Help!!!!

[iansmiler]

I have the following hardware:

MFP CP8-NT, MFD-80-B, MFD-R16

And heres what I want to achieve:

I have an extruder that is powered by a motor via an inverter, the material that is produced from the extruder is a continual extrusian much like a sausage machine. there is an encoder that monitors the speed of the extrusian (a wheel sits on top of the sausage as it leaves the extruder which is connected to the encoder).
The 'sausage' must always run at the set speed that is set by a potentiometer (or within the MFD Display). heres the tricky part, because of the properties of the material being extruded, running the motor at a set speed does not guarentee that the extrusian is a constant speed. Therefore within the program the encoder must look at the preset setting (set by the pot or within the MFD Display) and adjust the frequency inverter accordingly.
I know that with this unit I have not got an anologue output so was hoping that i could use 2 outputs to ramp up or ramp down the inverter.  I normally write this program for Mitsis FX2N but I promised the Moeller sales guy that I would give this MFD unit a whirl!

Please help!

Ian

[befu]

Hi Ian,

I'm not that expert in programming the MFD-Titan, but if no one of the specialists here jumps in, may be i can give you some hints.

To control the frequency you can use the function block DC (PID-Controller), if necessary in conjunction with the function blocks FT (PT1 signal smoothing filter) and/or LS (value scaling).

Because of the visualisation task the cycle time of the MFD may more or less vary, that could be avoided by using the function block ST (constant cycle time).

To be able to use an analog output you shold use a MFD-RA17 extension device instead of the MFD-R16. Another more expensive solution would be an external hardware, that converts a PWM-Signal generated by a function block PW (puls width modulation) into an analog value.

Hope this helps a little bit

Regards

Bernhard Funk