Victron Energy Smart BatteryProtect 12/24V 65A

Protects the battery against excessive discharge and can be used as a system on/off switchThe Smart BatteryProtect disconnects the battery from non-essential loads before it is completely discharged (which would damage the battery) or before it has insufficient power left to crank the engine. The on/off input can be used as a system on/off switch.
12/24 V auto rangingThe Smart BatteryProtect automatically detects system voltage one time only.
Bluetooth: programming made easyWhen using Bluetooth to program the Smart BatteryProtect any required engage/disengage levels can be set. Alternatively, one of nine predefined engage/disengage levels can be set with the programming pin (see manual). If required, Bluetooth can be disabled.
A special setting for Li-ion batteriesIn this mode the BatteryProtect can be controlled by the VE.Bus BMS.Note: the BatteryProtect can also be used as a charge interrupter in between a battery charger and a Li-ion battery. See connection diagram in the manual.
Ultra-low current consumptionThis is important in case of Li-ion batteries, especially after low voltage shutdown. 
Over voltage protectionTo prevent damage to sensitive loads due to over voltage, the load is disconnected whenever the DC voltage exceeds 16.3 V respectively 32.6 V.
Ignition proofNo relays but MOSFET switches, and therefore no sparks.
Delayed alarm outputThe alarm output is activated if the battery voltage drops below the preset disc
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