Rockwell Automation 1747-L55x,D174710.4 SLC 500 Ethernet - Manual (Page 12)

1–4 SLC 5/05 Ethernet Processor Features
Publication 1747-10.4
The processors include a 3-position keyswitch on the front panel that
lets you choose from three modes of operation: Run, Program, and
Remote. You can remove the key in any of the three positions.
!
ATTENTION: Depending on the size of your user
program, the processor can take up to 2.5 seconds to
change modes when you change the position of the
keyswitch from RUN to PROG or to REM. Do not use
the keyswitch in place of a hardwired master control
relay or an emergency-stop switch.
RUN Position
This position places the processor in the Run mode. The processor
scans/executes the ladder program, monitors input devices, energizes
output devices, and acts on enabled I/O forces. You can only change
the processor mode by changing the key position. You cannot
perform online program editing.
To change the mode to Run, turn the key from PROG or REM to
RUN. When the key is in the RUN position, you cannot use a
programmer/operator interface device to change modes.
PROG Position
This position places the processor in the Program mode. The
processor does not scan/execute the ladder program, and the
controller outputs are de-energized. You can perform online
program editing. You can only change the mode by changing the
key position.
To change the processor mode to Program, turn the key from REM
or RUN to PROG. When the key is in the PROG position, you
cannot use a programmer/operator interface device to change
modes.
REM Position
This position places the processor in the Remote mode: either the
REMote Run, REMote Program, or REMote Test mode. You can
change the processor mode by changing the keyswitch position or by
changing the mode from a programmer/operator interface device.
You can perform online program editing in this position.
To change the mode to REM, turn the key from RUN or PROG to
REM. When the key is in the REM position, you can use a
programmer/operator interface device to change modes.
Keyswitch Operation