Soft Start and Soft Stop Analog Output Using Encoder

[hakannium]

Hello everyone. I'm new to the forum. I have a problem with the encoder and PID. We need to turn an encoder controlled rollover. I am using s7-1500 tia portal v15.1. We have to slow down the speed of the engine during the first starts and stops. In other words, it will stay slow and accelerate, after going at a constant speed, it will slow down near the end. how can I do that.?

 

[parky]

More information is required for example what is the drive ? I assume it will be a VFD type as you are using an analogue why a PID ? etc.
The first thing that comes to mind is set the PID to manual with a fixed speed on the start command, then after a time or number of encoder pulses ramp to the required speed (if PID switch PID to auto) then when within say 10% of travel switch back to Manual PID with a fixed speed.
Never done it with a PID but done many VFD drives for positioning in that mode it is just a case of setting the analogue output to a pre-set low speed, after so many pulses from the encoder set analogue to required speed and the same at the end of travel.