GB/T 3926-2007 in English

本标准规定了中频设备的额定电压及电压偏差限值。
本标准适用于单相和三相交流频率高于工频50Hz，不超过10kHz范围内的航空、航天、舰船电气设备和一般工业电气设备的额定电压。

Scope

This standard specifies the rated voltage and voltage deviation limits of intermediate frequency equipment. This standard is applicable to the rated voltage of aviation, aerospace, marine electrical equipment and general industrial electrical equipment within the range of single-phase and three-phase AC frequency higher than 50 Hz and not exceeding 10 kHz. General industrial electrical equipment includes: general electrical equipment, electric heating equipment, electrical equipment for machine tools, textile motors, control micro motors, electric tools, intermediate frequency generators, static inverters and intermediate frequency mobile power equipment, etc. This standard does not apply to, but is not limited to, the following equipment: a) AC electrical equipment with stepless or step-adjustable frequency; b) Excitation equipment for generators; c) Ship and aviation AC electrical equipment powered by variable voltage devices ; d) Internal circuits of remote communication, remote control, telemetry and communication (wired communication, wireless communication) equipment; e) Channel signals, automatic blocking devices and internal control circuits of electric locomotives; f) Internal control circuits of a single or a group of machine tools ; g) Power generation and consumption equipment with a rated frequency of 60 Hz.