Schwarzbeck CDN AF4 Coupling Decoupling Network

The CDN AF4 is part of the coupling decoupling network series for conducted common mode immunity testing according to IEC 61000-4-6. The CDN AF4 is compliant to IEC 61000-4-6 Annex D3 and is suitable for immunity testing on unscreened and unbalanced control lines with moderate currents.

The CDN AF4 is intended to inject common mode disturbance signals to control lines in the frequency range 150 kHz to 230 MHz. The circuitry is shown in Fig. 5.

All CDNs comply to the requirements of IEC 61000-4-6. Each CDN comes with individually measured data and a calibration certificate for the common mode impedance and the voltage division factor. Further typical data can be found in fig. 3 and fig. 4

A variety of calibration adapters and other accessories is available as option.

Important Note: The optional shorting adapters must not be used if the CDN is connected to mains! The capacitors at the AE-side are not equipped with discharging resistors.

The connection to ground can be accomplished using the ground plane of the CDN. Additionally there is a M4 thread located at the AE side to ground as well as a 4 mm socket to connect the device to ground.

To improve the operational safety the connections are carried out as security sockets. We recommend to use special 4 mm security plugs if you plan to design your own adapters. Those connectors can be purchased optionally.

Fig. 1: typ. EuT common mode impedance	Fig. 2: typ. phase EuT-Port, common- mode
Fig. 3: typical voltage division factor RF-port to EuT port	Fig. 4: typ. isolation AE to RF-port