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计算题：某直流供电系统，负载电流750A，蓄电池两组，每组容量1000AH，开关电源选用48V/100A整流模块。求：①按目前负载情况，应该选用多少整流模块？②各整流模块限流设定值？（蓄电池充电电流取0.1C10）

答案

参考答案：

①直流系统的总负载I总＝负载电流＋蓄电池组充电电流＝750＋0.1×1000×2

＝950（A）

②需要整流模块个数N＝I总/开关电源额定电流＝950/100＝9.5（个）

＝取10（个）

③直流系统应该选用多少整流模块

根据N＋1配置，直流系统应该选用整流模块＝N＋1＝11（个）

④各整流模块限流设定值

I限＝I总/（N+1）＝950/11＝86.36（A）＝取87（A）

按目前负载情况，应该选用11个整流模块；各整流模块限流设定值为87A。

选择题

某未知溶液中已检验出含有离子Ca2+、NO3－，且pH=2。欲检验此溶液中是否大量存在以下6种离子：①ClO－②NH4+ ③Fe3+ ④I－ ⑤[Al(OH)4]－ ⑥Cl－，其中不必检验就能加以否定的离子是

A．③⑤⑥

B．④⑤⑥

C．①③④

D．①④⑤
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填空题

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