Derivative settings, Derivative settings 227 – Watlow PPC-2000 User Manual
Page 255
PPC-2000 User’s Guide
Chapter 6: Tuning and Control
Doc.# 30002-00 Rev 2.3
Watlow Anafaze
227
Table 6.2
Integral Term and Reset Settings
As a general rule, use 60, 120, 180, or 240 as a starting value
for the Integral.
Derivative Settings
The controller’s Derivative parameter is programmed in
seconds. Some other products use a derivative term called Rate
programmed in minutes. Use the table or the formula to
convert parameters from one form to the other. Table 6.3 shows
Derivative versus Rate; Rate = Derivative/60.
Table 6.3
Derivative Term vs. Rate
As a general rule, set the Derivative to 15% of Integral as a
starting value.
NOTE!
While the basic PID algorithm is well defined and
widely recognized, various controllers implement it
such that parameters may not be taken from one
controller and applied to another with optimum
results even if the above unit conversions are
performed.
Integral
(sec/repeat)
Reset
(repeat/min)
Integral
(sec/repeat)
Reset
(repeat/min)
30
2.0
210
0.28
45
1.3
240
0.25
60
1.0
270
0.22
90
0.66
300
0.20
120
0.50
400
0.15
150
0.40
500
0.12
180
0.33
600
0.10
Derivative
(seconds)
Rate
(minutes)
Derivative
(seconds)
Rate
(minutes)
5
0.08
35
0.58
10
0.16
40
0.66
15
0.25
45
0.75
20
0.33
50
0.83
25
0.41
55
0.91
30
0.50
60
1.0