This part of IEC 60051 applies to direct acting indicating analogue frequency meters of the following types:
• pointer-type frequency meters (as defined in 3.2.1 1 of IEC 60051 -1 :201 6);
• vibrating-reed frequency meters (as defined in 3.2.1 2 of IEC 60051 -1 :201 6).
This document also applies to non-interchangeable accessories (as defined in 3.1 .23 of IEC 60051 -1 :201 6) used with frequency meters.
