理光低压膜式家用燃气流量表正常计量压力为()。
A.500±50mm H20
B.1000±100mm H20
C.280±50mm H20
D.100±10mm H20
参考答案:C
— Hello, John.
—Oh, Mike! I _____ to meet you here.[ ]
A. won't expect
B. haven't expected
C. don't expect
D. didn't expect
为什么110KV及以上电压互感器二次回路要经过一个隔离开关的辅助接点?