TOF - Off Delay Timer

Help Contents

Introduction

The TOF off delay timer function block turns an output off after a delay.

Parameters

ParameterTypeDirectionDescription
INBOOLInputA rising edge starts the timer.
PTTIMEInputThe duration of timer.
QBOOLOutputSet to false after delay PT.
ETTIMEOutputThe elapsed time of the timer.

These timing diagrams show the relationship of the TOF inputs and outputs:

       +---+        +---+ +-----
  IN   |   |        |   | |
     --+   +--------+   +-+

       +--------+   +------------
  Q    |        |   |     
     --+        +---+       

                +---+
               /    |
              /     |
  ET         /      |     +
            /       |    /|
     ------+        +---+ +---

Standards Compliance

Table 37.3 - IEC 61131-3 Second Edition.

Table 46.3a - IEC 61131-3 Third Edition.

Further Information

Standard Function Blocks

To learn about other standard function blocks.

Elementary Data Types

To learn about the different types supported by Fernhill SCADA.

Common Elements

To learn about other IEC 61131-3 Common Elements.

Glossary

For the meaning of terms used in Fernhill SCADA.