Mike Dolt Enterprises
Mike Dolt Enterprises
User: faresos, Location: Massachusetts
Asked on: Monday, March 21, 2011 at 10:02 am EDT
Answered on: Tuesday, May 14, 2024 at 3:03 am EDT
Question: Hello every one....I have a situation where there is a large thick concrete pad that the owner wants to build a 7,000sf modular building on it (almost like a trailer type). The building will be standing on 3'-0" pedestals. The the building will be located 20'-0" of the edge of the concrete pad. The main service switchboard will be located in the building, the service transformer is located outside the pad area. My approach to bring the service to the building by running (3) sets of 4" conduit and set a pull box by the edge of the concrete and go above the concrete pad for 20ft and turn it up to the main switchboard. My understanding we can not run these feeders unprotected. so, to protect these feeders, I will be using some kind of precast concrete covers (2" min) along the feeders above the pad. my question is, is there any code violation by doing this or if I'm missing something like I don't need to protect these feeders since they are not running exposed within the building . Thanks in advance for your thoughts
Code Requirements
2020 National Electrical Code (NEC) Article 300.4(E)
Protected Conductors Not in Raceway. Conductors shall be protected from physical damage by at least one of the following means: Rigid metal conduit (RMC) Intermediate metal conduit (IMC) Electrical metallic tubing (EMT) Schedule 80 PVC conduit Other approved means
Your Approach
Your approach of using precast concrete covers to protect the feeders above the concrete pad is in accordance with
NEC 300.4(E). Precast concrete covers provide adequate physical protection against potential damage.
Code Violation
There is
no code violation by using precast concrete covers to protect the feeders.
Additional Considerations
Ensure that the precast concrete covers are properly secured and provide continuous protection along the length of the feeders. Consider using a sealing compound or sealant between the concrete covers and the concrete pad to prevent moisture ingress.* Comply with all applicable building codes and requirements regarding the installation of precast concrete covers.
Alternate Option:
Another option to consider is running the feeders in a conduit embedded within the concrete pad. This provides even greater protection against physical damage, but it may be more challenging and expensive to install. Flag for review