How do I latch a timer on in Unity Pro (Ladder)

I have an object running down a conveyor and when it passes a sensor I want a timer to start running.

Due to the object being short it passes the sensor and the timer stops rather than latching on for the duration of the preset time.

How do I latch the timer on?

Sorry if this is a stupid question.

Thanks for your help,

Dan Bowles

use TP timer (timer pulse) or set bit when you see object and reset bit when timer (TON) elapses.

It's been a while since I've used Unity, but in Logix I will often use the TT (The timing bit indicates that a timing operation is in process) in parallel with the input condition. This keeps the timer latched on as long as the the accumulated value is non-zero and the done bit isn't set.

That being said, if Unity has it, the TP timer is pretty awesome for these situations.