【单选题】
时间继电器的延时动合接点是指继电器通足够大的电时瞬时闭合的接点。___
A. 对
B. 错
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答案
B
解析
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电工作业人员应根据实际情况遵守有关安全法规,规程和制度。___
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人体过分接近带电体,其间距小于放电距离时,会直接产生强烈的电弧对人放电,造成人触电伤亡。___
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工作票是准许在电气设备上工作的书面命令,是执行保证安全技术措施的书面依据,一般有三种格式。___
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电压互感器二次侧不能开路,否则绕组将被烧毁。___
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互感器分电压互感器和电流互感器两大类,它们是供电系统中测量保护操作用的重要设备。___
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万用表测量电压时是通过改变并联附加电阻的阻值来改变测量不同电压的量程。___
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通过与磁场方向平行的某一面积上的磁力线总线,称为通过该面积的磁通。___
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三相交流对称电路中,如采用星形接线时,线电压等于相电压。___
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断路器的关合电流是指保证断路器可靠关合而又不会发生触头熔焊或其它损伤时,断路器允许通过的___。
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【单选题】
当变压器负载一定(即损耗不变),而周围环境温度不同时,变压器的实际温度就___。
A. 恒定
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【单选题】
用数字万用表的直流电压档测量直流电压时极性接反,则___。
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电路处于断路状态时,电路中没有___流过。
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避雷线在防雷保护中所起的作用是___。
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变配电所运行管理实行___制度。
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【单选题】
在变电站外线路工作,一经合闸即可送电到施工线路的线路开关和刀闸操作手柄上应悬挂___标示牌。
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C. 在此工作
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六氟化硫(SF6)气体化学性能稳定,所以与水或其它杂质成分混合后,在电弧的作用下也不会产生有腐蚀性的低氟化合物。___
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【单选题】
六氟化硫(SF6)负荷开关一般不设置气吹灭弧装置,所以它的灭弧能力比六氟化硫(SF6)断路器强。___
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接地系统的单相触电比不接地系统的单相触电危险性大。___
A. 对
B. 错
【单选题】
重复接地的接地电阻要求小于4Ω。___
A. 对
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【单选题】
接触电压触电是由于电气设备绝缘损坏发生漏电,造成设备金属外壳带电并与地之间出现对地电压引起的触电。___
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当变压器的温度达到稳定时的温升时称为稳定温升。___
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A. 对
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线路装设自动重合装置后,对提高供电可靠性起很大作用。___
A. 对
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正常情况下,第一种操作票应在工作的当天交给值班员。___
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只有在同一停电系统的所有工作结束,工作票全部终结收回,拆除所有接地线临时遮栏和标示牌,恢复常设遮栏并得到运行值班调度人员许可命令,方可合闸送电。___
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高分断能力高压熔断器的特点之一是分断___的能力强。
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真空灭弧室的绝缘外壳采用玻璃制作时主要缺点是___。
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___是用来防止工作人员直接接触触电的安全用具。
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绝缘安全用具分为___。
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___的绝缘强度不能承受电气设备或线路的工作电压,只能起加强基本安全用具的保护作用。
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在电阻并联的电路中,电路的电流等于___。
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在电阻并联的电路中,电路的电流等于___。
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以下过电压中___属于内部过电压。
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在全部停电和部分停电的电气设备上工作时,必须完成的技术措施有:___验电挂接地线装设遮栏和悬挂标示牌。
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触头断开后,触头之间如果电弧已熄灭,则电路实际上没有被切断。___
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推荐试题
【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?___
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【多选题】
What are two reasons why a datastore in a Storage DRS cluster cannot enter maintenance mode?(Choose two.)___
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D. RS is disabled on the virtual disk.
【多选题】
What two methods are used to configure VMware vSphere Storage I/O Control shares and limits? (Choose two.)___
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【多选题】
ESXi 6.5 introduces VMFS6, which supports both 512e and 512n devices. What three configurations are supported when using these devices? (Choose three.) ___
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D. Storage DRS clusters containing only both 512e and 512n devices.
【多选题】
A vSphere Administrator observes that the Primary VM configured with Fault Tolerance is executing slowly. After further investigation, it is determined that the Secondary VM is on an overcommitted ESXi host. What two methods will correct the problem? (Choose two.)___
A. Use Storage vMotion to migrate the Secondary VM to another datastore.
B. Use vMotion to migrate the Secondary VM to a different ESXi host.
C. Configure a CPU limit on the Primary VM which will also apply to the Secondary VM.
D. Turn off and turn on FT in order to recreate the Secondary VM on a different datastore.
【多选题】
Which two features require the use of Host Profiles? (Choose two.)___
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【多选题】
What three processes on the vCenter Server Appliance (VCSA) does“vmware-watchdog monitor? (Choose three.) ___
A. vmware-eam
B. vmcad
C. vmware-vpostgres
D. vpxd
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【多选题】
What three processes on the vCenter Server Appliance (VCSA) does“vmware-watchdog monitor? (Choose three.) ___
A. vmware-eam
B. vmcad
C. vmware-vpostgres
D. vpxd
E. vsan-health
【多选题】
Which two statements correctly describe VM-Host affinity rules? (Choose two.) ___
A. When there is more than one VM-Host affinity rule in a vSphere DRS cluster, the rules are applied equally.
B. After creating a VM-Host affinity rule, its ability to function in relation to other rules is predetermined.
C. When there is more than one VM-Host affinity rule in a vSphere
D. RS cluster, the rules will be ranked.
【多选题】
An administrator wants to enable proactive HA by moving virtual machines automatically if a hardware alert is triggered. What are the three required settings? (Choose three.)___
A. Set vSphere DRS Automation to Partially Automated.
B. Turn on Proactive HA.
C. Set the Proactive HA Automation Level to Manual.
D. Set the Proactive HA Automation Level to Automated.
E. Turn on vSphere HA and vSphere DRS.
【多选题】
If vCenter Server 5.5 installation has one or more services deployed remotely, which three services are relocated to vCenter Server 6.5 on upgrade? (Choose three.)___
A. vCenter Inventory Services
B. vSphere Authentication Proxy
C. vSphere Web Client
D. vSphere
E. SXi Dump Collector
【多选题】
What two debugging levels can a virtual machine be configured to? (Choose two.)___
A. Verbose
B. Debugging
C. Statistics
D. Trivia
【多选题】
What are three benefits of using a few large-capacity LUNs instead of many small-capacity LUNs? (Choose three.) ___
A. Better performance because there is less contention for a single volume.
B. More flexibility for resizing virtual disks.
C. Less wasted storage space.
D. More flexibility to create virtual machines without adding new LUNs.
E. Fewer VMFS datastores to manage.
【多选题】
Which two configurable options are available in Boot Options for a virtual machine? (Choose two.)___
A. Tools Upgrades
B. Encryption
C. Firmware
D. Force BIOS setup
【多选题】
Which three VMware-recommended best practices should an administrator follow before upgrading to vSphere 6.5? (Choose three.)___
A. Disconnect ESXi host from vCenter.
B. VMware Tools are installed in the virtual machine.
C. Ensure that the system hardware complies with ESXi requirements.
D. Back up the host.
E. Check the interoperability of any other software integrated with vSphere.
【多选题】
What are two requirements to enable EVC in vSphere DRS cluster? (Choose two.)___
A. CPUs must be from the same vendor.
B. EVC must use the lowest possible baseline supported by the hardware.
C. CPUs must be in the same family and of the same speed.
D. No VMs may be running in the cluster.
【多选题】
What three conditions could result in VMware Flash Read Cache being unable to claim a disk? (Choose three.)___
A. The disk is not listed in the VMware hardware compatibility guide.
B. The disk is not detected as an SSD.
C. The disk is not detected as local.
D. The disk is in use by VMFs.
【多选题】
Boot from SAN is supported on which three storage technologies? (Choose three.)___
A. VMware vSAN
B. FCoE
C. NFS 4.1
D. iSCSI
E. FC
【多选题】
Which two components are part of storage I/O multipathing on ESXi? (Choose two.)___
A. SATP
B. VASA
C. PSP
D. VAAI
【多选题】
Which two statements are true about Highly Available vSphere Auto Deploy infrastructure? (Choose two.)___
A. It helps prevent data loss.
B. It is a prerequisite for using vSphere Auto Deploy with stateful install.
C. It requires two or more Auto
D. eploy servers.
【多选题】
The virtual machine log rotation size can be changed for all VMs by which two interfaces? (Choose two.)___
A. PowerCLI
B. vSphere Web Client
C. ESXi host client
D. esxcli
【多选题】
Which two configuration options can exclude virtual disks from snapshot operations? (Choose two.)___
A. Use RDM in virtual mode for virtual disk.
B. Use virtual disks in Independent – Persistent mode.
C. Use a virtual disk larger than 2 TB in size.
D. Use RDM in physical mode for virtual disk.
【多选题】
Which two storage configurations on the source server are unsupported with VMware Converter? (Choose two.)___
A. Linux LVM
B. software RAID
C. GPT/MBR hybrid disks
D. Windows basic volumes
E. Windows dynamic volumes
【多选题】
Which two statements about vCenter HA are correct? (Choose two.)___
A. ESXi 5.5 or later is required.
B. vCenter HA network latency between nodes must be less than 50 ms.
C. NFS datastore is supported.
D. It must be deployed on a 3
E. SXi host cluster with DRS enabled.
【多选题】
An attempt to delete NFS datastore from a ESXi host returns the error: Sysinfo error on operation returned the following status:< Busy> Which two statements could explain this failure? (Choose two.)___
A. NFS datastore is a part of Storage DRS Cluster.
B. NFS.VolumeRemountFrequency value is set to 30.
C. Storage I/O Control is enabled on NFS datastore.
D. NFS datastore has running or registered virtual machines.
【多选题】
An administrator finds that the Microsoft Exchange virtual machines are exhibiting network latency. What two in-guest changes can help decrease latency? (Choose two.)___
A. LRO
B. TSO
C. SR-IOV
D. PVRDMA
【多选题】
Which two types of iSCSI adapters require VMkernel networking configuration? (Choose two.)___
A. dependent hardware
B. in-guest
C. software
D. independent hardware
【多选题】
Which two statements are true for NFS v4.1 firewall behavior? (Choose two.)___
A. It closes port 2049.
B. It sets allowed. All flag to TRUE.
C. It sets allowed. All flag to FALSE.
D. It opens port 2049.
【多选题】
A vSphere Administrator attempts to enable Fault Tolerance for a virtual machine but receives the following error: Secondary VM could not be powered on as there are no compatible hosts that can accommodate it. What two options could cause this error? (Choose two.)___
A. The other ESXi host(s) are in Maintenance Mode.
B. Hardware virtualization is not enabled on the other ESXi host(s).
C. The other ESXi host(s) are in Quarantine Mode.
D. Hardware MMU is enabled on the other
E. SXi host(s).
【多选题】
Storage capabilities be populated in what two ways? (Choose two.)___
A. The administrator can use tags to describe capabilities.
B. Default capabilities are provided by vCenter Server.
C. Datastores can advertise their capabilities through VAAI.
D. Datastores can advertise their capabilities through VASA.
【多选题】
In network troubleshooting it is important to know what upstream switch the ESXi host is connected to. Which two features does ESXi provide to help identify the upstream switch? (Choose two.)___
A. Promiscuous mode
B. DPM
C. LLDP
D. CDP
【多选题】
Virtual Volumes supports which three VMware features? (Choose three.)___
A. Instant Clones
B. Distributed Resource Scheduler
C. Linked Clones
D. vMotion
E. Storage Distributed Resource Scheduler
【多选题】
vSphere DRS helps to balance virtual machines with available resources in a vSphere cluster. What three types of resources can be taken into account for balancing? (Choose three.)___
A. CPU
B. physical NIC saturation of an ESXi host
C. virtual NIC saturation of a virtual machine
D. RAM
E. storage latency
【多选题】
Which three design requirements must be satisfied to enable RAID-6 objects in a VMware vSAN cluster? (Choose three.)___
A. vSAN Advanced license or higher
B. vSAN stretched cluster
C. at least six hosts contributing storage
D. deduplication and compression
E. all flash configuration
【多选题】
When using "Cluster resource percentage" for host failover capacity in vSphere HA Admission Control, the total resource requirements are calculated from which two values? (Choose two.)___
A. Total vCPUs assigned to each VM.
B. Average CPU usage on each VM over time.
C. Memory reservations on each VM.
D. Total memory assigned to each VM.
E. Average active memory on each VM over time.
F. CPU reservations on each VM.
【多选题】
Which are four attributes of the Active vCenter HA node? (Choose four)___
A. It uses the vCenter HA network to communicate with the Witness node.
B. It constantly replicates vPostgres data with the Witness node.
C. It uses a public IP address for the management interface.
D. It runs the active vCenter Server Appliance instance.
E. It uses the vCenter HA network for replication of data to the Passive node.
F. It provides a quorum to protect against split-brain situations.
【多选题】
Which are two vCenter Server two-factor authentication methods? (Choose two.)___
A. RSA SecurID
B. Smart Card
C. SAML
D. Symantec VIP
【多选题】
An administrator is creating VMkernel adapters on an ESXi 6.5 host and wants to create separate VMkernel adapters for every type of traffic in the default TCP/IP stack. Which three types of traffic can be explicitly enabled on a separate VMkernel adapter? (Choose three.)___
A. Virtual SAN traffic
B. NFS traffic
C. vMotion traffic
D. vSphere HA traffic
E. Fault Tolerance logging traffic
【多选题】
When migrating a Windows vCenter Server 6.0 to the vCenter Server Appliance 6.5, which two will be migrated by default? (Choose two.)___
A. Local Windows OS users and groups
B. Configuration
C. Custom ports
D. FQDN
E. Historical and Performance data
【多选题】
Which three types of Content Libraries exist within vSphere 6.5? (Choose three.)___
A. Remote Content Library
B. Published Content Library
C. Local Content Library
D. Shared Content Library
E. Subscribed Content Library