Siemens Simantic S7-1500 - Meaning of LINK RX;TX LEDs

Interrupts, error messages, diagnostics and system alarms
4.1 Status and error displays of the CPU
CPU 1517T-3 PN/DP (6ES7517-3TP00-0AB0)
36 Manual, 12/2017, A5E36285525-AB
RUN/STOP LED
ERROR LED
MAINT LED
Meaning
LED flashes
yellow/green
LED flashes red LED flashes yellow
Startup (CPU booting)
Test of LEDs during startup, inserting a module.
LED flashing test
Meaning of LINK RX/TX LED
Each port has a LINK RX/TX LED. The table below shows the various "LED scenarios" of
ports for the CPU 1517T-3 PN/DP.
Table 4- 2 Meaning of the LEDs
LINK TX/RX LED
Meaning
LED off
There is no Ethernet connection between the PROFINET interface of the PROFINET device
and the communication partner.
No data is currently being sent/received via the PROFINET interface.
There is no LINK connection.
LED flashes green
The "LED flashing test" is being performed.
LED lit green
There is an Ethernet connection between the PROFINET interface of your PROFINET
device and a communication partner.
LED flickers yellow
Data is currently being received from or sent to a communications partner on Ethernet via
the PROFINET interface of the PROFINET device.