What are the types of cable glands and how to use them?

The purpose of cable glands

Cable glands perform a number of essential roles in cable management. Designed to attach and secure the end of an electric cable and the device it’s connected to, cable glands provide earthing, grounding, insulation, bonding and strain relief. They can also be used to seal cables which pass through bulkheads of gland plates.

They are often located in hazardous or harsh environments where they need to contain electrical sparks of flames, or repel outside contaminants such as dust, dirt and fluids. In addition to this, their job is to stop cables becoming twisted or pulled to ensure a secure connection and continual performance.

How to choose cable glands

There’s a world of choices out there and unfortunately no one-size-fits-all option. But it does mean that you can custom select a cable gland based on your parameters. And to do that, you first need to consider a range of environmental and application factors.

The role of the environment

It doesn’t matter whether you’re working in aerospace, industrial, marine, power and utility, telecommunications or any other key industry. What’s important is identifying the core application environment of your cable gland. Questions to ask yourself:

Are you using it indoors or outdoors?

Will it be situated in a safe industrial zone or a hazardous or explosive environment?

What’s the temperature and is it constant?

Is the surrounding area damp or dusty?

Are there any gases or corrosive materials nearby?

Your answers will help determine the cable gland specs and whether it requires a special protective plating or coating.

Metal cable glands are used in a range of applications, including the chemical industry, technology and areas with high demands on special mechanical and chemical stability. The pros are durability over time, even in wet conditions, and its rigid stability.

Plastic cable glands have a wide cable range due to their claw and seal design, which makes them extremely adaptable to a wide range of applications. The pros are resistance to salt water, grease and weak acids, to name a few.

How to install a cable gland

Cable gland installation depends on the type of gland you’re using, but the basics are the same. You’ll need to follow the relevant codes of practice, your local regulations and the manufacturer’s cable-gland-installation instructions. Installation should only be carried out by a skilled person with experience and knowledge of cable glands.

Note: Take care not to damage loose entry wires.

Getting started

Step 1: Turn off all electrical equipment and disconnect any live wires

Step 2: Make sure your cable gland is compatible with your cables

Step 3: Keep cable glands clear of solvents, chemical substances, and dirt during installation

Installing cable glands

Step 1: Open the cable gland and remove the nut.

Step 2: Peel back the outer sheath of the cable to the same length of the cable gland itself. If there’s an inner metal armour, expose it.

Step 3: Insert the right end of the gland into the cable.

Step 4: Lay the peeled sheath or armour evenly around the gland.

Step 5: Apply the nut, taking care to tighten with a spanner to secure the gland in place.