At a former employer, I took the approach that this exemption is applicable ONLY when equipment is kept *by a public utility* within its own facility. Some made the argument that the exemption is available for utility company vaults and rooms inside customer buildings. I see where that interpretation might be made, but I think the INTENT of Part 15 requires this be evaluated case-by-case. In any event, relying on the exemption in all circumstances could in the end cost more than any cost edge from ignoring EMI/RFI.
The logic of the exemption, so far as I have been able to tell, is that equipment operated by a utility (which nowadays includes much more than Ma Bell and the Electric Company) in its own site creates interference that is not a problem for the public, and if tolerable by the user, is tolerable by the Commission. This does allow economies to be achieved in design IF the building, facility, vault, cabinet or room can provide shielding and filtering lacking in equipment. However, adding that shielding and filtering AFTER installation can cost in the end more than quiet equipment. Cortland Richmond ------------------------------------------- This message is from the IEEE EMC Society Product Safety Technical Committee emc-pstc discussion list. Visit our web site at: http://www.ewh.ieee.org/soc/emcs/pstc/ To cancel your subscription, send mail to: [email protected] with the single line: unsubscribe emc-pstc For help, send mail to the list administrators: Ron Pickard: [email protected] Dave Heald: [email protected] For policy questions, send mail to: Richard Nute: [email protected] Jim Bacher: [email protected] All emc-pstc postings are archived and searchable on the web at: http://ieeepstc.mindcruiser.com/ Click on "browse" and then "emc-pstc mailing list"
