30a from the MPPT.
ooh ok great heads up there - i'll check that out as I can probably wait
 
Low battery Protects are(were) mainly used to disconnect the loads from a low voltage SLA/AGM battery.

the were also needed on older DIY Lifepo4s that didnt have a low volt cut off in the BMS. ( ie older green/black Valance lifepo4s)

with modern Lifepo4s - this feature is built into the BMS, so an external unit is not required.
 
Low battery Protects are(were) mainly used to disconnect the loads from a low voltage SLA/AGM battery.

the were also needed on older DIY Lifepo4s that didnt have a low volt cut off in the BMS. ( ie older green/black Valance lifepo4s)

with modern Lifepo4s - this feature is built into the BMS, so an external unit is not required.
Cheers - so use on AGM/SLA but not to worry if I get a new Lifepo4.

the new Orion XS looks good but it also has a good price tag :oops:
 
Aux Battery with seperate DC-DC & MPPT controllers

- Here we have a Redarc 50A DC-DC connected to a AUX battery, (charge Aux Batt when engine running)
- Solar PV on a Victron MPPT (charge Aux batt 24/7 when sunny)
- And running loads direct from Aux Battery,
- Using 2x BM2 battery monitoring APP (one on each battery)
- Using Victron MPPT monitoring APP


upload_2020-1-3_13-46-11.png

Hi @Dellmassive I have based my solar and leisure battery set based on you very informative diagram and advice. So many thanks for this.

Here is what i have:
T6F-PP-DC-DC---mppt-Jimthevan-.jpg

Just a couple of questions before I start the installation if you don't mind please:

Do I need to install a PV isolator? - when would I need to isolate the PV?

BM2 battery monitor - do these give me more info or will they duplicate what info i'll get from the Victron MPPT and Orion units?

Many thanks in advance
 
@jimthevan

Do I need to install a PV isolator? - when would I need to isolate the PV? - its up to you, if you have a lifepo4 battery without low temp protection you may want to switch off the PV over cold winters, or , some dc-dc chargers like the Renogy . . . you need to switch off the PV to get full power from the ALT. or just for diagnostics or testing. ( personally i just use a MC4 connection to disconect if needed)

BM2 battery monitor - do these give me more info or will they duplicate what info i'll get from the Victron MPPT and Orion units? - they offer different data, as in voltage logging over time, a good way to see an overall 12v system health in regards to charge and discharge.
 
@jimthevan

Do I need to install a PV isolator? - when would I need to isolate the PV? - its up to you, if you have a lifepo4 battery without low temp protection you may want to switch off the PV over cold winters, or , some dc-dc chargers like the Renogy . . . you need to switch off the PV to get full power from the ALT. or just for diagnostics or testing. ( personally i just use a MC4 connection to disconect if needed)

BM2 battery monitor - do these give me more info or will they duplicate what info i'll get from the Victron MPPT and Orion units? - they offer different data, as in voltage logging over time, a good way to see an overall 12v system health in regards to charge and discharge.
many thanks for you very speedy response! : )

The Renology Core Lifepo4 has low temp battery protect but I will have MC4 connections so I can just disconnect these if I need to.

BM2s - great I'll fit them to both batteries.

cheers
 
- Leisure Battery & DC-DC with integrated MPPT & BM2 Monitors -

- Here we have a Redarc 50A DC-DC connected to a leisure battery, (charge Aux Batt when engine running)
- we are also connecting in the Solar PV (charge Aux batt 24/7 when sunny)
- And running loads direct from Aux Battery,
- Using 2x BM2 battery monitors (one on each battery)

View attachment 57429

.

*************************************************************************************
Aux Battery with seperate DC-DC & MPPT controllers

- Here we have a Redarc 50A DC-DC connected to a AUX battery, (charge Aux Batt when engine running)
- Solar PV on a Victron MPPT (charge Aux batt 24/7 when sunny)
- And running loads direct from Aux Battery,
- Using 2x BM2 battery monitoring APP (one on each battery)
- Using Victron MPPT monitoring APP


View attachment 57440



...



***************************************************************************************************
Could I change dc dc to

Victron Orion XS 12/12-50A DC-DC Battery Charger or would I be better with the new renogy​

 
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