Hello all,
I having trouble transferring from a manual control to automatic control. At the moment when the valve is in auto, it uses the PID loop to control it. When the vale is in manual it is controlled by changing the valve percentage from the HMI. I have tried to use a MOV instruction and take the manual percentage and place it into the pid out, when the vale is switched to auto. This works sometimes. Example if the valve is at 44% in manual and then I switch to auto the pid loop will hold it at 41% sometimes. Or the valve will be 44% in manual and then when switched to auto the valve will drop to 25% for no apparent reason. I'm not sure how to setup bumpless transfer on the PID. I have read that the .swm instruction in pid needs to be used. Any help would be appreciated. Unfortunately, I'm not a controls engineer so it may have to be dumbed down for me. Thx
I having trouble transferring from a manual control to automatic control. At the moment when the valve is in auto, it uses the PID loop to control it. When the vale is in manual it is controlled by changing the valve percentage from the HMI. I have tried to use a MOV instruction and take the manual percentage and place it into the pid out, when the vale is switched to auto. This works sometimes. Example if the valve is at 44% in manual and then I switch to auto the pid loop will hold it at 41% sometimes. Or the valve will be 44% in manual and then when switched to auto the valve will drop to 25% for no apparent reason. I'm not sure how to setup bumpless transfer on the PID. I have read that the .swm instruction in pid needs to be used. Any help would be appreciated. Unfortunately, I'm not a controls engineer so it may have to be dumbed down for me. Thx