1. PID Temperature Controller
Allen Bradley 1771-TCM
Brian Van Eyk

2. Background Applications Plastic injection molding Powder paint
There is a need for quick and accurate temperature control
Two solutions
Sensor with simple logic controller
Smart I/O controller

3. Allen Bradley 1771-TCM Uses PID controller 8 independent control loops
Heating or cooling control
Auto-Tuning software
Speeds up design
Accurate gains
Analog or digital control
Standard PLC-5 rack mount

4. Control Loops Thermocouples used for feedback
Open loop detection
Disable unit or output constant value
Data collected in the TCM is given to the PLC
PLC controls actuator

5. PID Auto-Tuning Auto-Tune calculates PID gains
Gains are stored in TCM module
Gains must be read into PLC data table
TCM can be set to slow, medium or fast response time
TCM memory is volatile
TCM must have gains sent to it or auto-tune whenever power to the module is lost

6. PID Fine-Tuning Fine tuning can be done manually Too much overshoot
Decrease P and I
Increase D
Too slow
Increase P and I
Decrease D

7. Analog vs. Digital Control
TCM module has two possible outputs:
Analog control allows PLC to set the temperature of the heating / cooling device
Digital control gives the PLC the duty cycle for the actuator

8. Alarms Alarms can be set Alarm is sent to the PLC
High and low temperature alarm values
High and low deviations
Can use with dead band or without
Alarm is sent to the PLC
The PLC programmer can do
what they want with the alarm

9. Mounting Termination panel mounted separately Standard DIN style
Mount in panel near thermocouples
Two cables from termination panel to TCM
Provides more accurate temperature readings

10. Questions
Cost - $3,150