【单选题】
一合大功率电动机，变频器调速运行在低速段时电动机过热。此故障的原因可能是___。
A. 电动机参数设置不正确
B. U/f比设置不正确
C. 电动机功率小
D. 低速时电动机自身散热不能满足要求
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相关试题
【单选题】
变频器轻载低频运行，启动时过电流报警。此故障的原因可能是___。
A. U/f比设置过高
B. 电动机故障
C. 电动机参数设置不当
D. 电动机容量小
【单选题】
变频调速时，电动机出现过热，___的方法不能改进过热问题。
A. 尽可能不要低频运行
B. 换用变频电动机
C. 改进散热条件
D. 提高电源电压
【单选题】
教启动器启动完成后，旁路接触器刚动作就跳用。故障原因可能是___。
A. 启动参数不适合
B. 晶闸管模块故障
C. 启动控制方式不当
D. 旁路接触器与软启动器的接线相序不一致
【单选题】
软启动器进行启动操作后，电动机运转，但长时间达不到额定值。此故障原因不可能是___。
A. 启动参数不合适
B. 启动线路接线错误
C. 启动控制方式不当
D. 品闸管模块故障
【单选题】
教启动器启动完成后，旁路接触器刚动作就跳闸。故障原因可能是___。
A. 启动电流过大
B. 旁路接触器接线相序不对
C. 启动转矩过大
D. 电动机过载
【单选题】
电网电压正常情况下，启动过程中软启动器“欠电压保护”动作。此故障原因不可能是___。
A. “欠电压保护”动作整定值设定不正确
B. 减轻电流限幅值
C. 电压取样电路故障
D. 晶闸管模块故障
【单选题】
软启动器接通主电源后，虽处于待机状态，但电动机有嗡嗡响。此故障不可能的原因是___。
A. 晶闸管短路故障
B. 旁路接触器有触点粘连
C. 触发电路故障
D. 启动线路接线错误
【单选题】
软启动器采用内三角接法时，电动机额定电流应按相电流设置，这时___。
A. 容量提高、有三次谐波
B. 容量提高、无三次谐波
C. 容量不变、有三次谐波
D. 容量减少、无三次谐波
【判断题】
从业人员在职业活动中，要求做到仪表端庄、语言规范、举止得体、待人热情
【判断题】
市场经济条件下，是否遵守承诺，并不违反职业道德规范中关于诚实守信的要求
【判断题】
勤劳节俭虽然有利于节省资源，但不能促进企业的发展
【判断题】
爱岗敬业作为职业道德的内在要求，指的是员工只需要热爱自己特别喜欢的工作岗位
【判断题】
领导亲自安排的工作一定要认真负责，其他工作可以马虎一点
【判断题】
电压是产生电流的根本原因，因此电路中有电压必有电流
【判断题】
稳压是在电网波动及负载变化时保证负载上电压稳定
【判断题】
感应电流产生的磁通总是阻碍原磁通的变化
【判断题】
变压器的器身主要由铁芯和绕组这两部分所组成
【判断题】
三相异步电动机的转子由铁芯、转子绕组、风扇、换向器等组成
【判断题】
三相异步电动机工作时，其转子的转速不等于旋转磁场的转速
【判断题】
低压电器的符号在不同的省市有不同的标准
【判断题】
三极管符号中的箭头表示发射结导通时电流的方向
【判断题】
放大电路通常工作在小信号状态下，功放电路通常工作在极限状态下
【判断题】
负反馈是指反馈到输入端的信号与给定信号比较时，极性必须是负的
【判断题】
负反馈能改善放大电路的性能指标，但放大倍数并没有受到影响
【判断题】
射极输出器是典型的电压串联负反馈放大电路
【判断题】
单相整流是将交流电变为大小及方向均不变的直流电
【判断题】
电子电路常用电子毫伏表及示被器进行测试
【判断题】
电工在维修有故障的设备时，重要部件必须加倍爱护，而像螺钉螺帽等通用件可以随意放置
【判断题】
岗位的质量要求是每个领导干部都必须做到的最基本的岗位工作职责
【判断题】
电气线路测绘前先要了解测绘的对象，了解控制过程、布线规律、准备工具仪表等
【判断题】
电气线路测绘前要检验被测设备是否有电，无论什么情况都不能带电工作
【判断题】
测绘T68型管床电器位置图时，要面出2台电动机在机床中的具体位置
推荐试题
【单选题】
A vSphere Administrator wants to reserve 0.5 Gbps for virtual machines on each uplink on a disturbed switch that has 10 uplinks. What is the quota that should be reserved for the network resource pool?___
A. 10 Gbps
B. 5 Gbps
C. 100 Gbps
D. 0.5 Gbps
【单选题】
A vSphere administrator manages a cluster which includes critical and non-critical virtual machines. The cluster requires different permissions for contractors and non-contractors. How can the administrator exclude the contractor group from some of the critical VMs?___
A. Apply permission for both contractors and non-contractors on the cluster level.
B. Apply permission for both contractors and non-contractors on the cluster level. Remove permission on the critical VMs for contractors.
C. Remove permission for contractors on the cluster level. Apply permission on the critical VMs for noncontractors.
D. Apply permission for both contractors and non-contractors on the VMs. Remove permission on the critical VMs for contractors.
【单选题】
In an ESXi 6.5 cluster only "NFS datastore has running or registered virtual machines" returns. A vSphere HA cluster with four hosts has admission control configured to tolerate one host failure. Which statement is true if a fifth host is added?___
A. CPU and Memory capacity will be set to 50%.
B. CPU and Memory capacity will be set to 30%.
C. CPU and Memory capacity will be set to 25%.
D. CPU and Memory capacity will be set to 20%.
【单选题】
Which command can be run to troubleshoot connectivity problems with vmkernal network interfaces?___
A. esxcli network
B. vmkping
C. net-status
D. vicfg-vmknic
【单选题】
What counter should an administrator check to determine if a virtual machine is ballooning?___
A. swapinRate
B. vmmemctltarget
C. swapped
D. vmmemctl
【单选题】
By default, how often is the vCenter vpx user password automatically changed?___
A. 15 days
B. 60 days
C. 30 days
D. 45 days
【单选题】
Which metric in the Exhibit would identify high latency for a virtual machine operating system?___
A. QAVG/cmd
B. KAVG/cmd
C. DAVG/cmd
D. GAVG/cmd
【单选题】
What VM Monitoring setting would ensure that the failure interval for a virtual machine is defined as 120 seconds?___
A. High
B. Normal
C. Low
D. Medium
【单选题】
The business managers have asked the IT administrator to ensure configuration compliance in the vSphere infrastructure. The IT administrator wants to use Host Profiles to accomplish this, but is unable to do so. Why is the administrator unable to use Host Profiles?___
A. The infrastructure uses a vSphere Standard license.
B. The infrastructure has servers with various CPU families.
C. The user has only the “Administrator” role.
D. Host Profiles apply only to storage settings.
【单选题】
What is the result of a “Consolidate” action on a virtual machine?___
A. All snapshots on the virtual machines will be deleted.
B. The virtual machine will be reverted to its last snapshot.
C. Redundant delta disks will be combined and deleted.
D. A new snapshot with memory state will be created.
【单选题】
A Telco customer is implementing NFV using vSphere as the virtualization platform. Which feature can help achieve a high packet rate with lower CPU consumption?___
A. Network I/O Control
B. SplitRX
C. ERSPAN
D. LACP
【单选题】
What is the VMware-recommended best practice for Fibre Channel zoning?___
A. soft zoning
B. single-initiator-multiple-target zoning
C. single-initiator zoning
D. single-initiator-single-target zoning
【单选题】
How can a vSphere administrator ensure that a set of virtual machines run on different hosts in a DRS cluster?___
A. Use a VM-Host affinity rule.
B. Add the VMs to a vApp.
C. Use a VM-VM affinity rule.
D. Place the VMs in different folders.
【单选题】
vCenter Server Appliance Instance can be backed up using which Client Interface?___
A. vSphere Client Interface
B. vSphere Web Client Interface
C. VMware Host Client Interface
D. Virtual Appliance Management Interface
【单选题】
What tool can capture network traffic at the uplinks, or vSwitch, or virtual port levels?___
A. tcpdump-uw
B. wireshark
C. pktcap-uw
D. pcap
【单选题】
Which storage feature always requires the use of third-party software on ESXi?___
A. Hardware Acceleration for NAS devices
B. VVOL
C. Hardware Acceleration for Block
D. evices
【单选题】
An ESXi host's VMCA-Signed certificate has expired. How can the certificate be renewed?___
A. In the vSphere Web Client, browse to the host in question. Click the Manage tab and select settings. Select System and click Certificate, then click the Renew button.
B. In the vSphere Web Client, browse to the host in question. Click the Manage tab and select settings. Select System and click Certificate, then click the Refresh CA Certificates button.
C. Run the command /sbin/generate-certificates on the affected host.
D. Disconnect the host from vCenter Server and reconnect it.
【单选题】
Which is the correct order for upgrading vSphere components?___
A. vCenter Server, ESXi hosts, VMware Tools, Virtual Machine hardware
B. VMware Tools, Virtual Machine hardware, ESXi hosts, vCenter Server
C. vCenter Server, Virtual Machine hardware, VMware tools, ESXi hosts
D. ESXi hosts, vCenter Server, Virtual Machine hardware, VMware Tools
【单选题】
Which iSCSI initiator type can be used with any network interface card?___
A. Software iSCSI initiator
B. Software FCoE adapter
C. Hardware Independent iSCSI initiator
D. Hardware Dependent iSCSI initiator
【单选题】
An administrator is attempting to power on a virtual machine with 32GB of memory. The operation fails with the following error: <Could not power on VM: No space left on device> <Checking the space on the virtual machine's datastore, there is 30GB free.> Which action would allow the VM to power on?___
A. Set a 2GB memory reservation on the VM.
B. Mount the virtual disk from the affected VM on to another virtual machine and free up space from within the OS.
C. Enable vSphere HD admission control on the cluster in which the VM resides.
D. Set a 2GB memory limit on the VM.
【单选题】
An administrator attempts to manually reclaim space on thin-provisioned VMFS6 volumes but finds that no additional space is being recovered. Which could be causing this?___
A. vSphere 6.5 does not support manual UNMAP.
B. The manual UNMAP operation has been moved to the vSphere web client.
C. The VASA version is use is incompatible.
D. UNMAP is automated for VMFS6.
【单选题】
An administrator has upgraded to vSphere 6.5 and also wants to use Kerberos authentication for NFS. Which can be done to the existing NFSv3 volumes to enable this feature?___
A. Perform a storage rescan on VMFS volumes.
B. Unmount the NFSv3 datastore, and then mount as NFSv4.1 datastore.
C. Nothing. All NFSv3 mounted datastores are upgraded automatically during vSphere upgrades.
D. Perform a scan of new storage devices.
【单选题】
An administrator wants to restore the vCenter Server Appliance 6.5 from backup. Where can this be accomplished?___
A. from the ESXi Host Client
B. from the VMware vSphere Appliance Management Interface
C. from within the VMware vSphere Web Client
D. from the vCenter Server Appliance Installer
【单选题】
The administrator wants to power on VM-K2, which has a 2GHz CPU reservation. VM-M1, VM-M2, and VM-K1 are all powered on. VM-K2 is not powered on. The exhibit shows the parent and child resource reservations. If Resource Pool RP-KID is configured with an expandable reservation, which statement is true?___
A. VM-K2 will be unable to power on because there are insufficient resources.
B. VM-K2 will be able to power on since resource pool RP-KID has 2GHz available.
C. VM-K2 will be unable to power on because only 2GHz are reserved for RP-KID.
D. VM-K2 will receive resource priority and will be able to power on this scenario.
【单选题】
Which is the block size on the VMFS6 datastore?___
A. All small and large file blocks are 8MB.
B. All small and large file blocks are 1MB.
C. Small file blocks are 512KB. large file blocks are 64MB.
D. Small file blocks are 1MB, large file blocks are 512MB.
【单选题】
When installing vCenter Converter Standalone, why must an administrator perform a client-server installation instead of a local installation?___
A. to manage conversion tasks remotely
B. to convert virtual machines as well as physical machines
C. to allow installation of the Converter agent on remote source machines
D. to hot clone physical or virtual machines
【单选题】
Which is required by vCenter Converter Standalone to convert a physical Red Hat Enterprise Linux 7 machine to a virtual machine?___
A. The Linux machine must be powered off.
B. The Linux machine must have the SSH daemon started.
C. The Linux machine must use a static IP address.
D. The Linux machine must have a fully-qualified domain name.
【单选题】
An administrator is troubleshooting network communications between a vCenter Server and an ESXi 6.5 host. Which log shows the related events between these components?___
A. /var/log/fdm.log
B. /var/log/vpxa.log
C. /var/log/hostd.log
D. /var/log/auth.log
【单选题】
An administrator has recently upgraded from vSphere 6.0 to 6.5, and can no longer see the software iSCSI named vmhba33. Which could be the reason for this?___
A. The upgrade has changed the vmhba name.
B. vSphere 6.5 automates iSCSI configurations.
C. vSphere 6.5 no longer supports software iSCSI.
D. The upgrade has deleted the vmhba.
【单选题】
An administrator is trying to vMotion a VM from his datacenter to a recovery site. Which is the maximum allowed RTT (Round-Trip Time) latency between source and destination host?___
A. 100 milliseconds
B. 150 milliseconds
C. 15 milliseconds
D. 10 milliseconds
【单选题】
Which is required for configuring iSCSI Software Adapter network port binding?___
A. VMkernel of the iSCSI traffic must be load balanced using Route based on IP Hash algorithm.
B. VMkernel of the iSCSI traffic must be load balanced using Route based on Source Virtual Port ID algorithm.
C. VMkernel of the iSCSI traffic must be load balanced using Route based on Source MAC Hash algorithm.
D. VMkernel of the iSCSI traffic must be bound to only one active network adapter.
【单选题】
In vSphere Data Protection 6.1, which is the function of a Backup Verification job?___
A. None. Backup Verification job is not a feature of vSphere Data Protection
B. It is a manual task -Power it on -Verify the guest OS -Check started applications
C. It is an automatic process -Restore a virtual machine -Power it on -Verify that the guest OS is booted by communicating with the Backup Verification agent
D. It is an automatic process -Restore a virtual machine -Power it on -Verify that the guest OC is booted by detecting the VMware ToolsTM "heartbeats"
【单选题】
An administrator has enabled vSphere Distributed Switch Health Check. The hosts connected to that Distributed Switch all display an alert:< vSphere Distributed Switch MTU supported status > .The administrator has all of the VMkernel ports MTU sizes set to 1600. Which action will remedy this problem?___
A. Configure the Distributed Switch to MTU 9100.
B. Disconnect and reconnect the physical network cable.
C. Configure the physical switch to MTU 1600.
D. Disable the Distributed Switch MTU.
【单选题】
Which Host Profile Subprofile configuration is used to configure firewall settings for ESXi hosts?___
A. Advanced Configuration Settings
B. General System Settings
C. Security
D. Networking
【单选题】
Where would a vSphere administrator find general vCenter Server logs on a vCenter Server Appliance?___
A. /var/log/vmware/vpxd/
B. /var/log/messages
C. /etc/vmware-vpx/
D. /var/log/vmware/vsan-health/
【单选题】
An administrator wishes to enable network port mirroring based on source port. Which feature should be enabled?___
A. vSphere standard switch port
B. ERSPAN
C. NSX Virtual Wire
D. VLAN
【单选题】
Which CLI command shows the physical uplink status for a vmnic?___
A. esxcli network ip connection list
B. esxcli network ip neighbor list
C. esxcli network nic get
D. esxcli network nic list
【单选题】
Which is the maximum number of block devices (LUNs) that are supported by ESXi hosts that are running version 6.5?___
A. 1024
B. 512
C. 2048
D. 256
【单选题】
When performing a vCenter Server 5.5 for Windows with Microsoft SQL Server Express database migration to vCenter Server Appliance 6.5, which will be the target database?___
A. Microsoft SQL Server Express 2012R2
B. Microsoft SQL Server Standard 2012R2
C. PostgreSQL
D. Oracle DB 11g
【单选题】
An administrator has multiple vCenter Server 6.5 systems but cannot enable Storage I/O Control (SIOC) on a datastore shared by ESXi hosts managed by the vCenter Server systems. Which action should the administrator take to resolve the issue?___
A. Unmount the datastore and then enable SIOC on the vCenter Server system.
B. Configure the datastore to be managed by a single vCenter Server system.
C. Configure Storage DRS and then enable SIOC on the vCenter Server system.
D. Enable Raw Device Mapping (RDM) on the
E. SXi hosts.
