Electrical Pull Box Requirements

314 28 pull and junction boxes the national electrical code nec has specific requirements detailing how to calculate the maximum numbers of conductors in boxes outlet device junction pull etc and conduit bodies.

Electrical pull box requirements.

Chapter 3 of the national electrical code nec covers wiring methods and materials. Article 314 covers the installation and use of all boxes and conduit bodies used as outlet device junction or pull boxes depending on their use. The national electrical code nec mandates specific sizes for pull boxes determined primarily by the conduit or raceway sizes and pulling scheme. 314 28 pull and junction boxes.

Nec 314 16 wiring methods junction box fill the volume of electrical boxes shall be sufficient for the number of conductors devices and cable clamps contained within the box. Minimum distance from where conductors enter to the opposite wall cannot be less than eight times the trade size of the largest raceway. Calculating pull box enclosure sizes. And u pulls which turn 180 degrees to re enter the.

Straight pulls which travel straight through a pull box. 1 to illustrate how these requirements prevent conductor insulation damage let s consider two extremes in a straight pull situation. These boxes are calculated from the sizes and numbers of conductors. The answer to each question is offered up on a separate slide which follows.

The codes shown are examples only and may not be current or accurate for your application or jurisdiction. Provisions for boxes and conduit bodies enclosing conductors 18 awg through 6 awg are in 314 16. Shop for underground pull boxes in boxes enclosures from rexel usa where contractors and project managers can find the electrical underground pull boxes products they need for their projects. Three types of pulling schemes are used.

The sizing requirements for pull boxes junction boxes handhole enclosures and conduit bodies exist to prevent conductor insulation damage. The code quiz features three questions that are presented in a true false fill in the blank or multiple choice format. In this case simply multiply your largest raceway size by 8 and that will give you the minimum length for your box. Angle pulls which make a 90 degree angle.