Understanding the Use of Armored Cable in Conduit: A Comprehensive Guide for Electrical Installations

Introduction to Armored Cable and Conduits

Electrical installations require careful consideration, particularly when it comes to the selection of the appropriate cable and conduit systems. One common question that arises is whether armored cable should be placed within a conduit. This article aims to provide a comprehensive guide to help electrical professionals make informed decisions.

Key Factors to Consider

The decision to use armored cable in a conduit depends on various factors, including local electrical codes, the installation environment, and the specific application.

Local Electrical Codes

Always check the National Electrical Code (NEC) or your local electrical code as they may have specific requirements regarding the use of armored cable like AC or MC cable in conduit. These codes ensure that the installation meets safety and compliance standards.

Protection Against Physical Damage

Armored cable is designed to provide some level of protection against physical damage. If the installation is in an area where the cable could be subject to impact or abrasion, additional conduit may be recommended to enhance protection.

Moisture and Corrosion

If the installation is in a damp or corrosive environment, using conduit can provide extra protection for the armored cable. Conduit can shield the cable from moisture and corrosive elements, ensuring long-term reliability and safety.

Type of Armored Cable

Not all types of armored cable are created equal. Different types of armored cable have different ratings and protections. For example, some cables are rated for direct burial and may not need additional conduit. Understanding the specific requirements of the armored cable is crucial for an effective installation.

Aesthetics and Organization

In some cases, using conduit can help with the organization of wires and improve the appearance of the installation. Proper organization not only improves aesthetics but also makes future maintenance and testing easier.

Practical Steps and Tips

stripping the armor

While armored cable can often be used without conduit, there are situations where using conduit is beneficial or required. It is important to follow specific steps and tips when handling armored cable:

If you are using type MC or BX cable, you must strip the armor before placing it in the conduit. This is necessary to ensure proper electrical bonding and safety. In some cases, such as when sleeving over a single conductor ground wire coming down a concrete wall headed to the water main, the armor may not need to be stripped entirely. However, the conduit must still be electrically bonded to the armor. Normally, stripping the armor before entering the conduit is recommended, leaving just enough to secure into the connector. At the box, use a regular EMT connector to secure the conduit to the box. This ensures a proper and secure connection.

Additional Considerations

It is important to note that electrical fittings and connectors can sometimes pose challenges when it comes to securing armored cable. For instance, using NM fittings on BX/MC cable may not provide a tight seal, which can be problematic. In such cases, specialized connectors or NM/EMT fittings are often more reliable and easier to work with.

Conclusion

In summary, while armored cable can often be used without conduit in certain applications, there are situations where using conduit is beneficial or required for safety and compliance reasons. Always consult local codes and regulations to ensure compliance and safety. Proper understanding and application of best practices can lead to successful and long-lasting electrical installations.