Micrologix 1500 - How long has the rung been true?

[donl517]

Ok, I know this should be really simple to accomplish but it escapes me. I am trying to time the interval between two conditions, I then need to export that time interval via RS232. How can I get a semi accurate time interval for how long a rung has been true? (I am timing how long it takes a door to open on a part)

What is the best way then to export that data via RS232?

Thanks,
Don

 

[rsdoran]

You did not offer enough details about what you are sending it to by RS232..ex: you could use DDE/OPC and send the info to an Excel file on a PC.

The timing part should not be too difficult but there are several approaches that may be used. Will one condition always be on before the other? Not that important but could simplify things.

IF the above is correct then you can do something like this; the value you need will be in the register. You reset the timer when both conditions become true.

Actually this is a bad example, you would not need the reset using a TON because it will reset if either condition changes. You may need to use an RTO, in that case you would need the reset.

If either condition can become true first then you may need to use 2 rungs with different timers but the ACC value could still be moved to a specific register, you then use the value in that register as needed.

 

[donl517]

I have two lasers both with 2 outputs. Laser 1 is looking for part present (O1), and then door not closed (O2). Laser 2 is looking for door open (O1).

XIC L1 O1, XIO L2 O1, TON

Your example should work with one rung, I was just not sure how to, or if I could capture the ACC value.

I just want to send the data as an ascii string to a data acquisition unit. Can I send it straight from the N7 register or do I need to copy it to the ST registry?

 

[rsdoran]

Maybe someone can offer more help on this part, I have not done ASCII for awhile. I think you will probably have to copy it to the ST register then use the AWT instruction to send it to your data acquisition unit.

 

[donl517]

Thanks for your help. Your example was right on the money. I can capture the data now I just have to decide what I want to do with it.