This part of IEC 60255 specifies minimum requirements for over/under current relays. This
standard includes a specification of the protection function, measurement characteristics and
time delay characteristics.
This part of IEC 60255 defines the influencing factors that affect the accuracy under steady
state conditions and performance characteristics during dynamic conditions. The test
methodologies for verifying performance characteristics and accuracy are also included in this
standard.
BS EN 60255-151:2009 history
2014BS EN 60255-127:2014 Measuring relays and protection equipment. Functional requirements for over/under voltage protection
1998BS EN 60255-3:1998 Electrical relays - Single input energizing quantity measuring relays with dependent or independent time