Industrial Temperature Control With LabVIEW

LabVIEW temperature controlled applications can be done in one of two ways: 

(A) The LabVIEW executable has a PID control loop that monitors a thermocouple or varistor or RTD and controls the heat source

(B) LabVIEW acts as a “Front End”  or host as a sub component does the temperature control such as one of these components:

  1. Off the shelf controller made by a company such as Watlow, Omron, Omega, Chromalox.  These controller typically communicate with LabVIEW using RS232, RS485, RS422, 4-20mA output / input, 0-10V output /input

  2. Industrial grade PLC such as Siemens, fujitsu, Allen Bradley

  3. LabVIEW PXI – Real Time system.  (Using Shared variables, network communication).

When making a decision on which approach to use, there are many considerations to take into account.   These are: 

  • How tight is your control loop?   (What frequency does it need to run at?)

  • What damage can happen to the equipment being controlled or product being processed?  

  • What could happen as a result of a computer hang or crash?

  • How much data do you need to save per day?  Per test run or production run? 

  • Do you need SPC charts for quality control

  • Do you need historical data reporting based on lot ID or batch run?