Retentative Data

[Guest TheDOG]

I have some parameters (about 30) that need initial values. They also need to be reset as needed. How can I make them retentative with ProWorX32 984. We also use Siemens (S-7), AB (1200), and DL205. How can I make all these parameter's valves retentative in all these PLCs? Thanks. TheDOG

[Modiconbob 2]

One easy way is to use a math function (sub, add, mult etc.) to have the result set these values on the first scan of the 984. To change the values, you would just need to change the equation to achieve the desired result. I have used this often to keep pre-calculated values "in the program" rather than just stuffing registers which could get over written by accident or erased during a mistake etc. Let me know if you need more info. Good luck!

[Guest TheDOG]

Thanks, Bob. Yes. U R right. In such a way, you could easily have the initial and the changed values of these parameters. Also, you can use the data editor to do that. Use Data editor to assign initial values to the parameter (addresses). Then you can change these values by using a HIM. When power is off, we may lose these values unless they are in EEPROM. Do Modicon PLCs have EEPROM Instructions? How can we save the parameter values after change, so that they will not be lost when power is off for sometime? Thanks. One easy way is to use a math function (sub, add, mult etc.) to have the result set these values on the first scan of the 984. To change the values, you would just need to change the equation to achieve the desired result. I have used this often to keep pre-calculated values "in the program" rather than just stuffing registers which could get over written by accident or erased during a mistake etc. Let me know if you need more info. Good luck!