When the project is opened, you will need to double-click the controller to open the configuration window. Check off the Timer Register box and specify the %MW register that is desired for the timer. Build the project and download to the controller.
Below is a video that goes over setting up and configuring a timer register to hold the value of a free running counter, incrementing every 10ms. If the PLC stops the free running timer will stop incrementing.
Below is a video that goes over setting up and configuring a timer register to hold the value of a free running counter, incrementing every 10ms. If the PLC stops the free running timer will stop incrementing.