How to use cable glands

When carrying out operations in harsh or hazardous environments, the use of the correct industrial components is of the utmost importance. Selecting the wrong products that are not designed to withstand such conditions can lead to serious issues and ultimately hold up the application as a whole.

Cable glands are critical elements that are essential for maintaining the reliability of the equipment being used, which means that cables, cords and wires need to be carefully protected from the risk of damage to ensure operations continue to run smoothly, regardless of the industry you are in.

Here, we explain how to use cable glands in detail, providing the information you are likely to need when determining the best products to use for your application.

How do cable glands work?

Cable glands are components that are widely used when terminating cables in harsh or hazardous settings. They are used to seal the ends of cables and secure them to plugs, terminals, enclosures or electrical equipment of various kinds. They can protect sensitive electrical wiring from moisture, contamination or corrosion.

Cable glands are manufactured by combining a central enclosure or body through which cabling can pass with several attachments. Typically, these attachments are:

• Lock nuts
• Washers
• Seals
• Attachment claw/cones
• Sealing nut

Some types of cable glands also feature two-part enclosures, tags for electrical earthing, PVC shrouding or rubber sealing.

What are cable glands used for?

Cable glands have the following principal functions:

• Fixing cables in place and preventing them from being twisted or accidentally pulled out
• Providing an airtight seal to protect from dust, dirt, water and moisture
• Fortifying cables against strain
• Protecting the vulnerable end of the cable from damage
• Reducing the risk of shocks and electrocution

If utilised in potentially explosive settings, it is essential that cable glands are approved for the environment in which they sit. They must also keep the level of protection of the equipment to which they are connected.

These components are often utilised by the following industries:

• Broadcasting
• Energy
• Food & Beverage
• Instrumentation
• Lighting technology
• Surveillance
• Transportation
• Water technology

One of the main benefits of using cable glands is that they have an IP68 waterproof function, which means they can be utilised to make watertight exit points from severe and adverse environment enclosures and through bulkheads.

What are the components of a cable gland?

The parts of cable glands are determined according to cable gland types, which are:

Single compression cable gland

A single compression cable gland has scope for corrosive and moisture vapour to enter and impact the cable, and does not feature a cone and cone ring. Single compression cable glands consist of the following components:

• Gland body nut
• Gland body
• Flat washer
• Check nut
• Rubber washer
• Rubber seal
• Neoprene (rubber)

Double compression cable gland

A double compression cable gland is employed where largely armoured wires are leaving or entering the board. They provide additional support, with a double sealing feature, as well as a cone ring and cone. Double compression cable glands have the following components:

• Check nut
• Neoprene rubber seal
• Cone ring
• Cone
• Gland body nut
• Gland body

What materials are cable glands made from?

The most common materials used in the production of cable glands are:

• Steel
• PVC
• Polytetrafluoroethylene (PFTE)
• Polyamide/nylon
• Brass
• Aluminium

What are the key considerations when choosing cable glands?

When selecting a cable gland for a particular application, there are a number of considerations to keep in mind. These include:

• Temperature range - the complete range of ambient operating temperature
• Pressure rating - the pressure the cable gland can endure without leakage
• Number of wires - the number of elements the assembly could accommodate
• Opening diameter - the selection of sizes the cable gland can accommodate
• Mounting size - the size of the mounting or thread feature

How are cable glands installed?

Cable gland installation should be carried out following the appropriate codes of practice and local regulations by a competent and experienced professional.

Care must be taken to prevent damage to the entry threads when organising and installing cable glands. It is of the utmost importance that cable glands are not installed when the circuits are live, and they should not be opened until the circuit has been de-energised.

When utilising cable glands, components should not be used in conjunction with those from other brands. Doing so will impact the safety of cable gland installation and cancel any explosion protection certification.

Care should also be taken to prevent exposure of cable gland sealers to hostile chemical substances and dirt.

Find out more

If you want to know more about Cable Glands or need guidance with selecting a suitable solution for your application, Northern Connectors is here to help.

You can explore the Glands & Cable Protection section of our website, call us on 01744 815001, or complete our online contact form and we will be in touch at the nearest opportunity.