Article 310.10 Interpretation

[tmalzahn]

We have an issue where our incoming service conductors (24.9kV) enter the building at an expansion joint with movemetn +-2" in both the x and y directions. We would like the conduits leaving the exterior junction boxes to not be rigidly attached to the box but bond the conduits to the box for continuity. Below is a sketch of what we would like to do, does anyone see this as an acceptable variance to the requirements of 300.10?

 

[jusme123]

they want $ 3,000 for this fitting :lol:




http://www.cooperindustries.com/con...iondeflectioncouplingsandexpansionjoints.html

 

[tmalzahn]

This fitting does not accommodate the +-2" of movement in the Y direction (parallel to the wall.) We have gotten the supplier to agree that if we put two Deflection fittings in series with an unsupported conduit between the two fittings that we can safely assume angular deflection rather than parallel misalignment. At about $1000 a fitting this solution gets expensive fast as there are 24 conduits with this condition.

 

[jusme123]

...what is the distance between the outside box and the interior box in the pic?

 

[Dennis Alwon]

Would using some flexible conduit or cable work?

 

[tmalzahn]

In some instances only 2'. Those conduits are 4".

For the particular instance in the image i belive it is about 8'. There is flexbility with this box location.