IEEE 404-1986

IEEE 404-1986 is a standard for cable joints used with extruded dielectric cable rated 5000 V through 46 000 V and with laminated dielectric cable rated 2500 V through 500 000 V. It addresses the technical requirements for joining medium- and high-voltage power cables, helping ensure consistent electrical performance and installation practice. In power, energy, and related industrial applications, this document is useful for specifying suitable jointing methods and reducing the risk of incompatible or unreliable cable connections.

IEEE 404-1986 overview

This IEEE standard focuses on cable joints for two important insulation types: extruded dielectric cable and laminated dielectric cable. IEEE 404-1986 is intended to guide engineering and product selection where cable splices must maintain dielectric integrity across a defined voltage range. Its scope is practical rather than broad, concentrating on joints that can support service requirements in energized power distribution and transmission environments. For procurement, design review, and specification work, it provides a clear technical reference for cable-joint expectations.

Typical use cases

This standard is commonly relevant when specifying or evaluating joints for underground or aboveground power cables in utility, industrial, and large-facility electrical systems. It may be used for cable splicing projects involving feeders, substation connections, plant distribution circuits, or other installations where voltage rating and insulation type must match carefully. IEEE 404-1986 is especially useful when teams need to align joint design and installation requirements with the cable construction already in service.

Why this standard matters

Reliable cable joints are critical because a weak or poorly matched splice can compromise insulation performance, service continuity, and worker safety. IEEE 404-1986 helps support consistent design and specification decisions for joints used on rated power cables, reducing uncertainty during procurement, construction, and maintenance. It also gives engineers and inspectors a common basis for comparing products and installation methods, which can lower the risk of premature failure and improve long-term system reliability.

• Cable joints for extruded dielectric cable
• Cable joints for laminated dielectric cable
• Voltage ratings from 2500 V up to 500 000 V
• Power system splicing and connection applications
• Specification and compliance reference