Publication 900-UM007D-EN-E - January 2011
5-36
Parameter Functions & Definitions
Proportional action:
P refers to control in which the Manipulated Variable
(MV) is proportional to the deviation (control error).
Integral action:
I gives a control action that is proportional to the time
integral of the deviation. With proportional control, there is normally an offset
(control error). So, proportional action is used in combination with integral
action. As time passes, this control error disappears, and the control
temperature (process value) comes to agree with the set point.
Derivative action:
D gives a control action that is proportional to the time
derivative of the control error. As proportional control and integral control
correct for errors in the control result, the control system will be late in
responding to sudden changes in temperature. Derivative action enables
control that is proportional to a predicted process output to correct for future
error.
➊
Set NONE as the unit for Controllers with 0…50 Millivolt Inputs.
Note:
If the settings for RT (robust tuning) are changed, the Proportional
Band (P), Integral Time (I), and Derivative Time (D) will be initiated.
Related Parameter
•
AT Execute/Cancel (Adjustment function group, page 5-25)
Cooling Coefficient
Conditions of Use:
The control mode must be heating and cooling with the
2-PID control method configured.
Function:
If the heating and cooling characteristics of the control target differ
greatly, preventing satisfactory control characteristics from being obtained by
the same PID parameters, adjust the proportional band (P) at the cooling
Control Output side by adding the cooling coefficient to balance control
between the heating and cooling sides (refer to Figure 4.26).
Table 5.AM
Parameters
Controller Type
Configurable Range
Units
Default
Proportional Band
With Thermocouple or Resistance Detector
(RID)
0.1…999.9
°
C or
°
F
➊
8.0
With Analog Inputs
%FS
10.0
Integral Time
0…3999
Seconds
233
Derivative Time
RT is OFF
0…3999
Seconds
40
RT is ON
0.0…999.9
Seconds
40.0
c-sc
Summary of Contents for Allen-Bradley 900-TC16
Page 1: ...USER MANUAL Bulletin 900 TC8 900 TC16 900 TC32 Series B Temperature Controllers...
Page 2: ...2...
Page 72: ...Publication 900 UM007D EN E January 2011 3 2 Configuration Basic Operation Figure 3 3 900 TC32...
Page 136: ...Publication 900 UM007D EN E January 2011 3 66 Configuration Basic Operation Notes...
Page 340: ...Publication 900 UM007D EN E January 2011 5 112 Parameter Functions Definitions Notes...
Page 350: ...Publication 900 UM007D EN E January 2011 6 10 Troubleshooting Error Indication Notes...
Page 406: ...Publication 900 UM007D EN E January 2011 D 8 Glossary Notes...
