Rockwell Automation DeviceNet Media Design Installation Guide - Manual (Page 115)

1 Publication DNET-UM072C-EN-P - July 2004
Appendix
A
Understand Select NEC Topics
Be aware that the following topics from the National Electrical Code (NEC)
725 (revision 1999) impact the configuration and installation of DeviceNet
systems in the United States. There also may be additional NEC sections and
local codes that you must meet. Other codes exist outside of the United States
that may also affect your installation.
Specify Article 725 Topics Round (thick & thin) and Class 2 flat media
Power limitations of Class 2 circuits
The power source for Class 2 circuits must be either inherently limited, thus
requiring no overcurrent protection, or limited by a combination of a power
source and overcurrent protection.
Marking
Class 2 power supplies must be durably marked where plainly visible to
indicate the class of the supply and its electrical ratings.
Interconnection of power supplies
Class 2 power supplies must not be paralleled or otherwise interconnected
unless listed for such applications.
Class 1 flat media
Power limitations of Class 1 circuits
• The overcurrent protection shall not exceed 10 amperes per NEC article
725-23.
• Consult the product manufacturer to determine if the device is suitable
for installation with a Class 1 power source.