Let’s understand Parallel Groove connectors, commonly known as PG Clamp. If you’re involved in electrical systems or just curious about the essential components that keep our power grids running smoothly, this blog is for you. We will explore what a PG Clamp is, the different types of PG Clamp available in the market, and the various applications of PG Clamp in the field.

But why trust us? At Axis, we’ve been at the forefront of manufacturing a wide range of Clamps and Connectors for the past 30 years. Our products are integral to overhead lines and utility-scale applications worldwide. With our extensive experience and dedication to quality, we’re here to share valuable insights that will enhance your understanding of PG Clamp and its significance in electrical systems.

What exactly is a PG clamp?

PG clamps are used to connect two or more conductors whose axes are parallel to each other.

PG Clamps are designed and installed to ensure that conductors don’t come in direct contact with each other. When conductors are connected directly without a proper connecting mechanism, there will be increased electrical resistance at the contact points, resulting in heat build-up and energy loss. Hence, to avoid such harmful electrical discharge in earthing applications, transmission and distribution lines, a PG Clamp is crucial.

How the clamp is installed?

A PG Clamp is made by joining two parts. These gaps are called grooves, where you insert the conductors. The grooves are parallel to each other, which is why it’s called a Parallel Groove Clamp.

Now, let me show you how to use this clamp. In this case, you can see a code showing A 16-120 where “A” stands for Axis, and “16-120” means a conductor within a range of 16 to 120 mm square can fit inside.

Here you can insert a 16 mm square and 120 mm square conductor.

Types of PG Clamps

PG Clamps are made from materials like aluminium, brass, or galvanized steel. They face high electrical and mechanical stresses based on their application. So, let’s talk about their types with respect to their applications.

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Aluminium PG Clamp

This PG Clamp is majorly used on aluminium conductors for power distribution and transmission, ranging from low to high voltage up to 220 kV applications, depending upon designs and specifications. They are designed to connect two conductors in parallel to accept a tap connection.

There are different types available like single, double, and three-bolt clamps. The types vary depending on the size and current-carrying capacity of the conductor.

An Aluminium PG Clamp is used when both conductors are made of aluminium. If one of them is copper, then you need a Bimetallic PG Clamp. Because when two different metals are in contact for a long time, they cause dissimilar metal corrosion.

Bimetallic Clamps

Bimetallic clamps solve this problem by preventing direct contact between aluminium and copper. This happens due to friction welding and forging inside one of the grooves.  Thus, dissimilar metal corrosion is avoided. Bimetallic clamps also come in different sizes and bolts types, just like Aluminium Clamps.

Brass PG Clamps

These clamps are made from brass or bronze and are primarily used for earthing and lightning protection applications. They are designed to securely hold copper conductors on both sides, ensuring a stable connection.

How to check the quality of PG Clamps?

1) Thickness: Thickness determines the current carrying capacity. If the clamp is too thin for the application, it won’t handle the mechanical stress and electrical load properly. This can lead to overheating, deformation, or even failure under load.

2) Corrosion: Corrosion can lead to increased electrical resistance, causing heat build-up and potential failure. It also weakens the mechanical strength of the clamp, leading to breaks or cracks.

One technique adapted to avoid corrosion is Tin Plating. Also known as tinning, it is an industrial process where the surface of metal objects is coated with a thin layer of tin. This plating helps resist corrosion and ensures good electrical conductivity. It creates a protective layer that prevents oxidation and improves the clamp’s durability and performance.

I hope you now have a brief understanding of PG Clamps and their role in Electrical Safety. At Axis, our team of over 50 engineers is ready to support your project needs for Clamps, Lugs & Connectors, and hundreds of other electrical hardware.

Why Axis Electricals?

At Axis, we have a team of over 50 engineers ready to assist you with designing, installing, and testing your Lightning Protection Systems. Our arresters are trusted and installed in a variety of settings around the world, including substations, data centers, factories, and even everyday residential and commercial buildings.