4.3 DC load: disconnecting the load with a BatteryProtect
A Battery Protect will disconnect the load when:
-
input voltage (= battery voltage) has decreased below a preset
value, or when
-
the remote on/off terminal is pulled low.
The Smart BMS CL 12-100 can be used to control the remote on/off terminal
of a BatteryProtect.
Contrary to a Cyrix or contactor, a BatteryProtect can start a load with a large
input capacitor such as an inverter or a DC-DC converter.
4.4 Charging the LiFePO₄ battery with an additional battery charger
Battery charging must be reduced or stopped in case of imminent cell over
voltage or over temperature.
The Charge Disconnect output of the Smart BMS CL 12-100 can be used for
this purpose.
The Charge Disconnect is normally high (equal to battery voltage) and
switches to open circuit state in case of imminent cell over voltage.
Battery chargers with a remote on-off terminal that activates the charger when
the terminal is pulled high (to battery plus) and deactivates when the terminal
is left free floating can be controlled directly with the Charge Disconnect
output.
See appendix for a list of Victron products with this behavior.
Battery chargers with a remote terminal that activates the charger when the
terminal is pulled low (to battery minus) and deactivates when the terminal is
left free floating, the Inverting remote on-off cable can be used. See
appendix.
Alternatively, a Cyrix-Li-Charge can be used:
The Cyrix-Li-Charge is a unidirectional combiner that inserts in between a
battery charger and the LiFePO₄ battery. It will engage only when charge
voltage from a battery charger is present on its charge-side terminal. A control
terminal connects to the Charge Disconnect of the Current limiting 12V Smart
BMS.
4.5 Battery
In case of several batteries in parallel and/or series configuration, the two M8
circular connector cord sets of each battery should be connected in series
(daisy chained). Connect the two remaining cords to the BMS.
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