Grounding & Bonding 480/120/208 xfmr, 150KVa

Status
Not open for further replies.

gk351

Senior Member
Location
IL
I'm installing a 150KVa XFMR for an existing facilty that will be converted from 240 3 PHase to 208 Volt 3 Phase. I have a disco adjacent to the XFMR. From the 480V Disco, I used RMC as my conduit run, except a 1 ft piece of LFMC between the two. My new separately derived 208V system, will be adjacent to the XFMR, in the same manner as the primary side. It will feed a 400A Disconnect. The secondary run between the xfmr and the 400 A disco is made with RMC with a 1ft piece of LFMC in between the conduit run and the XFMR ( For vibration purposes.) My questions are. I still need an equipment ground ran with my 480V conductors to the XFMR, as well as a Supply side bonding jumper from the grounding bushing. Can I run all of these conductors to my XO connection? Must I only put my grounded(neutral) conductors on the XO terminal, along with the GEC, and SBJ? I'm just trying to save some time and lugs, as the XO connection is quite large and can handle these connections via bolted compression lugs. Any help with this would be appreciated, the 2011 Code has a bit confused. THx. GK
 

augie47

Moderator
Staff member
Location
Tennessee
Occupation
State Electrical Inspector (Retired)
I know of no reason you can not use the XO bar for all the connections.
(I may learn some :) )​
 

gk351

Senior Member
Location
IL
That was my conclusion. As long as everything is sized correctly(EGC, SSBJ. MBJ, GEC, etc, lol) I wouldn't see why alll connections couldn't be made to the nice and large XO bar. I feel it just saves time, and finding a lug assembly that will accept all the miscellaneous wire sizes that would bolt to the frame, just to be connected via the MBJ to the XO. Please anyone let me know if this is a no go!!
 

infinity

Moderator
Staff member
Location
New Jersey
Occupation
Journeyman Electrician
My questions are. I still need an equipment ground ran with my 480V conductors to the XFMR, {Probably} as well as a Supply side bonding jumper from the grounding bushing. {No bonding bushing required} Can I run all of these conductors to my XO connection? {Yes} Must I only put my grounded(neutral) conductors on the XO terminal, along with the GEC, and SBJ? I'm just trying to save some time and lugs, as the XO connection is quite large and can handle these connections via bolted compression lugs. Any help with this would be appreciated, the 2011 Code has a bit confused. THx. GK

You could save yourself some money and skip the bonding bushings. :)
 
Status
Not open for further replies.
Top