FESTO SEC-AC-305-PB Drive and Siemens S7 Profibus messaging

Hello,

I have a Festo SEC-AC-305-PB drive and it came with S7 function blocks. The Festo comes with its own commissioning software called Wmemoc where you can set the drive up and monitor different parameters. The Siemens S7 parameters for position setpoint, velocity, etc are configured as DINT (double integer). I want to know how to scale that or convert the number in my PLC to match the values shown in the Wmemoc software. I do not know what number format the drive uses but if I force a decimal value for position that is L#40000 and send that to the drive, the drive shows a number of 25,396820. I want to be able to enter a scaled value in the PLC so that the position shown in the drive Wmemoc software matches the PLC.

Has anyone used this drive with the S7 funtion block that comes with the drive?

Also where can I find a good conversion utility for integer to double integer, decimal to integer, etc?

Thanks
Paul

Just a shot in the dark but you may want to look at the word setup. A real is made up of 2 words. If the drive is sending these backwards then you can get odd numbers. Sometimes you can swap the word order in the HW config sometimes you have to do it in the plc. I would put in a couple of moves and swap the word order an see if the numbers start looking better before I did any scaling.

If you do have to scale then I think is FC105 for scaling real numbers.

Hello,

It seems it is just because the scaling in the drive is in revolutions per second. I figured out how to read the actual speed feedback and used a scale factor to scale it to the right speed. Because the parameters are in DINT format i just used the DI_R (double integer to real) block and scaled from double integer to real and then used a scale factor so it would be the same RPM as the drive shows in the monitoring software. Now my problem is that I cannot find a tool to go backwards so that I can convert R_DI (real to double integer). I would like to have my setpoint for speed in real so I can use a real number scale factor and then convert it to double integer and send it out to the drive. Are there blocks available for this?

Thanks again!
Paul