Network Responses to Coupled Current by Electrical Fast Transient Disturbances to UTP Cable

초록

Abstract?In order to study susceptibility of a computer network by using an Electrical Fast Transient/Burst (EFT/B) test method, we composed a simple computer network and tested it experimentally. The test setup consisted of two hubs, three Unshielded Twisted Pair (UTP) cables, and two desktop Personal Computers (PCs). By using a ping utility at the PC1, states of network signal transmission were monitored during the EFT/B generator’s execution time. A Capacitive Coupling Clamp (CCC) was introduced to wrap the UTP cable between hub1 and hub2, as described in the international standard IEC 61000-4-4. Pulsed current coupled by the CCC was picked up by using high-frequency current sensors and recorded by an oscilloscope. For the test, 1 kV, 2 kV, 4 kV, 6 kV, and 7 kV of the EFT/B generator’s open voltages were arbitrarily selected. At the 4 kV and 6 kV of the open voltages, coupled peak current on the UTP wire reached 2.8 A and 4 A, respectively, and network data losses were displayed but not for all the test shots. Moreover, there was no data loss at 7 kV even though lower voltages did induce data losses. The probable reason for these results is that the EFT/B was not effectively synchronized with the moments when the pings were sent and received in the Ethernet system.