PCS7 Ramp Function

Hello! I need some tips on how to make a ramp function block in PCS7. I'm quite new to PCS7 and PLC programming. It is for making a soft opening of a control-valve.

I imagine a block with some inputs:
iCmd (bool)
iMax (Real)
iMin(Real)
iTime(Real?)

Outputs:
oSignal (Real)

iTime is the time (maby in milliseconds?) it should take for the output oSignal to change from iMin to iMax.

iCmnd is the command signal.
1=Ramping starts.
0=output is instantly set to iMin again.

Any suggestions on how to approach this?

Thanks.

JSMTek said:

Hello! I need some tips on how to make a ramp function block in PCS7. I'm quite new to PCS7 and PLC programming. It is for making a soft opening of a control-valve.

I imagine a block with some inputs:
iCmd (bool)
iMax (Real)
iMin(Real)
iTime(Real?)

Outputs:
oSignal (Real)

iTime is the time (maby in milliseconds?) it should take for the output oSignal to change from iMin to iMax.

iCmnd is the command signal.
1=Ramping starts.
0=output is instantly set to iMin again.

Any suggestions on how to approach this?

Thanks.

Click to expand...

There is one in the library already

Hi

I was looking for some ramp function for vlave in PCS7 some time before and when I didn't find it I make it my self.

My Ramp has little bit different purpose, but the main pricipe is the same.

iCmnd is OK
iMax and iMin is important
iTime - I think you don't need it, cause it's enough if you set the correct calling time in CFCs block. (if you use the CFC).
You need something like iDiff, that will be the minimum step that will be added (subtracted) to actual valve position ot each calling of that function. And af course you need the actual position of valve iAct or some inner memory for memorize the last output.

So what you think about it ???

...and I forgot

if you vant to control the openning and closing, you should add som direction control

iCmndOpen
iCmndClose

Great

Thanks for the tips biomorf!
Yes i'm using CFC.
I'll give it a try.