I believe they're referring to large switchboard-style cabinets.
409.2 defines "Industrial control panel" and refers to pretty much anything, including breaker panels, switchgear, MCC, pushbuttons, etc. 409.60 just wants to make sure you properly bond them all together if they're installed as a single multisection unit. If you mount individual industrial control panels 1" apart, I do not believe 409.60 applies.
Edit: 409.2 was re-written in 2008, but doesn't appear to really change the definition, just presents it differently.
Last edited by SteveFehr; 02/12/08 06:33 AM.