Forcing is a two-step process. You must add a force to the item to be tested. Then forces must be enabled.
Enabling forces is global in the controller. It will enable all forces in that controller, so before you enable, you must verify if there are existing forces other than your own. If there are, make sure you understand what effect they have, Otherwise you could be enabling other forces and you might not be aware of the impact or reason behind that force. Also, once forces are enabled, all future forces will be enabled immediately.
Likewise disabling forces is also global to that controller. If you disable forces, you could again be affecting other parts of the system that you are not familiar with.
This two-step process is intended to prevent people that do not understand how forcing works from affecting live systems. They must understand how forcing inputs impacts the system versus what affect forcing an output has. They are very different in how the system
Someone that doesn't know what they are doing can pretty easily add forces to their programs. But if they don't know how to enable it, then they are not affecting that live system. However, it cannot prevent people from posting messages asking why it isn't working. I would ask myself, do I fully understand how forcing works in this Allen-Bradley controller before I started forcing items and enabling and disabling. Forcing, and its effect on a system in A-B PLCs can be very different from other brands. Particularly in the way inputs and outputs are affected.
OG