Replacement This part of IEC 60092 is applicable to low-voltage switchgear and controlgear assemblies [type-tested assemblies (TTA), partially type-tested assemblies (PTTA) and non type-tested assemblies (NTTA)], with rated voltages not exceeding 1 000 V a.c. at rated frequencies not exceeding 60 Hz or 1 500 V d.c. for use in ships as a supplement to IEC 60439-1. NOTE – Throughout this standard, the word ASSEMBLY is used for a low-voltage switchgear and controlgear assembly. This standard also applies to ASSEMBLIES incorporating control and/or power equipment, which operate at higher frequencies. In this case, appropriate additional requirements apply. Unless otherwise specified in the following clauses, all ASSEMBLIES and their components comply with IEC 60439-1. In case of doubt, IEC 60092 publications shall have preference over IEC 60439-1.