Introduction:
Unarmoured cable glands play a vital role in the safe and efficient installation of electrical cables. They provide a secure connection between the cable and equipment, ensuring protection against environmental factors, such as dust, moisture, and mechanical stress. In this comprehensive guide, we will explore the characteristics, applications, installation, and benefits of unarmoured cable glands.
What is Unarmoured Cable Gland?
An unarmoured cable gland is a specialized mechanical fitting designed to secure and seal unarmoured electrical cables where they enter electrical equipment, enclosures, or junction boxes. It acts as a barrier, preventing the ingress of moisture, dust, and other contaminants into the electrical system. Additionally, it offers strain relief, preventing undue stress on the cable termination points.
Components of an Unarmoured Cable Gland
Typically, an unarmoured cable gland consists of several components:
- Gland Body: The main part of the cable gland that houses the cable and provides mechanical support.
- Locknut: Used to secure the cable gland to the equipment or enclosure.
- Sealing Ring: Ensures a tight seal between the cable gland and the cable entry point.
- Earth Tag: Optional component used for earthing purposes.
- Shroud: A protective cover that provides additional sealing and strain relief.
Types of Unarmoured Cable Glands
There are several types of unarmoured cable glands available, each suited for specific applications. The three main types are:
1. Threaded Cable Glands:
Threaded cable glands are widely used and feature an internal or external thread that enables them to be screwed onto the equipment or enclosure. They provide a secure and reliable connection and are available in various materials.
2. Compression Cable Glands:
Compression cable glands use a compression seal to secure the cable. They employ a compression nut that compresses a seal onto the cable, creating a watertight connection. These glands are commonly used in hazardous environments.
3. Flange Cable Glands:
Flange cable glands are designed to be mounted on a flat surface, such as a control panel or junction box. They feature a flange and sealing gasket, which ensures a tight and secure connection.
Unarmoured Cable Gland Materials
Unarmoured cable glands are available in different materials, including:
1. Brass Cable Glands:
Brass cable glands are widely used due to their excellent conductivity, corrosion resistance, and durability. They are suitable for various applications and can withstand harsh environments.
2. Stainless Steel Cable Glands:
Stainless steel cable glands offer superior corrosion resistance and are ideal for applications where exposure to moisture, chemicals, or extreme temperatures is a concern. They are commonly used in marine or industrial environments.
3. Plastic Cable Glands:
Plastic cable glands are lightweight, cost-effective, and resistant to certain chemicals. They find applications in less demanding environments where corrosion resistance is not a primary concern.
Key Features and Benefits of Unarmoured Cable Glands
Unarmoured cable glands offer several important features and benefits, including:
- Protection against dust, moisture, and contaminants.
- Strain relief, preventing damage to cable terminations.
- Secure and reliable connection.
- Easy installation and maintenance.
- Compatibility with various cable types and sizes.
- Resistance to corrosion, chemicals, and UV radiation.
Applications of Unarmoured Cable Glands
Unarmoured cable glands find extensive use in various industries and settings, such as:
1. Industrial Sector:
Unarmoured cable glands are widely employed in industrial applications, including manufacturing plants, oil refineries, and chemical processing facilities. They protect cables from harsh conditions and ensure uninterrupted power supply.
2. Construction Sites:
Construction sites often require temporary power supply connections. Unarmoured cable glands enable safe and reliable cable installations, protecting against weather conditions and potential damage.
3. Commercial Buildings:
In commercial buildings, cable glands secure the cables entering electrical panels, distribution boards, and control systems. They contribute to the overall safety and longevity of the electrical infrastructure.
4. Power Distribution Networks:
Unarmoured cable glands play a crucial role in power distribution networks, ensuring secure connections at substations, transformers, and switchgear installations.
Installation of Unarmoured Cable Glands
Proper installation is essential for the effectiveness and longevity of unarmoured cable glands. The installation process typically involves the following steps:
1. Cable Preparation:
Prepare the cable by removing the outer sheath and any fillers or armor. Ensure the cable’s conductors are clean and free from damage.
2. Cable Gland Assembly:
Assemble the cable gland components, including the gland body, sealing ring, and locknut. Follow the manufacturer’s instructions to ensure a proper fit.
3. Securing the Cable Gland:
Carefully insert the cable through the gland body. Tighten the locknut to secure the cable gland onto the equipment or enclosure. Ensure a tight and secure fit without damaging the cable.
4. Testing and Verification:
Perform visual and physical inspections to verify the correct installation of the cable gland. Check for proper sealing, strain relief, and secure connections.
Choosing the Right Unarmoured Cable Gland
When selecting an unarmoured cable gland, consider factors such as the cable type, size, operating conditions, and required IP (Ingress Protection) rating. It is crucial to choose a gland that matches the specific requirements of the installation to ensure optimal performance and protection.
Maintenance and Inspection
Regular maintenance and inspection are necessary to ensure the ongoing effectiveness of unarmoured cable glands. Inspect the glands periodically for signs of damage, wear, or improper sealing. Replace any damaged or worn components promptly to maintain the integrity of the electrical system.
End-note
Unarmoured cable glands are essential components in electrical installations, providing protection, sealing, and strain relief for unarmoured cables. By understanding their types, materials, installation procedures, and applications, you can make informed decisions when selecting and installing cable glands. Remember to prioritize safety and consult with professionals when necessary to ensure a reliable and efficient electrical system.
FAQ
No, unarmored cable glands are not suitable for use with armored cables. Armored cables require specific cable glands designed to provide proper sealing and strain relief for the armor layer.
No, unarmoured cable glands are not suitable for outdoor installations. They lack the necessary protection against environmental factors such as moisture, dust, and physical damage. Armoured cable glands are designed for outdoor use to ensure proper insulation and durability.
To determine the correct gland size for your cable, measure the cable’s outer diameter and refer to the manufacturer’s gland sizing chart. Choose a gland size that accommodates the cable diameter within its recommended range.
Non-armored cable, also known as unarmored cable, is a type of electrical cable that does not have any protective metallic armor or sheathing. It is commonly used for indoor installations where additional protection is not required.
