Buck-boost transformer
- Thread starter j rae
- Start date
- Status
- Location
- Massachusetts
It is allowed.
As far as an Article number I can't give you one that allows it but more importantly there is no Article prohibits it.
What are you specifically concerned with?
As far as an Article number I can't give you one that allows it but more importantly there is no Article prohibits it.
What are you specifically concerned with?
A/A Fuel GTX
Senior Member
- Location
- WI & AZ
- Occupation
- Electrician
More information please....
1. Who is the "company", the manufacturer of the equipment or the electrician doing the installation?
2. Is the "panel" the loadcenter or a panel associated with the equipment?
- Location
- Massachusetts
You have peaked my curiosity why either of these question would impact the answer.
A/A Fuel GTX
Senior Member
- Location
- WI & AZ
- Occupation
- Electrician
You have peaked my curiosity why either of these question would impact the answer.
Just curious if a field modification was done or if it was an OEM situation.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
A buck - boost is an autotransformer. There are couple sections in art 450 that refer to autotransformers. None of what you have mentioned is part of topic in those sections.
There were several hits in a search of the word autotransformer - the most relevant besides the ones in art 450 that deal directly with what your topic of discussion is exception 1 to 210.9. Same exception appears after 215.11.
Exception No. 1: An autotransformer shall be permitted without the connection to a grounded conductor where transforming from a nominal 208 volts to a nominal 240-volt supply or similarly from 240 volts to 208 volts.
I am concerned about it going back through the panel then to the recptical. This is not an OEM item this was installed after the equipment by a contractor.
You have peaked my curiosity why either of these question would impact the answer.
The contractor installed the transfoirmer alongside the panel then feeds the recptical. 208v. in 240v out.
copper chopper
Senior Member
- Location
- wisconsin
is the transformer on a breaker? are the amprages correct for the installation? what are the nameplate ratings on that piece of equipment that the transformer is for?
take pictures man and get back to us..
take pictures man and get back to us..
- Location
- Illinois
- Occupation
- retired electrician
Take a look at 312.8 and if you are not looking at the 2011 code, make sure that you read the complete section.
kwired
Electron manager
- Location
- NE Nebraska
- Occupation
- EC
Like Don said it is permitted, if you are concerned about a live conductor originating outside the panel - that is not really what we have here - if you turn off the supply to the panel - there will be no voltage to feed back into the panel.
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