phase unbalance protection
1защита от несимметрии фаз — [В.А.Семенов. Англо русский словарь по релейной защите] Тематики релейная защита EN phase unbalance protection …
2Uninterruptible power supply — A small free standing UPS …
3Mains electricity — A table lamp connected to a wall socket (the mains). Mains is the general purpose alternating current (AC) electric power supply. In the US, electric power is referred to by several names including household power, household electricity,… …
4List of IEC standards — In order to distinguish standards published by the International Electrotechnical Commission numerically from other international standards, their number range was shifted in 1997 by adding 60000. So what used to be called IEC 27 is now… …
