Neutral bonded to enclosure at both places?

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Tainted

Tainted

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New York
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Engineer (PE)
I went to a building that had a main service switchboard with 5 service switches. I wasn't able to open up to look inside of the switchboard but I'm assuming it has a main bonding jumper and all the neutrals are bonded to the enclosure.

There is a 200A service switch in the switchboard that is feeding a standalone CT cabinet next to the switchboard. I open up the CT cabinet and it had a neutral bonded to the enclosure.

Would it be against code to bond the neutral to the enclosure in both places such as switchboard and the CT cabinet? Should it only be bonded in one place such as the switchboard?
 
If the CT cabinet is on the load side of the service equipment, the neutral is not permitted to be connected to the CT enclosure. it needs an EGC from the service equipment.

CT cabinets on the line side of the service equipment can have their enclosures connected to the neutral as the neutral is permitted to be used for all required grounding and bonding on the line side of the service equipment.
 
don_resqcapt19 said:
If the CT cabinet is on the load side of the service equipment, the neutral is not permitted to be connected to the CT enclosure. it needs an EGC from the service equipment.

CT cabinets on the line side of the service equipment can have their enclosures connected to the neutral as the neutral is permitted to be used for all required grounding and bonding on the line side of the service equipment.
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Ok, so you’re saying that bonding the neutral and enclosure can be done in both places at once only if the CT is ahead of the service switch?
 
Tainted said:
Ok, so you’re saying that bonding the neutral and enclosure can be done in both places at once only if the CT is ahead of the service switch?
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In and ahead of the service main there is no EGC; everything is bonded to the neutral.
 
There are some factory assembled CT/meter cabinets with a bonded neutral. I think it's a stretch of a Code exception but depending on the circumstances (such as a factory assembly) an inspector might employ Excception 2 to 250.142
 
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