SDS/Transformer System Bonding Jumper

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SDS/Transformer System Bonding Jumper

  • Install at transformer

    Votes: 8 80.0%

  • Install at OCPD enclosure

    Votes: 2 20.0%
  • Total voters
    10
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infinity

infinity

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Journeyman Electrician
I'm looking for opinions on the best place to install the system bonding jumper in a separately derived system (transformer). I've always installed them inside the transformer enclosure but was wondering if there is an advantage to installing them at the OCPD enclosure for the secondary conductors. Any opinions?
 
It would be based on which is closer to the grounding electrode for me. There is no other difference, so minimize the cost of the GEC.
 
iwire said:
I think if you keep such accurate statistics of your work you may want to seak some OCD help.:)
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:rotflmao:






Now that I've recovered, I should note the level of precision was only for emphasis. I do not keep records on the matter ;)
 
don_resqcapt19 said:
It would be based on which is closer to the grounding electrode for me. There is no other difference, so minimize the cost of the GEC.
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So what about also minimizing the use of supply side bonding jumpers in the secondary raceways? Would that also be a consideration? Seems to me that if you install the system bonding jumper at the enclosure containing the OCPD then you eliminate the SSBJ in each raceway(s) that have the secondary conductors installed.
 
infinity said:
So what about also minimizing the use of supply side bonding jumpers in the secondary raceways? Would that also be a consideration? Seems to me that if you install the system bonding jumper at the enclosure containing the OCPD then you eliminate the SSBJ in each raceway(s) that have the secondary conductors installed.
Click to expand...

Installing the grounded/grounding bond in the tranny would increase the use of EGC, not SBJ no? Since the secondary OCPD is installed right next to the tranny, the cost of the aditional EGC is more often than not fairly insignificant.
 
There is a supply side bonding jumper between the transformer and the first disconnect no matter where the system bonding jumper is installed.

The OCPD could be 25' away, but after more thought, it doesn't make any difference as the supply side bonding jumper and the GEC would be the same size, so there is no savings either way.
 
don_resqcapt19 said:
... it doesn't make any difference as the supply side bonding jumper and the GEC would be the same size, so there is no savings either way.
Click to expand...
It does make a difference. Running the GEC to the closer equipment would use less wire. There is a grounding conductor between xfmr and system disconnecting means (SDM) regardless where the SBJ/GEC connections are made... right?

For example, let's say your SDM is 25' away and mounted on building steel that qualifies as a GE. The tranny is further away from any GE.
 
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