单选题当照明负载采用星形连接时,必须采用()。A三相三线制B三相四线制C单相制D任何线制
单选题
当照明负载采用星形连接时,必须采用()。
A
三相三线制
B
三相四线制
C
单相制
D
任何线制
参考解析
解析:
暂无解析
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