RV ship 275A 48Vdc battery main switch, central control main switch ON off

In the case of AFD (AC generator field disconnection), AFD will cut off the emergency circuit breaker before the battery switch is turned off, thereby protecting the AC generator. Simply put, it is to protect the AC generator. When the AC generator is started, the battery switch cannot be turned off. Otherwise, the power of the generator will have no output voltage, and the generator will burn out its diodes. So the correct method is to turn off the engine generator and then turn off the battery switch. The AFD function of this battery switch connects two spiral feet to the magnetic field end of the AC generator, which can avoid accidental operation by the staff. And it caused the secondary tube of the AC generator to burn out.