Rockwell Automation 1756-CNB ControlLogix ControlNet Bridge Module, Series E Installation Instructions - Manual (Page 14)

14 ControlLogix ControlNet Interface Module
Publication 1756-IN604A-EN-P - February 2006
Install or Remove the Module Under Power
You can install or remove the module while chassis power is applied if you
observe the following precautions.
WARNING
When you insert or remove the module while backplane power is on,
an electrical arc can occur. This could cause an explosion in hazardous
location installations.
Be sure that power is removed or the area is nonhazardous before
proceeding. Repeated electrical arcing causes excessive wear to
contacts on both the module and its mating connector. Worn contacts
may create electrical resistance that can affect module operation.