直接作用指示模拟电测量仪器及其附件 第3部分：瓦特表和电压表的特殊要求

[中文适用范围]： IEC 60051 的这一部分适用于具有模拟显示器的直接作用指示功率表和无功功率表。注 对于多功能仪器，请参阅 IEC 60051-7。它还适用于： 与功率表和无功功率表一起使用的不可互换附件（如 IEC 60051-1:2016 的 3.3 中定义）；仪器和附件的组合，前提是该组合已进行调整；直接作用指示式电气测量仪表，其刻度标记与其电气输入量不直接对应，但前提是它们之间的关系已知；在其测量和/或辅助电路中具有电子设备的仪器和附件。本文件不适用于；其自己的 IEC 标准涵盖的特殊用途仪器；特殊用途设备在用作附件时受其自己的 IEC 标准涵盖。 [外文原描述]： IEC 60051-3:2018 applies to direct acting indicating wattmeters and varmeters having an analogue display. IEC 60051-3:2018 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. IEC 60051-3:2018 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. IEC 60051-3:2018 cancels and replaces the fourth edition published in 1984 and Amendment 1:1994. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) updating of content in line with new editions of IEC 60051-1 and IEC 60051-9; b) addition of Annex A to specify the nonconformity classification of test items. IEC 60051-3:2018 is to be used in conjunction with IEC 60051-1:2016.