1 Scope and object
This part of IEC 60255 is applicable to measuring relays and protection equipment for power system protection,
including the control, monitoring and process interface equipment used with those
systems.
This standard specifies the essential requirements for electromagnetic compatibility
for measuring relays and protection equipment intended to be used at industrial locations.
Measuring relays and protection equipment used in substations and power plants may
require higher immunity test levels.
For equipment not incorporating electronic circuits, for example electromechanical
relays, tests according to this standard are not required.
The requirements specified in this standard are applicable to measuring relays and
protection equipment in a new condition and all tests specified are type tests only.
1.1 Emission
The object of this standard is to specify limits and test methods, for measuring relays
and protection equipment in relation to electromagnetic emissions which may cause
interference in other equipment.
These emission limits represent electromagnetic compatibility essential requirements
and have been selected to ensure that the disturbances generated by measuring relays
and protection equipment, operated normally in substations and power plants, do not
exceed a level which could prevent other equipment from operating as intended.
Test requirements are specified for the enclosure and power supply ports.