[电] phase-balance current relay
xiàng wèi píng héng diàn liú diàn yì ㄒㄧㄤˋ ㄨㄟˋ ㄆㄧㄥˊ ㄏㄥˊ ㄉㄧㄢˋ ㄌㄧㄡˊ ㄉㄧㄢˋ ㄧˋ