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
INPUT
Type and scale : user configurable
Type
Couple J
Couple K
Couple T
Couple E
Couple B
Couple R
Couple S
Couple N
Pt 100 Ω at 0°C
Voltage
Cold junction compensation : 0.1% ambient typical
Sensor break protection :
Normal mode rejection :
Common mode rejection :
Sample rate :
CONTROL
Proportional band :
Integral time (Reset) :
Derivative time (Rate) :
Anti Reset :
4. TECHNICAL SPECIFICATIONS
Range
-50...1000°C
-50...1370°C
-270...400°C
-50...750°C
300...1800°C
0...1750°C
0...1750°C
-50...1300°C
-200...500°C
-10...60 mV
Protection mode configurable.
60 dB
120 dB
3 times per second
0...200°C
0...3600 seconds
0...1000 seconds
Inhibits Integral action outside Proportional Band
Accuracy
± 2°C
± 2°C
± 2°C
± 2°C
± 3°C
± 2°C
± 2°C
± 2°C
± 0,4°C
± 0,05%
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