Attention

IronPLC can only run very simple programs. The steps described are accurate but many language features are not yet supported.

TON

On-delay timer. Output Q becomes TRUE after input IN has been TRUE for at least the preset time PT.

IEC 61131-3	Section 2.5.2.3.3
Support	Not yet supported

Inputs

Name	Type	Description
IN	BOOL	Timer enable input
PT	TIME	Preset time

Outputs

Name	Type	Description
Q	BOOL	Timer output (TRUE when elapsed time >= PT)
ET	TIME	Elapsed time

Behavior

When IN transitions to TRUE, the elapsed time ET begins counting from T#0s. When ET reaches the preset time PT, the output Q becomes TRUE. If IN returns to FALSE before ET reaches PT, both ET and Q are reset.

Example

VAR
  timer1 : TON;
  start : BOOL;
  done : BOOL;
END_VAR

timer1(IN := start, PT := T#5s);
done := timer1.Q;

See Also

• TOF — off-delay timer

• TP — pulse timer