【单选题】
C.发电机容量大于变压器容量 D.不能确定12241.二次回路中文字符号 FU 表示___。
A. 熔断器
B. 电阻
C. 白炽灯
D. 远动信号
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相关试题
【单选题】
交流电流 I 通过某电阻，在一定时间内产生的热量，与某直流电流 I 在相同时间内通过该电阻所产生的热量相等，那么就把此直流电流 I 定义为交流电流 i 的(___。
A. 有效值
B. 最大值
C. 最小值
D. 瞬时值
【单选题】
有两个正弦量，其瞬时值的表达式分别为：u=220sin(ωt-10°),i=5sin(ωt-40°)，可 见(___。
A. 电流滞后电压 30°
B. 电流滞后电压 40°
【单选题】
C.电压超前电流 50° D.电流超前电压 30° 12246.三个相同的电阻串联总电阻是并联时总电阻的___。
A. 9 倍
B. 6 倍
C. 3 倍
D. 1／9
【单选题】
电感线圈在直流电路中相当于___。
A. 短路
B. 开路
C. 电压源
D. 大电阻
【单选题】
电力系统发生故障时，最基本的特征是(___。
A. 电压降低，电流增大
B. 电流增大，电压升高
【单选题】
C.电流减少，电压升高 D.电流减少，电压降低12255.微型计算机的硬盘正在工作时，应特别注意避免___。
A. 震动或突然断电
B. 使用鼠标
C. 噪声影响
D. 光线直射
【单选题】
下列不属于操作系统的是___。
A. WORD
B. WindowsXP
C. LINUX
D. Solaris
【单选题】
有一个直流电路，电源电动势为 10V，电源内阻为 1 欧姆，向负载 R 供电。此时负载从电源获得最大功率，则负载电阻 R 为___欧姆。
【单选题】
RLC 串联电路中，如果把 L 增大一倍，C 减小到原有的 1/4，则该电路的谐振频率变为原频率 f 的___。
A. 1.414 倍
B. 2 倍
C. 4 倍
D. 1/2 倍
【单选题】
D.在纯电感电路中，无功功率的最大值等于电路电压和电流的乘积12268.当变压器油温升高时，测温探头的电阻阻值___。
【单选题】
开关量输入光电隔离的电路要求是___。
A. 两个电源且各自接地，两地分开
B. 两个电源，共地C.交流、直流各一个电源 D.一个电源
【单选题】
测量电流互感器极性的目的是___。
A. 保证外部接线正确
B. 满足负载要求
C. 提高保护装置动作灵敏度
D. 提高保护可靠性
【单选题】
对于低压用电系统为了获得 380/220V 两种供电电压，习惯上采用中性点___构成三相四线制供电方式。
A. 直接接地
B. 不接地
C. 经消弧绕组接地
D. 经高阻抗接地
【单选题】
运行中的电流互感器一次侧最大负荷电流不得超过额定电流的___。
A. 2 倍
B. 1 倍
C. 5 倍
D. 3 倍
【单选题】
C.电流比误差 D.电压比误差12276.在变压器中性点装设消弧线圈的目的是___。
A. 补偿电网接地的电容电流
B. 限制变压器故障电流
C. 提高电网电压水平
D. 吸收无功
【单选题】
串行通信接口中常用的符号 TXD 表示___。
A. 发送数据信号
B. 接收数据信号
C. 接地信号
D. 同步信号
【单选题】
串行通信接口中常用的符号 RXD 表示___。
A. 接收数据信号
B. 发送数据信号
C. 接地信号
D. 同步信号
【单选题】
IEC870-5-101 规约中，若确认帧受到干扰或超时未收到确认帧时，则主站帧计数位 FCB 状态___。
A. 不变
B. 置 1
C. 置 0
D. 取反
【单选题】
IEC870-5-101 规约中规定非平衡式通信方式中，控制站不断召唤用户___。
A. 2 级数据
B. 3 级数据
C. 1 级数据
D. 2 级或 3 级数据
【单选题】
某线路更换 TA 重新投运后，后台显示的功率值和电流值均为线路实际负荷的一半，其可能原因是(___。
A. 线路的 TA 变比增大一倍
B. 变送器的
C. T 有一相被短接
【单选题】
C.变送器故障 D.线路的 TA 变比缩小了一倍12292.下列不属于监控系统站控层的设备是___。
A. 交流采样装置
B. 前置机
C. 数据通信网关
D. 操作员工作站
【单选题】
按照《DLT5149-2001220-500kV 变电所计算机监控系统设计技术规程》规定，变电站计算机监控系统的同期功能一般在___上实现。
A. 间隔层
B. 设备层
C. 站控层
D. 远方调度
【单选题】
C.事故追忆 D.事故及参数越限告警12295.IEC870-5-101 规约中类型标识 2E（十六进制）代表的含义是___。
【单选题】
10490e5716 此段报文中子站地址为___（转换为十进制）。
【单选题】
C.收发互不相关，独立传输 D.平衡或非平衡方式均可12299.关系数据库的规范化理论主要解决的问题是___。
A. 如何构造合适的数据逻辑结构
B. 如何构造合适的数据物理结构
【单选题】
C.如何构造合适的应用程序界面 D.如何控制不同用户的数据操作权限12300.___使用专用机床比较合适。
A. 大批量加工
B. 复杂型面加工
C. 齿轮齿形加工
D. 新产品试加工
【单选题】
精密加工是指___的加工技术。
A. 加工精度为 0.1μm、表面粗糙度为 Ra0.1～0.01μm
B. 加工误差小于 0.1μm、表面粗糙度小于 Ra0.01μm
C. 加工精度为 1μm、表面粗糙度为 Ra0.2～0.1μm
D. 加工精度为 2μm、表面粗糙度为 Ra0.8～0.2μm
【单选题】
数控车床 Z 轴步进电动机步距角为 0.36 度，电动机通过齿轮副或同步齿形带与滚珠丝杠联接，传动比为 5：6（减速），如 Z 轴脉冲当量为 0.01mm，问滚珠丝杠的螺距应为___。
A. 12mm
B. 10mm
C. 6mm
D. 5mm
【单选题】
关于干切削加工，___描述是不正确的。
A. 干切削机床最好采用立式机床，干铣削机床最好采用卧式机床
B. 干切削加工最好采用涂层刀具
C. 干切削适合加工尺寸精度和表面粗糙度要求高的非封闭零件
【单选题】
D.目前干切削有色金属和铸铁比较成熟，而干切削钢材、高强度钢材则存在问题较多13012.执行程序 M01 指令，应配合操作面板之___之开关。
A. OPTION STOP
B. “/”SLASH
C. COOLANT
D. DRY RUN
【单选题】
D.尾座套筒锥孔轴线对溜板移动不平行13021.机械效率永远是___。
【单选题】
下面___不是引起模拟进给伺服控制单元过电压报警的原因。
A. 直流母线的直流电压过低
B. 输入交流电压过高
C. 加、减速时间设定不合理
D. 机械传动系统负载过重
【单选题】
闭环控制系统比开环及半闭环系统___。
A. 精度高
B. 稳定性好
C. 故障率低
D. 效率高
【单选题】
数控机床是应用了数控技术的机床，数控系统是它的控制指挥中心，是用数字信号控制机床运动及其加工过程的。目前比较多的是采用微处理器数控系统，称为___系统。
A. CNC
B. CPU
C. CAD
D. RAM
【单选题】
机床数控系统的___是机床的移动部件（如工作台、刀架等），控制量是移动部件的位置（角度）和速度。
A. 控制对象
B. 控制信号
C. 控制操作
D. 控制点
【单选题】
数控机床水平调整以工作台为基准平面，常使用___精密水平仪来调整。
A. 2 个
B. 1 个
C. 3 个
D. 多个
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【单选题】
What happens to the status of users already logged into ESXi Shell when a vSphere administrator enables lockdown mode?___
A. Users remain logged in and can run commands, except to disable lockdown mode.
B. Users remain logged in and can run commands, including disabling lockdown mode.
C. Users are immediately logged out of ESXi Shell.
D. Users are logged out after a timeout specified by the vSphere administrator.
【单选题】
What is the effective vSphere licensing level during the 60 day evaluation period?___
A. vSphere Foundation Essentials Plus
B. vSphere Standard
C. vSphere Enterprise
D. vSphere
E. nterprise Plus
【单选题】
To comply with security requirements, an administrator with a vCenter Server Appliance needs to force logoff of the vSphere web client after 10 minutes of inactivity.What should the administrator do to meet the requirement?___
A. Edit: /var/lib/vmware/vsphere-client/webclient.properties, modify session.timeout=10
B. Edit: /opt/vmware/vsphere-client/webclient.properties, modify session.timeout=600
C. Edit: /var/lib/vmware/vsphere-client/webclient.properties modify session.timeout=600
D. Edit: /opt/vmware/vsphere-client/webclient.properties, modify session.timeout=10
【单选题】
An administrator enables High Availability (HA) on a Virtual SAN cluster.Which network is used for HA Network Heatbeat configuration?___
A. The Management network.
B. The vMotion network.
C. The Virtual SAN network.
D. The Provisioning Traffic network.
【单选题】
A user wants to monitor a business-critical virtual machine to ensure that it doesn't run out of resources. What metric could be monitored in vRealize Operations to address this concern?___
A. Time Remaining badge
B. Compliance badge
C. Reclaimable Waste badge
D. Density badge
【单选题】
An administrator has recently installed a new ESXi 6.x Host, and during the configuration notices sporadic network problems. To check whether the issue occurred sometime during the configuration, the administrator would like to reset the system.How can this be accomplished in the shortest amount of time?___
A. Run the ESXi installer again and reinstall the host.
B. Select the Reset System Configuration option from the vSphere Client when connected directly to the host.
C. From the
D. irect Console User Interface, select Reset System Configuration.
【单选题】
A vApp is running out of compute resources when overall activity is high within the resource pool. At other times, everything is fine.What should be done to resolve this issue?___
A. Increase the size of the resource pool Shares.
B. Set the vApp's CPU and Memory Reservation Type to Expandable.
C. Set the vApp's CPU and Memory Limit to Unlimited.
D. Create a new resource pool with the existing hardware configuration.
【单选题】
A virtual machine has been renamed and an administrator is unable to find files with the new virtual machine name in the datastore.What is the reason for this?___
A. The names of the files on the datastore do not change.
B. The names of the files on the datastore have been corrupted.
C. The virtual machine needs to be re-added to the inventory.
D. The Distributed Resource Scheduler moved the virtual machine to another host.
【单选题】
An administrator has configured network connectivity for a new virtual machine, as shown in the Exhibit.What will occur with the network traffic of this virtual machine when communicating externally from vSwitch1?___
A. The virtual machine will communicate on both uplinks
B. The virtual machine will only communicate on vmnic1
C. The virtual machine will only communicate on vmnic2
D. The virtual machine will fail to communicate externally
【单选题】
An administrator is unable to create the first group in a new vRealize Operations environment. What is the likely cause of the problem?___
A. There are no group types defined.
B. The group is not defined in SSO.
C. There are more than 32 group types defined.
D. The description for the group is not provided.
【单选题】
A new vApp was built and tested in the corporate headquarters datacenter running vSphere 6.x. What condition would explain why the virtual machine is failing to boot in an offsite datacenter running on vSphere 5.5?___
A. The virtual machine was built with the default hardware version.
B. The VMFS 5 datastore is not compatible with virtual machines configured with vSphere 6.x.
C. a
D. RS 5.5 cluster cannot run virtual machines configured with vSphere 6.x.
【单选题】
An administrator is evaluating whether to deploy vCenter Server on a Windows server or on a vCenter Server appliance. The administrator has the following requirements: <A web browser will be utilized to manage the vSphere environment.> <16 ESXi hosts will be deployed.> <Licenses must be shared with a vCenter Server at another site.> <An external Oracle 10g database server will be used to host the vCenter Server database.> Why will the administrator need to deploy vCenter Server on a Windows server?___
A. Linked Mode is a requirement for the solution.
B. Oracle 10g is a requirement for the solution.
C. The vSphere web client is a requirement for the solution.
D. Management of more than 5 hosts is a requirement for the solution.
【单选题】
What is a benefit of using VMware Data Protection ?___
A. Provides support for guest-level backups and restores of Microsoft SQL Servers, Exchange Servers, and Share Point Servers.
B. Provides support for advanced storage services including replication, encryption, deduplication, and compression.
C. Provides direct access to VDP configuration integrated into the vSphere Client.
D. Reduces disk space consumed by virtual machine data using deduplication.
【单选题】
An administrator enables vSphere High Availability (HA) on an existing cluster with a large number of hosts and virtual machines. The administrator notices that the setup of vSphere HA on some of the hosts is failing. What step, if taken, might resolve this issue?___
A. Increase the value of the config.vpxd.das.electionWaitTimeSec setting.
B. Set the value of vpxd.das.aamMemoryLimit to 256.
C. Set the value of the das.useDefaultIsolationAddress setting to False.
D. Increase the value of the das.iostatsinterval setting.
【单选题】
An ESXi 6.x host consists of 24 logical cores. Hyperthreading is enabled on the host. What is the maximum number of vCPUs that can be assigned to a virtual machine on this host?___
【单选题】
By default, each ESXi 6.x host is provisioned with a certificate from which root certificate authority?___
A. RedHat Certificate Authority
B. VMware Certificate Authority
C. DigiCert Certificate Authority
D. Verisign Certificate Authority
【单选题】
An administrator is adding an NFS datastore as shown in the Exhibit. What is the purpose of the Servers to be added list?___
A. It contains the IP addresses of the NFS Storage Server to provide multipathing capability.
B. It contains the IP addresses of the ESXi hosts that mount the datastore.
C. It contains the IP addresses used for
D. ynamic Discovery of targets.
【单选题】
An administrator reports that the System Event log data is only available for 24 hours when reviewing the Hardware Status tab. Which condition could be responsible for the loss of data?___
A. A Reset event log was executed.
B. The statistical collection level was set to a value of 1.
C. The boot disk of the host is corrupt.
D. Syslog has been configured at the vCenter Server level.
【单选题】
During an upgrade, the ESXi 6.x installer finds an existing version of ESXi and a VMFS3 volume. No virtual machines exist on the host or VMFS3 volume. The requirement is to upgrade to VMFS5. Which option should be chosen to meet this requirement?___
A. Upgrade ESXi and preserve the VMFS datastore
B. Install ESXi and preserve the VMFS datastore
C. Install ESXi and overwrite the VMFS datastore
D. Upgrade
E. SXi and overwrite the VMFS datastore
【单选题】
A vSphere 6.x Standard Switch is configured with 4 virtual machine portgroups, as shown in the exhibit. Which portgroup would be utilized by default when creating a new virtual machine?___
A. Access Network
B. DMZ Network
C. VM Network
D. Virtual Machine Network
【单选题】
Which vSphere 6.x feature will allow an organization to utilize native snapshots?___
A. Virtual Volumes
B. Virtual SAN
C. VMFS3
D. VMFS5
【单选题】
An administrator is creating a new vSphere Distributed Switch that will be utilized with a specific vSphere Cluster. The cluster itself contains a mix of ESXi 5.x and 6.x Hosts. Which Distributed Switch version should be created to support this configuration?___
A. Distributed Switch: 6.0.0
B. Distributed Switch: 5.0.0
C. Distributed Switch: 5.1.0
D. Distributed Switch: 5.5.0
【单选题】
Which load balancing policy, previously limited to vSphere Distributed Switches, is now available on vSphere Standard Switches with vSphere 6.x?___
A. Route based on physical NIC workload
B. Route based on IP Hash
C. Route based on the originating virtual port
D. Route based on Source MAC Hash
