Orion-Tr Smart does not charge the battery

A working charger lights or flashes its LEDs and connects to VictronConnect. The Bluetooth circuit is powered by the battery connected to the input — without input voltage both LEDs are off. If nothing lights up:

• inspect the enclosure and terminals — mechanical damage is a likely cause according to the manual;
• check for burn marks and a burnt smell — this is also a likely cause. The unit is potted, so a slight smell while charging is normal when it warms up;
• measure the battery voltage directly at the charger terminals with a multimeter — this rules out cables, fuses and switches in the path from the battery.

The manual recommends starting by checking whether the app gives the reason charging is disabled (the “Off reason” field or the message “Charge is disabled due to: …”).

If the charger is charging (Bulk, Absorption or Float) and the battery is still not full, go to steps 6 and 7.

The minimum for the charger to work is a wire bridge between terminals L and H. Check whether the remote plug is inserted, and with a bridge or simple switch — whether there is continuity between L and H. The manual gives four recommended wiring methods:

• a) a switch between L and H (on when the impedance between them is below 500 kΩ);
• b) a switch between the positive of the input battery (starter battery) and terminal H (on above 3 V);
• c) a switch between terminal L and the negative of the input battery (on below 5 V);
• d) control from the BMS — in the isolated version via the isolated remote wire, in the non-isolated version via terminal H.

Terminals L and H withstand ±70 V DC. If the remote connector is controlled by the BMS, check whether the ATC connection (charge permission) is working. The BMS may also have intentionally blocked charging — see “BMS has cut off charging”.

During installation, the manual says to disconnect remote first (remove the bridge or unplug the connector), configure the unit in VictronConnect and only then reconnect remote — it is what starts the charger.

In charger mode, Orion-Tr Smart detects engine running from alternator voltage alone — no additional sensors are needed. A conventional alternator gives a constant voltage (e.g. 14 V), and a smart alternator gives a variable one, from 12.5 V to 15 V; it varies most in regenerative braking systems. Factory settings for the 12 V input (multiply by 2 for 24 V, by 4 for 48 V):

How it works: when the input voltage drops to the shutdown threshold, the charger reduces the current so it does not fall any lower. If the voltage stays below the threshold for more than one minute, it assumes the engine is stopped and stops charging. Current flowing in the input cable lowers the voltage measured by the charger — input cables that are too thin or too long therefore make it reach the threshold sooner (step 6).

• Does not start charging — the start threshold is set too high for the alternator, which never reaches it. Lower the start threshold and make sure the alternator allows it.
• Stops charging too early — the shutdown threshold is set too high. The operating description in chapter 5 shows that lowering it helps; the table in chapter 7.2 says to “raise” it here — this is an inconsistency in the manual. The shutdown threshold keeps the starter battery charged and creates hysteresis relative to the start threshold; according to the VictronConnect manual, a difference of at least 0.2 V between the thresholds is usually used (for 12 V input).
• Ignition controlled — a voltage above 7 V at the L terminal forces charging regardless of engine running detection (for example from the ignition switch or an engine-running signal from the CAN bus). This does not replace the remote function — the connector must be wired using method a), b) or d) from step 3. After the ignition is switched off, the charger returns to engine-running detection rather than switching off.
• Engine running detection disabled (“forced charging”) — the charger draws current from the starter battery even with the engine off. In this case, only the input voltage lock-out protects it (step 5), so do not set it too low — according to the manual, in most 12 V applications 12.5 V is a sufficiently low threshold.

Engine-running detection works only in charger mode. The mechanism described applies from firmware v1.05 — you can check the version in VictronConnect (Settings → three-dots menu → Firmware).

Input voltage lock-out is the lowest voltage at which charging is allowed — below it, charging stops immediately and resumes once the restart threshold is exceeded. Factory settings for 12 V input: in charger mode, lock-out 12.5 V and restart 12.8 V; in power supply mode, 10.5 V and 12 V. According to the VictronConnect manual, a difference of at least 0.5 V between lock-out and restart is usually used. The manual’s solution: ensure the input voltage is above the restart threshold or disable the lock-out in settings — but with engine-running detection disabled, the lock-out is the only protection for the starter battery.

When setting the lock-out, the manual gives two criteria:

• Lowest alternator voltage — a smart alternator can briefly drop below 12.5 V, for example during acceleration. If charging should continue then, the lock-out must be set below that voltage.
• Voltage drop on the input cable — the lock-out must not trigger before the charger has time to reduce the current: lock-out threshold ≤ shutdown threshold − cable voltage drop. In the manual’s example (5 m to the starter battery, 16 mm² cable, about 1.1 mΩ/m, i.e. 11 mΩ for 2 × 5 m, current draw about 35 A for the 12/12-30 model), the drop is about 0.385 V. The manual subtracts it from 13.3 V, although the shutdown threshold in this example is 13.1 V — at 13.1 V this gives about 12.7 V.

Regardless of this, the charger switches off at very low input voltage: 7 V (restart 7.5 V) for 12 V input, 14 V (15 V) for 24 V and 28 V (30 V) for 48 V.

• Check whether the cables are damaged, connections are loose, lugs are badly crimped, and the battery fuse has blown. Is the insulation stripped to the correct length, and are the terminals tightened to the correct torque — 1.6 Nm, held for at least 5 seconds? Never tighten less.
• Use flexible multi-strand copper cable: a single wire must be at most 0.4 mm in diameter (0.125 mm²); a 16 mm² cable should have at least 122 strands (Class 5 or higher). Thicker wires give too little contact area — high contact resistance leads to severe overheating and eventually fire. The maximum terminal size is 16 mm².
• Burn marks on the terminals or melted cables or connectors — the manual says to replace the device; this type of damage is usually not covered by the warranty.
• VictronConnect shows a higher output voltage than you measure at the battery? At high current this is normal, but the same symptom can be caused by a poor connection between the output and the battery — keep the resistance of all connections as low as possible.
• Installation: vertical, terminals down, on a non-flammable surface, with at least 10 cm of free space above and below the device, close to the battery, but never directly above it. The charger has overtemperature protection and reduces output at high temperature — above 40 °C by 3% for every degree (operating range −20 to 55 °C).

Minimum cable cross-sections by length and external fuses from section 4.2 of the manual. Selection rules: DC cable cross-sections and fuses.

Wrong battery settings may cause the charger to switch to Absorption or Float too early and the battery will not charge fully.

• Check the absorption voltage in the Battery settings and set the value recommended by the battery manufacturer. The preset also sets the Float voltage, Bulk time limit, re-bulk threshold and absorption time — each of these values can be changed.
• Make sure charger mode is selected — power supply mode does not use the charging algorithm, and the output voltage may be set too low.
• Absorption time: for lead-acid batteries, adaptive (short after shallow discharge, longer after deep discharge); for lithium batteries, fixed — 2 hours as standard. With adaptive time, you set the maximum time (at least 30 minutes); with fixed time, you can set any value, even 0.
• In Float, a new charging cycle starts when the battery voltage has been below the re-bulk threshold for at least one minute, for example under heavy load.

If the STATUS screen shows “Input voltage lock-out”, go back to step 5; if charging stops and starts, go to step 4.

You can read the code in VictronConnect. The Orion-Tr Smart manual describes five codes:

For the current list of codes, the manual refers to the common Victron charger code list — you can find descriptions of all codes on the charger and MPPT error codes page.

• Blue LED off — no input voltage (restore power), Bluetooth permanently disabled in VictronConnect (this setting cannot be undone), or set to “Enabled for 30 seconds”: Bluetooth then works only for 30 seconds after power-up — disconnect and reconnect the input cable and connect within 30 seconds. If none of these fits, the device may be faulty — make a warranty claim.
• Blue LED flashes every 0.8 s — a connection may already be active. Only one phone or tablet can be connected at a time; if Orion is greyed out in the app, another device is connected.

Other connection problems: “VictronConnect does not connect via Bluetooth”.