Objectionable current

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Magnetic forces are churned up during faults on service equipment at least in some cases. Things can come apart that would not under normal conditions, and service equipment has been known to pull free from the surface to which it has been fastened to. Seems fairly objectionable to me.
 
macmikeman said:
Magnetic forces are churned up during faults on service equipment at least in some cases. Things can come apart that would not under normal conditions, and service equipment has been known to pull free from the surface to which it has been fastened to. Seems fairly objectionable to me.
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Fault current is not considered objectionable current in the NEC. See 250.6(C)

250.6 Objectionable Current.
(A) Arrangement to Prevent Objectionable Current.
The grounding of electrical systems, circuit conductors,
surge arresters, surge-protective devices, and conductive
normally non?current-carrying metal parts of equipment
shall be installed and arranged in a manner that will prevent
objectionable current.
(B) Alterations to Stop Objectionable Current. If the
use of multiple grounding connections results in objectionable
current, one or more of the following alterations shall
be permitted to be made, provided that the requirements of
250.4(A)(5) or (B)(4) are met:
(1) Discontinue one or more but not all of such grounding
connections.
(2) Change the locations of the grounding connections.
(3) Interrupt the continuity of the conductor or conductive
path causing the objectionable current.
(4) Take other suitable remedial and approved action.
(C) Temporary Currents Not Classified as Objectionable
Currents. Temporary currents resulting from accidental
conditions, such as ground faults, shall not be classified
as objectionable current for the purposes specified in
250.6(A) and (B).
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