Timers

The timer function blocks are useful when you need an output to be dependent on the state of an input, but also require a delay. Delays with state changes are often needed when the communications equipment is known to be unreliable, for example, when you know that sensors sometimes report incorrect states due to signal interference.

These are the types of built-in timer function block:

• TOF—A false output is delayed by a specified amount of time.
• TON—A true output is delayed by a specified amount of time.
• TP—A pulse is output for a specified time.