Siemens SINUMERIK ONE NCU 1740 - Page 36

Meaning of the RDY, COM, DIAG and SD Activity NCU LEDs
Name Function Status Meaning
RDY Ready
LED lights up red
There is at least one fault (e.g. RESET, watchdog monitoring etc.) or
the NCU is ramping up.
LED 󹪞ashes red (2 Hz)
Not assigned (SINAMICS boot error).
LED lights up yellow
Ramping up the NCU.
LED 󹪞ashes yellow
(0.5 Hz)
Firmware update of the connected DRIVE-CLiQ components
LED 󹪞ashes yellow (2 Hz)
Firmware update is complete for components. Wait for POWER ON
for the components in question.
LED lights up green
NC ramped up and everything in cyclic mode
LED 󹪞ashes
green/orange or
red/orange (1 Hz)
LED-supported detection of connected DRIVE-CLiQ component is
activated: (p0124[0] = 1).
COM Communi‐
cation
LED o󹪜
CP not ramped up / started
LED lights up green
Communication via CP possible (RUN operating state)
LED 󹪞ashes green
Communication possible (no con󹪝guration)
LED lights up yellow
CP was stopped via PLC/TIA. No communication.
LED 󹪞ashes yellow
Con󹪝guration received and transition to the RUN operating state.
LED 󹪞ashes red
Error status (FATAL error)
Description
4.4 Operator control and display elements
NCU 1740
36 Equipment Manual, 10/2021, A5E51087503B AA