【单选题】
电磁式仪表的精确度较低、刻度不均匀、容易受外磁场干扰,___。
A. 过载能力强
B. 测量直流电
C. 测量交流电
D. 以上都是
查看试卷,进入试卷练习
微信扫一扫,开始刷题
答案
D
解析
暂无解析
相关试题
【单选题】
使用前和使用完毕时安全用具都应___收好。
A. 用水冲洗
B. 收到工具库内
C. 放在比较隐蔽的地方
D. 擦拭干净
【单选题】
用钳形电流表测量三相平衡负载电流时,钳口中放入三根导线时的指示值___。
A. 为0
B. 一相电流值
C. 两相电流值之和
D. 两相电流值之差
【单选题】
避雷器主要用来保护___。
A. 建筑物
B. 构筑物
C. 电力设备
D. 电力线路
【单选题】
电气设备___的发热是允许的。
A. 过负荷
B. 过电压
C. 过电流
D. 按规定条件
【单选题】
10kV及以下的电力电缆、控制电力电缆、直埋时相互接近和交叉的最小允许距离___mm。
A. 100
B. 200
C. 250
D. 500
【单选题】
在爆炸危险场所,___V电压所产生的微弱火花即可能引起爆炸。
A. 6
B. 12
C. 110
D. 220
【单选题】
四极三相异步电动机的同步转速___rmin。
A. 300
B. 1500
C. 1000
D. 750
【单选题】
对于配电干线和接向固定设备的配电线路,故障持续时间不得超过___s。
A. 5
B. 4
C. 2
D. 1
【单选题】
容量在___kW以下的三相异步电动机一般均可以采用直接启动。
A. 4
B. 5
C. 6
D. 7
【单选题】
只要热继电器的整定值调节恰当,就可以使电动机在温度超过___之前停止运转。
A. 最大值
B. 允许值
C. 额定值
【单选题】
为了改善电动机的启动及运行性能,笼形异步电动机转子铁芯一般都采用___结构。
A. 直槽
B. 斜槽
C. 双槽
D. 涤槽
【单选题】
10KV级高压验电器的试验周期为___。
A. 两年
B. 一年
C. 六个月
D. 三个月
【单选题】
当系统接地电阻不超过4Ω时,每处重复接地电阻不得超过___Ω。
A. 1
B. 2
C. 10
D. 30
【单选题】
在线电压0.4kV的配电网中,中性线对地电压一般不超过___V。
A. 10
B. 25
C. 50
D. 大于50
【单选题】
当交流电频率增加时,人体的感知电流___。
A. 相应增加
B. 相应减小
C. 不确定
D. 不变
【单选题】
下列___不属于高压基本绝缘安全用具。
A. 绝缘棒
B. 绝缘夹钳
C. 绝缘靴,绝缘手套
D. 高压验电器
【单选题】
正弦交流电的三要素是、___角频率、初相位。
A. 瞬时值
B. 有效值
C. 额定值
D. 幅值
【单选题】
低压操作中,人体或其所携带的工具与带电体之间的距离应不小于___m。
A. 0.1
B. 0.5
C. 0.7
D. 大于0.7
【单选题】
接闪杆采用镀锌圆钢时,圆钢直径不应小于___mm。
A. 8
B. 10
C. 12
D. 16
【单选题】
凡有较大危险的环境里的局部照明灯应采用___V或24V安全电压供电。
A. 36
B. 24
C. 12
D. 6
【单选题】
一般情况下220V工频电压作用下人体的电阻为___Ω。
A. 1000
B. 1000~2000
C. 2000~2500
D. 2500以上
【单选题】
新装和大修后的低压线路和设备,要求绝缘电阻不低于___MΩ。
A. 0.2
B. 0.4
C. 0.5
D. 1
【单选题】
TN-C系统的PEN线断开后,则负载中性点将发生___。
A. 接地
B. 断“相”
C. 短路
D. 电移位
【单选题】
登杆前,应先将踏板挂钩挂好,踏板离地面___cm。
A. 5~10
B. 10~15
C. 15~20
D. 20~25
【单选题】
10kV及以下架空导线为铝绞线时,通过非居民区,其最小截面应为___mm2。
A. 10
B. 16
C. 25
D. 35
【单选题】
10kV及以下架空电力线路不应超过设计档距的___。
A. 0.01
B. 0.02
C. 0.03
D. 0.04
【单选题】
为了防止停电设备突然来电和邻近高压带电设备对停电所产生的___对人体的危害,需要用携带型接地线将停电设备已停电的三相电源短路并接地。
A. 感应电压
B. 残余电荷
C. 感应电流
D. 接触电压
【单选题】
剩余电流动作保护装置的选择,必须考虑用电设备和电路正常___的影响。
A. 剩余电流
B. 泄漏电流
C. 额定电流
D. 启动电流
【单选题】
带电部分与可接触及导体之间的绝缘电阻I类电气设备不低于___MΩ。
A. 0.5
B. 1
C. 2
D. 7
【单选题】
当采用___类灯具时,灯具外露可导电部分应可靠接地。
A. Ⅳ
B. Ⅲ
C. Ⅱ
D. Ⅰ
【单选题】
采用星三角降压启动时,启动电流为直接采用三角形联接时启动电流的___。
A. 1/3
B. 1/√3
C. 1/2
D. 1/√2
【单选题】
配电装置的长度超过6m时,屏后应有两个通向本室或其他房间的出口,其距离不宜大于___m。
A. 20
B. 15
C. 12
D. 10
【单选题】
操作后应检查各相的实际位置,无法___实际位置时,可通过间接方式确认设备已操作到位。
A. 知道
B. 判断
C. 观察
D. 猜测
【单选题】
低压配电线路其档距不一定超过___m。
A. 40
B. 30
C. 25
D. 20
【单选题】
室内灯具灯头使用的导线最小截面积,铜线不得小于___mm2,铝线不得小于1.5mm2。
A. 0.5
B. 0.75
C. 1
D. 1.5
【单选题】
三相电度表应按___相序接线。
A. 正
B. 负
C. 零
D. 递
【单选题】
电气设备停电后,即使是事故停电,在未拉开隔离开关和做好安全措施以前,不得___,以防突然来电。
A. 触及设备
B. 进入遮拦
C. 更改操作票
D. 触及设备和进入遮拦
【单选题】
兆欧表手摇发电机有离心式调速装置,转动发电机时使发电机能以___的速度转动。
A. 很快
B. 很慢
C. 先慢后快
D. 恒定
【单选题】
在相同的线电压下,负载作三角形连接时的有功功率是星形连接时有功功率的___倍。
A. 1
B. 2
C. 3
D. 1√3
【单选题】
无论高压设备带电与否,值班人员___单独移开或越过遮拦进行工作。
A. 不得
B. 可以
C. 有条件允许
D. 在这栏外进行这栏内的工作
推荐试题
【单选题】
When will vSphere Data Protection delete the expired backup image of a Platform Service Controller?___
A. Immediately after the retention period has expired.
B. After the expired backup image is restored.
C. During the next backup window following expiry.
D. During the next maintenance window following expiry.
【单选题】
Group A has permission to download files in Content Library. Group B does not have permission to download files in Content Library. If a user is a member of both groups, what will be the result?___
A. The user cannot download file from Content Library.
B. The user can download file from Content Library.
C. The user cannot access Content Library.
D. The user can access Content Library.
【单选题】
An administrator is trying to set up Host Partial Failure Response, but the Automated option is grayed out. What can the administrator change to enable the Automated option?___
A. Change the vSphere DRS Automation level to Partially Automated.
B. Change the vSphere DRS Automation level to Fully Automated.
C. Enable vSphere HA Host Monitoring.
D. Change the vSphere DPM Automation level to Automatic.
【单选题】
When you attempt to open a virtual machine console from the vSphere Web Client, the console does not connect. The following error message appears:<HTTP ERROR 404> <Problem accessin/.Reason: Not Found>. Why did not connect?___
A. Port 443 is in use.
B. Port 9443 is in use.
C. Port 8443 is in use.
D. Port 22443 is in use.
【单选题】
What new feature was introduced to the Content Library in vSphere 6.5?___
A. Mount an ISO directly from the Content Library.
B. Deploy a virtual machine from an OVF Package in a Content Library.
C. Upload a File from a URL to a Library Item.
D. Upload a File from a Local System to a Library Item.
【单选题】
How can an administrator exclude Encryption rights from a support engineer?___
A. Clone the role Virtual machine power user, remove Cryptographic operations privileges.
B. Clone the role Administrator and assign to the support engineer.
C. Clone the role Virtual machine power user and assign to the support engineer.
D. Clone the role No cryptography administrator and select privileges only for the support engineer.
【单选题】
The administrator must back up a vCenter HA deployment. Which component must be backed up?___
A. Passive node
B. Witness node
C. External database
D. Active node
【单选题】
What is the supported protocol to perform remote L3 traffic monitoring in vSphere 6.5?___
A. VXLAN
B. ERSPAN
C. RSPAN
D. SPAN
【单选题】
What are the minimum hardware requirements for a Windows vCenter Server with embedded PSC that manages a “Small” environment?___
A. 2vCPUs, 16 GB RAM
B. 4 vCPUs, 16 GB RAM
C. 2 vCPUs, 10 GB RAM
D. 4 vCPUs, 10 GB RAM
【单选题】
Which port is used for communication between ESXi and vSphere Data protection?___
A. 80
B. 443
C. 902
D. 22
【单选题】
What can prevent Storage DRS from functioning on a datastore?___
A. The datastore is configured for Virtual Machine Swapfile location.
B. The datastore is shared across multiple datacenters.
C. The datastore is connected to a host that is running Storage I/O Control.
D. Storage DRS advanced option IgnoreAffinityRulesForMaintenance is set to 1.
【单选题】
When troubleshooting VMware vCenter Server issues, when logging level provides maximum detail?___
A. Verbose
B. Trivia
C. Info
D. Error
【单选题】
What new feature is introduced in NFS 4.1 on ESXi 6.5?___
A. IPv6
B. KRB5i
C. AUTH_SYS
D. Storage DRS
【单选题】
What configuration option would ensure that a virtual NUMA topology is defined on VMs having more than eight virtual CPUs?___
A. cupid.coresPerSocket
B. numa.vcpu.followcorespersocket
C. numa.vcpu.maxPerVirtualNode
D. numa.vcpu.min
【单选题】
What is the minimum disk space required to deploy vSphere Data Protection (VDP) with 8 TB configuration?___
A. 4 TB
B. 16 TB
C. 8 TB
D. 12 TB
【单选题】
What advanced option for vSphere HA defines a maximum number of reset attempts by VMCP for a virtual machine?___
A. das.maxterminates
B. das.isolationshutdowntimeout
C. das.maxresets
D. fdm.isolationpolicydelaysec
【单选题】
What vSphere technology enables the administrator to ensure consistent configuration at scale?___
A. PowerCLI
B. Host Profiles
C. esxcli
D. vSphere Web Client
【单选题】
Which port is used for vSphere HA agent-to-agent communication?___
A. 443
B. 8182
C. 22
D. 902
【单选题】
Which log file would assist in identifying an issue that occurred during the database export phase of a vCenter Server upgrade process?___
A. vcdb_import.out
B. export.json
C. export-upgrade-runner.log
D. vcdb_export.out
【单选题】
Bidirectional CHAP is support by which storage initiator?___
A. software FCoE HBA
B. Fibre Channel HBA
C. independent hardware iSCSI HBA
D. dependent hardware iSCSI HBA
【单选题】
What is a pool of raw storage capacity that a storage system can provide to Virtual Volumes?___
A. protocol endpoint
B. storage container
C. storage provider
D. datastore
【单选题】
vSphere 6.5 DRS is now Network-Aware. Based on network utilization, when will DRS balance VMs?___
A. DRS will balance VMs when a network resource pool is configured for VMs.
B. DRS will balance VMs when Network I/O Control is enabled.
C. DRS will place VMs on initial boot for hosts that have network utilization lower that the threshold.
D. DRS will vMotion VMs when network utilization is higher than the threshold on a particular host.
【单选题】
A scripted upgrade of ESXi fails due to an incorrect parameter in the upgrade script. What file must the administrator modify to correct the problem?___
A. vmreconfig.pl
B. hostinfo.pl
C. ks.cfg
D. boot.cfg
【单选题】
A VM folder contains VM1 and VM2. Group A has permission to power on virtual machines, defined on the VM folder and its children. Group B has permission to power off virtual machine VM2. If a user is a member of group A and B, what action can the user perform?___
A. Suspend VM2.
B. Power off VM1.
C. Power on and power off VM1.
D. Power on and power off VM2.
【单选题】
The networking team has requested to have a dedicated network for iSCSI traffic. This task has been assigned to the vSphere Administrator. What is the VMware-recommended way to accomplish this?___
A. Configure Static Routes on each ESXi Server.
B. Configure the right subnet.
C. Create a custom IP Stack.
D. Define a dedicated gateway for the iSCSI vmkernel.
【单选题】
To prevent possible failures or issues during a vSphere upgrade, which component should be upgraded first?___
A. ESXi Hosts
B. virtual machines
C. datastores
D. vCenter Server
【单选题】
What is the command for updating an ESXi host?___
A. esxcli software vib update –d /vmfs/volumes/Datastore/DirectoryName/PatchName.zip
B. esxupdate software update –d”/vmfs/volumes/Datastore/DirectoryName/PatchName.zip”
C. esxcli software update –d “/vmfs/volumes/Datastore/DirectoryName/PatchName.zip”
D. esxupdate software vib update –d /vmfs/volumes/Datastore/DirectoryName/PatchName.zip
【单选题】
A vSphere Administrator would like to identify which physical NUMA node their virtual machine is currently residing on. What esxtop metric would provide this information?___
A. GST_ND[x]
B. OVD_ND[x]
C. NRMEM
D. NHN
【单选题】
How can a vSphere administrator ensure that two virtual machines never run on the same datastore in a datastore cluster, while permitting the VMs to be load-balanced?___
A. Use an Intra-VM Anti-Affinity Rule.
B. Configure a storage DRS VM override.
C. Disable storage
D. RS for the VMs.
【单选题】
What is the VMware-recommended way to move a physical adapter out of Network I/O Control’s scope?___
A. Set the teaming policy to “Route Based on Physical NIC Load.”
B. Add the vmnic to the Net.NetNiocAllowOverCommit parameter in Advanced System Settings.
C. Add the vmnic to the Net.IOControlPnicOptOut parameter in Advanced System Settings.
D. Move the vmnic to a different vmUplink port on the Distributed Switch.
【单选题】
A VM folder contains VM1 and VM2. Group A has permission to power on virtual machines, defined on the VM folder and its children. Group B has permission to power off virtual machines, defined on the VM folder and its children. If a user is a member of Groups A and B, what will be the user’s effective permission on VM1 and VM2?___
A. Power on
B. Power off.
C. Power on and Power off.
D. Reset.
【单选题】
Group 1 is granted console interaction on a VM folder. User 1 is granted no console interaction on the same VM folder. What will be the outcome if User 1 tries to access the console of a virtual machine?___
A. User 1 will not be able to access the virtual machines in the VM folder.
B. User 1 will not have access to the virtual machine console.
C. User 1 will have access to the virtual machine console.
D. User 1 will have console access only via the vSphere Web Client.
【单选题】
Which statement is true regarding the use of VMFS3 datastores with vSphere 6.5?___
A. VMFS3 datastores can be used but not created.
B. VMFS3 datastores can be neither used nor created.
C. VMFS3 datastores will be present but unmounted.
D. VMFS3 datastores can be created and used.
【单选题】
In the Exhibit, each VM has a 1GHz non-expandable reservation. If all VMs are powered on in sequence, what would be the outcome?___
A. VM4 cannot be powered on.
B. VM5 cannot be powered on.
C. VM6 cannot be powered on.
D. VM3 cannot be powered on.
【单选题】
vSphere 6.5 introduced MAClearning capabilities for VMware’s virtual switches. What three benefits will it provide? (Choose three.)___
A. Reduced memory consumption.
B. Reduced consumption of extra CPU cycles.
C. Increased network throughput.
D. Prevent packet flooding inside the vSwitch.
【单选题】
What is the default pathing policy for most active-active arrays?___
A. Fixed
B. Most Recently Used
C. Dynamic
D. isk Morroring
【单选题】
Which command will show the iSCSI sessions on a ESXi 6.5 host?___
A. esxcli storage iscsi session get
B. esxcli iscsi session get
C. esxcli storage iscsi session
D. esxcli iscsi session list
【单选题】
Which of the following is not a parameter for traffic filtering or marking?___
A. virtual port ID
B. Protocol
C. Traffic Direction
D. DSCP value
E. Traffic redirection
【单选题】
A vSphere administrator wants to enable a virtual machine with Secure Boot, but in VM setting, Secure Boot option was not found under Boot Options. What could be the cause?___
A. The virtual hardware is not compatible.
B. The virtual machine has missing drivers.
C. The virtual machine OS does not support secure boot.
D. VMware Tools is not upgraded.
【单选题】
A virtual machine is connected on a distributed port group where the average bandwidth configured in the traffic shaping policy is 100 Mbps. The VM network adapter is configured with a reservation of 200 Mbps. What is the VM’s effective bandwidth?___
A. 200 Mbps
B. 100 Mbps
C. 150 Mbps
D. 400 Mbps