备用停机情况下密封油系统的运行注意事项？
参考答案：
⑴最低发电机氢压不得低于0.14MPa，以免影响密封油系统运行；最高氢压不必高于0.25MPa，以免增加漏氢量；
⑵氢压可能变动较大，氢压变动过程中注意氢侧油箱油位、油氢差压稳定正常，并及时调整氢侧母管油压，维持正常的空、氢侧油压差，以免影响氢纯度；
⑶空侧直流油泵是第一备用，高压备用油不再是第一备用；因故直流油泵启动时，若需长时间时间运行，应启动高压备用密封油泵，将空侧油倒至高压备用油源，停直流油泵。
⑷停机情况下，若盘车结束，主机交流油泵一般就停用，密封油系统独立运行，应注意防止密封油系统缺油。（BOP停运，密封油运行时，要防止其缺油）
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| Most American families like to have a holiday__1__summer. Summer is season(季节) __2__holidays. It is very hot during the months of July and August. Children do not go to school during these __3__months. Some __4__like to stay at home during the holiday. They work in the garden, visit friends, __5__books, or __6__TV. Many families __7__their lunch to a park or somewhere far __8__the city. They like to eat where there are many trees or there is a nice lake. If they live near the sea, they often go to the beach. They can fish , swim or enjoy the sun there. America is a large country. Many families travel by ___9__or by train to see interesting places. They also travel by plane to a foreign country. Many big cities have many famous buildings, theatres, shops and other places__10__traveleres. | |||
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