The charging port is the part of the charger which you slide your battery pack onto or into to charge it. Most chargers have just one port while others have multiple ports.
Contacts
The contacts are made from a conductive metal which touches the battery contacts when the battery is in the charging port. This completes the electrical circuit and allows the battery to be recharged.
Power lead
The power lead plugs into the mains electricity and provides the energy needed to recharge the battery using the charger. The lead is permanently attached to the charger on most models.
Diagnostic LEDs
The diagnostic LEDs show different charging statuses and conditions. The simplest will just indicate when the battery pack is charging, charged or there is an error. Others include information on the temperature of the battery and charger and if there is a problem with the power source or battery.
Cooling system
Many chargers include a cooling fan system to prevent overheating of the battery or charger because the charging process produces a lot of heat.
Casing
The casing is made from plastic, an electrical insulator. It keeps the electronic parts together and also provides a stable base on which to charge a battery pack so it doesn’t fall over even if the battery is heavy. Some casings are designed to be hooked onto a wall.
Printed information
Sometimes charger information is printed on the side of the casing but most of it is on the base of the charger, either printed directly onto the casing or on a sticker. The most important information is under primary (Prim.) and secondary (Sec.). Primary is a description of the electrical input the charger requires (usually UK household mains power). Secondary is a description of the electrical output into the battery.
