Data logging

I am using rs logix 500 with a AB Micrologix 1100. How can i take a value that I would like to record 5 times a day and save it to a table? I am trying to save a temperature 5 times a day for 365 days a year if possible. Is there any other way than writing 1825 lines of code.Thanks

http://sourceforge.net/projects/advancedhmi/

You could look at AdvancedHMI to log the data into a database using some Visual Basic code.

Just a thought,

Looks like a nice piece of software. The pieces of equipment are located out on the tarmac at airport runways not connected to a pc. We are currently using CMore HMI's on them. Tried to figure out a way using logic but I'm new to programming and haven't found one yet.

Bowhunter1980.dkn said:

Looks like a nice piece of software. The pieces of equipment are located out on the tarmac at airport runways not connected to a pc. We are currently using CMore HMI's on them. Tried to figure out a way using logic but I'm new to programming and haven't found one yet.

Click to expand...

Can't the C-More log this data for you?

If you want it stored in the PLC, you would not need 1825 lines of code, but you would need that many free data table spots..which is quite reasonable.

The ML1100 also has some built in data logging features which I have never used:

http://www.theautomationstore.com/allen-bradley-micrologix-data-logging/

I think the best option, if there's enough memory space on the MicroLogix, is to create an array and use a pointer. The array would store time and temperature. Then I would read the internal clock and compare with the 5 preset (5 different times). If the internal time coincides with a preset, the logic would save the time/temperature pair on the pointed location of the array. The pointer has to be incremented by one.

Finally, the logic would check if the pointer has reached the last location of the array. If it's true, reset the poninter to the first location.

There is logging in the C-more.
http://www.automationdirect.com/static/specs/ea9pgming.pdf
This will log to a SD card or USB drive.

Regards,

Thanks y'all for the info. I am going to try some of it when I get to the office in the morning. nhatsen..do you have an example of what you are describing?

I just realize that you can only have 256 element in file in the micrologix world. Still, it won't be too bad. You can make 10 files. Say, N10 to N19.. do the index like this:

Copy data to N10:[date] and if date>256, copy date to N10:[(date-256)] for the 1st of 5
Copy data to N11:[date]... blah blah... for 2nd of 5..

The trickier part is to export the data out from it, I'm thinking you can create a excel spreadsheet and link the cells to the data using a cheap OPC server. You can search around to see how to do that.

Thanks harryting

As OkiePC said, MicroLogix has a Data Logging function. Please read page 433 of the manual:

http://literature.rockwellautomation.com/idc/groups/literature/documents/rm/1763-rm001_-en-p.pdf

The MicroLogix 1100 processor has 128K bytes (128 x 1024) of additional memory for data logging purposes.

Click to expand...

You have information about internal clock (RTC) on pages 51, 466 and 486.

I would review the Data Logging option in the link provided it's probably your best option if you need to do it in the PLC. I have never used it and I don't believe an array of N files will do anything for you. You can't create any type of valid integer timestamp that will be small enough to store in an N file and give you Month/Date/Year, HH/MM/SS resolution.

Perhaps you could create a lot of string tables, and create a MM/DD/YY - HH:MM:SS timestamp strings formatted each record. But probably would eat up too much memory in your controller to be viable.

If you want to try create 12 string files (correlates to the month), which should give you enough elements for 155 records per month. Then write logic to built your formatted string based on PLC times and see how you fair. Keep in mind the PLC time needs to be sync'd with some master periodically.