I am planning on using a Victron Blue Smart 12/20 charger for LiFePO batteries. Reading the manual it worries me as the procedure for stopping charging is described to be done in a definite order with AC switched off before removing connection to battery. Now, if the Lithium battery BMS goes into over voltage protection it will switch a relay removing the connection to the battery. Will this damage the charger? Should there be a separate AC relay controlled by the BMS to remove the AC feed to the charger before cutting the DC path to battery?