EXFO ETS-1000L - Manual (Page 9)

Introducing the ETS-1000L
Ethernet Tester Analyzer 3
Overview
ACT
LED shows the data transmission state:
FDX
LED shows Ethernet interface state:
Power
LED lights up when the power supply unit is connected.
Data Transmission State LED Colors
Data is being transmitted or received
currently
green
No data is being transmitted or
received currently
off
Ethernet Interface State LED Colors
Full-duplex connection green
Half-duplex connection off