Victron Shunts & Battery Monitors
Victron SmartShunt and BMV battery monitors measure state of charge precisely, so you always know how much power you have left.
Where to fit a shunt for accurate readings
The shunt has to sit in the negative cable between the battery and every other connection on the boat, not just some of them, or the current it measures will not represent the whole system. That means the battery negative terminal connects only to the shunt, and everything else, from bilge pumps to the engine block earth, connects to the shunt's load side instead.
Current rating matters when sizing a shunt: choose one rated comfortably above your maximum expected charge or discharge current, since running near the limit affects both accuracy and longevity. On boats with more than one battery bank, each bank generally needs its own shunt and monitor rather than sharing one, and Bluetooth-equipped models can be viewed together in a companion app once paired.
Synchronisation resets the state of charge reading to full once the bank reaches a genuine full charge, so it is worth checking this has happened correctly after the first few charge cycles rather than assuming the display is accurate from day one.
