测量方法是使受试设备在骚扰源作用下形成的电场和磁场来模拟来自实际发射机的电场和磁场。这些骚扰场是由试验配置所产生的电压或电流所形成的近区电场和磁场来近似表示的。用耦合和去耦装置提供騷扰信号给某一电缆，保持其他电缆不受影响，只近似于骚扰源以不同的幅度和相位范围作用于全部电缆的实际情况。
EM clamp for immunity testsacc. EN 61000-4-6 (2014-08) Ed. 4.0
Features:
EM clamp for immunity testing of cables with up to 20 mmdiameter
High coupling factor: less than 15 watts amplifier output poweris required to obtaina test level of 10 V
Calibration unit and calibration data are supplied with eachinstrument
Description:
The preferred coupling and decoupling devices are the CDNs, forreasons of testreproducibility and protection of the AE. However,if they are not suitable or ailable,clamp injection should beused.
Often, clamp injection needs to be applied to multi-pair balancedcables because suitableCDNs might not be ailable.
The EM clamp establishes both capacitive and inductive coupling tothe cable connectedto the EUT.
The EM clamp (in contrast to the conventional current injectionclamp) has a directivity ≥10 dB, above 10 MHz, so that a definedimpedance between the common-mode point ofthe AE and the groundreference plane is no longer required. Above 10 MHz, thebehiour ofthe EM clamp is similar to that of a CDN.
CDN-EMCL (EMCL-20), EM clamp acc. EN 61000-4-6 forcables up to 20mm diameter,incl. calibration unit and calibration data
Calibration set for CDN-EMCL for upgrade of newstandard IEC61000-4-6 Ed. 4, 2014
Attenuator 6dB, 20W, BNC-Connector male / female;weight approx. 90g (optional for CDG 6000)
Adaptor N-plug / BNC-jack (included by CDN-EMCL)
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