FC stands for Fixed Connection. It is fixed by way of a threaded barrel housing. FC connectors are typical in test environments and for singlemode applications. FC connectors were designed for use in high-vibration environments. The FC Connector is the most popular connector used today. It can be seen in every area of the communications environment, from a telecom's distribution room to a LAN closet, the FC has set the standard for optical Fiber connectors. FCS are being replaced by SC and LC connectors.
FC connectors offer extremely precise positioning of the fiber optic Cable with respect to the transmitter’s optical SourceEmitter and the receiver’s optical detector. They feature a position locatable notch and a threaded receptacle.
FC connectors are generally constructed with a metal housing and are nickel-plated. They have ceramic ferrules and are rated for 500 mating cycles. The Insertion Loss for matched FC connectors is 0.25 dB.
FC is the Fiber Optic Connector standard for Nippon Telephone & Telegraph (NTT) installations, developed with Nippon Electric Co. (NEC).
TIP: The FC screws on firmly, but make sure you have the Key aligned in the slot properly before tightening.