Bay Networks 24 Port BayStack 10base-T Hub VCCI-1 CG1001E02

here we're going to describe the difference between an Ethernet switch and an Ethernet hub and we're going to do so on a system that links an HMI panel to a PLC so right here is our HMI panel this is a human machine interface we can touch various buttons on the panel and access parameters within the panel is communicating via ethernet to this PLC so we're getting data from this PLC weeding data from it and display an order panel this panel is constantly sending query commands pulling the PLC for data in the PLC's memory now right now that link is being made through this Ethernet switch now the gray cable you see here in port one is the cable from the HMI so this is the HMI polling or querying data from the PLC which is the blue cable so gray cable HMI blue cable PLC you can see from the blinking LEDs we have activity in both ports the HMI on port one is sending data in the PLC is replyi