Instruction manual

Although PID control has been used and proved to be an efficient controlling method
by many industries, PID tuning is difficult to deal wit, some sophisticated systems such
as second and higher order systems, long time-lag systems, during set point change
and/or load disturbance. The PID principle is based on a mathematic modeling
which is obtained by tuning the process. Unfortunately, many systems are too
complex to describe in numerical terms precisely. In addition, these systems may
vary from time to time. In order to overcome the imperfections of PID control, Smarter
Logic Technology is introduced. Smarter Logic is a linguistic control which controls the
system by experience and does not need to simulate the system precisely as PID.
Smarter Logic is the OGDEN trade mark for Fuzzy Logic . An ETR with Smarter Logic
continues decision making and will prevent initial overshoot and set point differentials
due to process disturbances. Control results are virtually perfect. Not only is control
performance improved, software and design innovations have made available other
Although PID control has been used and proved to be an efficient controlling method
by many industries, PID tuning is difficult to deal wit, some sophisticated systems such
as second and higher order systems, long time-lag systems, during set point change
and/or load disturbance. The PID principle is based on a mathematic modeling
which is obtained by tuning the process. Unfortunately, many systems are too
complex to describe in numerical terms precisely. In addition, these systems may
vary from time to time. In order to overcome the imperfections of PID control, Smarter
Logic Technology is introduced. Smarter Logic is a linguistic control which controls the
system by experience and does not need to simulate the system precisely as PID.
Smarter Logic is the OGDEN trade mark for
Fuzzy Logic . An ETR with Smarter Logic
continues decision making and will prevent initial overshoot and set point differentials
due to process disturbances. Control results are virtually perfect. Not only is control
performance improved, software and design innovations have made available other
5
Digital communications, RS-485, RS-232 or4-20mAretransmission are available as
an additional option. These options allow ETR-3400 to be integrated with supervisory
Digital communications, RS-485, RS-232 or 4 - 20 mA retransmission are available as
an additional option. These options allow ETR-3400 to be integrated with supervisory
Three different 1)
2)
3)
methods can be used to program the ETR-3400. Use the keys on
the front panel to program the unit manually, Use a PC and setup software to
program the unit via RS-485 or RS-232 COMM port. Use P10A, a hand-held
Three different 1)
2)
3)
methods can be used to program the ETR-3400. Use the keys on
the front panel to program the unit manually, Use a PC and setup software to
program the unit via RS-485 or RS-232 COMM port. Use P10A, a hand-held
PROCESS
PID
FUZZY
MV PV
_
+
SV
+
+
Fuzzy Rule
Fuzzy Inference
Engine
DefuzzifierFuzzifier
Digital
information
Language
information
Digital
information
Figure 1.1
Fuzzy PID System Block
Figure 1.1
Fuzzy PID System Block
The function of Fuzzy Logic is to adjust PID parameters internally in order to make
PID + FUZZY CONTROL
Smarter Logic causes the following:
If temperature difference is large and temperature rate is large, then delta MV is large.
If temperature difference is large and temperature rate is small, then delta MV is small.