The above Battery charger is protected against :

• Over Charging
  
• Short Circuit
  
• Reverse Polarity
  
• Under / Over voltage

The Constant voltage Charge Method is recommended to charge Maintenance free Batteries. As charging proceeds, the lead surface of the Positive Plate becomes Lead peroxide. When charging continues further, the Positive Plate begins generating O2 to cause a sudden rise in Battery Voltage, A Constant Voltage Charge therefore gives rise to detection of this voltage increase and control of the charge amount. This type of charging generally employs a constant-voltage constant current method with current limitation to prevent the initial current (at low battery voltage ) from increasing.