Disconnect Switch Secondary Side Xfrmr

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mstrlucky74

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NJ
Ok the secondary side conductors are feeding a panel 200 feet away so disconnect is needed if I'm reading 1-6 correctly. Transformer is delta to wye
 
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petersonra

Senior Member
Location
Northern illinois
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engineer
Ok the secondary side conductors are feeding a panel 200 feet away so disconnect is needed if I'm reading 1-6 correctly. Transformer is delta to wye

a disconnect is not required on the secondary side, however it often works out that it is a convenient place to put the OCPD that may be required.

you might also need it for other reasons, such as the disconnect feeding a separate structure.
 

jumper

Senior Member
But we are trying to determine if a mcb in the panel 200' away can serve as the means of disconnect. Some are saying not because of he distance away from the transformer.

As stated above, what you need is protection of the secondary conductors and your breaker is too far away, so you need a disconnect that provides protection/OCP for the conductors not the xfrmr.
 

infinity

Moderator
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Location
New Jersey
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Journeyman Electrician
But we are trying to determine if a mcb in the panel 200' away can serve as the means of disconnect. Some are saying not because of he distance away from the transformer.

You need to have the OCPD with no more than 25' of the secondary conductor length so no 200' away won't work with a main in the panel.
 

GoldDigger

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So the disco has to be within 25' of the transformer and not at the panel 200' away? Thx
The issue is not the disco itself but the overcurrent protection it provides for the wires.
Until they reach an OCPD the wires are taps and subject to the applicable tap rules. That is the issue, not the disconnecting of the circuit.
 

infinity

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Location
New Jersey
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The secondary conductors require over current protection within 25' of their origin at the transformer. They do not require a disconnecting means although a fused disconnect would accomplish both of those actions.
 
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