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Considering an Orion TR smart on the battery isolator output for a Li bank

I was considering using an Orion TR-smart between my battery isolator and my 4x100Ah LiFePO4 bank. The isolator has 5 connections 2 alternator inputs and 3 battery outputs. The application is on a a catamaran where my solar PV panels charge my Li batteries very well most of the time, The isolator is connected to the Hitachi 80A alternators on my port and starboard engines, and the outputs are connected to two 100Ah AGM starter batteries (outputs 1 and 2) and the 400Ah LiFePO4 house bank (output 3). I was concerned that if I were to run an engine or two, and my Li bank was not nearly charged I could end up overheating my alternator(s) by drawing too much current. With the batteries nearly fully charged I still saw the Li bank draw 50A from an alternator when one engine was running. Would the 30A Orion TR smart not only provide a current limit of 30A being drawn for the output #3, while also providing the optimal charging voltage for the Li bank at the same time the AGMs were charging at the appropriate voltage?

lacadienne asked
gussie edited ·

3 Answers

DC to DC converter to load output of bluesolar 75/15

I have a small solar powered system installed to run my domestic central heating pumps and controls in the winter. It has evolved over the years from a 12 v Pb with PWM system to a diy 24v Li-ion with bluesolar MPPT 75/15.

A couple of years ago when i changed to 24v Li-ion i had to install a DC to DC converter to run my control gear and pumps. The bluesolar MPPT 75/15 would not accept the converter connected to the load output, simply no out put, I guess it saw it as a short circuit. So i connected straight to the battery.

Present day I am evolving the system further and have th 75/15 conected to a Raspberry pi with venus Large os. but obviously i cannot see what loads i am running as they are direct to the battery.

The DCtoDC converter is not a victron, would a victron converter be any different?

Can i install a resister across the load output to over come bluesolar MPPT 75/15 seeing a fault?

any advice would be great,

rickpickle asked
rickpickle answered ·

4 Answers

DC DC Converter 24/48 2.5A output 4.5A . help

I connected the orion 24/48 120w 2.5A converter to an inverter. But when measuring the current I have 4.5A at the output of the converter. The converter is specified as 2.5A. I set it to 48V, 120W. Battery 24V 120AH. What could be the reason, defekt or is it normal?

martinp2008 asked
martinp2008 answered ·

2 Answers

DC DC Converter 24/48 2.5A output 4.5A

I connected the orion 24/48 120w 2.5A converter to an inverter. But when measuring the current I have 4.5A at the output of the converter. The converter is specified as 2.5A. I set it to 48V, 120W. Battery 24V 120AH. What could be the reason or is it normal?

martinp2008 asked

0 Answers

Orion 24/48 2.5A DC DC wandler gibt 4.5A statt 2.5A raus

Ich habe den orion 24/48 120w 2.5A wandler an einem wechselrichter angeschlossen. Doch bei Messung des Strom habe ich am Ausgang vom wandler 4.5A . Angegeben ist der wandler aber mit 2.5A. Eingestellt hab ich ihn auf 48V, 120W. Batterie 24V 120AH. Woran kann das liegen oder ist das normal ?

martinp2008 asked

0 Answers

Does the Buck-Boost DC-DC Converter meet ECE Reg 10?


Can someone tell me if the

Buck-Boost DC-DC Converter meets ECE Reg 10 certification?


nic-sama asked

0 Answers

Campervan Schematics


Hi All,

I have finished my first revision of the campervan schematics, I am sure I would have forgotten a few items (such as the Dometic fridge, a shower solution etc), but this is the general installation. I wanted some people to check it over and to see if everything looks legit in terms of wiring etc. I suspect the solar wattage should be enough considering I have the DC-DC charger? Also in terms of AC power, can someone advise on a suitable distribution box that will work seamlessly with the Multiplus and the correct wire sizes for this also please?

Let me know if anything looks wrong. I plan to fit what I can and get it approved by an electrician.

campervandan asked
campervandan commented ·

3 Answers

charger 2 batteries

hi i have to replace the diode on my boat from the 80;s which would be best orion dc dc charger or dc dc converter can some explain the difference thx colin

colin305 asked
colin305 commented ·

1 Answer

Orion DC DC Converter operating temperature

Hello, It's mentioned in Orion Datasheet that Operating temperature range is -20 to +55°C, What will be the risk if the ambient temperature exceeds 55°C? Will we have only an output derate? is there the possibility of shutdown

nour asked

0 Answers

Orion-Tr 12/24-20 installation

Hi again

In a previous post I shared the scheme of my Van electrical system. It is almost set now, but I have some small doubts...


Mostly about Negative / Ground

here I share a scheme with three options on how to connect Orion 12/24 to the negative busbar
which one is more correct?


many thanks

pepvan asked
Matthias Lange - DE answered ·

1 Answer

Is it ok to share input and output ground on Isolated Orion TR Smart?

Hi, I have an Isolated Orion Tr Smart on my van and currently running a long positive 6awg wire from rear of the van to the alternator battery. Is it ok to ground both input and output to my chassis ground on the back of the van to prevent running a long negative wire to the front?

manny-martinez asked
Matthias Lange - DE answered ·

1 Answer

Cigarette lighter to supply dc to dc charger?

Does there exist a Victron dc to dc charger capable of drawing solely off a car cigarette lighter without more complex wiring? Perhaps the Orion 12/9? The use case would be to charge a 100ah LiFePo4 battery in my ultra-portable diy solar generator during the long drives between camp sites. Jackery products can charge this way, so I'm trying to figure out how add similar capacity to my diy build, understanding of course that charge times would be slow.

jake2664 asked
nbezanson answered ·

2 Answers

Orion-Tr Smart 12/12-18 'Charge is Disabled' but still charging at low amp

I have an Orion-Tr Smart 12/12-18 Isolated charger installed in my travel trailer, but it only charges my battery @ 5-6 amps, and the app actually shows 'charge is disabled', would appreciate it if someone could help figure out what's wrong, some additional information:

- Charger is connected through my SUV's 7pin cable, the 12v charging wire in 7pin cable has a 20A fuse in SUV's fusebox.

- Although it's isolated charger, I had to connect both input ground and output ground wire to my trailer's ground busbar, as I need a common ground for other wires (brake, turn signals) in the 7pin cable.

- I also wired the running light wire of 7pin to charger's switch pin, and verified when I turn off the running light from SUV, not charging was happening and when I turn it on, charge resumes at 5amp.

- I was charging 200ah 40% SOC LiFePo4 batteries, which should be able to take way more amps than 5amp.

- SUV's alternator is rated 180A.

- The app actually displayed 'charge is disabled'

Anything wrong? I also noticed when I changes the settings from config, it actually trip the fuse twice, indicates somehow there was > 20a current flow through fuse/wire,


hovr asked

0 Answers

Can I connect two Isolated Orion converters powered from different battery banks?

I want to have a common DC bus for powering a system. We already have a battery bank that has been working for a couple years and we are adding a new battery bank for expansion. Can I include an Isolated Orion DC-DC at each battery bank prior to the Bus to couple all the loads in one bus?

macevedo asked

0 Answers

Orion 12/12 30A with existing split charge

I'm about to install an Orion 12/12 30A charger to optimise the charge to the leisure battery from the alternator in my motorhome while driving.

The motorhome is a 2010 Autotrail Apache, with a Sargent EC225 control unit and EM50 interface unit.

The reason for the change is that I am also installing LiFePO4 batteries. I already have a Victron MPPT solar controller and a Victron mains charger, so those charging methods are OK for lithium, and I want to make sure that the alternator charging is also optimised for Lithium and doesn't cause any problems, hence the installation of the Orion.

My problem though is that it seems there is no way to disconnect the existing charge to the leisure batteries from the alternator, without also disconnecting other critical connections. I spoke to Sargent who confirmed this to me. They say that the only way to disconnect their split charge relay to stop the alternator charging the leisure battery would also stop the 3-way fridge running on 12v when the engine is running, stop the step retracting, and cut off the EMC relay.

So my 2 questions are:

1) Does anybody have any knowledge or experience in disconnecting the existing alternator-leisure battery charge in this setup, without any detriment elsewhere?

2) If I install the Orion but left the existing setup in place, would that cause a problem or prevent the Orion from working properly?

Many thanks

burtonwisher asked

0 Answers

How to setup multiple chargers connecting simultaneously.


I have purchased the following devices and I am starting to setup the system on my Boat, where I have a Starter Battery and a House Battery:

  • Blue Power Charger 12 30 3
  • Smart solar MPPT 100 30
  • Orion-TR Smart 12 12 - 30
  • Smart Battery Protect 12/24 100
  • BMV-712 Smart
  • 2 x Victron 12V 175W Mono Solar Panels

My question relates to situation in which these devices will all be working at the same time.

The AC/DC and DC/DC Charger, will rarely do that, as I will either be on Shore Power or on Engine Power, but there could be very rare instances of the engines being run while on the dock for a few minutes when also still connected on Shore power.

My main concern is the MPPT Solar Charger running at the same time as the DC/DC Charger when under way and in daylight. But technically, if I am in the situation described above at the dock, all three chargers could be working at the same time, for some short period of time.

Can this damage the devices or the Battery? At present the Battery is a AGM 100Ah Deep Cycle but I will soon be replacing it with a LiFePO4.

Can someone please recommend the best way to setup this system? Am I better off switching manually things on off based on the usage? Or can I setup the devices parameters in such a way that they will automatically stop working at the right time based on the voltage produced by other devices?

I would appreciate some guidance and help.

Thank you in advance,


adric asked
2gottmo edited ·

2 Answers

Wire Size for DC-DC 30/30/12 converter?

Hi all! Excited to have found this forum. I have designed my system so that my electrical system is on the opposite side of my van from the starter battery. I have realized that the recommended wire size will not sufficiently carry the current - is there a way to use a bigger wire? Is that set up a really bad idea? I estimate the total distance to be maybe 40 ft (both ways).

mbohrson asked

0 Answers

Using both a DC/DC and a MPPT Charger


I am planning on using the Victron Orion TR-Smart 12 12 30 Isolated to charge a LiFeP04 House Battery from the Start Battery of an outboard Alternator.

However, I am also planning on adding solar, to top up the house battery when we are not running the outboard. For this purpose, I am considering the Victron SmartSolar MPPT 100/30, but I am now wondering how the charging would switch between the two systems? Does Victron have a Smart integrated MPPT/DC2DC Charger? Or can it be achieved differently with Victron devices? I know of other branded products that do this.

Can I connect simultaneously both Victron units to the House battery?



adric asked
daineric commented ·

3 Answers

Two batteries MPPT connected to 12-24 DC DC Charger

Hi, I have a single solar panel connected to a two batteries MPPT solar charger.

Battery 1 is 12V and is directly connected to the port 1 of the solar charger.

Battery 2 is 24V and I would like to know if I can connect port 2 of the solar charger to the input of the Victron isolated DC DC 12|24 Charger so I can solar charge the 24V battery as well.

Each negative has its own connection.


mporta71 asked
mporta71 answered ·

1 Answer

Orion Tr Smart 12/12 18A isolated and 7-way trailer connector


On my Orion Tr 18A dc-dc smart charger, there 2 separate negative connector on both input and output. I am about to install it on a travel trailer and I need some help with wiring from the 7-way connector - there are 2 10awg wires, white (ground) and black(starter batt/alternator). which way should I connect the ground wires:

1. 7-way white -> Orion input negative, Orion output negative -> trailer 12v ground bus bar (Batt)

2. 7-way white -> trailer 12v ground bus bar(Batt) -> orion input negative/orion output negative.

Actually I am not very confident about either of these ways. For 1, there are other wires for brakes, lights - if the ground is 'isolated' buy Orion, I am not sure if these wire would provide proper voltage. For 2, not sure if I am supposed to connect the 2 neg connectors on Orion directly.

Thanks in advance!

hovr asked

0 Answers

Charging Starter and Bow thrust battery from Leisure battery system what size Orion Tr

Hi All , I am living off Grid on a Narrowboat and have a big solar system that supplies pretty much all my power needs 95% of the year and I have back up Gen for the rest . I dont therefore Run my Engine much so except We do move the boat every 2 weeks briefly for service . This means the Starter and Bow thrust batteries get used a little but dont get a proper recharge so are sitting in PSOC most of the time sulphating . I would like therefore to syphon some power from my Solar system ( I have plenty to spare ) into the starter and bow thruster batteries until they are topped off . Currently they are Sealed LA batteries but when replaced will prob be AGM so I dont want to overcharge them . Is Orion Tr good for this ? and if so what size is best for 2 x 100Ah Sealed LA or AGM batteries , they wont be high DOD so prob dont need a very high current . Also what is difference between Isolated and non Isolated and which is best for this application ?

In addition what does the smart bluetooth tell me ? will it tell me SOC of the starter and thruster battery or will I need a Smart Shunt for that ?

Sorry for all the Questions

Simon Phillips asked

0 Answers

which orion dc to DC


I am updating the leisure electrics in my VW T6 Euro 6 to a lithium system. I am replacing everything with Victron apart from the CBE Fused distribution box and the only thing I am stuck on is the DC to DC charger. I will be using a single 100AH lithium leisure battery. I am presently using a Ring RSCDC30 combined 30 Amp DC DC Charger/MPPT which has the positive out feeding to the CBE unit then from there to a busbar. Although programmable I have been advised against using it for lithium so will be replacing with a Victron MPPT and a Victron Orion unit. Can anyone advise which Orion unit is best suited for use with a VW T6 Euro 6. Also do I need isolated or non-isolated.

many thanks

tcummins857 asked
hyvast commented ·

1 Answer

Configuring Orion-Tr Smart DC-DC Charger Isolated with MB Sprinter Smart Alternator

Hi, I have installed an Orion-Tr Smart DC-DC Converter/Charger (configured as an isolated charger) in my 2015 MB Sprinter which has a smart alternator. The house batteries are 2 X BattleBorn 100Ah LiFePo batteries. BattleBorn recommends to set chargers to the following settings:

Charge voltage ‘absorption’: 14.4V

Charge voltage ‘float’: 13.6V

However, at those settings the Orion-Tr Smart DC-DC Charger never charges the batteries. But if I change the settings to 13v and 12v then it does charge the batteries under Absorption charge (see attached pics.) I'm getting 14.2v on the input line when the engine is running.

Q: What should all the settings below be set to?

My current configuration:

Under voltage shut down: 13.1V

Under voltage restart: 13.3V

VLockout: 10.4V

VLockout Restart: 10.5V

Charge voltage ‘absorption’: 13V

Charge voltage ‘float’: 12V

Thank you so much in advance!

Note: I installed an isolated version because the non-isolated was not in stock.



davidcolemandc asked
davidcolemandc commented ·

3 Answers

4 season RV solar system batteries in series or paralel? -12V or 48V

I want to plan a solar system for Mercedes Sprinter or other converted RV.

On the roof can be mounted 3x solar panels in my oppinion (+vents) for Medium Wheel Base (MWB) and 4x solar panelson a Long Wheel Base (LWB) or even Extended Long Wheel Base.

Similar is the simutation for Fiat Ducato, Citroen Jumper, Peugeot Boxer, Iveco Daily, VW Crafter.

Those solar panels, will have enough power to fill up 2x or 3x battery, probably gel or agm, with 100Ah or 200Ah ( depends on the budget) .

I suse at AT DIFFERENT car a vacum cleaner 1400W and with a 2500W not sinus inverter (not from Victron) It is very handy to clean up my car! Also used a 750W angle grinder, a 700 or 900W rotary hammer and so on. Now it seems I can't handle those devices that inverter which are using 1700W from pure sine wave and all this powered from my running engine : 14.4V and 55AH battery and a small alternator: around 90A. But it is just great to have tools to repair your car or do some mobile workshop jobs ocasionally.

I would like to use a coffe machie: around 1400W-2000W usually, maybe a washing machine 700-1200W, maybe ironing, instant cooking around 1500W , so 2000W sine wave it would be enough, but 3000W for sure and not need huge capacity, just around 3000Wh, that could hadle propably a pizza cooker too. At 12V battery it means: 3000 / 12 = 250A battery. ( but no less). So 4 x 200Ah for sure it is enough and 2 x 200 A h for sure not if I use a high end laptop min 8h /day ( around 640Wh/day)

The Mercedes Spinter has an option to buy it with 190A alternator, but about other vans I am not sure. 190A x 14.4V => 2736W charging power at max. To fill up the 3000Wh with losses propably it would take 1.5h, max 2h running on idle or drive mode, which is fine for me.

As we know in the winter we have fewer sunny days, and a lot less, fewer daily hours and even less usable hours for charging. Maybe 2 or 3h in a good day? And solar panels can have 10-15% of they max power, so I must use the alternator charging mode at the base. (3x solar, at 15% of 270W x 3h = 364Wh)

There are 2 possibilities on which I am hesitating: connect batteries in paralell: 12V or in series 36/48V?

If I do in paralell 3 or 4x batteires I have to do the same with solar panels, I think, but for sure I need to have battery balancer ( how many do I need and how much they will costs?). I am not sure how good are those batteries connection for 4-5 year for sure one of they will be weaker than others and we be an internal consumer. Havinig it in paralel I neep the 12V, but that means it is required to have wider cables, much more heat production and much more risk to fire. I know there are fuses and you know those can fail, like any electrical equipment. The advantage of paralel connection it would be easier to charge from the alternator.

If I do the connection of batteries in series I will have 36 or 48V and lot less Amper, lot less diameter of cooper wire needed to use, lot less heat, of course solar panels would come also in series. The backside of this now the alternator can't chage it, need a DC/DC converter from 12V to 36V or 48V. - which I don't know how much does it costs again. Other thing it is if I want to use a device projected for camping, hence 12V and in rare case 24V I can't, because I have 36 or 48V. For example a 12V water pump probaly is needed for sink or maybe others to fill up the water tanks.

I think that pure sine inverter of 3000W willl be an expensiever item, and for that should be easier to work from 36 or 48 compared to 12, hence should be cheaper again (with something.)

So how is better technically to connect those batteries in my case and which is cheaper with how much?

As I how I see the prices:

Victron Energy MultiPlus 3000VA 12-Volt Pure Sine Wave Inverter 120 amp Battery Charger: 1284 usd

Victron Energy MultiPlus 3000VA 24-Volt Pure Sine Wave Inverter 70 amp Battery Charger, UL-Certified: 1427 usd, so surprise: this is the expensiever one with a few percent.

(it seems this inverter has the charger part too!)

Victron Battery Balancer: 65 usd

Or should I use a 24V system instead of 48V? according to this: https://community.victronenergy.com/questions/41792/how-to-charge-a-48v-system-from-a-12v-vehicle-alte.html

Or simply use a different 230V generator and no solar panel at all? - https://www.eevblog.com/forum/chat/48v-alternatorgenerators-for-automotive-use-do-they-exist/

Somebody put an inverter to alternators and made from 12V the 230V and on that way charged the 48V: https://community.victronenergy.com/questions/71403/charging-48v-batteries-from-alternator.html

So many requests for 48V, I don't undertant why Vicron doesn't offer a solution! Should I make it? :)

I just found out it is a 6V battery with 240AH from Victron, connecting in series it will be 24V bus!

Even more: https://community.victronenergy.com/questions/76200/gel-agm-hybrid-batteries.html

hakogef asked
offroadflow answered ·

1 Answer

Best option for charging a secondary 12V battery bank from a primary 48V battery bank


I have a 48V, 440Amp battery bank for the electric engine in my sailboat. I also have a 12V, 200Amp buffer battery for my house bank.

I own the following Victron equipment:

12/12-30 DC-DC Smart Charger

48/12-30 DC-DC Converter

Before I connect this and possibly damage the equipment and battery banks, I thought I would check with the forum. Should I connect the 48V bank to the converter, the converter to the charger, and then the charger to the house bank?



ftlsailor asked
JohnC answered ·

1 Answer

Decide ‘isolated’ or ‘non-isolated’ for Orion?

For charging a 24v bank (bow thruster) from the 12v starter bank I’m looking at the Orion-Tr 12/24-15A (360W). But now I have to choose between isolated and non-isolated. Am I correct that the isolation is about the ground wire? But what if both my banks have their negatives connected (via the hull) already? Does it matter for the Orion?

ed-kok asked
alan commented ·

3 Answers

Non-Isolated vs Isolated Orion-Tr Smart DC-DC Charger

Hi all,

I have a VW Caddy van that I’m converting to a camper. It’s a modern one with a silly euro 6 alternator and some I’m on the understanding that I need an Orion Smart DC to DC charger, specifically the Smart one to charge my Victron AGM battery (in time this may become a lithium).

If I’m planing on using the chassis as a ground for both the starter battery and the leisure battery combined, do I need the isolation?


cwoody asked
mattr edited ·

2 Answers

DCDC and MPPT charge conflict

Hi i have a dcdc 12/12/30 and a 100/20 solar controller, the solar controller works fine without the car running, when the car is started the DCDC kicks in but at a reduces amp input, for example solar input 10amps dcdc running total showing 20amps so the dcdc only adds an extra 10amps, i also have a BMV712 connected, maybe the setting on all three are conflicting?

romual30 asked
romual30 answered ·

2 Answers

Buck Boost 100amp Not Charging.

Hi All,

so i have fitted over ten of these units to brand new merc vitos over the last 6 months, how ever i have run in to an issue with one of my latest installs.

the Buck boost is fitted to a connect 6 bus bar via a fuse (fuse tested and fine ) to charge 5 x 12v LiPo4 victron smart batteries totalling 1000ah

all programmed the same as all the others, it is set to 75amp at 14.2v with the victron Lithium ticked.

basically, it starts charging as it should, and checked outputs on TSconfig with Buck running and it is kicking out 75amp on the screen however it is not actually giving any real output!

also another weird symptom is that when it is connected it will intermittently cause the engine to cut whilst driving. if i remove the input fuse to the buck this symptom does not occur.

has anybody else come across this issue?

the vito alternator is a 190amp.

as a general rule they usually give a % increase of around 8% per hour when charging.

stevemarston asked

0 Answers

How to measure two DC Inputs On CCGX

I am looking to install a Victron system on my RV that will be using a third-party DC-DC charger to charge 48v house batteries from the vehicle's 12v alternator. If I were to connect this charger through a dedicated BMV battery monitor (with a second one for the system's DC loads), is there any way to have one show up as an "alternator" input on the CCGX display screen?

I know I could connect it through the BMV-700 and presumably just have the CCGX show it as power flowing from the "DC loads" box to the battery. My primary concern is ease-of-use for the end user, so I would greatly appreciate any way to configure thte CCGX for this display.

chase-martin asked
48v-on-56north commented ·

3 Answers


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