Rockwell Automation 1761-HHP-B30 MicroLogix 1000 with Hand-Held Programmer (HHP) - Manual (Page 355)

After You’ve Entered Your Program
Chapter 18
18–34
3. Confirm the deletion to remove the addresses.
ENT
Press ESC if you do not want to clear the list.
The Force function allows you to override the actual status of external input
circuits by forcing external input data file bits On or Off. You can also
override the controller logic and status of output data file bits by forcing
output circuits On or Off.
Important: Forces are always enabled but must be set to be active.
You can set forces while the controller is in any mode.
!
ATTENTION: To avoid possible personal injury and damage to
equipment, investigate the effects on machine operation before
forcing external input data file bits or external output circuits.
!
ATTENTION: Forces override any output control from either
the high-speed counter or from the output image. Forces may
also be applied to the high-speed counter inputs. Forced inputs
are recognized by the high-speed counter (e.g. forcing a count
input On and Off increments the high-speed accumulator).
Forcing External Input Data File Bits
Setting forces on input data file bits affects the input data file and also the
program logic. The effects on the program logic of set forces can be seen
from the program monitor and the data monitor functional areas when in
RRUN, RCSN, or RSSN.
The following is an example program monitor display of instruction I/6 in
rung 0. The display indicates that the controller is in RRUN and no forces
exist on this bit.
R 0 0 0
I / 6 0
Forcing Inputs and Outputs