If you need to make sure that every teacher has at least one period free during lunch time for lunch, you can input it this way:
Example: Lunch between periods 3-5. This means there are 3 periods available. So we can input it making sure that during 3.-5. period teacher can have max 2 lessons.
Go to menu - Specification - Relations - Advanced and input values according to this picture:
This article was viewed 79141 times.53428 / 79141