Seperately derived systems / Neutral Bonding

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Seperately derived systems / Neutral Bonding
I have typical 225KVA 480/120/208 transformer serving a fusible disconnect on its secondary, ultimately feeding a few 208/120V panel boards.

I have bonded the neutral XO tap in the transformer to the grounding lug within, along with my GEC to building Steel.

Question: the disconnect is my 1st means of disconnect. Do I need to re-bond the neutral in the disconnect to the grounding buss or shall I float the neutral?

Thanks in Advance​
 
No. You only bond once. Neutral and ground must be separated in the disconnect and anywhere else downstream of the bond in the xfmr.
 
The SBJ goes at the transformer or first disconnecting means but not both. The GEC connection is made where the SBJ is installed.
 
Which also means you need a supply side bonding jumper between the transformer and the disconnecting means to serve as a grounding means for the disconnect.
 
Typically you install a system bonding jumper (SBJ) at either the transformer or the first disconnecting means and run a supply-side bonding jumper (SSBJ) between the two. Wherever the SBJ is installed is where you also connect your GEC/GES. However, you have another choice if there are no metallic pathways between the transformer and disconnecting means other than the grounded conductor. Under this exception, you can install an SBJ at both locations and not run an SSBJ. See 250.30(A)(1) Exception No. 2.

Note under 2014 the transformer is required to be outdoors.
 
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You would need a solid neutral block in the disconnect. This totally isolates the neutral from ground. Terminate the neutral from the transformer onto this, and then if you want to carry it on, terminate the load side neutral to wherever you are heading to...ie panel
 
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