B - Glossary Of Terms - Partlow MIC 8200 Installation And Operation Manual

P 68
AGE
Appendix B
Glossary of Terms
Automatic Reset (Integration)
Automatic reset is a Tune mode parameter that will bias the proportional output(s) to compen-
sate for process load variations. This parameter is adjustable from 0.0 to 100.0 repeats per
minute. Factory default is 0.0. The display codes are ArS1 for proportional Output 1 and/or
ArS2 for proportional Output 2. The Auto Tune feature will select the ArS1 setting for a
heating output.
Automatic Transfer
Automatic transfer is a feature selected in the Program mode that will allow the instrument to
shift from the Manual to the Control mode of operation automatically when the process value
reaches setpoint.
Auto Tune
Auto Tune automatically determines the Tune mode parameters for a proportional heating
output assigned to Output 1. The Ziegler - Nichols method is used to determine the Tune
mode parameters.
Auto Tune Deviation Lower Limit
If AdLL = 0, when the AUTO TUNE key is pressed, the process response calculations will
occur during the time the process variable rises to the point 1/2 of the way between the
setpoint value and the process value when the key was pressed.
If AdLL > 0, when the AUTO TUNE key is pressed the process response calculations will
begin when the process value rises above the point that is the result of subtracting AdLL from
setpoint.
Auto Tune Deviation Upper Limit
If ASo = 0, the Auto Tune function will not operate unless the process value is < the SP-
AduL value. This can be useful to prevent unwanted retuning of the process when the
process value (PV) is > the Setpoint value minus the AduL value.
If ASo = 1, Auto Tune will function if the PV is within the AduL value from setpoint. However,
if the PV is > SP-AduL, the heating output will be turned off until the
PV < SP-AduL. At this point the heating output will be turned on so the control repsonse can
be calculated.
In order for AduL to have an effect on Auto Tuning, the AduL value should be greater than
20 degrees or 5 % of the setpoint value, whichever is greater, to initiate the Auto Tune
function.
SP
SP - AduL
Auto Tune will not initiate if PV is above
this line, when the AUTO TUNE key is depressed
Auto Tune will function if the PV is within
this area (below SP-AduL), when the AUTO TUNE
key is depressed