hhsting
Senior Member
- Location
- Glen bunie, md, us
- Occupation
- Junior plan reviewer
Would not NEC 2017 Article 250.21(A)(3) apply AC systems 50V to 1000V not required to be grounded? This is control transformer
480V to 120V single phase transformer
- Thread starter hhsting
- Start date
Would not NEC 2017 Article 250.21(A)(3) apply AC systems 50V to 1000V not required to be grounded? This is control transformer
busman
Senior Member
- Location
- Northern Virginia
- Occupation
- Master Electrician / Electrical Engineer
From 90.6:
It is the intent of this Code that factory-installed internal wiring
or the construction of equipment need not be inspected at the
time of installation of the equipment, except to detect alterations
or damage, if the equipment has been listed by a qualified electrical
testing laboratory that is recognized as having the facilities
described in the preceding paragraph and that requires suitability
for installation in accordance with this Code.
hhsting
Senior Member
- Location
- Glen bunie, md, us
- Occupation
- Junior plan reviewer
What if the transformer in question has terminal for GEC provided by manufacturer? Would then GEC be required? Thats the topic I am talking about and code referenced my previous post
- Location
- New Jersey
- Occupation
- Journeyman Electrician (retired)
No. This is listed equipment and what's inside of listed equipment is not of any concern to an inspector unless there is a requirement in the instructions as part of the listing.
Strathead
Senior Member
- Location
- Ocala, Florida, USA
- Occupation
- Electrician/Estimator/Project Manager/Superintendent
If the manufacturer's instruction told you to connect a GEC then yes. You have to follow all manufacturer's instructions. If it doesn't specifically tell you that a GEC must attach to that point, then no.
- Location
- Illinois
- Occupation
- retired electrician
I would assume that it is factory bonded and it would be in compliance with 250.30(A)(4) Exception.