orion dc-dc Image

orion dc-dc

Existing Lead Acid adding extra Lithium with Bidirectional DC-DC Orion TR Smart



I have an existing FLA house battery bank (4x 12v 115Ah) charged by alternator and solar on narrowboat. The starter circuit is separate with dedicated battery and alternator.

I would like to add a lithium to increase capacity to the house bank.

I have seen people just adding a smart Lithium to FLA in parallel relying on Lithium BMS, which I am not that happy with - or will this work?

I have also read on this forum of an idea using two Orion TR Smart 12/12-30A in opposite directions with a manual switch to control direction on charge, either to charge lithium or discharging lithium to lead when not charging - which sounds like it does what I want, apart from the manual switch - this surely can be done automatically.

I have also seen the BOS LE300, which appears to do what I want, but very expensively.

I would like to add my own 100Ah Lithium, and have a module that manages the charging and discharging the Lithium correctly.

Would this be equivalent to a bi-directional Orion TR Smart?

Does this exist?

Alternatively - could I just move all the load to come off the Lithium and use a Orion TR Smart to charge Lithium from Lead/Alternator, so removing the need to be bi-directional. Can a Lead charge a Lithium without the alternator or solar putting in charge? I don't think I could do the opposite way around and charge the Lithium side from the alternator due to overheating and BMS shutoff potentially killing the alternator?

Or any other suggestions?

Thank you

dclj asked
James Hooper edited ·

3 Answers

125amp alternator - how big Orion dc-dc?

I have a boat with old lead acid batteries that I want to upgrade to 12v, 4 * 200ah lifepo4 batteries = 800ah.

I also have a 125a alternator on my yanmar diesel engine.

Can I just install a single victron 30 amp dc dc charger on a 125 amp alternator?
Where will the remaining 95 amps go?
How do i set-up my fuses?
If i put a 40 amp fuse between alternator and dc dc charger, it will blow very quickly?
Do you need to oversize your DC-DC converter compared to the alternator?

Its a sail boat, with solar panels, so I dont plan on using the engine that much. And orions are pretty expensive when i need 4.

Thank you!

anonymous37389 asked
trevor-bird edited ·

5 Answers

Orion standby current? Does it need to be turned off?

I have a boat, with starter battery and domestic bank. I plan to use a non isolated Orion 12 12-30 to charge the domestic bank. The starter battery can be charged in 3 ways: alternator, solar or shore power. Is there any reason why the Orion should not be left on ALL the time so that if the starter battery voltage is high enough it passed power though to the domestic bank? Clearly the cut off needs to be set high enough that the started battery does not discharge. And finally if that condition is not met what is the Orion consuming? Is this the 1mA standby current in the data sheet? Thanks.

steves asked
steves answered ·

2 Answers

Orion Tr Smart parallel diagram and/or documentation location

Does anyone know where to find documentation about wiring two Orion TR Smart 12/30 units in parallel to provide a 60+ amp charge?

I’ve been scouring the Internet to no avail. I’ve also read the online TR manuals.

Of course, I can take a guess at wiring them in parallel and configuring the app settings….but would much prefer some documentation.

Any help is appreciated. Thanks.

jeepcamper asked
kevgermany commented ·

1 Answer

Which DC-DC Charger to choose


I'm looking at setting up a DC-DC charger in my Subaru Forester for my leisure battery that is purely used to keep my Engel going overnight in the car.

I have The Rover Lithium 70Ah Power Station


  • 70AH Lithium NMC Battery
  • Cell Chemistry: LiNiMnCoO2 (NMC)
  • DC Charger: 14V 7A (Max 110W)
  • AC Charger: 16.8V 5A

My Questions are:

  1. Are the DC-DC chargers compatible with Lithium NMC battery’s?
  2. Which Model DC-DC charger would be compatible to charge my Lithium Battery?

ben-rolfe asked
kevgermany answered ·

2 Answers

Upgrading my power management system to Victron and have questions

Hi All,

I have been running a 125 aH AGM in my camping rig (for coach battery) for five years and it finally gave up the ghost. This setup was only good for about 36 hours…so I ordered a matching pair of the same battery for a total of 250 aH.

Since I need to build storage for the additional battery, it’s time to upgrade my charging system. I’ve been doing a ton of research on Victron products and think I’m getting close.


  • Two VMAX SLR125 125 aH AGM batteries in parallel for a 12v system (both new)
  • Usually use less then 4 amps when boondocking (for a bedroom fan at night and fridge at all times)
  • Will be adding some LED lights for night use
  • Jeep has 160 amp alternator
  • Previously used a National Luna battery box and NOCO Gen2 (10 amp per bank) for shore power and charged straight off the alternator

Battery Specs:

  • Specifications:

    Nominal Voltage 12V

    20Hr Capacity 125Ah

    RC (min) 260

    Energy (kWH) 1.7

    Terminal Posts 8mm

    Dimensions 12.9"w x 6.8"d x 8.5"h/8.7th**

    Weight 75lb

    Charging Current* 8A-35A

    Charging Voltage 14.4V-14.9V

    Float Voltage 13.5V-13.8V

Plan to order:

  • Victron Blue Smart IP22 12/30 for shore power
  • Orion Tr Smart DC-DC 12/12-30 for charging on alternator
  • Victron shunt (TBD)
  • BMV-712 monitor (TBD)
  • Probably a Victron near-battery temp & voltage sensor (temp drops below freezing here in winter)

As you can see, this is a simple system and I’m only trying to add power for additional camp days. Solar charing is off the menu until I purchase a new roof top tent that will accommodate solar panels. For now, alternator and shore power will be the only charging methods.

I’m hoping that knowledgable people here can check my work and suggest any changes if I’m on the wrong track. There are no Victron dealers or installers in my area, and I worked in the car stereo field when young. I can handle the wiring, but it’s bee a while since I’ve tackled something so intricate.

Also, I’d like to make sure that all Victron components will handle a 200 aH LifePo4 bank in the future when these AGMs die again.

Am I correct in choosing a 30a charger for home and a 30a DC-DC for alternator charging?

Many thanks for any help!

jeepcamper asked
jeepcamper answered ·

3 Answers

Alternator and DC to DC charger


Is it possible to connect an Orion TR Smart DC to DC charger directly to an alternator and then to a lithium battery bank in a boat?

I do know that the often recommended solution is to connect via the start battery and/or installing an external regulator.

So those suggestions and other suggestions as to why I want this solution is not relevant.

I only would like to know if it is possible or not. If not, why?

I have tried to reach out to several Victron distributors, seen several online videos (reputable like Jeff Cote) and in particular the online webinar from Victron 22 Jan 2021.

In the latter there is a drawing (at 19:45) that indicates that it is possible, but the voice-over is not fully clear to med.

Hope someone could help, much appreciated!

Best regards


klohre asked
klohre answered ·

2 Answers

Victron Ladebooster 18A fiept

Hallo zusammen, in meinem VW T6 Bulli ist eine Lithiumbatterie von Liontron 100Ah verbaut. Es wurde eine Victron Orion 12-12 18A verbaut, der die Lithiumbatterie auflädt sobald die Zündung eingeschaltet wird. Jedoch fiept das Gerät sehr laut für einige Sekunden, mal fiept es nicht, mal für 5-10 Sekunden. Das passiert auch bei der Start-Stopp Automatik. Kennt das Phänomen jemand ? Ich habe den Ladebooster bereits gegen ein neues Gerät getauscht. Gleiches Verhalten. Ein Bekannter von mir sagte mir dass ich für meinen Bulli (Dometic Kühlschrank, Küchenzeile, wohnraum beleuchtung) lieber einen Ladebooster mit 30A nehmen sollte. Denkt ihr das könnte der Grund für das Fiepen sein ?

elkaine asked
kevgermany answered ·

1 Answer

DC-DC overcharging batteries?

I have lithium batteries fitted to our motorhome. Have a Victron dc-dc charger that governs the charging from the alternator. When the batteries are fully charged and I’m driving, I’d understood that the batteries wouldn’t be overcharged due to the management system and the dc-dc charger. Why then do some people fit isolation switches to turn off the dc-dc charger when driving?

ingwe asked
klim8skeptic answered ·

4 Answers

Orion-Tr 12/24-Volt 5 amp 120-Watt DC-DC Converter output to feed a 24V solar MPPT controller.

Can I use the 12/24-Volt DC-DC Converter output (24V) to feed to feed the MPPT controller input ( solar panel input) ? Here is my problem , I would like to recharge a 100A auxiliary Bat in my car using the 12V socket. A fridge is connected to the secondary bat . When the fridge kick in, the current draw between both batteries (via the 12v socket) is too much (> 20V) and melt the socket. I don't really fully understand it but roughly , when the fridge kick in, the Voltage of the Aux bat drop and too much current goes to the 12v socket. All the current limitators I could test just blowed. I need to find an elegante solution. Right now I am running a small inverter (in the 12v socket) to power a 120V/3A battery charger which charge the Aux battery. It works but I don't want to run a power inverter. The Aux battery has a built-in solar controller. I would like to use the Orion-Tr 12/24-Volt 5 amp from my 12v socket to convert 12V (Orion-TR 12V input) -> 24V (Orion-TR output) feeding the input of MPPT controller (basically replacing the solar panel). This model is putting 5amps as the output but the doc does not say how much current it is drawing on the input side. Remember my problem is at the 12V socket level which melt (on my Subaru) when I use too much current (when the fridge kick in).

Any thought ?

Thanks for any help.

cguilbert asked
kevgermany answered ·

1 Answer

Need to remove existing automatic charge regulator?

Hi. I’ve just purchased a Lance truck camper as well as the 12-12/30 DC-DC charger, which will feed a LiFePO4 battery. The Lance came equipped with a Blue Seas Battery Link Automatic Charge Controller, which in effect acts as a battery isolator between the truck and camper. Can I leave the Blue Seas ACR in place without conflict? It would be upstream of the Victron DC-DC.

orourkmw asked
kevgermany answered ·

1 Answer

buck boost stops output current when target voltage is reached

installed 100amp Buck- Booster and programmed output at 14.6 volt 100 amp output for 400ah lithium battery's as soon as it reaches set output voltage it stops putting out amps, any ideas

failsafe asked
snoobler answered ·

1 Answer

Orion tr 12/12 30A drawing power instead of charging when in charger mode

Hi Guys,

Cant for the life of me figure out what’s going on here. Shunt is showing that the Orion is drawing charge and the battery % is dropping while it’s running instead of charging

Thanks in advance for your help.

I don’t have a smart alternator. vehicle 2018 Citroen relay.

Shunt definitely wired the corrected way round and all readings are normal.

checked that the input and outputs are definitely correct.

Victron Blue Smart working perfectly and showing positive values while charging.

checked the earths and they are both linked

the breakers do have a battery and load side written on them. battery side is wired to starter battery for both of them.







jacko539 asked
klim8skeptic commented ·

1 Answer

Orion not charging

Hi, I had a marine installation with a simple alternator feeding a lead acid starter battery and a VSR feeding a lead acid house battery, all negatives running to a 500amp Victron Shunt and working well.

I swapped out the LA house battery for 280Ahr Lifepo4 and swapped the VSR for an Orion 12/30 which charges at 20amps for about a minute and the drops to 1amp or less on a battery with a Low state of charge warning running. Battery is about 12.7v, charger shows input of 14.3 and output of 14 but shunt shows 12.7. wires are the same guage as previously and the cable run lengths didn't change... what settings have I not used correctly?

petepresto asked

0 Answers

Ignition protected What does this mean?

Orion IP67 24/12-20 DC-DC converter, Non-isolated, what does it mean when it says it is ignition protected, does this mean when its hooked up to my Vehicles starting system that it is not affected by the battery drain (voltage drop) when I'm starting my car?

I hope my ? makes sense


finn asked
trevor-bird answered ·

1 Answer

46 Posts
44 Users

Topic Experts

There are currently no experts identified for this topic. Can you answer questions in this topic area? Community members who provide answers that are marked as correct earn reputation and may become recognized as topic experts.