【单选题】
可编程序控制器在输入端使用了___，来提高系统的抗干扰能力。
A. 晶闸管
B. 继电器
C. 晶体管
D. 光电耦合器
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相关试题
【单选题】
PLC梯形图编程时，输出继电器的线圈并联在___。
【单选题】
在FX2N PLC中，T200的定时精度为___。
A. 1ms
B. 10ms
C. 100ms
D. 1s
【单选题】
将程序写入可编程序控制器时，首先将___清零。
A. 计数器
B. 存储器
C. 计时器
D. 计算器
【单选题】
对于可编程序控制器电源干扰的抑制，一般采用隔离变压器和___ 来解决。
A. 直流发电机
B. 交流整流器
C. 交流滤波器
D. 直流滤波器
【单选题】
PLC外部环境检查时，当湿度过大时应考虑装___。
A. 除尘器
B. 风扇
C. 空调
D. 加热器
【单选题】
根据电动机顺序启动梯形图，下列指令正确的是___。
A. ORI Y001
B. ANDI T20
C. AND X001
D. AND X002
【单选题】
根据电动机自动往返梯形图，下列指令正确的是___。
A. LDI X002
B. ORI Y002
C. AND Y001
D. ANDI X003
【单选题】
对于晶体管输出型PLC，要注意负载电源为___，并且不能超过额定值。
A. AC600V
B. DC220V
C. DC24V
D. AC220V
【单选题】
变频器是通过改变交流电动机定子电压、频率等参数来___的装置。
A. 调节电动机转速
B. 调节电动机转矩
C. 调节电动机功率
D. 调节电动机性能
【单选题】
交—交变频装置通常只适用于 ___拖动系统。
A. 低速大功率
B. 高速大功率
C. 低速小功率
D. 高速小功率
【单选题】
在SPWM逆变器中主电路开关器件较多采用___。
A. MCT
B. 普通晶闸管
C. GTO
D. IGBT
【单选题】
FR-A700系列是三菱___变频器。
A. 节能型轻负载
B. 水泵和风机专用型
C. 多功能高性能
D. 经济型高性能
【单选题】
变频调速时电压补偿过大会出现___情况。
A. 负载重时，不能带动负载
B. 负载轻时，电流过小
C. 负载轻时，电流过大
D. 电机转矩过小，难以启动
【单选题】
负载不变情况下，变频器出现过电流故障，原因可能是：___。
A. 负载过重
B. 电源电压不稳
C. 转矩提升功能设置不当
D. 斜波时间设置过长
【单选题】
异步电动机的启动电流与启动电压成正比，启动转矩与启动___成正比。
A. 电流
B. 电压
C. 电流的二次方
D. 电压的二次方
【单选题】
软启动器的晶闸管调压电路组件主要由动力底座、___、限流器、通信模块等选配模块组成。
A. 控制单元
B. Profibus模块
C. 隔离器模块
D. 热过载保护模块
【单选题】
西普STR系列___软启动器，是内置旁路、集成型。
【单选题】
就交流电动机各种启动方式的主要技术指标来看，性能最佳的是___。
A. 变频启动
B. 软启动
C. 串电阻启动
D. 串电感启动
【单选题】
软启动器的功能调节参数有： ___、启动参数、停车参数。
A. 运动参数
B. 电阻参数
C. 电子参数
D. 软启动
【单选题】
软启动器的主电路采用___交流调压器，用连续地改变其输出电压来保证恒流启动。
A. 晶闸管变频控制
B. 晶闸管PWM控制
C. 晶闸管相位控制
D. 晶闸管周波控制
【单选题】
凝露的干燥是为了防止因潮湿而降低软启动器的___，及其可能造成的危害。
A. 使用效率
B. 绝缘等级
C. 接触不良
D. 散热效果
【单选题】
光电开关的接收器根据所接收到的光线强弱对目标物体实现探测，产生___。
A. 频率信号
B. 开关信号
C. 压力信号
D. 警示信号
【单选题】
光电开关可以___、无损伤地迅速检测和控制各种固体、液体、透明体、黑体、柔软体、烟雾等物质的状态。
A. 电磁感应
B. 非接触
C. 小电流
D. 高亮度
【单选题】
当检测远距离的的物体时，应优先选用___光电开关。
A. 光纤式
B. 槽式
C. 漫反射式
D. 对射式
【单选题】
光电开关的配线不能与___放在同一配线管或线槽内。
A. 光纤线
B. 网络线
C. 动力线
D. 电话线
【单选题】
高频振荡电感型接近开关主要由感应头、振荡器、开关器、___等组成。
A. 发光二极管
B. 光电三极管
C. 继电器
D. 输出电路
【单选题】
高频振荡电感型接近开关的感应头附近有金属物体接近时，接近开关___。
A. 涡流损耗减少
B. 无信号输出
C. 振荡减弱或停止
D. 振荡电路工作
【单选题】
当检测体为___时，应选用电容型接近开关。
A. 透明材料
B. 金属材料
C. 非金属材料
D. 不透明材料
【单选题】
选用接近开关时应注意对工作电压、负载电流、响应频率、___等各项指标的要求。
A. 检测电流
B. 工作速度
C. 检测功率
D. 检测距离
【单选题】
磁性开关可以由___构成。
A. 二极管和电磁铁
B. 接触器和按钮
C. 永久磁铁和干簧管
D. 三极管和永久磁铁
【单选题】
磁性开关中的干簧管是利用___来控制的一种开关元件。
A. 电流信号
B. 温度信号
C. 磁场信号
D. 压力信号
【单选题】
磁性开关用于高温高压场所时应选___的器件。
A. PP、PVDF材质
B. 多层纸质
C. 金属材质
D. 晶体材质
【单选题】
磁性开关在使用时要注意磁铁与___之间的有效距离在10mm左右。
【单选题】
增量式光电编码器主要由光源、码盘、___、光电检测器件和转换电路组成
A. 光电三极管
B. 脉冲发生器
C. 检测光栅
D. 运算放大器
【单选题】
增量式光电编码器每产生一个___就对应于一个增量位移。
A. 输出电压信号
B. 输出光脉冲
C. 输出脉冲信号
D. 输出电流信号
【单选题】
增量式光电编码器由于采用相对编码，因此掉电后旋转角度数据___，需要重新复位。
A. 变大
B. 不会丢失
C. 变小
D. 会丢失
【单选题】
增量式光电编码器根据信号传输距离选型时要考虑___。
A. 输出信号类型
B. 电源频率
C. 环境温度
D. 空间高度
【单选题】
可编程序控制器采用大规模集成电路构成的___和存储器来组成逻辑部分。
A. 运算器
B. 微处理器
C. 控制器
D. 累加器
【单选题】
可编程序控制器系统由基本单元、___、编程器、用户程序、程序存入器等组成。
A. 扩展单元
B. 键盘
C. 鼠标
D. 外围设备
【单选题】
在一个程序中，同一地址号的线圈___次输出，且继电器线圈不能串联只能并联。
A. 无限
B. 只能有一
C. 只能有二
D. 只能有三
推荐试题
【多选题】
Which two statements are true regarding Auto Deploy in version 6.5? (Choose two.)___
A. Auto Deploy can be configured and managed via PowerCLI.
B. Auto Deploy can be configured and managed via the vSphere Client.
C. Auto
D. eploy can be configured and managed via the vSphere Web Client.
【多选题】
What three options can improve network performance for a virtual machine? (Choose three.)___
A. MLD
B. TSO
C. NetFlow
D. LRO
E. SR-IOV
【多选题】
Which two storage technologies are supported for MSCS? (Choose two.)___
A. NFS
B. VAAI
C. iSCSI
D. FC
【多选题】
When upgrading a VMware vSAN cluster to version 6.5, which two tasks must be completed to comply with upgrade requirements and VMware-recommended best practices? (Choose two.)___
A. Use RVC to upgrade the hosts.
B. Use the latest available ESXi version.
C. Back up all VMs.
D. Use only the “Full data migration” maintenance mode option.
【多选题】
What two enhancements are in VMFS6 but not in VMFS5? (Choose two.)___
A. Support for 4k native disks
B. Support for 512e disks
C. GPT storage device partitioning
D. Automatic space reclamation
【多选题】
Which two statements describe why a vSphere DRS cluster would report load imbalance? (Choose two.)___
A. The configured migration threshold is too high.
B. The configured migration threshold is too low.
C. DRS is configured for Partially Automated.
D. Enhanced vMotion Compatibility (EVC) is enabled.
【多选题】
A vSphere Administrator must ensure that vCenter Server service is running in a domain user account rather than Local System Account. To accomplish this, the user account should have which two permissions? (Choose two.)___
A. Log on as a service.
B. Act as part of the operating system.
C. Log on as a batch job.
D. Log on locally.
【多选题】
A virtual machine fails to power on after being deployed from a template. What two remediation steps could correct this issue? (Choose two.)___
A. Increase CPU reservation
B. Decrease memory reservation
C. Increase memory reservation
D. Increase datastore capacity
E. Decrease CPU reservation
【多选题】
Which three directories are available under the vcsa-cli-installer folder of the vCenter Server Appliance installation media? (Choose three.)___
A. \mac
B. \ovftool
C. \migration-assistant
D. \win32
E. \lin64
【多选题】
What are three considerations when booting ESXihost from SAN software FCoE? (Choose three.)___
A. The VMware_FCoE_vSwitch that the installer automatically created cannot be changed.
B. Boot LUN cannot be shared with other hosts even on shared storage.
C. Multipathing is not supported at pre-boot.
D. Software FCoE boot configuration cannot be changed from within
E. SXi.
【多选题】
Which two choices are applicable to vSphere Availability? (Choose two.)___
A. Heartbeat Datastores
B. VM Startup/Shutdoown
C. Power Management
D. Admission Control
【多选题】
A user is a member of groups A and B. -VM10 and VM20 are in VM Folder. -Group A is assigned permission “Read-only” on VM Folder. What two configurations will allow the user to edit the settings for only VM10? (Choose two.)___
A. Assign group B permission “virtual machine power user” to VM10.
B. Assign group B permission “virtual machine console user” to VM10.
C. Assign group A permission “virtual machine console user” to VM10.
D. Assign group A permission “virtual machine power user” to VM10.
【多选题】
Which two new vSphere 6.5 features enable an Administrator to locate configuration options when creating or editing host profiles more easily than in previous versions? (Choose two.)___
A. Add the configuration option to favorites.
B. Navigate the option tree.
C. Search for the configuration option.
D. Copy the configuration option from a different profile.
【多选题】
What are the two valid storage controller types for VMs on ESXi 6.5? (Choose two.)___
A. FCoE
B. SATA
C. NVMe
D. iSCSI
【多选题】
Which two options can optimize conversion with VMware Converter? (Choose two.)___
A. Disable real-time antivirus scanners.
B. Remove the source from Active Directory.
C. Remove third-party device drivers.
D. Exclude diagnostic partitions from conversion.
E. Disable Volume Shadow Copy (VSS).
【多选题】
vSphere Availability considers which two factors for virtual machine restarts? (Choose two.)___
A. Host Isolation Response
B. file accessibility
C. NUMA node size
D. resource reservations
【多选题】
Which two virtual NICs support Wake-on-Lan to resume a virtual machine that is in standby mode? (Choose two)___
A. Flexible
B. E1000E
C. E1000
D. vmxnet 3
【多选题】
Which two logs should be examined to troubleshoot a Windows vCenter Server upgrade failure? (Choose two.)___
A. vminst.log
B. vim-um-msi.log
C. firstboot.log
D. pkgmgr.log
【多选题】
Which are two supported storage primitives for VAAI NAS? (Choose two.)___
A. Full File Clone
B. Reserve Space
C. hardware assisted locking
D. block zeroing
【多选题】
Which two parameters must be configured for Windows in-guest disk mirroring? (Choose two.)___
A. scsi#.returnNoConnectDuringAPD = “FALSE”
B. scsi#.terminateVMOnPDL = “TRUE”
C. scsi#.returnBusyOnNoConnectStatus = “FALSE”
D. scsi#.returnNoConnectDuringAPD = “TRUE”
【多选题】
Which two items are required to enable NPIV in a virtual machine? (Choose two.)___
A. use of physical RDMs
B. physical HBA support
C. use of virtual disks
D. hardware version 11 or higher
【多选题】
A vSphere Administrator has VM Component Protection (VMCP) enabled, but the VM was not restarted when one of the VMFS datastores experienced an All Paths Down (APD) failure. What two scenarios would explain why the virtual machine was not restarted? (Choose two.)___
A. VM Monitoring is required in order for VMCP to failover during an APD event.
B. VMware Tools is not installed on the guest operating system for the VM.
C. Insufficient Capacity is available on the failover ESXi hosts.
D. The APD failure was corrected before the VM could be restarted.
【多选题】
What are two requirements in order to restore a Resource Pool Tree from a snapshot? (Choose two.)___
A. vSphere DRS must be turned on.
B. A restore can only be performed on a vSphere DRS cluster within the original vCenter Server.
C. vSphere
D. RS must be turned off.
【多选题】
Which three vSphere features are compatible with vSphere Replication? (Choose three.)___
A. vSphere High Availability
B. vSphere Fault Tolerance
C. vSphere Storage
D. RS
【多选题】
What two VMware Remote Console Options can be defined in the virtual machine settings? (Choose two.)___
A. Boot Delay
B. Maximum number of sessions
C. Guest OS lock
D. Total video memory
【多选题】
VMware Converter can import a powered off virtual machine from which two virtual machine platforms?(Choose two.)___
A. Microsoft Hyper-V
B. Citrix Xen
C. VMware Workstation
D. Linux with KVM
【多选题】
Which two options allow storage space reclamation? (Choose two.)___
A. Use VMFS6 datastores.
B. Use esxcli storage vmfs unmap.
C. Use the SAN console (management tool).
D. Use the vSphere Web Client.
【多选题】
An administrator must reprovision 25 hosts with a new image profile that he has created. Which two methods can the administrator use to change the image profile? (Choose two.)___
A. From the vSphere Web client home page, select the Deploy Rules tab in the Auto Deploy section.
B. Run the Copy-Deploy Rule and specify the Replace Item parameter with Power CLI.
C. From the vSphere Web client home page, select the Assign Rules tab in the Auto
D. eploy section.
【多选题】
What are three parameters for traffic filtering or marking? (Choose three.)___
A. Protocol
B. Traffic Direction
C. DSCP value
D. virtual Port ID
【多选题】
The vSphere administrator must change the path selection policy (PSP) to comply with best practices. Which two interfaces can be used to change the PSP? (Choose two.)___
A. ESXi shell
B. vSphere Client
C. ESXi host client
D. vSphere Web Client
【多选题】
In what two ways can Storage DRS load balance virtual machines? (Choose two.)___
A. anti-affinity rules
B. virtual storage controller
C. guest OS family
D. I/O latency
【多选题】
What two reasons can explain why a host cannot be removed from a vSphere Distributed Switch? (Choose two.)___
A. There are virtual machine network adapters connected to the switch.
B. There are blocked ports on the switch.
C. There are LACP LAGs configured on the switch.
D. There are VMkernel network adapters connected to the switch.
【多选题】
Which three requirements are true for the vCenter Server HA network? (Choose three.)___
A. Network latency between all nodes must be less than 10 milliseconds.
B. IP addresses for all nodes must be static.
C. HA network IP addresses for all nodes can be on different subnets.
D. IP addresses must be on the same network as the management network.
E. A default gateway must be configured.
【多选题】
Which two statements correctly describe Normal Lockdown Mode? (Choose two.)___
A. ESXi Shell and SSH services are independent of lockdown mode.
B. In normal lockdown mode the DCUI service is stopped.
C. ESXi Shell and SSH services are dependent of lockdown mode and cannot be configured.
D. In normal lockdown mode the DCUI service is running.
【多选题】
The Health check feature in the vSphere Distributed Switch helps troubleshoot network connectivity. What three checks does this feature perform? (Choose three.)___
A. Network Utilization
B. MTU
C. Teaming and Failover
D. VLAN
【多选题】
What are the three types of nodes in a vCenterServer HA cluster? (Choose three.)___
A. Master
B. Replica
C. Witness
D. Active
E. Passive
【多选题】
What are two consequences of turning off vSphere DRS on a cluster? (Choose two.)___
A. vMotion capability will be lost.
B. Resource pools will be lost.
C. vApps will be lost.
D. Affinity rules will be lost.
【多选题】
Which two protocols can be used to back up vCenter Server Appliance Instance? (Choose two.)___
A. iSCSI
B. HTTPS
C. FTP
D. NFS
【多选题】
What are two requirements to enable EVC in a vSphere DRS cluster? (Choose two.)___
A. CPU must be in the same family and of the same speed.
B. CPUs must be from the same vendor.
C. EVC must use the lowest possible baseline supported by the hardware.
D. No VMs may be running in the cluster.
【多选题】
In Advanced settings on a vSphere host, Security.Password Quality Control set as retry=3 min=disabled, disabled, disabled, 7, 7 . Which two passwords are valid? (Choose two.)___
A. xQaT3#A
B. P@ssw0rd
C. xQaTEh2
D. Xqat3h!
E. xQaTEhb!
