Common types of electrical accessories mainly include four categories: connecting devices, protective devices, control components, and mounting accessories. They are widely used in power systems and electrical equipment.
Connecting Devices
Used to achieve reliable circuit connections and signal transmission:
Terminal terminals: Including screw-type, spring-loaded, and pluggable types, used for wire connections to ensure stable electrical contact.
Plugs and sockets: Such as power plugs and industrial connectors, enabling quick connection of equipment to power or signal sources.
Gathering boxes: Used for centralized connection and protection of multiple wires, commonly found in building wiring systems.
Protective Devices
Ensuring circuit safety and preventing damage from overloads, short circuits, or lightning strikes:
Circuit breakers: Automatically disconnect the circuit in case of current overload or short circuit, such as air switches and molded case circuit breakers.
Residual current devices (RCDs): Quickly trip when a leakage current reaches 30mA to prevent electric shock accidents.
Surge Protector (SPD): Suppresses instantaneous high voltage caused by lightning or power grid fluctuations, protecting precision electrical appliances.
Fuse: Interrupts fault current by melting the fusible element; commonly used in high-voltage or low-voltage power distribution systems.
Control Components: Implementing automatic or manual control functions in circuits:
Relay: Uses a small current to control the switching of a large current; includes intermediate relays, thermal relays, solid-state relays, etc.
Contactor: Primarily used for frequently connecting and disconnecting high-power loads, such as AC contactors in motor control circuits.
Switch: Such as push-button switches, limit switches, dual-power transfer switches, etc., used for inputting operation commands.