Lugs – Types, Applications and Features

Scope of Electrical Lugs

A cable lug also known as a cable terminal is a component of an electrical device that connects the cable to the device terminals. It  simplifies the assembly of personnel, maintenance, and repair processes. A cable lug or connector is used when a permanent connection is required, but a direct one is inconvenient or impossible to achieve.

Lugs are made of high-grade electrolytic copper (ETP Grade) and available in a range of diameters and mounting holes, with wire sizes ranging from #8AWG to 1000MCM. The terminals are CSA & UL approved and have corrosion-resistant tin plating.

Classification of  Various Types of Lugs/Terminals

Copper Terminals

Copper lugs are ideal in large gauge applications for power draw or grounding. The wire can be soldered or crimped to each copper lug. One end of the copper terminal takes the cable by soldering, welding, or crimping, depending on the type of lug used. The other end of the copper lug is secured to a matching termination or connection point by a bolt, screw, or spring clip.

 

Copper Cable Lugs offer easy installation and long-term dependability. AXIS Copper Lugs are made of high-grade ETP Copper material and tinned for corrosion protection. Excellent for any outdoor application or in a marine environment.

With cable sizes ranging from 1.5 sq mm to 1000 sq mm, our Electrical Lugs are dependable with rapid termination methods for interconnecting heavy gauge power cables to bus bars, relays, batteries, solar power inverters, power cables, grounding devices, and more, with increased efficiency, safety, and reduced costs.

 

Aluminium terminals are manufactured from the solid aluminium rod using high conductivity (99.6% pure) aluminium. The lugs are forged from solid material and are suitable for outdoor use (as the palm ends are sealed).  The Aluminium Lugs are supplied with jointing compounds in the barrels and sealed with an end cap. We have a list of standard sizes but can manufacture according to the requirement. Crimping takes place with hex dies and usual aluminium cable preparation.

Copper lugs are better in numerous ways, however; these lugs are a bit more expensive than aluminium lugs. Due to its low price, aluminium wires and lugs are in almost every wiring system. Aluminium lugs related innovations are being made, making them as safe and convenient as copper lugs.

Aluminium lugs are tinned with a middle layer of copper coating for corrosion protection and are barrel entry chamfered at the end to provide easy insertion into a barrel.

The inner barrel of the lug has an AntiOxide compound, which reduces oxide formation caused inside and helps to get a better connection after crimping the lug with the conductor; however, UL listed aluminium lugs come with AL9CU marking, which is rated for a 90o C system.

 

Bimetallic Lugs

Axis bimetallic terminals made of Friction welding establish the highest quality connection between the copper palm and the Aluminum barrel.

Bimetallic Lugs are used in Solar Plants to connect aluminium conductors to copper busbars in a range of electrical applications such as control panels, switchgear, and combiner boxes.

 

The Aluminum barrel is friction welded to the copper palm, achieving the best possible transition between barrel & palm.

As a result, the aluminium conductors touch the aluminium barrels, and the copper busbar touches the copper palm. To prevent oxidation lug barrel is filled with contact lubricant which improves contact properties, enabling smooth electrical connection.

We manufacture a wide range of lugs, connectors and specialised items to meet specific customer needs. Other combinations can be made if needed:

1-Bi-metallic lugs – Aluminium barrel with copper palm (with single, double, or four holes)

2-Bi-metallic lugs with copper washer (Aluminium lug with copper washer)

3-Bi-metallic lugs reverse type (Copper barrel with aluminium palm)

4-Bi-metallic connectors – Straight type (for the same cross-section of Al & Cu cables)

5-Bi-metallic connectors – Reducing type (for different cross-sections of Al & Cu cables)

6-Bi-metallic connectors – Pin type (Aluminium barrel with solid copper pin)

 

 

Crimping Lugs

Crimping is the process of deforming one or both of two pieces of metal or similar material to hold the other in place. The bend or deformity is called a crimp.

Crimping lugs are connectors that connect cables, surfaces, and machinery. The clamps connecting wires to an automotive battery, and the ends of battery jumper cables, are examples of crimping lugs.

They are used in automobile wire systems, electrical boxes, machinery, household appliances, electronics, and other durable goods. For electrical applications, insulate them with rubber or plastic. They prevent accidental energy transfers to people or neighbouring electrical components.

 

Mechanical Lugs

Mechanical connector technology, which is the best-fit method for attaching cable conductors, use cutting-edge technology such as shear-off bolted connectors. Here the bolt head is sheared off at a predetermined torque. These mechanical connectors or shear bolt connectors are of certain alloys.

These connectors are of sleeves and lug bodies, which are of a high-tensile aluminium alloy. The interior surfaces of the connectors are grooved, and the sleeves are suitable for underground use. Lugs are available in several palm hole sizes and are appropriate both outside and inside. These products are also available in low-voltage, medium-voltage, and high-voltage versions.

Compression Lugs VS Mechanical Lugs

Compression lugs are for small electrical works and mechanicals for large (buildings or large commercial cables). The Compression lugs are much smaller than mechanical lugs.  Mechanical lugs connect large wires, such as cable wires. Because of their build and design, they are used in autos. Compression lugs are commonly seen in residences and small business structures when wire connectors are required. 

 

Features & Characteristics of Various Types of Cable Terminals

a) There is a mechanical pull-out test & electrical durability test for entering the wire barrel. The shockproof portions of the entry are bell-mouthed, allowing smooth insertion of the conductors.

b) The cable lugs go through high current tests at temperatures of 250°C. Great-quality materials provide optimal conductivity, high loading capacity, and increased safety.

c) Flat contact surfaces and an inside chamfer make for a simple and secure connection. Copper lugs are annealed to a specific temperature to improve material properties and better crimping.

d) All copper items are electro-tinned to BS specifications, which prevents corrosion and oxidation, terminals insulated with PVC give outstanding dielectric strength and support.

e) Copper tube dimensions are customised to fit a specific Sq.mm of cable, ensuring complete electrical conductivity and mechanical strength to withstand vibration and pull-off.

 

Application of  Different Types of Electrical Lugs

Cable lugs make installation, repair and maintenance of electrical devices and cables simple. They link two wires together or connect more than two cables. They also connect fuse sockets, load switches, and electrical equipment. Insulated lugs with pin terminals, blade terminals, hook terminals, fork terminals, and ring terminals are in the wire, automation, control panel, and instrumentation industries. Copper ring-type lugs are for many connecting reasons. Copper cable lugs connect several of the gadgets with cables.

Butt and parallel connectors are other forms of the lug that join and terminate two cables. PVC insulated, butt type, heat shrinkable, and closed-end type are among the most commonly used butt and parallel connections. It comes in a variety of sizes, shapes, and materials. Depending on the type of cable used to connect one item to another, copper cable lugs are used as butt and parallel connectors. In the wire and electrical sector, lugs have indispensable usage. Before applying them in a heavy-duty machine, they get tested for strength. The strength and design of lugs are crucial in many applications. Ensure to choose the correct lugs based on their intended use.

They are often used to connect distribution boxes and transformers to cables. Terminations in LV/MV connections terminate all cable and electrical switching in environments where vibration is a factor. Transformers, motors, generators, batteries, distribution boards, and other industrial segments use it. Especially in control panel cubicles to terminate flexible control wires to metres, connectors, and terminal blocks.

 

 

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