RSLogix Stopwatch - Help

Hi there.

I'm trying to make a logic where a RTO function will count the time an equipment takes to complete a certain movement. This movement can vary, so the time can vary too. The timer will always start when the movement starts and at the end of it, it will store the time measured on DINT tag. I was able to develop this part.

The tricky part is that I want to store, on a separated tag, the best time measured. So, this other DINT tag will always store the best time, and have any faster time re-written on it.

Anyone could help me on this?

Thanks!

Use a LES instruction in front of a MOV so the new, lower time will be moved to the "best time" DINT if the new time is less than the old "best time".

mscholz said:

Use a LES instruction in front of a MOV so the new, lower time will be moved to the "best time" DINT if the new time is less than the old "best time".

Click to expand...

Will try that out. Thank you, mscholz!

You can also use a array and the FIFO instruction to store each time. If you wanted to store the last 100 or so cycle times.

I would parse from the real-time clock a couple of timestamps; mark the beginning and end, then solve for time elapsed per movement. You will have much greater accuracy than Timers permit (you are measuring performance, after all!) and you can leverage a UDT in the form of a DateTime object that corresponds to the RTC-provided fields. You could then create a UDT that encapsulates a pair of DateTime UDT (start/end) per movement and create an array of such, or just store the calculated elapsed time itself into an array of DateTime objects and discard the start/end timestamps. This will make movement comparisons a very easy problem to solve.