问题 问答题 简答题

电流互感器二次侧的接地有什么规定?

答案

参考答案:

对于高压电流互感器,其次级绕组应有一点接地。这样,当初、次级绕组间因绝缘破坏而被高压击穿时,则可将高压引入大地,使次级绕组保持地电位,从而确保人身和二次电气设备的安全。应当注意的是,电流互感器二次回路只许一点接地而不应再有接地点,若发生两点接地则可能引起分流,使电气测量的误差增大或者影响继电保护装置的正确动作。

单项选择题
单项选择题

Analysts have their go at humor, and I have read some of this interpretative literature, (1) without being greatly instructed. Humor can be (2) , (3) a frog can, but the thing dies in the process and the innards are (4) to any but the pure scientific mind.

One of the things (5) said about humorists is that they are really very sad ’people clowns with a breaking heart. There is some truth in it, but it is badly (6) . It would be more (7) , I think, to say that there is a deep vein of melancholy running through everyone’s life and that the humorist, perhaps more (8) of it than some others, compensates for it actively and (9) Humorists fatten on troubles. They have always made trouble (10) They struggle along with a good will and endure pain (11) , knowing how well it will (12) them in the sweet by and by. You find them wrestling with foreign languages, fighting folding ironing hoards and’ swollen drainpipes, suffering the terrible (13) of tight boots. They pour out their sorrows profitably, in a (14) of what is not quite fiction nor quite fact either. Beneath the sparking surface of these dilemmas flows the p (15) of human woe.

Practically everyone is a manic depressive of sorts, with his up moments and his down moments, and you certainly don’t have to be a humorist to (16) the sadness of situation and mood. But there is often a rather fine line between laughing and crying, and if a humorous piece of writing brings a person to the point (17) his emotional responses are untrustworthy and seem likely to break over into the opposite realm, it is (18) humor, like poetry, has an extra content, it plays (19) to the big hot fire which is Truth, and sometimes the reader feels the (20) .

18()

A.when

B.that

C.whatever

D.because