This Victron Orion-Tr Smart isolated review covers the DC-DC chargers Victron makes for systems where the input and output must stay electrically separate. They give a 3-stage charge (bulk, absorption, float) from a starter battery to a service battery. Models come in 12V, 24V and 48V input and output versions, from 220W to 400W. Each has 200V DC galvanic isolation between input, output and case.
Electrical work can be dangerous: follow the manual, fuse and size every cable correctly, and use a licensed electrician for anything connected to household wiring.
Victron Orion-Tr Smart Isolated Review: Key Models
| Model | Input range | Continuous current at 40°C | Power at 40°C | Efficiency |
|---|---|---|---|---|
| 12/12-18 | 8-17V | 18A | 220W | 87% |
| 12/24-10 | 8-17V | 10A | 240W | 88% |
| 24/12-20 | 16-35V | 20A | 240W | 88% |
| 24/24-12 | 16-35V | 12A | 280W | 89% |
| 48/12-20 | 32-70V | 20A | 240W | 87% |
Source: Orion-Tr Smart DC-DC Charger Isolated manual. 360W to 400W models, such as the 12/12-30, are also available.
Shared specs: standby draw under 1mA, output adjustable (10-15V on 12V output), screw terminals up to 16mm² (AWG6), operating range -20 to +55°C (derating 3% per °C above 40°C), 1.3kg, 130 x 186 x 70mm.
What We Like
- Galvanic isolation. Input and output can have separate negatives. That helps on boats and in vehicles where the house and chassis grounds must stay separate.
- Voltage conversion. 24V truck to 12V camper, or 12V to a 24V house bank, in one unit.
- Engine-running detection. It switches on only when the alternator is charging, so no ignition wire is needed in most vehicles.
- Bluetooth and VictronConnect for settings, presets and remote on/off control.
- Parallel units. Victron allows unlimited units in parallel for more current.
What to Watch
- Lower efficiency. At 87% to 89%, it wastes more energy as heat than the Orion XS at 98.5%.
- Modest current. 18A to 30A on 12V is slow for a large lithium bank. Two or more units, or an Orion XS, may suit better.
- Heavier and bigger than the XS: 1.3kg versus 0.33kg.
- Undervoltage cut-off is low. The 12V models shut down at 7V and restart at 7.5V on the input, so set engine detection correctly to protect the starter battery.
Who It’s For
Boat owners who need isolated DC systems, anyone converting between 12V, 24V and 48V, and vehicles where the house and chassis grounds must stay separate. For a plain 12V-to-12V van with a large lithium bank, the Orion XS gives more current per dollar.
Settings to Check in VictronConnect
- Charger or power supply mode. As a charger it runs bulk, absorption and float. As a power supply it holds a fixed output voltage, which is useful for long cable runs to 24V gear.
- Battery preset. Choose a lithium or lead-acid preset, or enter custom voltages.
- Engine shutdown detection. This turns charging on only when the alternator is running, so most vehicles don’t need an ignition wire. Adjust the thresholds for smart alternators.
- Remote on/off. A lithium BMS can use this to stop charging.
Setup and Troubleshooting Tips
- “It only gives 18A.” That’s the rating of the 12/12-18 at 40°C. For more current, Victron allows units in parallel, or use a 12/12-30 or an Orion XS 50A.
- Gets hot. At 87–89% efficiency, an 18A unit turns roughly 30W into heat. Mount it with free airflow; output derates 3% per degree above 40°C.
- Shuts off at low input. The 12V models cut out at 7V on the input and restart at 7.5V. Long, thin input cables drop voltage under load, so size them for the run.
- Charges with the engine off. Engine detection thresholds may be too low for your vehicle. Raise them, or use an ignition signal on the remote input.
- Grounds joined by accident. Isolation only helps if the input and output negatives are wired separately.
Charge Time Worked Examples
Divide the amp-hours you need to replace by the charger’s continuous current to estimate driving time.
| Battery and starting point | Charger | Approx. drive time to full |
|---|---|---|
| 100Ah LiFePO4 from 20% | 12/12-18 (18A) | about 4.5 hours |
| 100Ah LiFePO4 from 20% | Two 12/12-18 in parallel (36A) | about 2.2 hours |
| 200Ah 24V bank from 50% | 12/24-10 (10A) | about 10 hours |
| 100Ah 12V bank from 50% | 24/12-20 (20A) | about 2.5 hours |
Lead-acid batteries add a slower absorption phase at the end, so expect longer times for AGM or flooded banks.
Input Current and Cabling
The input side draws more current than the output delivers. A 12/12-18 delivering 220W at 87% efficiency takes about 19A from a 13.5V starter circuit. Size the input cable for that current over its full length to keep voltage drop low, and fuse both input and output near their sources.
The 48/12-20 also works as a step-down converter in 48V systems, powering 12V lights and pumps from the main bank.
Worked examples are arithmetic estimates from the published ratings above, not test results. Real numbers depend on temperature, cable runs, battery state and load.
Victron’s Orion-Tr Smart isolated product page has the full datasheet and manual downloads.
FAQ
Isolated or non-isolated?
Choose isolated if the negatives must stay apart or you need to convert voltage across separate systems. Otherwise, non-isolated is fine.
Can it charge lithium?
Yes. It works with lead-acid and lithium batteries, with presets and custom voltages in VictronConnect.
How many can I parallel?
Victron allows unlimited units in parallel.
Can it charge a 12V house battery from a 24V truck?
Yes. The 24/12-20 takes a 16–35V input and delivers up to 20A to a 12V battery, with isolation between the two systems.
Sources: Orion-Tr Smart DC-DC Charger Isolated manual and product page (victronenergy.com); Springers Solar, “Simple DC-DC Charger Setup | Victron Orion Wiring & Programming”.
Sources: Orion-Tr Smart DC-DC Charger Isolated manual and product page (victronenergy.com, accessed Oct 2026).
Related: EcoFlow Delta 3 Max Van Life Leisure Battery, LiTime 12V 50Ah LiFePO4 Battery Review, Pro Chaser 400W Car Power Inverter Review, plus the Victron Energy Guide