Rockwell Automation 1747-PT1, D1747NP002 Hand-Held Terminal - Manual (Page 206)

Chapter 13
The Force Function
13–8
A forced external output circuit is independent of the internal logic of the
ladder program and the output data file. Installing forces on output circuits
only affects the output force table. Enabling installed forces does not affect
the output data file or the program logic. However, it does affect the output
circuit. The effects of installed and enabled forces can only be seen in the
Run mode. The Test mode does not energize output circuits.
The procedure for forcing an external output is the same as for forcing an
external input. However, the HHT always shows the logical state of the
instruction. For example, the following display shows output O:0/0 forced
off. The controller output LED is off, yet the rung and output data file show
the output to be logically true.
<
END
>
F RUN
ON OFF REM REM_ALL DISABLE
F1 F2 F3 F4 F5
OTE: O0:0.0/1 FORCE OFF 2.3.0.0.2
( ) ]/[
( ) ] [
] [
] [
( )
] [ ]/[
Function Key Description
[ F1 ], ON
Enters a 1 in the input force table for the cursored external
input bit address. This installs a force. If the Enable
function is in effect and the processor is in the Run or Test
mode, the force is applied. The data file bit remains forced
until: 1) the disable function is in effect, or 2) the force is
removed.
[ F2 ], OFF
Enters a 0 in the input force table for the cursored external
input bit address. This installs a force. If the Enable
function is in effect and the processor is in the Run or Test
mode, the force is applied. The data file bit remains forced
until: 1) the disable function is in effect, or 2) the force is
removed.
[ F3 ], REM
Affects the cursored external input bit address. If
applicable, removes the installed force from the force table
and the data file. Other forces are unaffected.
[ F4 ], REM_ALL
Affects all forced external input bit addresses and external
output circuits. Removes installed forces from all external
input bit addresses and output circuits. You must confirm
your choice.
[ F5 ], DISABLE
Toggles between enable and disable all forces, both inputs
and outputs. You must confirm your choice. The disable
function is in effect when no forces are enabled. Note that
the processor must be in the Run or Test mode to see the
effects of the forced input data bits.
Forcing an External Output