Thomas Betts 54178 Square Ring Terminal 5/16 Stud Copper

Product Description

The THOMAS BETTS 54178 is a non-insulated square ring terminal designed for compression-style electrical connections in professional wiring applications. It features a copper contact body with a titanium nitride (TiN) plating for corrosion resistance and reliable conductivity. The terminal measures 2.33 inches in overall length and 1.25 inches in ring width, with a 5/16-inch stud hole size. Electricians and panel technicians use this terminal to create permanent, low-resistance lug connections on wire ends before securing them to buss bars, ground lugs, or equipment terminals. Its non-insulated design is appropriate where sleeving or heat shrink will be applied separately or where code does not require insulated terminations.

This square ring terminal is used in commercial and residential electrical work wherever a compression-crimped, non-insulated ring lug is required. Typical applications include control panel wiring, grounding conductors, switchgear assembly, and equipment termination. The square ring profile seats flush against standard hardware fasteners and prevents rotation during tightening. Electricians and industrial maintenance techs are the primary installers. Sold individually, it is suited for single-unit replacement or low-volume panel work.

Key Features

• Non-insulated square ring design seats flat against buss hardware and resists rotation under torque
• Copper contact body provides high conductivity for power and grounding circuits
• Titanium nitride (TiN) contact plating enhances corrosion resistance and long-term connection integrity
• Compression connection type requires a proper ratchet or hex crimp tool for a gas-tight termination
• 5/16-inch stud size fits standard electrical fastener hardware
• RoHS compliant construction for use in environmentally regulated installations

Compatibility

Designed as an OEM-style compression ring terminal for use in standard electrical panel, switchgear, and grounding applications requiring a non-insulated square ring lug with a 5/16-inch stud size.

Installation Notes

Installation should be performed by a qualified electrician in accordance with NEC requirements for terminal connections. De-energize the circuit and verify absence of voltage before terminating any conductor. Use a calibrated ratchet crimp tool rated for the wire gauge and terminal type to ensure a proper compression connection. Do not use pliers or uncalibrated tools, as an improper crimp can result in a high-resistance joint or conductor pullout.