Direct acting indicating analogue electrical measuring instruments and their accessories - Part 3: Special requirements for wattmeters and varmeters
|Publication Date:||1 August 2018|
|ICS Code (Measurement of electrical and magnetic quantities):||17.220.20|
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.