Supply side bonding jumper

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It would be quite rare to be in a situation where one could use a screw as a SSBJ, although there is no definition of a SSBJ in the NEC (unless they've added one after 2014?). Say one had a neutral terminal bar attached to a service pull box or trough. Could the screw holding that bar to the box be considered an SSBJ?
 
electrofelon said:
It would be quite rare to be in a situation where one could use a screw as a SSBJ, although there is no definition of a SSBJ in the NEC (unless they've added one after 2014?). Say one had a neutral terminal bar attached to a service pull box or trough. Could the screw holding that bar to the box be considered an SSBJ?
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"250.2 SSBJ A conductor................................."
 
electrofelon said:
It would be quite rare to be in a situation where one could use a screw as a SSBJ, although there is no definition of a SSBJ in the NEC (unless they've added one after 2014?). Say one had a neutral terminal bar attached to a service pull box or trough. Could the screw holding that bar to the box be considered an SSBJ?
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I'd say if designed and listed that way yes.

Midwest terminal boxes we use often on farms have terminals mounted in insulating blocks. They come with a copper bonding jumper, probably about a 2 AWG solid copper conductor in most 200 amp versions and a lug bolted to the box to land it in. That lug is only tapped into the box with a 10-32 screw though. Never seen one burn off, but have seen 1/4 bond screws in 200 amp panelboard neutral bus burn off where tapped into enclosure, probably because they were not properly tightened.
 
electrofelon said:
It would be quite rare to be in a situation where one could use a screw as a SSBJ, although there is no definition of a SSBJ in the NEC (unless they've added one after 2014?). Say one had a neutral terminal bar attached to a service pull box or trough. Could the screw holding that bar to the box be considered an SSBJ?
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I have neutral terminal in splice box line side of service trough. The trough feeds multiple disconnect enclosures downstream. Grounding electrode system would be at this splice box neutral bar. Neutral bar needs to be bonded to enclosure. Dont follow would a screw holding bar considered SSBJ?


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kwired said:
I'd say if designed and listed that way yes.

Midwest terminal boxes we use often on farms have terminals mounted in insulating blocks. They come with a copper bonding jumper, probably about a 2 AWG solid copper conductor in most 200 amp versions and a lug bolted to the box to land it in. That lug is only tapped into the box with a 10-32 screw though. Never seen one burn off, but have seen 1/4 bond screws in 200 amp panelboard neutral bus burn off where tapped into enclosure, probably because they were not properly tightened.
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It was a while ago, but I am pretty sure I did 1000 amp CT cabinet that had an isolated neutral bar, and a screw could be used to bond it to the cabinet like in a typical load center. I would say that is a SSBJ per Augies definition.
 
electrofelon said:
It was a while ago, but I am pretty sure I did 1000 amp CT cabinet that had an isolated neutral bar, and a screw could be used to bond it to the cabinet like in a typical load center. I would say that is a SSBJ per Augies definition.
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And that screw was probably designed and tested for the application, you can't just put any screw in there. Just like the screws that are used to bond panelboard neutral assemblies.

If the grounded bus is factory bolted directly to the enclosure it is probably already considered bonded. If you are installing your own lug, bar, etc, you probably need to remove paint where applied, and possibly even put a screw/bolt all the way through with a nut on back side - then the lug/bar contact with the enclosure is your bonding and the bolt is just securing it.
 
kwired said:
And that screw was probably designed and tested for the application, you can't just put any screw in there. Just like the screws that are used to bond panelboard neutral assemblies.
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But that section the OP just mentioned, 250.102, says bonding jumper can be a screw. I guess they say "screw" they are referring to "Factory" bonding jumpers by this? I dont see any way to size a screw in 250.102(C)
 
hhsting said:
I have neutral terminal in splice box line side of service trough. The trough feeds multiple disconnect enclosures downstream. Grounding electrode system would be at this splice box neutral bar. Neutral bar needs to be bonded to enclosure. Dont follow would a screw holding bar considered SSBJ?


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Don't make this anymore complicated than needed. Just bolt a multi port lug with enough ports for your neutrals and GEC directly to the wireway. If you need more ports you can stack another multi port lug on top. They just need to all be stacked with one bolt attaching them so you are not using the enclosure as a conductor. No bonding jumper needed.
 
texie said:
Don't make this anymore complicated than needed. Just bolt a multi port lug with enough ports for your neutrals and GEC directly to the wireway. If you need more ports you can stack another multi port lug on top. They just need to all be stacked with one bolt attaching them so you are not using the enclosure as a conductor. No bonding jumper needed.
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Don’t the enclosure which is metal and on line side of service disco need to be bonded to neutral which is my grounded conductor?


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hhsting said:
Don’t the enclosure which is metal and on line side of service disco need to be bonded to neutral which is my grounded conductor?


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Just bolt the lug(s) directly to the enclosure. The neutral is now bonded to the enclosure.
 
I can't think of any application where the supply side bonding jumper could be a screw. Are you really asking about a system bonding jumper?
 
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