Construction and Contact Design
The plug housing is typically manufactured from clear polycarbonate rated UL 94V-2 for durability and visual inspection of wire placement. Contacts are made of phosphor bronze and plated with gold—commonly 15 or 50 micro-inches—to ensure reliable signal transmission and corrosion resistance. Termination is achieved through insulation displacement contacts (IDC) that pierce the conductor insulation when crimped.
Contact prong design varies by conductor type.
Ttri-point contacts accommodate both solid and stranded conductors, while piercing-type contacts are suitable only for stranded cable. For solid conductors, three-prong designs are preferred as they wrap around the wire rather than penetrating it, reducing the risk of conductor fracture.
Performance Categories and Compatibility
RJ45 STP plugs are available in performance grades aligned with cabling categories. Cat5e plugs support frequencies up to 100 MHz for Gigabit Ethernet applications. Cat6 plugs are rated to 250 MHz, enabling 10GBASE-T transmission over limited distances. Cat6A variants support 500 MHz for full 10 Gigabit Ethernet channels. The plug must match or exceed the category of the cable being terminated; system performance is limited by the lowest-rated component.
Cable Compatibility
These plugs accommodate round FTP/SFTP cable with conductor sizes typically ranging from 24 to 26 AWG and outer jacket diameters up to approximately 6.2 mm. They are compatible with solid or stranded conductors, though the appropriate contact design should be selected for the intended cable type. Solid cable is preferred for permanent horizontal runs, while stranded cable is used for patch cords requiring flexibility.
Standards and Applications
RJ45 STP modular plugs are specified under ANSI/TIA-568 and ISO/IEC 11801 generic cabling standards, which define performance requirements for balanced twisted-pair components and channels. These plugs support voice, data, and video services, and are suitable for PoE (Power over Ethernet) applications where both power and data are delivered over a single cable.