# Disconnects for Transformer Secondary



## Magnettica (Jan 23, 2007)

Which code section did you hear about this 4-disconnect rule?


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## HARRY304E (Sep 15, 2010)

cornergrounded said:


> First time so please be gentle:


How about a little Pain.!..:boxing::boxing::laughing:

Welcome to the forum..:thumbup:



cornergrounded said:


> This question came to me from a colleague over the phone:
> 
> The secondary on a 200kva transformer has four loads each with it's own disconnect. Is this up to code or should there be just one disconnect for all ungrounded conductors? Meaning he should have one "main" disconnect for the four loads then branch out from there or is he good with the four seperate disconnects. I'm thinking he is good if I understand the code right just as long as all four disconnects are in one location?



Take a look at this section of the code..

*II. Location
240.21 Location in Circuit.* Overcurrent protection shall
be provided in each ungrounded circuit conductor and shall
be located at the point where the conductors receive their
supply except as specified in 240.21(A) through (H). Conductors
supplied under the provisions of 240.21(A) through (H)
shall not supply another conductor except through an overcurrent
protective device meeting the requirements of 240.4.



.


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## wildleg (Apr 12, 2009)

Magnettica said:


> Which code section did you hear about this 4-disconnect rule?


table 450 3 A Note 2 (6 disconnect rule for secondary transformer protection)

(as harry noted, 240.4G points to the table in 240.4 which also points you to 450)


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## cornergrounded (Apr 3, 2013)

Right at Magnettica, 450.3 note 2 is what i was looking at when thinking he was good with that configuration as all the DC's are in one location and only four of them and the the note states that up to six are permissable. 

Harry304E thanks for the welcome.


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