Teseq’s CDN 117A series coupling-decoupling network enables convenient testing with surge pulses of 1.2 / 50 μs and ring wave impulses 0.5 μs / 100 kHz on data, signal or peripheral lines, as specified in many product standards. The test method, severity levels, permissible reaction of the EUT and specification of the coupling networks are included in IEC 61000-4-5 Ed.3 Chapter 188.8.131.52. Teseq’s CDN 118A series coupling-decoupling network enables convenient surge testing of telecommunications equipment to IEC / EN 61000-4-5 Ed.3 which, specifies a 1.2 / 50 μs or 10 / 700 μs pulse. The CDN 118A series includes the special decoupling network and coupling devices that are required for these tests. The design of the CDN is given in IEC 61000-4-5 Ed.3 Figure 10 and A.4.