How to disable a timer's preset?

I'm working in logix 5000 and I using an RTO timer to keep track of the total running time of a conveyor. Each day the timer will be reset back to zero.

Since I'm not using the preset function of the timer, is there a way I can disable or ignore the preset?

Could I simply use a preset value of 0 or something?

-Pete

You could set the timer preset to the max time allowed for it. Or you could set the timer to 6 seconds and use it to increment an integer, and keep count in tenths of minutes there.

as jtn suggested, most programmers would just set it for the max and forget it ...

try 2,147,483,647 (note: leave the commas out when you enter the value) ...

As an alternative, if you have the RSLogix5000 Pro or the extensions for ST or FB languages you can skip using the timer altogether and set up a time totalizer using the TOT instruction.

To totalize time, fix the tagname.In value at 1.0 instead of connecting it to another tag. Fix the gain at 1.0. Set tagname.timebase to 0 for seconds, 1 for minutes, 2 for hours, 3 for days. Use the tagname.EN bit to start/stop time totalizing.

Your TOT tag also will contains some elements named .Target and .TargetDev1 and .TargetDev2. These can be used to signal events in much the same way as a timer DN bit works, however unlike a DN bit the TOT doesn't stop counting time when the bits are set.