200.3?
- Thread starter bennie
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Re: 200.3?
The reason I asked is because I have a book describing the original reason.
The reason as stated in the 1930's, when this first appeared has apparently been changed.
The reason was to prohibit the installation of an auto-transformer as a balance coil to derive a three wire system.
All reference to this was removed from the code book in 1975.
The reason I asked is because I have a book describing the original reason.
The reason as stated in the 1930's, when this first appeared has apparently been changed.
The reason was to prohibit the installation of an auto-transformer as a balance coil to derive a three wire system.
All reference to this was removed from the code book in 1975.
Re: 200.3?
I have discovered the reason for removing the section about auto-transformers. It was done due to the use was discontinued anyway. Standard two winding transformers replaced them.
200.3 Is to assure the utility MGN is connected to the X-O of the premises system, for the purpose of winding to winding faults.
I have discovered the reason for removing the section about auto-transformers. It was done due to the use was discontinued anyway. Standard two winding transformers replaced them.
200.3 Is to assure the utility MGN is connected to the X-O of the premises system, for the purpose of winding to winding faults.
Re: 200.3?
I have been partly corrected in my previous explanation of my interpretation of 200.3.
A grounded premises wiring system can not be electrically connected to an ungrounded supply, except by magnetic coupling.
Electrically connected shall mean capable of carrying current.
I have been partly corrected in my previous explanation of my interpretation of 200.3.
A grounded premises wiring system can not be electrically connected to an ungrounded supply, except by magnetic coupling.
Electrically connected shall mean capable of carrying current.
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