Zapped if we go with the assumption that this feeds a trash compactor pump (or any equipment) and you want to use a flexible cord ,the closest article that would allow this would be 400.7(A)(6), but in order to be able to say it is for frequent interchange it needs to have an outlet and plug.
If you have to unwire the cord to change the equipment you could just as easily unwire a piece of LFMC.
400.7 Uses Permitted.
(A) Uses. Flexible cords and cables shall be used only for the following:
(6) Connection of utilization equipment to facilitate frequent interchange
But with the cord hardwired into the disconnect IMO it is a violation of 400.8(1) and (4)
400.8 Uses Not Permitted.
Unless specifically permitted in 400.7, flexible cords and cables shall not be used for the following:
(1) As a substitute for the fixed wiring of a structure
(4)Where attached to building surfaces
I have no doubt that concentric knockouts are a headache for the manufactures, set the dies to tight and the KOs will fall out, let them get to loose and the KOs are no more than an outline of the KOs that are not removable with a sledge hammer.
I think a big problem with premade KOs is that they often end up half way in the way, so when you punch a hole where you want you end up with a hole resembling an 8.
[This message has been edited by iwire (edited 10-04-2003).]