Alarming; Self-Tuning - Beckhoff TwinCAT 3 Manual

7.2

Alarming

The following alarm conditions are continuously monitored by the temperature controller:
• Absolute temperatures (high and low)
• Relative temperatures (in two bands around the set value)
The following hardware conditions related to the sensor can also be linked to the temperature controller:
• Open thermocouple: broken wire to the temperature sensor
• Back voltage: a voltage outside the permitted range is present at the temperature sensor
• Reverse thermocouple: temperature sensor is connected with the wrong polarity
If a current sensor is connected, then the following signals can be linked to the temperature controller:
• Short circuit
• Open circuit
• Leakage current
Requirements
Development environment
TwinCAT 3.1.4006
7.3

Self-tuning

The self-tuning algorithm is based on the classic inflectional tangents method. This method was first
developed by Ziegler and Nichols. It is assumed that a linear P-T1 loop with a delay time is being examined.
The maximum rate of change is determined following an experimental step. This is achieved through
TC3 Temperature Controller
target platform
PC or CX (x86)
Version: 1.1
PLC libraries to include
Tc2_TempController
Appendix
45