Rockwell Automation Safety Guidelines for the Application, Installation, and Maintenance of Solid-State Control - Manual (Page 22)

Publication SGI-1.1 - August 2009
22 Section 4: Installation Guidelines
Many programmable systems provide capability for "force on" and "force
off" of inputs and outputs. Use of these functions can reduce
troubleshooting and maintenance time by enabling personnel to bypass
certain operations without physically operating switches on a machine.
Care must be taken when using "force" functions to avoid exposing
personnel to hazardous machine motions or process operations.
For controllers operating a machine tool or robot, running a part program
at a fraction of the programmed operating speed with a workpiece of soft
material is considered "good practice". This allows an operator to observe
possible interference of tooling with the part and make corrections to the
program. A workpiece of soft material such as wood, plastic, or
machinable wax will minimize risk of tool damage if there is a tool crash
with the workpiece.