panelview+400 and data logging

[hopefull harry]

We have a system consisting of a ML1100 with an added 2 chan analog card and a panelview + 400.

The customer wants to keep records of a pressure switch readings (a 4-20 mA analog signal scaled in the ML1100 program to 0-400) which we have setup through the panelview saving the data to a storage card installed in the panelview itself.Then by converting the data log file from the storage card using the “digconverter” utility (free download from rockwell) the customer is able to read the data using a XL spreadsheet.

At this stage the data is logged as soon as the system is powered up it is logging 0-400 kPa.The customer is only interested in readings of over 250 kPa.

My question is can a trigger be set for the panelview to only log data when when the pressure switch reading is 250 kPa and above instead of logging from the initial power up ?.

 

[Alan Case]

I had a quick look and I would try to copy all the values of the data table above 250 into a new data table in the PLC. Then set the PV to log with a trigger of "change" not the periodic trigger. I think you should be able to then have it log every new value above 250..
Regards Alan Case

 

[hopefull harry]

hi alan i think i have the guts of what your getting at.in the plc prog if i have a rung comparing the 0-400 readout for greater than or equal to 250 then when this is true move the 250 and above readout to another file and this will now be our log file.this will be triggered a "change" % and not periodic.
thankyou for your input alan

 

[Alan Case]

That is pretty well it. The panelview will look at the new file and any change of greater than 0% will be the trigger to write the log. May take a bit of trial and error but it should work.
Alan Case