During testing a managed Ethernet Switch we found a possible mistake in the IEC 61850-3 (2002). This standard requires in clause 5.8 that communications equipment shall meet the requirements of CISPR 22 classes A and B or FCC rules part 15 for classes A and B digital devices.
This is not a normal way of specifying conducted and radiated disturbances. Normally class A or(!) B is specified. In case class A and B is specified than normally the environment where the equipment may be used is specified.
For instance IEC 60870-2-1 "Telecontrol equipment and system - part 2: Operating conditions - Section 1: Power supply and electromagnetic compatibility" described that class A applies to equipment used in control centers, controlled stations and remote terminal units, located in industrial or electrical plants. Class B applies to equipment used in control centers, controlled stations and remote terminal units, installed in locations other that those specified for class A.
Clarify when/where/in which environment requires "Class A". Same for "Class B". Replace "Class A and B" by "Class A or B"