This International Standard applies to all line-commutated high-voltage direct current (HVDC) converter stations used for power exchange in utility systems. This standard presumes the use of 12-pulse thyristor converters but can, with due care, also be used for 6-pulse thyristor converters. This standard presents a set of standard procedures for determining the total losses of an HVDC converter station. The procedures cover all parts, and address no-load operation and operating losses together with their methods of calculation which use , wherever possible, measured parameters.