scope:

This part of IEC 60051 applies to direct acting indicating wattmeters and varmeters having an analogue display.

NOTE For multi-function instruments, see IEC 60051-7.

It also applies to:

• non-interchangeable accessories (as defined in 3.1.23 of IEC 60051-1:2016) used with wattmeters and varmeters;

• a combination of the instruments and the accessories provided that the adjustments have been made for the combination;

• direct acting indicating electrical measuring instruments whose scale marks do not correspond directly to their electrical input quantity, provided that the relationship between them is known;

• instruments and accessories having electronic devices in their measuring and/or auxiliary circuits.

This document does not apply to:

- special purpose instruments which are covered by their own IEC standards;

- special purpose devices which are covered by their own IEC standards when they are used as accessories.