Tests can be developed for individual modules or the complete program. When the complete program is tested, the data used should adequately test all conditions that may be encountered.

Testing conditions should include values that the program does not expect to encounter. For example, you might include the following conditions:

  • Enter an input value of 40F for an input that is defined to accept values from 50F to 70F.
  • If the program turns a point ON, find out what happens when you turn it OFF.
  • Simulate a sensor or fan motor failure and see how the program reacts.

The precautions taken in programming and testing will show you how the program processes errors and help prevent downtime when the system encounters unusual operating conditions.