Electrics: Firmware update for the Victron Orion XS – it now charges in reverse in an emergency

Normally, in the Orion XS, power flows from the starter battery to the service battery. When the engine is running, the alternator supplies the starter circuit, and the B2B charger regulates the appropriate current for the service battery from this. We have already seen this principle in the Orion XS 12/12-70 with a charging current of 70 amps as described. The new firmware is now said to allow the charging direction to be reversed temporarily.

15 minutes to recharge, then attempt to start

If the starter battery is too weak to start the engine, you can now tap the starter battery charging icon in the VictronConnect app. The Orion XS will then reverse its charging direction for 15 minutes. This is followed by a five-minute pause during which the charger is switched off. The engine should be started during this time. Victron describes the function as ‘Emergency reverse charge’, i.e. reverse charging for emergencies.

The current remains limited in this process: it is capped at either the set current limit or half the rated current of the respective device, whichever is lower. If the voltage of the service battery drops too low, the Orion XS automatically reduces the recharge current. The starter battery is charged to a maximum of 14.4 volts. For the Orion XS 1400 with a 24-volt starter battery, the limit is 28.8 volts.

Only when forward charging has stopped

Reverse charging cannot be activated during the normal charging process. It only becomes available once the Orion XS has finished forward charging, for example because the input voltage is too low or the unit has detected that the engine has been switched off. According to Victron, the function should remain available even when ‘Remote-off’ is active.

This is particularly useful for boat owners when a flat starter battery leaves the diesel engine inoperable whilst moored in a bay. This is provided that the service battery is still able to supply sufficient power. Furthermore, the cause of the flat starter battery should be investigated.

Update via the app or remotely

You will need Orion XS firmware version 1.15 and at least version 6.43 of the VictronConnect app. The update can be installed via the app or via the VRM portal. With the versatile Orion XS 1400 for 12- and 24-volt systems Before using the emergency charging function for the first time, you must specify whether the starter battery operates at 12 or 24 volts.

Book recommendation

Theory and Practice of Vehicle Electrical Systems covers the electrical system, from the battery through to charging technology and troubleshooting. For boat owners who wish to install a B2B charger or identify the cause of unexplained discharge from the starter battery, the chapters on DC distribution, engine electrics and maintenance are particularly helpful.

Have you already made provision on board to support the starter battery from the service battery bank if the engine fails to start?