Standard Function Blocks

Help Contents

Introduction

The IEC-61131-3 standard defines a number of function blocks, which are supported in Fernhill SCADA:

Function Block Type Keywords Explanation
Bistable SR, RS Set and reset dominant bistables.
Edge Detector R_TRIG, F_TRIG Rising and falling edge detectors.
Up Counter CTU Counts up from zero to a preset value.
Down Counter CTD Counts down from a preset value to zero.
Pulse Timer TP Generate a fixed duration pulse.
On Delay Timer TON Turn an output on after a delay.
Off Delay Timer TOF Turn an output off after a delay.

Note: Standard Function Blocks require Fernhill SCADA Version 1.2 or later.

Further Information

Common Elements

To learn about other common language elements.

Glossary

For the meaning of terms used in Fernhill SCADA.