为使用451信号/频谱分析仪测量基频为5MHz的各次谐波的情况，标记报表中给出了基频、二次谐波和三次谐波的频率和幅度。扫频分析功能手动测量谐波根据标记报表我们可以方便的测量出各次谐波与基频信号之间的幅度差，以dB来表示。由于频谱分析仪通常显示对数功率（单位dBm），因此在计算谐波失真时，需要将相应的幅度量转换成电压。为了方便计算，根据如下推导公式可快速计算谐波失真。利用方法手动计算得到的信号谐波失真结果为3.679%。
PV032R1K1T1NGLC
PV032R1K4T1NFHS
PV032R1K8S1NFWS
PV032R1K8T1NMMC
PV032R1K1T1WFDS
PV032R1K1AYNMTP
PV032R1K1T1NHCC
PV032R1K1T1WMM1
PV032R1K1AYNMRZ
PV032R1K8T1NFWS
PV032R1K1A4NFTZ
PV032R1K1T1VMMC
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PV032L1E3C1NFWS
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PV032RAK1T1NF
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PV032R1K1T1VFDS
PV032R1K1T1N10045
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PV032R1K1T1NHLC
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PV032R9K1T1NMMC
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PV032R1K1T1NFRZ
PV032R1K1T1NMMK
PV032R1L1T1NMMC
PV032R1K4T1NMR1
PV032R1K1T1WMR1
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PV032R1K1T1NE1B
PV032R1K1T1NKLC
PV040R1K8T1NMMC
PV040L1K1T1NFWS
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PV040R1K1T1NFFP
PV040R1K4T1NMR1
PV040R1K1T1NMR1
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PV040R1K4T1NMMC
PV040R1K1T1NFDS
PV040R1K1T1NFF1
PV040R1K1T1NMRZ
PV040R1K1AYNMRZ
PV040R1K4T1NFHS
PV040R1K1T1WFDS
PV040R1K8T1VMMC
PV040R1K8T1N001
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PV040R1K4T1NFR1
PV040R1K1T1N001
PV040R1K8T1NFWS
PV040R1K1T1VFDS
PV040R1K1A4NFRZ
PV040R1K1T1NMRC
PV040R1K1T1NMM1
PV040R1K1T1WMM1
PV040R1K1T1NMRK
PV040R1K1T1NHCC
PV040R1K1T1NMF1
PV040R1K1JHNMMC
PV040L1K1T1NMMC
PV040R1K1S1NFWS
PV040R1L1T1NMMC
PV040R1D8T1N001
PV040R1K1T1NMFC
仪表放大器是一种具有差分输入和相对参考端单端输出的闭环增益单元。大多数情况下，仪表放大器的两个输入端阻抗平衡并且阻值很高，典型值≥109Ω。其输入偏置电流也应很低，典型值为1nA至50nA。与运算放大器一样，其输出阻抗很低，在低频段通常仅有几毫欧(mΩ)。运算放大器的闭环增益是由其反向输入端和输出端之间连接的外部电阻决定。与放大器不同的是，仪表放大器使用一个内部反馈电阻网络，它与其信号输入端隔离。对仪表放大器的两个差分输入端施加输入信号，其增益既可由内部预置，也可由用户通过引脚连接一个内部或者外部增益电阻器设置，该增益电阻器也与信号输入端隔离。
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PV040R1K1T1WFR1
PV040R1K1T1NKLC
PV040R9K1T1NFWS
PV040R1K1T1NFFC
PV040R1K1T1NF
PV040R1K1T1N100
PV040R1K1T1WMR1
PV040R1K1T1NFRZ
PV040R1K1T1WMRC
PV040R1K1T1NMMK
PV040R1K1T1NMMC
PV040R1K1T1VMMC
PV040R1K1T1NFHS
PV040R1K1T1NGLC
PV040R1K1T1NHLC
PV040R1K1T1WMMC
PV040L1L1T1NFWS
PV040R1K1T1NMLC
PV040R1D1T1NGCC
PV040R1K1T1NELA
PV040R9K1T1NMMCK0188
PV046R1K1T1N001
PV046R1K1T1N100
PV046R1K1T1NFDS
PV046R1K1T1NFR1
PV046R1K1T1NFHS
PV046R1K1T1NMMC
PV046R1K1T1NMM1
PV046R1K1T1NMRC
PV046R1K1T1NFWS
PV046R1K1T1NFRC
PV046R1K1T1NFF1
PV046R1D1T1NFWS
PV046R1D3T1NFFC
PV046R1K1A1NF
PV046L1K1A1NFHS
PV046R1K1B1NFDS
PV046R1D1T1NHCC
PV046R1K1T1NFFC
PV046R1K1T1NMFC
PV046R1K1T1NMF1
PV046R9K1T1NMMC
PV046R1K1AYNMRC
PV046R1K1JHNMMC
PV046R9K1T1NFWS
PV046R1K4T1NMR1
PV046R1K4T1NFHS
PV046L1K1T1NFWS
PV046R1K1S1NFWS
PV046R1K1T1WFDS
PV046R1K1T1NMRZ
PV046R1K1T1EMMC
PV046R1K1T1WMMC
PV046R1K1T1NFFP
PV046R1K1A4NFRC
PV046R1K1T1VFDS
PV046R1K8T1NFWS
PV046R1K1T1WMM1
PV046L1K1T1NMMC
PV046R1K8T1VMMC
PV046R1K8T1NMMC
PV046R1K1T1NF
PV046R1K1AYNMRZ
PV046R1K1T1NHLC
PV046R1K1T1NMMK
PV046R1K1T1NKLC
PV046R1K1T1NMR1
PV046R1K1T1NFRZ
PV046R1K1T1WFR1
PV046R1K4T1NFR1
PV046R1K1T1WMR1
PV046R1K1T1NMRK
PV046R1K1T1WMRC
PV046R1K1T1NHCC
PV046R1K1T1VMMC
PV046R1K1T1NGLC
PV046R1L1T1NMMC
PV046R1K8T1N001
PV046R1K4T1NMMC
PV046R1K1T1NMMCX5934
PV063R1K1T1NMF1
PV063R1K1T1NMMC
PV063R1K1T1NMMK
PV063R9L1TNMPCK0
PV063R1K1A1VFPR
PV063R1K1C1NFWS
PV063R2K1T1N001
PV063R9L1T1NFWS
PV063R1K1A1NFHS
PV063R1K1T1NFFP
PV063R1K1T1NFPR
PV063R1K1T1NGLC
PV063R1K1T1N001
PV063R1K1T1N100
PV063R1K1T1NFDS
机械冲击：过大的冲击转矩往往造成电机笼条，端环断裂和定子端绕组绝缘破损，导致击穿烧机，转轴扭曲，联轴节、传动齿轮损伤和皮带撕裂等；3.对生产机械造成冲击：起动过程中的压力突变往往造成泵系统管道、阀门的损伤，缩短使用寿命；影响传动精度，甚至影响正常的过程控制。所有这些都给设备的安全可靠运行带来威胁，同时也造成过大的起动能量损耗，尤其当频繁起停时更是如此。为避免对电网和设备造成严重影响，大功率电机在启动时一般采用如下两种方式。
