3Com Switch 40x0 Family — Rear View Detail 19* The PSU LEDs are visible on the front of the Switch and are marked ‘1’ for PSU 1 (bottom) and‘2’ for PSU 2 (top).3Com Switch 40x0Family — Rear ViewDetailFigure 4 3Com Switch 40x0 Family — rear viewExpansion ModuleSlotYou can use this slot to install an Expansion Module. Contact yoursupplier for further information.TemperatureRed flashing The Switch and/or the PSUs are above criticaltemperature and may shut down.Off The Switch and the PSUs are below criticaltemperature.Expansion Module Status LEDsGreen The module is installed and supported and a link ispresent.Yellow The module is installed and supported but there is nolink present or the link status cannot be determined.Yellow flashing The Module is installed but not supported or has failedself-test. Note that the unit will continue to operatenormally.Off The Module is not installed.Expansion Module Packet LEDsYellow Packets are being transmitted/received on the port.Off No packets are being transmitted/received on the port.LED Color IndicatesDUA1770-9AAA04.book Page 19 Monday, April 14, 2003 11:33 AM
