The following scenario is to be used for questions 30, 31, and 32. Greg is the security facility officer of a financial institut

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问题 The following scenario is to be used for questions 30, 31, and 32.
Greg is the security facility officer of a financial institution. His boss has told him that visitors need a secondary screening before they are allowed into sensitive areas within the building. Greg has also been told by the network administrators that after the new HVAC system was installed throughout the facility, they have noticed that power voltage to the systems in the data center sags.
Which of the following best describes the situation that the network administrators are experiencing?

选项 A、Brownouts
B、Surges
C、In-rush current
D、Power line interference

答案C

解析 C正确。当某个重型电子设备被打开时,它会拉走大量的电流,这也叫启动电流。如果该设备抽取了足够多的电流,它就会对周围设备造成电力可用性的下降。这会对它们的性能产生负面影响。将数据处理中心和设备的电路线路段与其他设备的线路段区分开是个不错的主意,这样可以保证设备不会受到这些问题的影响。
A不正确。因为当电力公司承受的压力变大时,他们通常会降低电力网中的电压,这也叫暂时低压。稳压器可以用来调节电力的波动。稳压器使用不同范围内的电压,但是对设备仅会释放出期望的120伏的交流电。暂时低压通常与HVAC系统没有关联。
B不正确。因为电涌是指来自电源的电压有一个急速上升。电涌能非常快速地造成巨大的损害,它是最常见的电力问题之一,一般可以用电涌保护器来进行控制。这些电涌保护器通常使用一个叫做金属氧化物压敏电阻的设备,在电涌出现时将多余的电压移到地面。
D不正确。因为如果提供的是干净电力,则说明电力供应不包含任何干扰或电压波动。可能出现的干扰(线路噪音)类型是电磁干扰(EMI)和射频干扰(RFI)。这些都是当电流穿过电线时,对电流的干扰。这个问题并没有解决类似这样的干扰问题。
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