Mike Dolt Enterprises
Mike Dolt Enterprises
User: anbm, Location: here
Asked on: Wednesday, April 13, 2011 at 6:30 pm EDT
Answered on: Tuesday, May 14, 2024 at 4:09 am EDT
Question: I noticed that NEC Exhibit 700.3 picture, looks like NEC requires physical separate vertical section for each feeder to feed ATS.We used a standard distribution panel to feed (3) ATSs (emergency, legally standby and optional standby) all the time... Will this comply with code for separate section listed above ??? I am confused, someone helps, please!
NEC Exhibit 700.3 Picture Interpretation
The picture in NEC Exhibit 700.3 does not explicitly require separate vertical sections for each feeder to an ATS. It shows a typical configuration where each ATS is fed by a separate feeder, but this is not a mandatory requirement.
Code Compliance of Standard Distribution Panel
NEC 700.3(B) states that "Each supply shall be connected to the transfer switch by a separate set of conductors." However, it does not specify that these conductors must be installed in separate vertical sections.A standard distribution panel can be used to feed multiple ATSs if the following requirements are met: Each ATS is connected to the panel by a separate circuit breaker or fuse. The panel has sufficient capacity to handle the combined load of all ATSs.* The conductors from the panel to each ATS are sized and installed according to NEC requirements.
Conclusion
Using a standard distribution panel to feed multiple ATSs is generally acceptable according to the NEC, provided that the above requirements are met. The NEC does not require separate vertical sections for each feeder to an ATS. Flag for review