Siemens SINUMERIK FM-NC Installation And Startup Manual page 83

12.98
03.96
PLC status
The following LEDs are located on the front plane of the NCU module
(see Fig. 5-1, Page 5-77)
displays
PR
PS
PF
PFO
–
PR and PS LEDs
Table 5-3
PR
LED
PS
LED
Meaning
RUN:
The PLC program is being processed.
STOP:
The PLC program is not being processed. STOP can be set by the PLC pro-
gram, error identifiers or an operator input.
HALT:
"Halts" the PLC user program (initiated by test function).
RESTART:
The control is started (transition from STOP to RUN state). If the start process is
aborted, the control switches back to the STOP state.
PF LED This LED lights up when the PLC watchdog has responded.
PFO LED A defined value is assigned to a variable by means of the FORCE function. The
variable is write-protected and cannot be changed from any location. The write
protection remains effective until it is canceled by the UNFORCE function. If the
PFO LED is off, then no FORCE job is present.
Profibus LED
The PROFIBUS LED is the BUSF LED on the SIMATIC CPU 315–DP.
For a description, please consult the Hardware and Installation Manual.
Note
If all 4 LEDs on the status display flash simultaneously after the NCU hardware
has been replaced, then another NCK power-up must be initiated. A PLC gen-
eral reset can then be executed if required.
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SINUMERIK 840D Installation and Start-Up Guide (IAD) – 04.00 Edition
They display the PLC operating states:
.
PLC RUN (green)
PLC STOP (red)
PLC watchdog (red)
PLC FORCE (yellow)
PROFIBUS (yellow)
Statuses displayed by PR and PS LEDs
lights off flashes
up at
0.5 Hz
off lights lights
up up
RUN STOP HALT
5 Power On and Power-Up
5.2 Power on and power-up
flashes off off
at 2 Hz
lights – lights up – lights up
up – off for 3 secs. – flashes at
– lights up 2 Hz (min.
3 secs.)
– lights up
RE- GENERAL RE- GENERAL RE-
START SET requested SET in progress
5
5-83