This part of IEC 61375 applies to all equipment and devices implemented according to IEC 61375-3-1, i.e. it covers the procedures to be applied to such equipment and devices when the conformance should be proven. The applicability of this standard to a TCN implementation allows for individual conformance checking of the implementation itself and is a pre-requisite for further interoperability checking between different TCN implementations. NOTE 1 An example of TCN implementation is given in UIC 556.