Tuning may not be the issue. First we need to check on a few other things.
Is the control calling for heat? Is it a heat & cool control? What is the complete part number (P610x/Zxxxx//xxxx)?
My first guess is that the control is on a plastic extruder and there is no cooling or not enough cooling to overcome the frictional heat. Check to see if the control is calling for heat. Go into the Setup Mode and check the Primary Power PPW value. If the value is 0 or close to 0 then the control is doing all it can do to control the temperature by not applying power to the heaters. If frictional heat is too high and there is not enough cooling capacity to overcome it then there is not any more that the control can do. Also check the Secondary Power SPW parameter if present. This is the cooling output for the control. 0% is no cooling, 100% is cooling on all the time.
What are the values for the following Setup parameters?
Primary Output Proportioning Band Pb_P
Secondary Output Proportioning Band Pb_S
Automatic Reset ArSt
Rate rAtE
Overlap OL
Primary Output Upper Power Limit OPuL
Output 1 Cycle Time Ct1
Output 2 Cycle Time Ct2
Depending on the configuration of the control, some of the parameters may not be present. Advise ISE the values of these parameters and the complete model number of the control.
How to navigate between the various modes on the 4100/8100/6100 series controllers: