Storing Data & Reading Data

[AaronDDSA]

if any one can help?? im busy with a project the requires me to use a flow meter(15-300l/min,4-20ma) im controlling a hydraulic cylinder and it has a flow meter on the forward action i have 4-20mA FX3U-4AD-ADP Analog Card i have to move the hydraulic cylinder when it stops it must save the data value and them when i move the hydraulic cylinder it needs to add to the Saved Data and then if stopped it needs to save the data again im not sure on how to store and retrieve the data

[Ron_S]

Probably the best way is to use an index register (depending on what plc you are using V or Z) and increment the register number each time you need to take a reading.

[AaronDDSA]

Hi Spark I'm Using a FX3U PLC

[Ron_S]

And to what are you retrieving the data to? Normally you would move the data into an indexed register. Ie , [MOVP D100V]

[Hatchy]

You need a time reference to store the data, like once a second while it's running and then somewhere to move it to when finished. Index registers are fine or you could use an array to store the data and increment the array position once a second whilst the cylinder is moving using the incremented second counter as the array position. That way the last populated position in the array is your overall runtime and the division number for average flow rate, just dimension the array larger than your longest cycle time!