9. CustomLogic
9.1 Introduction
9.1.1 Introduction
Access under
Configure > CustomLogic
CustomLogic is used to create and configure customised logical operations for use in the system. These functions are built
using ladder logic elements and can include interaction with external equipment, or more advanced logic interfaces.
This chapter gives a description of the different CustomLogic elements, how to create CustomLogic, examples of simple
ladder logic and further examples of CustomLogic that can be used in practice.
9.1.2 Ladder logic
Ladder logic is used to configure CustomLogic.
Ladder logic is created on the logic grid of the
Block
. The logic that is built between the left and right vertical rails are called
lines. A line can consist of a single input and output or multiple inputs and outputs connected directly to each other or
connected with connectors. The figure below shows an example of a line with one contact placed directly next to the left
vertical rail, and one coil directly next to the right vertical rail.
Figure 9.1
Example of the logic grid with a logic line
The ladder logic can consist of several parallel lines. Lines are always read from the top of the block to the bottom of the
block. Contacts (inputs) are always placed at the beginning of a line and coils (outputs) always at the end. In some cases (for
example a counter block) the number of lines used as input do not match the amount of outputs.
When ladder logic is implemented, the controller:
1. Scans the lines' input conditions.
2. Solves the ladder logic.
3. Sets the output conditions.
A line can consist of up to four element types:
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