Step7 Duty/Standby block

[ged]

Hello, I posted a thread and it did not seem to go through so I will try again..
I am looking for sample code for a Duty/Standby block for a pump application. I have an existing motor block that feeds into a PID FB41 block. A duty pump is being added. I am duplicating the existing code but now need to control the motor blocks with a duty/Standby block. I would appreciate any pointers. Changeover is based on Runtime, Operator manual select, stop/start or if the Duty pump is not available, defaults to the Standby pump

Thank you for any input.. Ged

 

[TurpoUrpo]

And where is your contribution? You want pointers, but what kind of pointers? Do you need help with the code or with the operation?

 

[cjd1965]

Hi
Are the manual controls 'outside the plc' ie hardwired, in case of plc failure?

With regards to your program, get a sheet of paper and write a list of what you know (inputs etc) and what you want to do (outputs etc)

Write down all intrlocks etc thst you know about, plusa few you dont

Review your existing code and then graft in your extra code.

 

[ged]

thanx for insight