What are cable conduits? Types of conduits and applications

Cable conduit, also known as electrical conduit, is a type of plastic or metal tubing used to contain and protect electrical wires or cables. It is available in rigid or flexible forms and can be used in a wide range of installation conditions, from indoor spaces to outdoor environments.

To meet diverse installation requirements and system configurations - including concrete-embedded installations and underground applications - electrical conduit is manufactured in various types and sizes.

Electrical conduit must be properly terminated at an electrical box or an equivalent enclosure. Together with electrical boxes and conduit accessories such as connectors and fittings, conduit forms a critical part of the electrical raceway system. When made of metal, the conduit itself can also function as a grounding conductor for the electrical system.

Electrical conduits are used for a wide range of purposes, including:

• Compliance with technical standards: Electrical conduits are often mandatory under regulations such as the U.S. National Electrical Code (NEC) or requirements set by local authorities. In Vietnam, the applicable standard is TCVN 7417-25:2015, which is fully equivalent to IEC 61386-25:2011.
• Protection of electrical wires and cables: These accessories help protect wires and cables from various hazards such as fire, moisture, mechanical impact, chemicals, as well as risks from rodents and insects. Although electrical cables already have their own insulation, conduit systems provide a significantly higher level of protection.
• Meeting design and installation requirements: By acting as an additional protective layer, cable conduits expand installation possibilities. For example, high-strength conduits allow cables to be installed in exposed locations where using standalone wires or cables would not be safe.
• Reduction of EMI: Conduit systems, especially metal conduits can help reduce EMI, improving the performance and stability of electrical wiring and cable systems.
• Improved organization and ease of installation: In complex electrical systems with multiple cables, conduits help keep wiring neat, organized, and easier to manage. The smooth interior surface of conduits allows cables to be pulled and repositioned easily, simplifying installation as well as future maintenance or replacement.

For many electrical systems, cable conduit provides a comprehensive protection solution while offering a high degree of flexibility in both design and installation.

In practice, corrugated electrical conduit systems are widely installed in residential, commercial, industrial, and infrastructure projects. They help ensure compliance with safety regulations, reduce fire risks, and extend the service life of electrical systems.

• Commercial buildings (offices, shopping malls, hospitals): Conduits protect complex electrical networks used for lighting, equipment, and security systems. Their use ensures operational safety, compliance with building codes, and easier maintenance - especially in high-reliability environments such as hospitals.
• Industrial automation and manufacturing: In factories and production lines, heavy-duty and chemical-resistant conduits are used to protect wiring for machinery, industrial robots, and control panels. This solution minimizes vibration and mechanical impact, reduces electrical failures, and enhances equipment durability.
• Infrastructure and construction: Projects such as airports, metro systems, and water treatment plants rely on conduits for underground power and control signal wiring, protecting them from environmental impacts while meeting strict safety standards.
• Residential buildings and smart homes: In housing projects, electrical conduits support concealed wall installations and allow easy upgrades for smart home systems, IoT devices, lighting, and security cameras - offering long-term flexibility and safety.
• Renewable energy applications: In solar and wind power systems, conduits protect outdoor cables, improving durability and ensuring stable, reliable operation over time.

Electrical conduits are available in a wide range of types, designed to meet different installation conditions and application requirements. The market offers various sizes and materials, generally classified into two main categories: flexible conduit and rigid conduit.

4.1 Characteristics of flexible cable conduit

Flexible conduit is designed with high bendability, making it ideal for confined spaces or installations subject to vibration or movement during operation. This type of conduit is commonly used in environments with machinery, industrial robots, or systems that experience motion while operating.

Because it does not require specialized tools for bending or shaping, flexible conduit simplifies installation and significantly reduces labor time and costs.

Today, flexible conduits are available in several versions, including metallic flexible conduit and non-metallic flexible conduit. Plastic (non-metallic) conduits offer advantages such as lightweight construction, corrosion resistance, and easy cutting. They are particularly effective in high-humidity or chemically aggressive environments where metal materials are more prone to degradation.

4.2 Characteristics of rigid cable conduit

Rigid conduit is manufactured from high-strength materials such as galvanized steel, stainless steel, or aluminum. This type of conduit provides superior mechanical protection, making it suitable for systems that require long-term stability and robustness.

As rigid conduit is not easily bent, it is typically installed in straight runs, with directional changes made using elbows or specialized bending tools.

Rigid conduit is widely used in industrial plants, commercial buildings, and outdoor installations. According to technical standards and electrical codes, it is often mandatory in locations where electrical wiring must be protected from impact, mechanical stress, or harsh environmental conditions. In certain applications, rigid metal conduit can also serve as a grounding conductor, further enhancing overall electrical system safety.

5.7 Cable conduits for F&B industry

The F&B industry is subject to strict sanitation and hygiene requirements to prevent contamination during production. If not properly designed and maintained, electrical conduits and their associated fittings can become breeding grounds for bacteria and contaminants, which may reach the processing line or compromise the sterile manufacturing environment.

The U.S. Food and Drug Administration (FDA) issues guidelines and requires third-party testing to help manufacturing facilities mitigate contamination risks. As a result, electrical conduits used in food-processing plants must be made from sanitary, easy-to-clean materials and, in certain areas, be safe for indirect food contact. These standards are defined and enforced by organizations such as the NEC (National Electrical Code), OSHA (Occupational Safety and Health Administration), UL, and ECOLAB.

HELUKABEL's Anaconda Sealtite® NMFG-Clean PVC flexible conduit is particularly suitable for the F&B, pharmaceutical, biotechnology, chemical, and other industries. Key features of this product include:

• IP67-rated protection against water and dust
• Made from special PVC material compliant with FDA CFR 21 and NSF 51 standards
• Resistant to chemical cleaning and disinfecting agents
• Inhibits the growth of harmful microorganisms