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3.11.2 Manual Tuning Procedure (Ziegler and Nichols method)
Step 1 : Adjust the integral (ti) and derivative (td) values to " 0 ". This inhibits the rate and reset action.
Step 2 : Set an arbitrary value of proportional band (Pb) and monitor the control results.
Step 3 : If the original setting introduces a large process oscillation, then gradually increase Pb until
steady cycling occurs. Record this proportional band value (Pc).
Step 4 : Measure the period of steady cycling.
Record this value (Tc) in seconds.
Step 5 : The Control Settings are determined as follows :
- Proportional Band (Pb) = 1.7 Pc
- Integral Time (Ti) = 0.5 Tc
- Derivative Time (Td) = 0.125 Tc
4. TECHNICAL SPECIFICATIONS
INPUT
Type and scale : user configurable
Type
Range
Accuracy
Couple J
-50...1000°C
± 2°C
Couple K
-50...1370°C
± 2°C
Couple T
-270...400°C
± 2°C
Couple E
-50...750°C
± 2°C
Couple B
300...1800°C
± 3°C
Couple R
0...1750°C
± 2°C
Couple S
0...1750°C
± 2°C
Couple N
-50...1300°C
± 2°C
Pt 100
Ω
at 0°C
-200...500°C
± 0,4°C
Voltage
-10...60 mV
± 0,05%
Cold junction compensation : 0.1% ambient typical
Sensor break protection :
Protection mode configurable.
Normal mode rejection :
60 dB
Common mode rejection :
120 dB
Sample rate :
3 times per second
CONTROL
Proportional band :
0...200°C
Integral time (Reset) :
0...3600 seconds
Derivative time (Rate) :
0...1000 seconds
Anti Reset :
Inhibits Integral action outside Proportional Band
Содержание Statop 4849
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